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yellow fever

(Encyclopedia)yellow fever, acute infectious disease endemic in tropical Africa and many areas of South and Central America. Yellow fever is caused by a virus transmitted by the bite of the female Aedes aegypti mos...

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 ...

menstruation

(Encyclopedia)menstruation, periodic flow of blood and cells from the lining of the uterus in humans and most other primates, occurring about every 28 days in women. Menstruation commences at puberty (usually betwe...

marsupial

(Encyclopedia)marsupial märso͞oˈpēəl [key], member of the order Marsupialia, or pouched mammals. With the exception of the New World opossums and an obscure S American family (Caenolestidae), marsupials are no...

Chinese music

(Encyclopedia)Chinese music, the classical music forms of China. Throughout the political and social turmoil following World War I, Western (classical and popular) and Japanese sources dominated Chinese music. At...

penicillin

(Encyclopedia)penicillin, any of a group of chemically similar substances obtained from molds of the genus Penicillium that were the first antibiotic agents to be used successfully in the treatment of bacterial inf...

prostate cancer

(Encyclopedia)prostate cancer, cancer originating in the prostate gland. Prostate cancer is one of the most common malignancies in men in the United States, second only to skin cancer, and as a cause of cancer deat...

sirenian

(Encyclopedia)sirenian sīrēˈnēən [key] or sea cow, name for a large aquatic mammal of the order Sirenia. Living sirenians are the dugong and the manatee, both found in warm, shallow waters in sheltered regions...

embryo

(Encyclopedia)CE5 Development of the human embryo embryo ĕmˈbrēō [key], name for the developing young of an animal or plant. In its widest definition, the embryo is the young from the moment of fertilizatio...

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...