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1

equilibrium

The sense of balance

2

gestation

The sense of taste; Latin geusis means “taste”

3

hearing

The sense or perception of sound

4

olfaction

The sense of smell; root osm/o means “smell”

5

proprioception

The awareness of posture, movement, and changes in equilibrium; receptors are located in muscles, tendons, and joints

6

sensory receptor

A sensory nerve ending or a specialized structure associated with a sensory nerve that responds to a stimulus

7

tactile

Pertaining to the sense of touch

8

vision

The sense by which the shape, size, and color of objects are perceived by means of the light they give off

9

auditory tube

The tube that connects the middle ear with the nasopharynx and serves to equalize pressure between the outer and middle ear (root: salping/o); pharyngotympanic tube; originally called the eustachian tube

10

cerumen

The brownish, waxlike secretion formed in the external ear canal to protect the ear and prevent infection; adjective: ceruminous

11

cochlea

The coiled portion of the inner ear that contains the receptors for hearing (root: cochle/o)

12

eustachian tube

The tube that connects the middle ear with the nasopharynx and serves to equalize pressure between the outer and middle ear (root: salping/o); auditory tube

13

external auditory canal

Tube that extends from the pinna of the ear to the tympanic membrane; external auditory meatus

14

incus

The middle ossicle of the ear

15

labyrinth

The inner ear, named for its complex structure, which resembles a maze

16

malleus

The ossicle of the middle ear that is in contact with the tympanic membrane and the incus

17

ossicles

The small bones of the middle ear, the malleus, incus, and stapes

18

pinna

The projecting part of the outer ear; auricle

19

semicircular canals

The three curved channels of the inner ear that hold receptors for equilibrium

20

spiral organ

The hearing receptor, which is located in the cochlea of the inner ear; organ of Corti

21

stapes

The ossicle that is in contact with the inner ear (root: staped, stapedi/o)

22

tympanic membrane

The membrane between the external auditory canal and the middle ear (tympanic cavity); the eardrum. It serves to transmit sound waves to the ossicles of the middle ear (root: myring/o, tympan/o)

23

vestibular apparatus

The portion of the inner ear that is concerned with the sense of equilibrium; consists of the vestibule and the semicircular canals (root: vestibul/o)

24

vestibule

The chamber in the inner ear that holds some of the receptors for equilibrium

25

vestibulocochlear nerve

The nerve that transmits impulses for hearing and equilibrium from the ear to the brain; eighth cranial nerve; auditory or acoustic nerve

26

acoustic neuroma

A tumor of the eighth cranial nerve sheath; although benign, it can press on surrounding tissue and produce symptoms; also called a schwannoma or neurilemoma

27

conductive hearing loss

Hearing impairment that results from blockage of sound transmission to the inner ear

28

Ménière disease

A disease associated with increased fluid pressure in the inner ear and characterized by hearing loss, vertigo, and tinnitus

29

otitis externa

Inflammation of the external auditory canal; swimmer's ear

30

otitis media

Inflammation of the middle ear with accumulation of serous (watery) or mucoid fluid

31

otosclerosis

Formation of abnormal and sometimes hardened bony tissue in the ear. It usually occurs around the oval window and the footplate (base) of the stapes, causing immobilization of the stapes and progressive loss of hearing

32

sensorineural hearing loss

Hearing impairment that results from damage to the inner ear, eighth cranial nerve, or auditory pathways in the brain

33

tinnitus

A sensation of noises, such as ringing or tinkling, in the ear

34

vertigo

An illusion of movement, as of the body moving in space or the environment moving about the body; usually caused by disturbances in the vestibular apparatus. Used loosely to mean dizziness or lightheadedness

35

myringotomy

Surgical incision of the tympanic membrane; performed to drain the middle ear cavity or to insert a tube into the tympanic membrane for drainage

36

stapedectomy

Surgical removal of the stapes; it may be combined with insertion of a prosthesis to correct otosclerosis

37

aural

Pertaining to or perceived by the ear

38

decibel (dB)

A unit for measuring the relative intensity of sound

39

hertz (Hz)

A unit for measuring the frequency (pitch) of sound

40

mastoid process

A small projection of the temporal bone behind the external auditory canal; it consists of loosely arranged bony material and small, air-filled cavities

41

stapedius

A small muscle attached to the stapes. It contracts in the presence of a loud sound, producing the acoustic reflex

42

cholesteatoma

A cystlike mass containing cholesterol that is most common in the middle ear and mastoid region; a possible complication of chronic middle ear infection

43

labyrinthitis

Inflammation of the labyrinth of the ear (inner ear); otitis interna

44

mastoiditis

Inflammation of the air cells of the mastoid process

45

presbycusis

Loss of hearing caused by aging; also presbyacusis

46

audiometry

Measurement of hearing

47

electronystagmography (ENG)

A method for recording eye movements by means of electrical responses; such movements may reflect vestibular dysfunction

48

otorhinolaryngology (ORL)

The branch of medicine that deals with diseases of the ear(s), nose, and throat (ENT); also called otolaryngology (OL)

49

otoscope

Instrument for examining the ear

50

Rinne test

Test that measures hearing by comparing results of bone conduction and air conduction

51

spondee

A two-syllable word with equal stress on each syllable; used in hearing tests; examples are toothbrush, baseball, cowboy, pancake

52

Weber test

Test for hearing loss that uses a vibrating tuning fork placed at the center of the head

53

accommodation

Adjustment of the lens’s curvature to allow for vision at various distances

54

aqueous humor

Fluid that fills the eye anterior to the lens

55

choroid

The dark, vascular, middle layer of the eye (roots: chori/o, choroid/o); part of the uvea (see below)

56

ciliary body

The muscular portion of the uvea that surrounds the lens and adjusts its shape for near and far vision (root: cycl/o)

57

cone

A specialized cell in the retina that responds to light; cones have high visual acuity, function in bright light, and respond to colors

58

conjunctiva

The mucous membrane that lines the eyelids and covers the eyeball’s anterior surface

59

convergence

Coordinated movement of the eyes toward fixation on the same point

60

cornea

The clear, anterior portion of the sclera (root: corne/o, kerat/o)

61

eye

The organ of vision (root: opt/o, ocul/o, ophthalm/o)

62

fovea

The tiny depression in the retina that is the point of sharpest vision; fovea centralis, central fovea

63

iris

The muscular colored ring between the lens and the cornea; regulates the amount of light that enters the eye by altering the size of the pupil at its center (roots: ir, irid/o, irit/o) plural: irides

64

lacrimal glands

Pertaining to tears (roots: lacrim/o, dacry/o)

65

lens

The transparent, biconvex structure in the anterior portion of the eye that refracts light and functions in accommodation (roots: lent/i, phak/o)

66

macula

A small spot or colored area; used alone to mean the yellowish spot in the retina that contains the fovea

67

optic disk

The point where the optic nerve joins the retina; at this point there are no rods or cones; also called the blind spot or optic papilla

68

orbit

The bony cavity that contains the eyeball

69

palpebra

An eyelid; a protective fold (upper or lower) that closes over the anterior surface of the eye (root: palpebr/o, blephar/o; adjective” palpebral; plural: palpebrae)

70

pupil

The opening at the center of the iris (root: pupill/o)

