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Purkinje, Johannes Evangelista

(Encyclopedia)Purkinje, Johannes Evangelista yōhänˈəs āˌväng-gālĭsˈtä po͝orˈkĭnyā [key], 1787–1869, Czech physiologist. While professor (1823–50) at the Univ. of Breslau he pioneered in establish...

pilocarpine

(Encyclopedia)pilocarpine pīlōkärˈpēn [key], naturally occurring alkaloid obtained from plants of the genus Pilocarpus (family Rutaceae). By mimicking the effects of acetylcholine, pilocarpine acts as a stimul...

Wald, George

(Encyclopedia)Wald, George, 1906–97, American biochemist, b. New York City, Ph.D. Columbia, 1932. He spent most of his career on the faculty at Harvard. In 1967 Wald, Haldan K. Hartline, and Ragnar Granit receive...

Granit, Ragnar

(Encyclopedia)Granit, Ragnar, 1900–1991, Swedish physiologist, M.D., Univ. of Helsinki, 1927. A professor at the Univ. of Helsinki from 1927, he joined the faculty of the Karolinska Institute, Sweden, in 1940. Gr...

glaucoma

(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...

silvereye

(Encyclopedia)silvereye: see white-eye.

spectacle bird

(Encyclopedia)spectacle bird: see white-eye.

toxoplasmosis

(Encyclopedia)toxoplasmosis, infection caused by Toxoplasma gondii, a single-celled parasitic microorganism that can infect most warm-blooded animals but reproduces only in animals of the cat family, who shed the p...

Pleiades, in astronomy

(Encyclopedia)Pleiades plēˈədēz, plīˈ– [key], in astronomy, famous open star cluster in the constellation Taurus; cataloged as M45. The cluster consists of some 500 stars, has a diameter of 35 light-years, ...

Hammurabi

(Encyclopedia)Hammurabi hämo͝oräˈbē [key], fl. 1792–1750 b.c., king of Babylonia. He founded an empire that was eventually destroyed by raids from Asia Minor. Hammurabi may have begun building the tower of B...