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heartburn

(Encyclopedia)heartburn, burning sensation beneath the breastbone, also called pyrosis. Heartburn does not indicate heart malfunction but results from nervous tension or overindulgence in food or drink. The sensati...

synapse

(Encyclopedia)synapse sĭnˈăps [key], junction between various signal-transmitter cells, either between two neurons or between a neuron and a muscle or gland. A nerve impulse reaches the synapse through the axon,...

physiology

(Encyclopedia)physiology fĭzēŏlˈəjē [key], study of the normal functioning of animals and plants during life and of the activities by which life is maintained and transmitted. It is based fundamentally on the...

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...

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 ...

tetanus

(Encyclopedia)tetanus tĕtˈnəs, –ənəs [key] or lockjaw, acute infectious disease of the central nervous system caused by the toxins of Clostridium tetani. The organism has a widespread distribution and is com...

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...

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 ...

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...

shock

(Encyclopedia)shock, any condition in which the circulatory system is unable to provide adequate circulation to the body tissues, also called circulatory failure or circulatory collapse. Shock results in the slowin...