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Whipple, George Hoyt

(Encyclopedia)Whipple, George Hoyt, 1878–1976, American pathologist, b. Ashland, N.H., M.D. Johns Hopkins, 1905. He taught at Johns Hopkins (1909–14) and at the Univ. of California (1914–21) and was professor...

Prout, William

(Encyclopedia)Prout, William, 1785–1850, English chemist and physician. Prout's hypothesis, advanced in 1815–16, suggested that atomic weights of elements are multiples of that of hydrogen and that elements are...

congenital heart disease

(Encyclopedia)congenital heart disease, any defect in the heart present at birth. There is evidence that some congenital heart defects are inherited, but the cause of most cases is unknown. One known cause is infec...

antibody

(Encyclopedia)antibody, protein produced by the immune system (see immunity) in response to the presence in the body of antigens: foreign proteins or polysaccharides such as bacteria, bacterial toxins, viruses, or ...

salivary glands

(Encyclopedia)salivary glands sălˈəvârˌē [key], in humans, three pairs of glands that secrete the alkaline digestive fluid, saliva, into the mouth. Most animals have salivary glands that resemble those in hum...

North American Native art

(Encyclopedia)North American Native art, diverse traditional arts of Native North Americans. In recent years Native American arts have become commodities collected and marketed by nonindigenous Americans and Europe...

radiation sickness

(Encyclopedia)radiation sickness, harmful effect produced on body tissues by exposure to radioactive substances. The biological action of radiation is not fully understood, but it is believed that a disturbance in ...

Pentapolis

(Encyclopedia)Pentapolis pĕntăˈpəlĭs [key] [Gr.,=five cities], collective name anciently applied to several groups of five cities. The chief cities of Cyrenaica on the northern coast of Africa (Apollonia, Arsi...

aryl group

(Encyclopedia)aryl group ârˈĭl [key], in chemistry, group of atoms derived from benzene or from a benzene derivative by removing one hydrogen that is bonded to the benzene ring (see radical). The simplest aryl g...

cryosurgery

(Encyclopedia)cryosurgery krīˈōsrˌjərē [key], bloodless surgical technique using a supercooled probe to destroy diseased or superfluous tissue. Liquid nitrogen circulating through the instrument cools it to t...