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insomnia

(Encyclopedia)insomnia, abnormal wakefulness or inability to sleep. The condition may result from illness or physical discomfort, or it may be caused by stimulants such as coffee or drugs. However, frequently some ...

inoculation

(Encyclopedia)inoculation, in medicine, introduction of a preparation into the tissues or fluids of the body for the purpose of preventing or curing certain diseases. The preparation is usually a weakened culture o...

senility

(Encyclopedia)senility sənilˈətē [key], deterioration of body and mind associated with old age. Indications of old age vary in the time of their appearance. Stooped posture, wrinkled skin, decrease in muscle st...

plant breeding

(Encyclopedia)plant breeding, science of altering the genetic pattern of plants in order to increase their value. Increased crop yield is the primary aim of most plant-breeding programs; advantages of the hybrids a...

toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

Raglan, Fitzroy James Henry Somerset, 1st Baron

(Encyclopedia)Raglan, Fitzroy James Henry Somerset, 1st Baron, 1788–1855, British general. He entered the army in 1804 and was made (1814) a lieutenant colonel for his services on the duke of Wellington's staff i...

Netter, Frank Henry

(Encyclopedia)Netter, Frank Henry, 1906–1991, American physician and medical illustrator, b. Brooklyn, N.Y. He attended City College as well as the National Academy of Design and Art Students League and became a ...

valine

(Encyclopedia)CE5 valine vălˈēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential am...

Cayenne

(Encyclopedia)Cayenne kīĕnˈ, kāĕnˈ [key], city and district (2021 est. pop. 61,550), capital of French Guiana, on Cayenne isl...

Venter, Craig

(Encyclopedia)Venter, Craig (John Craig Venter), 1946–, American biotechnologist and pioneering genome mapper, b. Salt Lake City, grad. Univ. of California, San Diego (B.A. 1972, Ph.D. 1975). Joining the National...