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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 ...

Lord's Supper

(Encyclopedia)Lord's Supper, Protestant rite commemorating the Last Supper. In the Reformation the leaders generally rejected the traditional belief in the sacrament as a sacrifice and as an invisible miracle of th...

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...

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 ...

depth charge

(Encyclopedia)depth charge, explosive device used against submarines and other underwater targets, either rolled into the water from rails on the stern of a ship or propelled from depth charge throwers. The charge ...

detonator

(Encyclopedia)detonator dĕˈtənāˌtər [key], type of explosive that reacts with great rapidity and is used to set off other, more inert explosives. Fulminate of mercury mixed with potassium chlorate is a common...

Saha, Meghnad

(Encyclopedia)Saha, Meghnad māgnädˈ säˈhä [key], 1893–1956, Indian physicist. He was a professor at Allahabad Univ. from 1923 to 1938 and a professor and physics department head at Calcutta Univ. from 1938....