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Neher, Edwin

(Encyclopedia)Neher, Edwin, 1944–, German biophysicist, Ph.D. Technical Univ. of Munich, 1970. He has been a researcher at the Max Planck Institute for Biophysical Chemistry, Göttingen, Germany, since 1972. Nehe...

vitiligo

(Encyclopedia)vitiligo, condition that causes irregular patches of skin to lose pigment and turn white. The exact cause is unknown, but it occurs when the immune system attacks and destroys melanocytes, the cells t...

Walker, Sir John Ernest

(Encyclopedia)Walker, Sir John Ernest, 1941–, English biochemist, Ph.D. Oxford, 1969. He has been a researcher at the Medical Research Council Laboratory of Molecular Biology in Cambridge since 1974. In 1997 Walk...

Skou, Jens Christian

(Encyclopedia)Skou, Jens Christian, 1918–2018, Danish chemist, M.D. Univ. of Copenhagen, 1944, Ph.D. Univ. of Aarhus, 1954. Skou was on the faculty at the Univ. of Aarhus, Denmark, from 1947 until he retired in 1...

calcium-channel blocker

(Encyclopedia)calcium-channel blocker, any of a class of drugs used in treating hypertension, angina pectoris, and certain arrhythmias. They prevent the calcium ions needed for muscle contraction from entering the ...

capillary

(Encyclopedia)capillary kăpˈəlĕrˌē [key], microscopic blood vessel, smallest unit of the circulatory system. Capillaries form a network of tiny tubes throughout the body, connecting arterioles (smallest arter...

bloodletting

(Encyclopedia)bloodletting, also called bleeding, practice of drawing blood from the body in the treatment of disease. General bloodletting consists of the abstraction of blood by incision into an artery (arterioto...

cactus

(Encyclopedia)cactus, any plant of the family Cactaceae, a large group of succulents found almost entirely in the New World. A cactus plant is conspicuous for its fleshy green stem, which performs the functions of ...

lymphoma, non-Hodgkin's

(Encyclopedia)lymphoma, non-Hodgkin's, any cancer of the lymphoid tissue (see lymphatic system) in which the Reed-Sternberg cells characteristic of Hodgkin's disease (the other category of lymphoma) are not present...

essential oils

(Encyclopedia)essential oils, volatile oils that occur in plants and in general give to the plants their characteristic odors, flavors, or other such properties. Essential oils are found in various parts of the pla...