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amphetamine

(Encyclopedia)amphetamine ămfĕtˈəmēn [key], any one of a group of drugs that are powerful central nervous system stimulants. Amphetamines have stimulating effects opposite to the effects of depressants such as...

prion

(Encyclopedia)prion prēˈŏn [key], abnormal form of a protein found in mammals, now generally believed to cause a group of diseases known as prion diseases or transmissible spongiform encephalopathies, which are ...

Guinea, country, Africa

(Encyclopedia)CE5 Guinea gĭnˈē [key], officially Republic of Guinea, republic (2015 est. pop. 12,092,000), 94,925 sq mi (245,856 sq km), W Africa. It is bounded on the north by Guinea-Bissau, Senegal, and Mal...

tobacco

(Encyclopedia)tobacco, name for any plant of the genus Nicotiana of the Solanaceae family (nightshade family) and for the product manufactured from the leaf and used in cigars and cigarettes, snuff, and pipe and ch...

leukemia

(Encyclopedia)leukemia lo͞okēˈmēə [key], cancerous disorder of the blood-forming tissues (bone marrow, lymphatics, liver, spleen) characterized by excessive production of immature or mature leukocytes (white b...

diabetes

(Encyclopedia)diabetes or diabetes mellitus məlīˈtəs [key], chronic disorder of glucose (sugar) metabolism caused by inadequate production or use of insulin, a hormone produced in specialized cells (beta cells ...

cancer, in medicine

(Encyclopedia)cancer, in medicine, common term for neoplasms, or tumors, that are malignant. Like benign tumors, malignant tumors do not respond to body mechanisms that limit cell growth. Unlike benign tumors, mali...

sexually transmitted disease

(Encyclopedia)sexually transmitted disease (STD) or venereal disease, term for infections acquired mainly through sexual contact. Five diseases were traditionally known as venereal diseases: gonorrhea, syphilis, an...

Congo, Democratic Republic of the

(Encyclopedia)CE5 Congo, Democratic Republic of the, formerly Zaïre zīˈēr, zäērˈ [key], republic ...

transplantation, medical

(Encyclopedia)transplantation, medical, surgical procedure by which a tissue or organ is removed and replaced by a corresponding part, usually from another part of the body or from another individual. A life-saving...