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Beauvoir, Simone de

(Encyclopedia)Beauvoir, Simone de sēmônˈ də bōvwärˈ [key], 1908–86, French author. A leading exponent of existentialism, she is closely associated with Jean-Paul Sartre, with whom she had a life-long relat...

rhythm, biological

(Encyclopedia)rhythm, biological, or biorhythm, cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the env...

serum sickness

(Encyclopedia)serum sickness, hypersensitive response that occurs after injection of a large amount of foreign protein. The condition is named for the serum taken from horses or other animals immunized against a pa...

cortisol

(Encyclopedia)cortisol kôrˈtĭsôlˌ [key] or hydrocortisone, steroid hormone that in humans is the major circulating hormone of the cortex, or outer layer, of the adrenal gland. Like cortisone, cortisol is class...

colitis

(Encyclopedia)colitis, inflammation of the colon, or large intestine. The term “colitis” may be used to refer to any of a number of disorders involving the colon. Symptoms include diarrhea (often with blood and...

glutamine

(Encyclopedia)CE5 glutamine glo͞oˈtəmēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer occurs in mammalian protein. Its structure is identical t...

digitalis

(Encyclopedia)digitalis dĭjˌĭtălˈĭs [key], any of several chemically similar drugs used primarily to increase the force and rate of heart contractions, especially in damaged heart muscle. The effects of the d...

fatigue, in physiology

(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...

QAnon

(Encyclopedia) QAnon , a widely believed right-wing conspiracy theory. QAnon developed in the early years of Donald Trump’s presidency through the anonymous posts o...

quinine

(Encyclopedia)quinine kwīˈnīnˌ, kwĭnēnˈ [key], white crystalline alkaloid with a bitter taste. Before the development of more effective synthetic drugs such as quinacrine, chloroquine, and primaquine, quinin...