71

refraction

The bending of light rays as they pass through the eye to focus on a specific point on the retina; also the determination and correction of ocular refractive errors

72

retina

The innermost, light-sensitive layer of the eye; contains the rods and cones, the specialized receptor cells for vision (root: retin/o)

73

rod

A specialized cell in the retina of the eye that responds to light; rods have low visual acuity, function in dim light, and do not discriminate color

74

sclera

The tough, white, fibrous outermost layer of the eye; the white of the eye (root: scler/o)

75

uvea

The middle, vascular layer of the eye (root: uve/o); consists of the choroid, ciliary body, and iris

76

visual acuity

Sharpness of vision

77

vitreous body

The transparent jellylike mass that fills the main cavity of the eyeball; also called vitreous humor

78

age-related macular degeneration (AMD)

Deterioration of the macula associated with aging; macular degeneration impairs central vision

79

astigmatism

An error of refraction caused by irregularity in the curvature of the cornea or lens

80

cataract

Opacity of the lens of the eye

81

conjunctivitis

Inflammation of the conjunctiva; pinkeye

82

diabetic retinopathy

Degenerative changes in the retina associated with diabetes mellitus

83

glaucoma

A disease of the eye caused by increased intraocular pressure that damages the optic disk and causes loss of vision. Usually results from faulty fluid drainage from the anterior portion of the eye

84

hyperopia

An error of refraction in which light rays focus behind the retina and objects can be seen clearly only when far from the eye; farsightedness; also called hypermetropia

85

myopia

An error of refraction in which light rays focus in front of the retina and objects can be seen clearly only when very close to the eye; nearsightedness

86

ophthalmia neonatorum

Severe conjunctivitis usually caused by infection with gonococcus during birth

87

phacoemulsification

Removal of a cataract by ultrasonic destruction and extraction of the lens

88

presbyopia

Changes in the eye that occur with age; the lens loses elasticity and the ability to accommodate for near vision

89

retinal detachment

Separation of the retina from the underlying layer of the eye

90

trachoma

An infection caused by Chlamydia trachomatis leading to inflammation and scarring of the cornea and conjunctiva; a common cause of blindness in underdeveloped countries

91

canthus

The angle at either end of the slit between the eyelids

92

diopter

A measurement unit for the refractive power of a lens

93

emmetropia

The normal condition of the eye in refraction, in which parallel light rays focus exactly on the retina

94

fundus

A bottom or base; the region farthest from the opening of a structure. The fundus of the eye is the back portion of the inside of the eyeball as seen with an ophthalmoscope

95

meibomian gland

A sebaceous gland in the eyelid

96

tarsus

The framework of dense connective tissue that gives shape to the eyelid; tarsal plate

97

zonule

A system of fibers that holds the lens in place; also called suspensory ligaments

98

amblyopia

A condition that occurs when visual acuity is not the same in the two eyes in children (prefix ambly means “dim”). Disuse of the poorer eye will result in blindness if not corrected. Also called “lazy eye”

99

anisocoria

Condition in which the two pupils (root: cor/o) are not of equal size

100

blepharoptosis

Drooping of the eyelid

101

chalazion

A small mass on the eyelid resulting from inflammation and blockage of a meibomian gland

102

drusen

Small growths that appear as tiny yellowish spots beneath the retina of the eye; typically occur with age but also occur in certain abnormal conditions

103

floater

A small moving object in the field of vision that originates in the vitreous body. Floaters appear as spots or threads and are caused by benign degenerative or embryonic deposits in the vitreous body that cast a shadow on the retina

104

hordeolum

Inflammation of a sebaceous gland of the eyelid; a sty

105

keratoconus

Conical protrusion of the corneal center

106

miosis

Abnormal contraction of the pupils (from Greek, meaning “diminution”)

107

mydriasis

Pronounced or abnormal dilation of the pupil

108

nyctalopia

Night blindness. Inability to see well in dim light or at night (root: nyct/o); often due to lack of vitamin A, which is used to make the pigment needed for vision in dim light

109

nystagmus

Rapid, involuntary, rhythmic movements of the eyeball; may occur in neurologic diseases or disorders of the inner ear's vestibular apparatus

110

papilledema

Swelling of the optic disk (papilla); choked disk

111

phlyctenule

A small blister or nodule on the cornea or conjunctiva

112

pseudophakia

A condition in which a cataractous lens has been removed and replaced with a plastic lens implant

113

retinitis

Inflammation of the retina; causes include systemic disease, infection, hemorrhage, exposure to light

114

retinitis pigmentosa

A hereditary chronic degenerative disease of the retina that begins in early childhood. There is atrophy of the optic nerve and clumping of pigment in the retina.

115

retinoblastoma

A malignant glioma of the retina; usually appears in early childhood and is sometimes hereditary; fatal if untreated, but current cure rates are high

116

scotoma

An area of diminished vision within the visual field

117

strabismus

A deviation of the eye in which the visual lines of each eye are not directed to the same object at the same time. Also called heterotropia or squint. The various forms are referred to as -tropias, with the direction of turning indicated by a prefix, such as esotropia (inward), exotropia (outward), hypertropia (upward), and hypotropia (downward). The suffix -phoria is also used, as in esophoria

118

synechia

Adhesion of parts, especially adhesion of the iris to the lens and cornea (plural: synechiae)

119

xanthoma

A soft, slightly raised, yellowish patch or nodule usually on the eyelids; occurs in the elderly; also called xanthelasma

120

canthotomy

Surgical division of a canthus

121

cystitome

Instrument for incising the lens capsule

122

electroretinography (ERG)

Study of the electrical response of the retina to light stimulation

123

enucleation

Surgical removal of the eyeball

124

gonioscopy

Examination of the angle between the cornea and the iris (anterior chamber angle) in which fluids drain out of the eye (root goni/o means “angle”)

125

keratometer

An instrument for measuring the curvature of the cornea

126

mydriatic

A drug that causes dilation of the pupil

127

phorometer

An instrument for determining the degree and kind of strabismus

128

retinoscope

An instrument used to determine refractive errors of the eye; also called a skiascope

129

slit-lamp biomicroscope

An instrument for examining the eye under magnification

130

Snellen chart

A chart printed with letters of decreasing size used to test visual acuity when viewed from a set distance; results reported as a fraction giving a subject's vision compared with normal vision at a distance of 20 feet

131

tarsorrhaphy

Suturing together of all or part of the upper and lower eyelids

132

tonometer

An instrument used to measure fluid pressure in the eye

133

aorta

The largest artery. It receives blood from the left ventricle and branches to all parts of the body (root: aort/o)

134

aortic valve

The valve at the entrance to the aorta

135

apex

The point of a cone-shaped structure (adjective, apical). The apex of the heart is formed by the left ventricle and is pointed toward the inferior and left

136

artery

A vessel that carries blood away from the heart. All except the pulmonary and umbilical arteries carry oxygenated blood (root: arteri/o)

137

arteriole

A small vessel that carries blood from the arteries into the capillaries (root: arteriol/o)

138

atrioventricular (AV) node

A small mass in the lower septum of the right atrium that passes impulses from the sinoatrial (SA) node toward the ventricles

139

AV bundle

A band of fibers that transmits impulses from the atrioventricular (AV) node to the top of the interventricular septum. It divides into the right and left bundle branches, which descend along the two sides of the septum; the bundle of His

