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electric shock

(Encyclopedia)electric shock, effect of the passage of a current of electricity through the body. Fatality may result from shocks of from 1 to 2 amperes and 500 to 1,000 volts. However, the effect of electric shock...

vomiting

(Encyclopedia)vomiting, ejection of food and other matter from the stomach through the mouth, often preceded by nausea. The process is initiated by stimulation of the vomiting center of the brain by nerve impulses ...

Nemertinea

(Encyclopedia)CE5 A. Ribbon worm, representative of the phylum Nemertinea B. Internal anatomy of a ribbon worm Nemertinea nĕmərtĭnˈēə [key], phylum of elongated, often flattened, marine Worms, sometimes c...

Charcot, Jean Martin

(Encyclopedia)Charcot, Jean Martin zhäN märtăNˈ shärkōˈ [key], 1825–93, French neurologist. At the Salpêtrière in Paris he developed the greatest clinic of his time for diseases of the nervous system. He...

Huntington's disease

(Encyclopedia)Huntington's disease, hereditary, acute disturbance of the central nervous system usually beginning in middle age and characterized by involuntary muscular movements and progressive intellectual deter...

intoxication

(Encyclopedia)intoxication, condition of body tissue affected by a poisonous substance. Poisonous materials, or toxins, are to be found in heavy metals such as lead and mercury, in drugs, in chemicals such as alcoh...

spinal puncture

(Encyclopedia)spinal puncture, surgical penetration of the spinal canal by a hollow needle introduced between two of the lumbar vertebrae. The arrangement permits injection of antibiotics or anesthetics (see anesth...

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...

acetylcholine

(Encyclopedia)acetylcholine əsētˌəlkōˈlēn [key], a small organic molecule liberated at nerve endings as a neurotransmitter. It is particularly important in the stimulation of muscle tissue. The transmission ...

brain stem

(Encyclopedia)brain stem, lower part of the brain, adjoining and structurally continuous with the spinal cord. The upper segment of the human brain stem, the pons, contains nerve fibers that connect the two halves ...