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tranquilizer

(Encyclopedia)tranquilizer, drug whose action calms the central nervous system, decreasing emotional agitation without impairing alertness. Tranquilizing drugs differ from hypnotic drugs such as barbiturates in tha...

thrombosis

(Encyclopedia)thrombosis thrŏmbōˈsĭs [key], obstruction of an artery or vein by a blood clot (thrombus). Arterial thrombosis is generally more serious because the supply of oxygen and nutrition to an area of th...

Ramón y Cajal, Santiago

(Encyclopedia)Ramón y Cajal, Santiago säntyäˈgō rämōnˈ ē kähälˈ [key], 1852–1934, Spanish histologist, widely considered the father of neuroscience. He was a university professor at Valencia (1881–8...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

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...

aggression

(Encyclopedia)aggression, a form of behavior characterized by physical or verbal attack. It may appear either appropriate and self-protective, even constructive, as in healthy self-assertiveness, or inappropriate a...

eating disorders

(Encyclopedia)eating disorders, in psychology, disorders in eating patterns that comprise four categories: anorexia nervosa, bulimia, rumination disorder, and pica. Anorexia nervosa is characterized by self-starvat...

herbal

(Encyclopedia)herbal, early botanical book containing descriptions and illustrations of herbs and plants with their properties, chiefly those qualities that made them useful as medicines or condiments. Most of the ...

narcolepsy

(Encyclopedia)narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and recurring unwanted episodes of sleep (“sleep attacks”). People with narcolepsy may abruptly fall asleep at almost any...

oxytocin

(Encyclopedia)oxytocin ŏksĭtōˈsĭn [key], hormone released from the posterior lobe of the pituitary gland that facilitates uterine contractions and the milk-ejection reflex. The structure of oxytocin, a cyclic ...