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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...

oxpecker

(Encyclopedia)oxpecker, common name for an African starling of the genus Buphagus. Also known as tickbirds, oxpeckers have very short legs and sharp claws, which aid them in perching on the backs of large mammals, ...

histology

(Encyclopedia)histology hĭstŏlˈəjē [key], study of the groups of specialized cells called tissues that are found in most multicellular plants and animals. Histologists study the organization of tissues at all ...

humor

(Encyclopedia)humor, according to ancient theory, any of four bodily fluids that determined human health and temperament. Hippocrates postulated that an imbalance among the humors (blood, phlegm, yellow bile, and b...