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valine

(Encyclopedia) CE5 valine vălˈēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential am...

toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

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...

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...

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...

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...

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...

meditation

(Encyclopedia)meditation, religious discipline in which the mind is focused on a single point of reference. It may be a means of invoking divine grace, as in the contemplation by Christian mystics of a spiritual th...

meninges

(Encyclopedia) CE5 Meninges: Section of spine showing meningeal layers meninges mĭnĭnˈjēz [key], three membranous layers of connective tissue that envelop the brain and spinal cord (see nervous system). The ...

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...
 

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