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marijuana

(Encyclopedia)marijuana or marihuana, drug obtained from the flowering tops, stems, and leaves of the hemp plant, Cannabis sativa (see hemp) or C. indica; the latter species can withstand colder climates. It is one...

blood

(Encyclopedia)blood, fluid pumped by the heart that circulates throughout the body via the arteries, veins, and capillaries (see circulatory system; heart). An adult male of average size normally has about 6 quarts...

antibiotic

(Encyclopedia)antibiotic, any of a variety of substances, usually obtained from microorganisms, that inhibit the growth of or destroy certain other microorganisms. Although for centuries preparations derived from ...

drugs

(Encyclopedia)drugs, substances used in medicine either externally or internally for curing, alleviating, or preventing a disease or deficiency. At the turn of the century only a few medically effective substances ...

AIDS, in medicine

(Encyclopedia)AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, and neuro...

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...