140

atrioventricular (AV) valve

A valve between the atrium and ventricle on the right and left sides of the heart. The right AV valve is the tricuspid valve; the left is the mitral valve

141

atrium

An entrance chamber, one of the two upper receiving chambers of the heart (root atri/o)

142

blood pressure

The force exerted by blood against the wall of a vessel

143

bundle branches

Branches of the AV bundle that divide to the right and left sides of the interventricular septum

144

capillary

A microscopic blood vessel through which materials are exchanged between the blood and the tissues

145

cardiovascular system

The part of the circulatory system that consists of the heart and the blood vessels

146

depolarization

A change in electrical charge from the resting state in nerves or muscles

147

diastole

The relaxation phase of the heartbeat cycle; adjective, diastolic

148

electrocardiography (ECG)

Study of the electrical activity of the heart as detected by electrodes (leads) placed on the surface of the body. Also abbreviated EKG from the German electrokardiography

149

endocardium

The thin membrane that lines the chambers of the heart and covers the valves

150

epicardium

The thin outermost layer of the heart wall

151

functional murmur

Any sound produced as the heart functions normally

152

heart

The muscular organ with four chambers that contracts rhythmically to propel blood through vessels to all parts of the body (root: cardi/o)

153

heart rate

The number of times the heart contracts per minute; recorded as beats per minute (BPM)

154

heart sounds

Sounds produced as the heart functions. The two loudest sounds are produced by alternate closing of the valves and are designated S1 and S2

155

inferior vena cava

The large inferior vein that brings blood back to the right atrium of the heart from the lower body

156

left AV valve

The valve between the left atrium and the left ventricle; the mitral valve or bicuspid valve

157

mitral valve

The valve between the left atrium and the left ventricle; the left AV valve or bicuspid valve

158

pericardium

The fibrous sac that surrounds the heart

159

pulmonary artery

The vessel that carries blood from the right side of the heart to the lungs

160

pulmonary circuit

The system of vessels that carries blood from the right side of the heart to the lungs to be oxygenated and then back to the left side of the heart

161

pulmonary veins

The vessels that carry blood from the lungs to the left side of the heart

162

pulmonary valve

The valve at the entrance to the pulmonary artery

163

pulse

The wave of increased pressure produced in the vessels each time the ventricles contract

164

Purkinje fibers

The terminal fibers of the conducting system of the heart. They carry impulses through the walls of the ventricles.

165

repolarization

A return of electrical charge to the resting state in nerves or muscles

166

right AV valve

The valve between the right atrium and right ventricle; the tricuspid valve

167

septum

A wall dividing two cavities, such as the chambers of the heart

168

sinus rhythm

Normal heart rhythm

169

sinoatrial (SA) node

A small mass in the upper part of the right atrium that initiates the impulse for each heartbeat; the pacemaker

170

sphygmomanometer

An instrument for determining arterial blood pressure (root sphygm/o means “pulse”); blood pressure apparatus or cuff

171

superior vena cava

The large superior vein that brings deoxygenated blood back to the right atrium from the upper body

172

systemic circuit

The system of vessels that carries oxygenated blood from the left side of the heart to all tissues except the lungs and returns deoxygenated blood to the right side of the heart

173

systole

The contraction phase of the heartbeat cycle; adjective: systolic

174

valve

A structure that keeps fluid flowing in a forward direction (root: valv/o, valvul/o)

175

vein

A vessel that carries blood back to the heart. All except the pulmonary and umbilical veins carry blood low in oxygen (root: ven/o, phleb/o)

176

ventricle

A small cavity. One of the two lower pumping chambers of the heart (root: ventricul/o)

177

venule

A small vessel that carries blood from the capillaries to the veins

178

vessel

A tube or duct to transport fluid (root: angi/o, vas/o, vascul/o)

179

aneurysm

A localized abnormal dilation of a blood vessel, usually an artery, caused by weakness of the vessel wall; may eventually burst

180

angina pectoris

A feeling of constriction around the heart or pain that may radiate to the left arm or shoulder, usually brought on by exertion; caused by insufficient blood supply to the heart

181

arrhythmia

Any abnormality in the rate or rhythm of the heartbeat (literally “without rhythm;” note doubled r). Also called dysrhythmia

182

arteriosclerosis

Hardening (sclerosis) of the arteries, with loss of capacity and loss of elasticity, as from fatty deposits (plaque), deposit of calcium salts, or formation of scar tissue

183

atherosclerosis

The development of fatty, fibrous patches (plaques) in the lining of arteries, causing narrowing of the lumen and hardening of the vessel wall. The most common form of arteriosclerosis (hardening of the arteries). The root ather/o means “porridge” or “gruel”

184

bradycardia

A slow heart rate of less than 60 bpm

185

cerebrovascular accident (CVA)

Sudden damage to the brain resulting from reduction of blood flow. Causes include atherosclerosis, embolism, thrombosis, or hemorrhage from a ruptured aneurysm; commonly called stroke

186

clubbing

Enlargement of the ends of the fingers and toes caused by growth of the soft tissue around the nails. Seen in a variety of diseases in which there is poor peripheral circulation.

187

coarctation of the aorta

Localized narrowing on the aorta with restriction of blood flow

188

C-reactive protein

Protein produced during systemic inflammation, which may contribute to atherosclerosis; high CRP levels can indicate cardiovascular disease and its prognosis

189

cyanosis

Bluish discoloration of the skin caused by lack of oxygen

190

deep vein thrombosis (DVT)

Thrombophlebitis involving the deep veins

191

diaphoresis

Profuse sweating

192

dissecting aneurysm

An aneurysm in which blood enters the arterial wall and separates the layers. Usually involves the aorta

193

dyslipidemia

Disorder in serum lipid levels, which is an important factor in development of atherosclerosis. Includes hyperlipidemia (high lipids), hypercholesterolemia (high cholesterol), and hypertriglyceridemia (high triglycerides)

194

dyspnea

Difficult or labored breathing (-pnea)

195

edema

Swelling of body tissues caused by the presence of excess fluid (see Fig. 6-4). Causes include cardiovascular disturbances, kidney failure, inflammation, and malnutrition

196

embolism

Obstruction of a blood vessel by a blood clot or other matter carried in the circulation

197

embolus

A mass carried in the circulation. Usually a blood clot, but also may be air, fat, bacteria, or other solid matter from within or from outside the body

198

fibrillation

Spontaneous, quivering, and ineffectual contraction of muscle fibers, as in the atria or the ventricles

199

heart block

An interference in the conduction system of the heart resulting in arrhythmia

200

heart failure

A condition caused by the inability of the heart to maintain adequate circulation of blood

201

hemorrhoid

A varicose vein in the rectum

202

hypertension

A condition of higher-than-normal blood pressure. Essential (primary, idiopathic) hypertension has no known cause

203

infarct

An area of localized necrosis (death) of tissue resulting from a blockage or a narrowing of the artery that supplies the area

204

ischemia

Local deficiency of blood supply caused by obstruction of the circulation (root: hem/o)

205

murmur

An abnormal heart sound

206

myocardial infarction (MI)

Localized necrosis (death) of cardiac muscle tissue resulting from blockage or narrowing of the coronary artery that supplies that area. Myocardial infarction is usually caused by formation of a thrombus (clot) in a vessel

