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paraldehyde

(Encyclopedia)paraldehyde pârălˈdəhīdˌ [key], nervous system depressant similar to alcohol in its effects and used as a sedative. A colorless flammable liquid with a disagreeable odor, paraldehyde produces sl...

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 ...

sense

(Encyclopedia)sense, faculty by which external or internal stimuli are conveyed to the brain centers, where they are registered as sensations. Sensory reception occurs in higher animals through a process known as t...

Sherrington, Sir Charles Scott

(Encyclopedia)Sherrington, Sir Charles Scott, 1857–1952, English neurophysiologist, educated at Cambridge. He was professor of physiology at the universities of Liverpool and London and at Oxford. He contributed ...

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...

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...

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...

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...