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vitamin
(Encyclopedia)vitamin, group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either t...air pollution
(Encyclopedia)air pollution, contamination of the air by noxious gases and minute particles of solid and liquid matter (particulates) in concentrations that endanger health. The major sources of air pollution are t...medicine
(Encyclopedia)medicine, the science and art of treating and preventing disease. Modern medicine, characterized by growing specialization and a complex diagnostic and therapeutic technology, faces problems in the...Browse by Subject
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