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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...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...

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...

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...

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...

bloc, parliamentary

(Encyclopedia)bloc, parliamentary [Fr.,=block], group of legislators formed to support special interests. A bloc may form because of a specific issue and dissolve when that issue has been resolved, or it may have a...

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...

lobbying

(Encyclopedia)lobbying, practice and profession of influencing governmental decisions, carried out by agents who present the concerns of special interests to legislators and administrators. The term originated in t...