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antidiuretic hormone

(Encyclopedia)antidiuretic hormone ănˌtēdīyo͞orĕtˈĭk [key], polypeptide hormone secreted by the posterior pituitary gland. Its principal action is to regulate the amount of water excreted by the kidneys. An...

hernia

(Encyclopedia)hernia, protrusion of an internal organ or part of an organ through the wall of a body cavity. The hernia is enclosed by a sac formed by the lining of the cavity. It results from a weakness or rupture...

nitrogen mustard

(Encyclopedia)nitrogen mustard, any of various poisonous compounds originally developed for military use (see poison gas). Like mustard gas and lewisite, it is a vesicant (blistering agent). In the form of its crys...

plagues of Egypt

(Encyclopedia)plagues of Egypt, in the Bible, the plagues and other troubles brought on Egypt by God through the hands of Moses, because Pharaoh would not let the people of Israel go out of Egypt. The account, in t...

pigmentation

(Encyclopedia)pigmentation, name for the coloring matter found in certain plant and animal cells and for the color produced thereby. Pigmentation occurs in nearly all living organisms. Almost all plants synthesize ...

skin

(Encyclopedia)CE5 Cross section of skin skin, the flexible tissue (integument) enclosing the body of vertebrate animals. In humans and other mammals, the skin operates a complex organ of numerous structures (so...

dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

nicotine

(Encyclopedia)nicotine, C10H14N2, poisonous, pale yellow, oily liquid alkaloid with a pungent odor and an acrid taste. It turns brown on exposure to air. Nicotine, a naturally occurring constituent of tobacco, is t...

heatstroke

(Encyclopedia)heatstroke, profound disturbance of the heat-regulating mechanism of the body, also known as sunstroke. It is characterized by extremely high body temperatures and sometimes by convulsions and coma. T...

Furchgott, Robert Francis

(Encyclopedia)Furchgott, Robert Francis, 1916–2009, American biochemist, b. Charleston, S.C., Ph.D. Northwestern Univ., 1940. Furchgott spent his entire career as a professor (1956–89) at the State Univ. of New...