207

occlusion

A closing off or obstruction, as of a vessel

208

patent ductus arteriosus

Persistence of the ductus arteriosus after birth. The ductus arteriosus is a vessel that connects the pulmonary artery to the descending aorta in the fetus to bypass the lungs

209

phlebitis

Inflammation of a vein

210

plaque

A patch. With regard to the cardiovascular system, a deposit of fatty material and other substances on a vessel wall that impedes blood flow and may block the vessel. Atheromatous plaque

211

rheumatic heart disease

Damage to heart valves after infection with a type of streptococcus (group A hemolytic streptococcus). The antibodies produced in response to the infection produce valvular scarring, usually involving the mitral valve

212

septal defect

An opening in the septum between the atria or ventricles; a common cause is persistence of the foramen ovale (for-Ā-men ō-VAL-ē), an opening between the atria that bypasses the lungs in fetal circulation

213

shock

Circulatory failure resulting in an inadequate supply of blood to the tissues. Cardiogenic shock is caused by heart failure; hypovolemic shock is caused by a loss of blood volume; septic shock is caused by bacterial infection

214

sinus rhythm

A normal heart rhythm originating from the sinoatrial (SA) node

215

stenosis

Constriction or narrowing of an opening

216

stroke

See cerebrovascular accident

217

syncope

A temporary loss of consciousness caused by inadequate blood flow to the brain; fainting

218

tachycardia

An abnormally rapid heart rate, usually over 100 bpm

219

thrombophlebitis

Inflammation of a vein associated with formation of a blood clot

220

thrombosis

Development of a blood clot within a vessel

221

thrombus

A blood clot that forms within a blood vessel (root: thromb/o)

222

varicose vein

A twisted and swollen vein resulting from breakdown of the valves, pooling of blood, and chronic dilatation of the vessel (root: varic/o); also called varix (VAR-iks) or varicosity (var-i-KOS-i-tē)

223

angioplasty

A procedure that reopens a narrowed vessel and restores blood flow. Commonly accomplished by surgically removing plaque, inflating a balloon within the vessel, or installing a device (stent) to keep the vessel open

224

artificial pacemaker

A battery-operated device that generates electrical impulses to regulate the beating of the heart. It may be external or implanted, may be designed to respond to need, and may have the capacity to prevent tachycardia

225

cardiopulmonary resuscitation (CPR)

Restoration of cardiac output and pulmonary ventilation after cardiac arrest using artificial respiration and chest compression or cardiac massage

226

cardioversion

Correction of an abnormal cardiac rhythm. May be accomplished pharmacologically, with antiarrhythmic drugs, or by application of electric current (see defibrillation)

227

coronary angiography

Radiographic study of the coronary arteries after introduction of an opaque dye by means of a catheter

228

coronary artery bypass graft (CABG)

Surgical creation of a shunt to bypass a blocked coronary artery. The aorta is connected to a point past the obstruction with another vessel or a piece of another vessel, usually the left internal mammary artery or part of the leg's saphenous vein

229

creatine kinase MB (CK-MB)

Enzyme released in increased amounts from cardiac muscle cells following myocardial infarction (MI). Serum assays help diagnose MI and determine the extent of muscle damage

230

defibrillation

Use of an electronic device (defibrillator) to stop fibrillation by delivering a brief electric shock to the heart. The shock may be delivered to the surface of the chest, as by an automated external defibrillator (AED), or directly into the heart through wire leads, using an implantable cardioverter defibrillator (ICD)

231

echocardiography (ECG)

A noninvasive method that uses ultrasound to visualize internal cardiac structures

232

lipoprotein

A compound of protein with lipid. Lipoproteins are classified according to density as very low density (VLDL), low density (LDL), and high density (HDL). Relatively higher levels of HDLs have been correlated with health of the cardiovascular system

233

percutaneous transluminal coronary angioplasty (PTCA)

Dilatation of a sclerotic blood vessel by means of a balloon catheter inserted into the vessel and then inflated to flatten plaque against the artery wall

234

stent

A small metal device in the shape of a coil or slotted tube that is placed inside an artery to keep the vessel open after balloon angioplasty

235

stress test

Evaluation of physical fitness by continuous ECG monitoring during exercise. In a thallium stress test, a radioactive isotope of thallium is administered to trace blood flow through the heart during exercise

236

troponin (Tn)

A protein in muscle cells that regulates contraction. Increased serum levels, primarily in the forms TnT and TnI, indicate recent myocardial infarction (MI)

237

appendix

A small, fingerlike mass of lymphoid tissue attached to the first part of the large intestine

238

lymph

The thin plasmalike fluid that drains from the tissues and is transported in lymphatic vessels (root: lymph/o)

239

lymph node

A small mass of lymphoid tissue along the path of a lymphatic vessel that filters lymph (root: lymphaden/o)

240

lymphatic system

The system that drains fluid and proteins from the tissues and returns them to the bloodstream. This system also participates in immunity and aids in absorption of fats from the digestive tract

241

Peyer patches

Aggregates of lymphoid tissue in the lining of the intestine

242

right lymphatic duct

The lymphatic duct that drains fluid from the upper right side of the body

243

spleen

A large reddish-brown organ in the upper left region of the abdomen. It filters blood and destroys old red blood cells (root: splen/o)

244

thoracic duct

The lymphatic duct that drains fluid from the upper left side of the body and all of the lower body/ left lymphatic duct

245

thymus gland

A gland in the upper part of the chest beneath the sternum. It functions in immunity (root: thym/o).

246

tonsils

Small masses of lymphoid tissue located in regions of the throat (pharynx)

247

lymphadenitis

Inflammation and enlargement of lymph nodes, usually as a result of infection

248

lymphangiitis

Inflammation of lymphatic vessels as a result of bacterial infection. Appears as painful red streaks under the skin. (Also spelled lymphangitis)

249

lymphedema

Swelling of tissues with lymph caused by obstruction or excision of lymphatic vessels

250

lymphoma

Any neoplastic disease of lymphoid tissue

251

apical pulse

Pulse felt or heard over the apex of the heart. It is measured in the fifth left intercostal space (between the ribs) about 8 to 9 cm from the midline

252

cardiac output

The amount of blood pumped from the right or left ventricle per minute

253

Korotkoff sounds

Arterial sounds heard with a stethoscope during determination of blood pressure with a cuff

254

perfusion

The passage of fluid, such as blood, through an organ or tissue

255

precordium

The anterior region over the heart and the lower part of the thorax; adjective, precordial

256

pulse pressure

The difference between systolic and diastolic pressure

257

stroke volume

The amount of blood ejected by the left ventricle with each beat

258

Valsalva maneuver

Bearing down, as in childbirth or defecation, by attempting to exhale forcefully with the nose and throat closed. This action has an effect on the cardiovascular system

259

bruit

An abnormal sound heard in auscultation

260

cardiac tamponade

Pathologic accumulation of fluid in the pericardial sac. May result from pericarditis or injury to the heart or great vessels.

