Porth's Essentials of Pathophysiology, 4e

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Glossary

Articulation  The place of connection or junction between two or more bones of a skeletal joint. Ascites  An abnormal accumulation of serous fluid in the peritoneal cavity. Asepsis  The condition of being free or freed from pathogenic microorganisms. Astereognosis  A neurologic disorder characterized by an inability to identify objects by touch. Asterixis  A motor disturbance characterized by a hand- flapping tremor, which results when the prolonged contraction of groups of muscles lapses intermittently. Ataxia  An abnormal condition characterized by an inability to coordinate voluntary muscular movement. Athetosis  A neuromuscular condition characterized by the continuous occurrence of slow, sinuous, writhing movements that are performed involuntarily. (Adjective: athetoid) Atopy  Genetic predisposition toward the development of hypersensitivity or an allergic reaction to common environmental allergens. Atresia  The absence or closure of a normal body ori- fice or tubular organ, such as the esophagus. Atrophy  A wasting or diminution of size, often accom- panied by a decrease in function, of a cell, tissue, or organ. Aura  A distinct subjective feeling, sensation, or motor phenomenon that precedes and marks the onset of an episode of a neurological condition, such as a migraine or epileptic seizure. Autocrine  A mode of hormone action in which a chem- ical messenger acts on the same cell that secretes it. Autophagy  Segregation of part of the cell’s own dam- aged cytoplasmic material within a vacuole and its disposal. Autosome  Any chromosome other than a sex chromosome. Axillary  Of or pertaining to the axilla, or armpit. Bacteremia  The presence of bacteria in the blood. Bactericide  An agent that destroys bacteria. (Adjective: bactericidal) Bacteriostat  An agent that inhibits bacterial growth. (Adjective: bacteriostatic) Ballismus  An abnormal condition characterized by violent flailing motions of the arms and, occasion- ally, the head, resulting from injury to or destruction of the subthalamic nucleus or its fiber connections. Baroreceptor  A type of sensory nerve ending, such as those found in the aorta and the carotid sinus, that is stimulated by changes in pressure. Basal  Pertaining to, situated at, or forming the base; or the fundamental or basic. Benign  Not malignant; or of the character that does not threaten health or life. Bipolar neuron  A nerve cell that has an afferent process at one end and an efferent process at the other end. Bolus  A rounded mass of food ready to swallow or such a mass passing through the gastrointestinal tract; or a concentrated mass of medicinal material or other pharmaceutical preparation injected all at once intravenously for diagnostic purposes.

Borborygmus  The rumbling, gurgling, or tinkling noise produced by the propulsion of gas through the intestine. Bruit  A sound or murmur heard while auscultating an organ or blood vessel, especially an abnormal one. Buccal  Pertaining to or directed toward the inside of the cheek. Buffer  A substance or group of substances that prevents change in the concentration of another chemical substance. Bulla  A thin-walled blister of the skin or mucous membranes greater than 5 mm in diameter contain- ing serous or seropurulent fluid. Bursa  A fluid-filled sac or saclike cavity situated in places in the tissues at which friction would other- wise develop, such as between certain tendons and the bones beneath them. Cachexia  A condition of general ill health and malnu- trition, marked by weakness and emaciation. Calculus  A stony mass formed within body tissues, usually composed of mineral salts. Capsid  The protein shell that envelops and protects the nucleic acid of a virus. Carcinogen  Any substance or agent that causes the development or increases the incidence of cancer. Carpal  Of or pertaining to the carpus, or wrist. Caseation  A form of tissue necrosis in which the tissue is changed into a dry, amorphous mass resembling crumbly cheese. Catabolism  A metabolic process through which living organisms break down complex substances to simple compounds, liberating energy for use in work, energy storage, or heat production. Catalyst  A substance that increases the velocity of a chemical reaction without being consumed by the process. Catecholamines  Any one of a group of biogenic amines having a sympathomimetic action and composed of a catechol molecule and the aliphatic portion of an amine. Caudal  Signifying an inferior position, toward the distal end of the spine. Cellulitis  An acute, diffuse, spreading, edematous inflammation of the deep subcutaneous tissues and sometimes muscle, characterized most commonly by an area of heat, redness, pain, and swelling, and occasionally by fever, malaise, chills, and headache. Cephalic  Of or pertaining to the head, or to the head end of the body. Cerumen  The waxlike secretion produced by vestigial apocrine sweat glands in the external ear canal. Cheilosis  A noninflammatory disorder of the lips and mouth characterized by chapping and fissuring. Chelate  A chemical compound composed of a central metal ion and an organic molecule with multiple bonds, arranged in ring formation, used especially in treatment of metal poisoning. Chemoreceptor  A sensory nerve cell activated by chemical stimuli; for example, a chemoreceptor in the carotid artery is sensitive to changes in the oxygen content in the blood and reflexly increases or decreases respiration and blood pressure.