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insulin

(Encyclopedia)insulin, hormone secreted by the β cells of the islets of Langerhans, specific groups of cells in the pancreas. Insufficiency of insulin in the body results in diabetes. Insulin was one of the first ...

Cytoxan

(Encyclopedia)Cytoxan sītŏkˈsĭn [key], trade name for the drug cyclophosphamide, used to inhibit growth of tumors and rapidly proliferating cells. It is used in the treatment of leukemia, Hodgkin's disease, and...

Fischer, Edmond Henri

(Encyclopedia)Fischer, Edmond Henri, 1920–, American biochemist, b. Shanghai, China. As researchers at the Univ. of Washington in Seattle, Fischer and Edwin G. Krebs discovered a biological regulatory mechanism, ...

heparin

(Encyclopedia)heparin hĕpˈərĭn [key], anticoagulant produced by cells in many animals. A polysaccharide, heparin is found in the human body and occurs in greatest concentration in the tissues surrounding the ca...

Lynen, Feodor

(Encyclopedia)Lynen, Feodor fāōˈdôr lēˈnən [key], 1911–79, German biochemist, grad. Univ. of Munich (Ph.D. 1937). He began teaching at the Max Planck Institute for Cell Chemistry in Munich in 1947. His res...

blackhead

(Encyclopedia)blackhead, yellowish or blackish plug of material accumulated in the duct of a sebaceous gland. The material consists of keratin (horny cells of the epidermis) and modified sebum (oily secretions of t...

actinomycin

(Encyclopedia)actinomycin ăkˌtənōmīˈsən [key], any one of a group of antibiotics produced by bacteria of the genus Streptomyces. Actinomycin was the first antibiotic reported to be able to halt cancer; howev...

tissue culture

(Encyclopedia)tissue culture, the propagation of plants through the placement of small amounts of undifferentiated tissue or single cells in an artificial environment. The tissue is placed in a nutrient medium that...

Baer, Karl Ernst von

(Encyclopedia)Baer, Karl Ernst von, 1792–1876, Estonian biologist. He was a professor at Würzburg and Königsberg and from 1834 at St. Petersburg. Considered a founder of modern embryology, he discovered the not...

combine

(Encyclopedia)combine kŏmˈbīn [key], agricultural machine that performs both harvesting and threshing operations. Although it was not widely used until the 1930s, the combine was in existence as early as 1830. E...