261

ectopic beat

A heartbeat that originates from some part of the heart other than the SA node

262

extrasystole

Premature contraction of the heart that occurs separately from the normal beat and originates from a part of the heart other than the SA node

263

flutter

Very rapid (200 to 300 bpm) but regular contractions, as in the atria or the ventricles

264

hypotension

A condition of lower-than-normal blood pressure

265

intermittent claudication

Pain in a muscle during exercise caused by inadequate blood supply. The pain disappears with rest

266

mitral valve prolapse

Movement of the cusps of the mitral valve into the left atrium when the ventricles contract

267

occlusive vascular disease

Arteriosclerotic disease of the vessels, usually peripheral vessels

268

palpitation

A sensation of abnormally rapid or irregular heartbeat

269

pitting edema

Edema that retains the impression of a finger pressed firmly into the skin

270

polyarteritis nodosa

Potentially fatal collagen disease causing inflammation of small visceral arteries. Symptoms depend on the organ affected

271

Raynaud disease

A disorder characterized by abnormal constriction of peripheral vessels in the arms and legs on exposure to cold

272

regurgitation

A backward flow, such as the backflow of blood through a defective valve

273

stasis

Stoppage of normal flow, as of blood or urine. Blood stasis may lead to dermatitis and ulcer formation

274

subacute bacterial endocarditis (SBE)

Growth of bacteria in a heart or valves previously damaged by rheumatic fever

275

tetralogy of Fallot

A combination of four congenital heart abnormalities: pulmonary artery stenosis, interventricular septal defect, displacement of the aorta to the right, and right ventricular hypertrophy

276

thromboangiitis obliterans

Inflammation and thrombus formation resulting in occlusion of small vessels, especially in the legs. Most common in young men and correlated with heavy smoking. Thrombotic occlusion of leg vessels may lead to gangrene of the feet. Patients show a hypersensitivity to tobacco. Also called Buerger disease

277

vegetation

Irregular outgrowths of bacteria on the heart valves; associated with rheumatic fever

278

Wolff–Parkinson–White syndrome (WPW)

A cardiac arrhythmia consisting of tachycardia and a premature ventricular beat caused by an alternative conduction pathway

279

cardiac catheterization

Passage of a catheter into the heart through a vessel to inject a contrast medium for imaging, diagnosing abnormalities, obtaining samples, or measuring pressure

280

central venous pressure (CVP)

Pressure in the superior vena cava

281

cineangiocardiography

The photographic recording of fluoroscopic images of the heart and large vessels using motion picture techniques

282

computed tomography angiography (CTA)

Method for imaging the interior of arteries using computed tomography; uses less dye and is less invasive than standard angiography

283

Doppler echocardiography

An imaging method used to study the rate and pattern of blood flow

284

heart scan

Imaging of the heart after injection of a radioactive isotope. The PYP (pyrophosphate) scan using technetium-99m (99mTc) is used to test for myocardial infarction because the isotope is taken up by damaged tissue. The MUGA (multigated acquisition) scan gives information on heart function

285

Holter monitor

A portable device that can record up to 24 hours of an individual's ECG readings during normal activity

286

homocysteine

An amino acid in the blood that at higher-than-normal levels is associated with increased risk of cardiovascular disease

287

phlebotomist

Technician who specializes in drawing blood

288

phonocardiography

Electronic recording of heart sounds

289

plethysmography

Measurement of changes in the size of a part based on the amount of blood contained in or passing through it. Impedance plethysmography measures changes in electrical resistance and is used in the diagnosis of deep vein thrombosis

290

pulmonary capillary wedge pressure (PCWP)

Pressure measured by a catheter in a branch of the pulmonary artery. It is an indirect measure of pressure in the left atrium

291

Swan–Ganz catheter

A cardiac catheter with a balloon at the tip that is used to measure pulmonary arterial pressure. It is flow-guided through a vein into the right side of the heart and then into the pulmonary artery transesophageal

292

echocardiography (TEE)

Use of an ultrasound transducer placed endoscopically into the esophagus to obtain images of the heart

293

triglycerides

Simple fats that circulate in the bloodstream

294

ventriculography

X-ray study of the ventricles of the heart after introduction of an opaque dye by means of a catheter

295

atherectomy

Removal of atheromatous plaque from the lining of a vessel. May be done by open surgery or through the lumen of the vessel

296

commissurotomy

Surgical incision of a scarred mitral valve to increase the size of the valve opening

297

embolectomy

Surgical removal of an embolus

298

intraaortic balloon pump (IABP)

A mechanical assist device that consists of an inflatable balloon pump inserted through the femoral artery into the thoracic aorta. It inflates during diastole to improve coronary circulation and deflates before systole to allow blood ejection from the heart

299

left ventricular assist device (LVAD)

A pump that takes over the function of the left ventricle in delivering blood into the systemic circuit. These devices are used to assist patients awaiting heart transplantation or those who are recovering from heart failure

300

angiotensin-converting enzyme (ACE) inhibitor

A drug that lowers blood pressure by blocking the formation in the blood of angiotensin II, a substance that normally acts to increase blood pressure

301

angiotensin receptor blocker (ARB)

A drug that blocks tissue receptors for angiotensin II; angiotensin II receptor antagonist

302

antiarrhythmic agent

A drug that regulates the rate and rhythm of the heartbeat

303

agranulocytes

A white blood cell that does not have visible granules in its cytoplasm. Agranulocytes include lymphocytes and monocytes

304

albumin

A simple protein found in blood plasma

305

antibody

A protein produced in response to and interacting specifically with an antigen

306

antigen

A substance that induces the formation of an antibody

307

B cell

A lymphocyte that matures in lymphoid tissue and is active in producing antibodies; B lymphocyte (LIM-fō-sīt)

308

band cell

An immature neutrophil with a nucleus in the shape of a band; also called a stab cell. Band cell counts are used to trace infections and other diseases

309

basophil

A granular leukocyte that stains with basic dyes; active in allergic reactions

310

blood

The fluid that circulates in the cardiovascular system (root: hem/o, hemat/o)

311

coagulation

Blood clotting

312

cross-matching

Testing the compatibility of donor and recipient blood in preparation for a transfusion. Donor red cells are mixed with recipient serum, and red cells of the recipient are mixed with donor serum to look for an immunologic reaction. Similar tests are done on tissues before transplantation

313

electrolyte

A substance that separates into charged particles (ions) in solution; a salt. Term also applied to ions in body fluids

314

eosinophil

A granular leukocyte that stains with acidic dyes; active in allergic reactions and defense against parasites

315

erythrocyte

A red blood cell (root: erythr/o, erythrocyt/o)

316

erythropoietin (EPO)

A hormone produced in the kidneys that stimulates red blood cell production in the bone marrow. This hormone is now made by genetic engineering for clinical use

317

fibrin

The protein that forms a clot in the process of blood coagulation

318

fibrinogen

The inactive precursor of fibrin

319

formed elements

The cellular components of blood

320

gamma globulin

The fraction of the blood plasma that contains antibodies; given for passive transfer of immunity

321

granulocytes

A white blood cell that has visible granules in its cytoplasm. Granulocytes include neutrophils, basophils, and eosinophils

322

hemoglobin (Hb, Hgb)

The iron-containing pigment in red blood cells that transports oxygen

323

hemostasis

The stoppage of bleeding

324

immunity

The state of being protected against a specific disease (root: immun/o)

325

immunoglobulin (Ig)

An antibody. Immunoglobulins fall into five classes, each abbreviated with a capital letter: IgG, IgM, IgA, IgD, IgE

326

leukocyte

A white blood cell (root: leuk/o, leukocyt/o)

