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tears

(Encyclopedia)tears, watery secretion of the lacrimal gland, which is located at the outer corner of the eye socket immediately above the eyeball. Tearing, or lacrimation, is a continuous and largely involuntary pr...

Hoffmann, Friedrich

(Encyclopedia)Hoffmann, Friedrich hôfˈmän [key], 1660–1742, German physician. He taught and practiced at Halle from 1693. He studied and wrote on such varied topics as pediatrics, mineral waters, and meteorol...

Major Planets of the Solar System (table)

(Encyclopedia)Major Planets of the Solar System ...

Chaetognatha

(Encyclopedia)CE5 Anatomy of an arrow worm, Sagitta, representative of the phylum Chaetognatha Chaetognatha kētôgnăthˈə [key], phylum of predominantly pelagic marine animals commonly known as arrowworms. A...

muscle

(Encyclopedia)muscle, the contractile tissue that effects the movement of and within the body. Muscle tissue in the higher animals is classified as striated, smooth, or cardiac, according to its structure and funct...

hypnotic drugs

(Encyclopedia)hypnotic drugs, drugs that induce sleep, sometimes called soporifics. In general, hypnotics are central nervous system depressants. Alcohol, laudanum (see opium), bromide salts, and herbs such as vale...

pilocarpine

(Encyclopedia)pilocarpine pīlōkärˈpēn [key], naturally occurring alkaloid obtained from plants of the genus Pilocarpus (family Rutaceae). By mimicking the effects of acetylcholine, pilocarpine acts as a stimul...

barbiturate

(Encyclopedia)barbiturate bärbĭchˈərātˌ [key], any one of a group of drugs that act as depressants on the central nervous system. High doses depress both nerve and muscle activity and inhibit oxygen consumpti...

trypanosomiasis

(Encyclopedia)trypanosomiasis trəpănˌəsōmīˈəsis [key], infectious disease caused by a protozoan organism, the trypanosome, which exists as a parasite in the blood of a number of vertebrate hosts. The three ...

paralysis

(Encyclopedia)paralysis or palsy pôlˈzē [key], complete loss or impairment of the ability to use voluntary muscles, usually as the result of a disorder of the nervous system. The nervous tissue that is injured m...