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depressant

(Encyclopedia)depressant, any one of various substances that diminish functional activity, usually by depressing the nervous system. Barbiturates, sedatives, alcohol, and meprobamate are all depressants. Depressant...

dogwood

(Encyclopedia)dogwood or cornel kôrˈnəl [key], shrub or tree of the genus Cornus, chiefly of north temperate and tropical mountain regions, characteristically having an inconspicuous flower surrounded by large, ...

DDT

(Encyclopedia)DDT or 2,2-bis(p-chlorophenyl)-1,1,1,-trichloroethane, chlorinated hydrocarbon compound used as an insecticide. First introduced during the 1940s, it killed insects that spread disease and fed on crop...

snail

(Encyclopedia)snail, name commonly used for a gastropod mollusk with a shell. Included in the thousands of species are terrestrial, freshwater, and marine forms. Some eat both plant and animal matter; others eat on...

saiga

(Encyclopedia)saiga, sīˈgə [key], Eurasian antelope, Saiga tatarica, found in steppes, grasslands, and semidesert regions in Kazakhstan, Mongolia, and Kalmykia, Russia. Noted for its large, flexible, and inflata...

toxemia

(Encyclopedia)toxemia tŏksēˈmēə [key], disease state caused by the presence in the blood of bacterial toxins or other harmful substances. The effects of the bacterial toxins known as endotoxins are relatively ...

trichina

(Encyclopedia)trichina trĭkīˈnə [key], common name for species of roundworm of the phylum Nematoda. The species Trichinella spiralis is an important parasite, occurring in rats, pigs, and man, and is responsibl...

osteopathy

(Encyclopedia)osteopathy ŏstēŏpˈəthē [key], practice of therapy based on manipulation of bones and muscles. This school of medicine, founded by A. T. Still in 1874, maintains that the normal body produces for...

neostigmine

(Encyclopedia)neostigmine nēˌōstĭgˈmēn, –mĭn [key], drug used to mimic the effects of stimulation of the parasympathetic nervous system. Along with several other drugs that have a similar mode of action, i...

tetany

(Encyclopedia)tetany tĕtˈənē [key], condition of mineral imbalance in the body that results in severe muscle spasms. Tetany occurs when the concentration of calcium ions (Ca++) in extracellular fluids such as p...