327

lymphocyte

An agranular leukocyte active in immunity (T cells and B cells); found in both the blood and in lymphoid tissue (root: lymph/o, lymphocyt/o)

328

megakaryocyte

A large bone marrow cell that fragments to release platelets

329

macrophage

A phagocytic cell derived from a monocyte; usually located within the tissues. Macrophages process antigens for T cells

330

monocyte

An agranular phagocytic leukocyte

331

neutrophil

A granular leukocyte that stains with acidic or basic dyes. The most numerous of the white blood cells. A type of phagocyte

332

phagocytosis

The engulfing of foreign material by white blood cells

333

plasma

The liquid portion of the blood

334

plasma cell

A mature form of a B cell that produces antibodies

335

platelet

A formed element of the blood that is active in hemostasis; a thrombocyte (root: thrombocyt/o)

336

serum

The fraction of the plasma that remains after blood coagulation; it is the equivalent of plasma without its clotting factors (plural: sera, serums)

337

T cell

A lymphocyte that matures in the thymus gland and attacks foreign cells directly; T lymphocyte

338

thrombocyte

A blood platelet (root: thrombocyt/o)

339

AIDS (acquired immunodeficiency syndrome)

Failure of the immune system caused by infection with HIV (human immunodeficiency virus). The virus infects certain T cells and thus interferes with immunity

340

allergen

A substance that causes an allergic response

341

allergy

Hypersensitivity

342

anaphylactic reaction

An exaggerated allergic reaction to a foreign substance (root phylaxis means. “protection”). It may lead to death caused by circulatory collapse, and respiratory distress if untreated. Also called anaphylaxis

343

anemia

A deficiency in the amount of hemoglobin in the blood; may result from blood loss, malnutrition, a hereditary defect, environmental factors, and other causes

344

angioedema

A localized edema with large hives (wheals) similar to urticaria but involving deeper layers of the skin and subcutaneous tissue

345

aplastic anemia

Anemia caused by bone marrow failure resulting in deficient blood cell production, especially of red cells; pancytopenia

346

autoimmune disease

A condition in which the immune system produces antibodies against an individual's own tissues (prefix auto means “self”)

347

Cooley anemia

A form of thalassemia (hereditary anemia) which affects production of the β (beta) hemoglobin chain; thalassemia major

348

delayed hypersensitivity reaction

An allergic reaction involving T cells that takes at least 12 hours to develop. Examples are various types of contact dermatitis, such as poison ivy or poison oak; the tuberculin reaction (test for TB); and rejections of transplanted tissue

349

disseminated intravascular coagulation (DIC)

Widespread formation of clots in the microscopic vessels; may be followed by bleeding caused by depletion of clotting factors

350

ecchymosis

A collection of blood under the skin caused by leakage from small vessels (root chym means “juice”)

351

hemolysis

The rupture of red blood cells and the release of hemoglobin (adjective: hemolytic)

352

hemophilia

A hereditary blood disease caused by lack of a clotting factor and resulting in abnormal bleeding

353

HIV (human immunodeficiency virus)

The virus that causes AIDS

354

Hodgkin disease

A neoplastic disease of unknown cause that involves the lymph nodes, spleen, liver, and other tissues; characterized by the presence of giant Reed-Sternberg cells

355

hypersensitivity

An immunologic reaction to a substance that is harmless to most people; allergy

356

immunodeficiency

A congenital or acquired failure of the immune system to protect against disease

357

intrinsic factor

A substance produced in the stomach that aids in the absorption of vitamin B12, necessary for the manufacture of red blood cells. Lack of intrinsic factor causes pernicious anemia

358

Kaposi sarcoma

Cancerous lesion of the skin and other tissues, seen most often in patients with AIDS

359

leukemia

Malignant overgrowth of immature white blood cells; may be chronic or acute; may affect bone marrow (myelogenous leukemia) or lymphoid tissue (lymphocytic leukemia)

360

lymphadenopathy

Any disease of the lymph nodes

361

multiple myeloma

A tumor of the blood-forming tissue in bone marrow

362

non-Hodgkin lymphoma (NHL)

A widespread malignant disease of lymph nodes that involves lymphocytes. It differs from Hodgkin disease in that giant Reed-Sternberg cells are absent.

363

Philadelphia chromosome (Ph)

An abnormal chromosome found in the cells of most individuals with chronic granulocytic (myelogenous) leukemia

364

pernicious anemia

Anemia caused by failure of the stomach to produce intrinsic factor, a substance needed for the absorption of vitamin B12. This vitamin is required for the formation of erythrocytes.

365

petechiae

Pinpoint, flat, purplish-red spots caused by bleeding within the skin or mucous membrane (singular: petechia)

366

purpura

A condition characterized by hemorrhages into the skin, mucous membranes, internal organs, and other tissues (from Greek word meaning “purple”). Thrombocytopenic purpura is caused by a deficiency of platelets

367

sideroblastic anemia

Anemia caused by inability to use available iron to manufacture hemoglobin. The excess iron precipitates in normoblasts (developing red blood cells)

368

Sjögren syndrome

An autoimmune disease involving dysfunction of the exocrine glands and affecting secretion of tears, saliva, and other body fluids. Deficiency leads to dry mouth, tooth decay, corneal damage, eye infections, and difficulty in swallowing

369

sickle cell anemia

A hereditary anemia caused by the presence of abnormal hemoglobin. Red blood cells become sickle shaped and interfere with normal blood flow to the tissues. Most common in black populations of West African descent

370

splenomegaly

Enlargement of the spleen

371

systemic lupus erythematosus

Inflammatory connective tissue disease affecting the skin and multiple organs. Patients are sensitive to light and may have a red butterfly-shaped rash over the nose and cheeks

372

systemic sclerosis

A diffuse disease of connective tissue that may involve any system causing inflammation, degeneration, and fibrosis. Also called scleroderma because it causes thickening of the skin

373

thalassemia

A group of hereditary anemias mostly found in populations of Mediterranean descent (the name comes from the Greek word for “sea”)

374

thrombocytopenia

A deficiency of thrombocytes (platelets) in the blood

375

urticaria

A skin reaction consisting of round, raised eruptions (wheals) with itching; hives

376

adrenaline

See epinephrine

377

CD4+ T lymphocyte count

A count of the T cells that have the CD4 receptors for the AIDS virus (HIV). A count of less than 200/µL of blood signifies severe immunodeficiency.

378

epinephrine

A powerful stimulant produced by the adrenal gland and sympathetic nervous system. Activates the cardiovascular, respiratory, and other systems needed to meet stress. Used as a drug to treat severe allergic reactions and shock. Also called adrenaline

379

reticulocyte counts

Blood counts of reticulocytes, a type of immature red blood cell; reticulocyte counts are useful in diagnosis to indicate the rate of erythrocyte formation

380

Reed-Sternberg cells

Giant cells that are characteristic of Hodgkin disease. They usually have two large nuclei and are surrounded by a halo

381

agglutination

The clumping of cells or particles in the presence of specific antibodies

382

bilirubin

A pigment derived from the breakdown of hemoglobin. It is eliminated by the liver in bile

383

complement

A group of plasma enzymes that interacts with antibodies

384

corpuscle

A small mass or body. A blood corpuscle is a blood cell

385

hemopoietic stem cell

A primitive bone marrow cell that gives rise to all varieties of blood cells

386

heparin

A substance found throughout the body that inhibits blood coagulation; an anticoagulant

387

plasmin

An enzyme that dissolves clots; also called fibrinolysin

388

thrombin

The enzyme derived from prothrombin that converts fibrinogen to fibrin

389

agranulocytosis

A condition involving a decrease in the number of granulocytes in the blood; also called granulocytopenia

390

erythrocytosis

Increase in the number of red cells in the blood; may be normal, such as to compensate for life at high altitudes, or abnormal, such as in cases of pulmonary or cardiac disease

391

Fanconi syndrome

Congenital aplastic anemia that appears between birth and 10 years of age; may be hereditary or caused by damage before birth, as by a virus

392

graft-versus-host reaction (GVHR)

An immunologic reaction of transplanted lymphocytes against tissues of the host; a common complication of bone marrow transplantation.

393

Hairy cell leukemia

A form of leukemia in which cells have filaments, making them look “hairy”

394

hematoma

A localized collection of blood, usually clotted, caused by a break in a blood vessel

395

hemolytic disease of the newborn (HDN)

Disease that results from incompatibility between the blood of a mother and her fetus, usually involving Rh factor. An Rh-negative mother produces antibody to an Rh-positive fetus that, in later pregnancies, will destroy the red cells of an Rh-positive fetus. The problem is usually avoided by treating the mother with antibodies to remove the Rh antigen; erythroblastosis fetalis

396

hemosiderosis

A condition involving the deposition of an iron-containing pigment (hemosiderin) mainly in the liver and the spleen. The pigment comes from hemoglobin released from disintegrated red blood cells

397

idiopathic thrombocytopenic purpura (ITP)

A clotting disorder caused by destruction of platelets that usually follows a viral illness. Causes petechiae and hemorrhages into the skin and mucous membranes

398

infectious mononucleosis

An acute infectious disease caused by Epstein–Barr virus (EBV). Characterized by fever, weakness, lymphadenopathy, hepatosplenomegaly, and atypical lymphocytes (resembling monocytes)

399

hemolytic disease of the newborn (HDN)

Disease that results from incompatibility between the blood of a mother and her fetus, usually involving Rh factor. An Rh-negative mother produces antibody to an Rh-positive fetus that, in later pregnancies, will destroy the red cells of an Rh-positive fetus. The problem is usually avoided by treating the mother with antibodies to remove the Rh antigen; erythroblastosis fetalis

400

hemosiderosis

A condition involving the deposition of an iron-containing pigment (hemosiderin) mainly in the liver and the spleen. The pigment comes from hemoglobin released from disintegrated red blood cells

401

idiopathic thrombocytopenic purpura (ITP)

A clotting disorder caused by destruction of platelets that usually follows a viral illness. Causes petechiae and hemorrhages into the skin and mucous membranes

402

infectious mononucleosis

An acute infectious disease caused by Epstein–Barr virus (EBV). Characterized by fever, weakness, lymphadenopathy, hepatosplenomegaly, and atypical lymphocytes (resembling monocytes)

403

polycythemia vera

A condition in which overactive bone marrow produces too many red blood cells. These interfere with circulation and promote thrombosis and hemorrhage. Treated by blood removal. Also called erythremia, Vasquez–Osler disease

404

septicemia

Presence of microorganisms in the blood

405

spherocytic anemia

Hereditary anemia in which red blood cells are round instead of disk-shaped and rupture (hemolyze) excessively

406

thrombotic thrombocytopenic purpura (TTP)

An often fatal disorder in which multiple clots form in blood vessels

407

von Willebrand disease

A hereditary bleeding disease caused by lack of von Willebrand factor, a substance necessary for blood clotting

408

Bence Jones protein

A protein that appears in the urine of patients with multiple myeloma

409

Coombs test

A test for detection of antibodies to red blood cells such as appear in cases of autoimmune hemolytic anemias

410

electrophoresis

Separation of particles in a liquid by application of an electrical field; used to separate components of blood.

411

ELISA

Enzyme-linked immunosorbent assay. A highly sensitive immunologic test used to diagnose HIV infection, hepatitis, and Lyme disease, among others

412

monoclonal antibody

A pure antibody produced in the laboratory; used for diagnosis and treatment

413

pH

A scale that measures the relative acidity or alkalinity of a solution. Represents the amount of hydrogen ion in the solution

414

Schilling test

Test used to determine absorption of vitamin B12 by measuring excretion of radioactive B12 in the urine. Used to distinguish pernicious from nutritional anemia

415

seroconversion

The appearance of antibodies in the serum in response to a disease or an immunization

416

Western blot assay

A very sensitive test used to detect small amounts of antibodies in the blood

417

Wright stain

A commonly used blood stain

418

anticoagulant

An agent that prevents or delays blood coagulation

419

antihistamine

A drug that counteracts the effects of histamine and is used to treat allergic reactions

420

apheresis

A procedure in which blood is withdrawn, a portion is separated and retained, and the remainder is returned to the donor. Apheresis may be used as a suffix with a root meaning the fraction retained, such as plasmapheresis, leukapheresis

421

autologous blood

A person's own blood. May be donated in advance of surgery and transfused if needed

422

cryoprecipitate

A sediment obtained by cooling. The fraction obtained by freezing blood plasma contains clotting factors

423

desensitization

Treatment of allergy by small injections of the offending allergen. This causes an increase of antibody to destroy the antigen rapidly on contact

424

homologous blood

Blood from animals of the same species, such as human blood used for transfusion from one person to another. Blood used for transfusions must be compatible with the blood of the recipient

425

immunosuppression

Depression of the immune response. May be correlated with disease but also may be induced therapeutically to prevent rejection in cases of tissue transplantation

426

protease inhibitor

An anti-HIV drug that acts by inhibiting an enzyme the virus needs to multiply

427

adrenal gland

A gland on the superior surface of the kidney. The outer region (cortex) secretes steroid hormones; the inner region (medulla) secretes epinephrine (adrenaline) (root: adren/o)

428

endocrine

Pertaining to a ductless gland that secretes directly into the blood

429

hormone

A secretion of an endocrine gland. A substance that travels in the blood and has a regulatory effect on tissues, organs, or glands

430

hypophysis

The pituitary gland (root: hypophys); named from hypo, meaning “below,” and physis, meaning “growing,” because the gland grows below the hypothalamus

431

hypothalamus

A portion of the brain that controls the pituitary gland and is active in maintaining homeostasis

432

pancreatic islets

Clusters of endocrine cells in the pancreas that secrete hormones to regulate sugar metabolism; also called islets of Langerhans or islet cells (root insul/o means “island”)

433

parathyroid glands

Small endocrine glands on the posterior thyroid that act to increase blood calcium levels; there are usually four to six parathyroid glands (root: parathyr/o, parathyroid/o); the name literally means “near the thyroid”

434

pineal gland

A small gland in the brain. Appears to regulate mood, daily rhythms, and sexual development in response to environmental light. Secretes the hormone melatonin

435

pituitary gland

A small endocrine gland at the base of the brain. The anterior lobe secretes growth hormone and hormones that stimulate other glands; the posterior lobe releases ADH and oxytocin manufactured in the hypothalamus

436

prostaglandins

A group of hormones produced throughout the body that have a variety of effects, including stimulation of uterine contractions and regulation of blood pressure, blood clotting, and inflammation

437

receptor

A site on the cell membrane or within the cell to which a substance, such as a hormone, attaches

438

steroid hormone

A hormone made from lipids and including the sex hormones and the hormones of the adrenal cortex

439

target tissue

The specific tissue on which a hormone acts; may also be called the target organ

440

thyroid gland

An endocrine gland on either side of the larynx and upper trachea. It secretes hormones that affect metabolism and growth and a hormone (calcitonin) that regulates calcium balance (root: thyr/o, thyroid/o).

441

acromegaly

Overgrowth of bone and soft tissue, especially in the hands, feet, and face, caused by an excess of growth hormone in an adult. The name comes from acro meaning “extremity” and megal/o meaning “enlargement”

442

Addison disease

A disease resulting from deficiency of adrenocortical hormones. It is marked by darkening of the skin, weakness, and alterations in salt and water balance

443

adenoma

A neoplasm of a gland

444

adult hypothyroidism

A condition caused by hypothyroidism in an adult. There is dry, waxy swelling, most notable in the face; formerly called myxedema

445

Cushing disease

Overactivity of the adrenal cortex resulting from excess production of ACTH by the pituitary

446

Cushing syndrome

A condition resulting from an excess of hormones from the adrenal cortex. It is associated with obesity, weakness, hyperglycemia, hypertension, and hirsutism (excess hair growth)

447

diabetes insipidus

A disorder caused by insufficient release of ADH from the posterior pituitary. It results in excessive thirst and production of large amounts of very dilute urine. The word insipidus means “tasteless,” referring to the dilution of the urine

448

diabetes mellitus

A disorder of glucose metabolism caused by deficiency of insulin production or failure of the tissues to respond to insulin. Type 1 results from autoimmune destruction of pancreatic islet cells; it generally appears in children and requires insulin administration. Type 2 generally occurs in obese adults; it is treated with diet, exercise, drugs to improve insulin production or activity, and sometimes insulin. The word mellitus comes from the Latin root for honey, referring to the sugar content of the urine

449

exophthalmos

Protrusion of the eyeballs, as seen in Graves disease

450

gigantism

Overgrowth caused by an excess of growth hormone from the pituitary during childhood; also called giantism

451

glycated hemoglobin (HbA1c) test

A test that measures the binding of glucose to hemoglobin during the lifespan of a red blood cell. It reflects the average blood glucose level over two to three months and is useful in evaluating long-term therapy for diabetes mellitus. Also called A1c test

452

glycosuria

Excess sugar in the urine

453

goiter

Enlargement of the thyroid gland. May be toxic or nontoxic. Simple (nontoxic) goiter is caused by iodine deficiency

454

Graves disease

An autoimmune disease resulting in hyperthyroidism. A prominent symptom is exophthalmos (protrusion of the eyeballs). Also called diffuse toxic goiter

455

hyperglycemia

Excess glucose in the blood

456

hypoglycemia

Abnormally low level of glucose in the blood

457

insulin shock

A condition resulting from an overdose of insulin, causing hypoglycemia

458

infantile hypothyroidism

A condition caused by congenital lack of thyroid secretion and marked by arrested physical and mental development; also called congenital hypothyroidism

459

ketoacidosis

Acidosis (increased acidity of body fluids) caused by an excess of ketone bodies, as in diabetes mellitus; diabetic acidosis

460

metabolic syndrome

A state of hyperglycemia caused by cellular resistance to insulin, as seen in type 2 diabetes, in association with other metabolic disorders; syndrome X or insulin resistance syndrome

461

panhypopituitarism

Underactivity of the entire pituitary gland

462

tetany

Irritability and spasms of muscles; may be caused by low blood calcium and other factors

463

sella turcica

A saddle-shaped depression in the sphenoid bone that contains the pituitary gland (literally means “Turkish saddle”)

464

sphenoid bone

A bone at the base of the skull that houses the pituitary gland

465

adrenogenital syndrome

Condition caused by overproduction of androgens from the adrenal cortex, resulting in masculinization; may be congenital or acquired, usually as a result of an adrenal tumor

466

Conn syndrome

Hyperaldosteronism caused by an adrenal tumor

467

craniopharyngioma

A tumor of the pituitary gland

468

Hashimoto disease

A chronic thyroiditis of autoimmune origin

469

impaired glucose tolerance (IGT)

High blood glucose levels after glucose intake that may signal borderline diabetes mellitus

470

ketosis

Accumulation of ketone bodies, such as acetone, in the body. Usually results from deficiency or faulty metabolism of carbohydrates, as in cases of diabetes mellitus and starvation

471

multiple endocrine neoplasia (MEN)

A hereditary disorder that causes tumors in several endocrine glands; classified according to the combination of glands involved

472

pheochromocytoma

A usually benign tumor of the adrenal medulla or other structures containing chromaffin cells (cells that stain with chromium salts); phe/o means “brown” or “dusky.” The adrenal tumor causes increased production of epinephrine.

473

pituitary apoplexy

Sudden massive hemorrhage and degeneration of the pituitary gland associated with a pituitary tumor. Common symptoms include severe headache, visual problems, and loss of consciousness

474

seasonal affective disorder (SAD)

A mood disorder with lethargy, depression, excessive need for sleep, and overeating that generally occurs in winter. Thought to be related to melatonin levels as influenced by environmental light

475

Simmonds disease

Hypofunction of the anterior pituitary (panhypopituitarism), usually because of an infarction; pituitary cachexia (ka-KEK-sē-a)

476

thyroid storm

A sudden onset of the symptoms of thyrotoxicosis occurring in patients with hyperthyroidism who are untreated or poorly treated. May be brought on by illness or trauma. Also called thyroid crisis

477

thyrotoxicosis

Condition resulting from overactivity of the thyroid gland. Symptoms include anxiety, irritability, weight loss, and sweating. The main example of thyrotoxicosis is Graves disease

478

von Recklinghausen disease

Degeneration of bone caused by excess production of parathyroid hormone. Also called Recklinghausen disease of bone

479

fasting plasma glucose (FPG)

Measurement of glucose in the blood after a fast of at least eight hours. A reading greater than or equal to126 mg/dL indicates diabetes. Also called fasting blood glucose (FBG) or fasting blood sugar (FBS)

480

free thyroxine index (FTI, T7)

Calculation based on the amount of T4 present and T3 uptake, used to diagnose thyroid dysfunction

481

oral glucose tolerance test (OGTT)

Measurement of glucose levels in blood plasma after administration of a challenge dose of glucose to a fasting patient. Used to measure patient's ability to metabolize glucose. A value greater than or equal to 200 mg/dL in the two-hour sample indicates diabetes

482

radioactive iodine uptake test (RAIU)

A test that measures thyroid uptake of radioactive iodine as an evaluation of thyroid function

483

radioimmunoassay (RIA)

A method of measuring very small amounts of a substance, especially hormones, in blood plasma using radioactively labeled hormones and specific antibodies

484

thyroid scan

Visualization of the thyroid gland after administration of radioactive iodine

485

thyroxine

binding globulin (TBG) test - Test that measures the main protein that binds T4 in the blood

486

transsphenoidal adenomectomy

Removal of a pituitary tumor through the sphenoid sinus (space in the sphenoid bone)