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blood test

(Encyclopedia)blood test, examination of blood routinely or as an aid in diagnosing a suspected disease. Tests may be performed on whole blood or on the plasma portion only. Blood typing identifies the proteins at ...

genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

water supply

(Encyclopedia)water supply, process or activity by which water is provided for some use, e.g., to a home, factory, or business. The term may also refer to the supply of water provided in this way. In the United Sta...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

Lyme disease

(Encyclopedia)Lyme disease or Lyme borreliosis, a nonfatal bacterial infection that causes symptoms ranging from fever and headache to a painful swelling of the joints. The first American case of Lyme's characteris...

cholera

(Encyclopedia)cholera kŏlˈərə [key] or Asiatic cholera, acute infectious disease caused by strains of the bacterium Vibrio cholerae that have been infected by bacteriophages. The bacteria, which are found in fe...

alfalfa

(Encyclopedia)alfalfa lo͞osûnˈ [key], perennial leguminous plant (Medicago sativa) of the family Leguminosae (pulse family), the most important pasture and hay plant in North America, also grown extensively in A...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

endocarditis

(Encyclopedia)endocarditis ĕnˌdōkärdīˈtĭs [key], bacterial or fungal infection of the endocardium (inner lining of the heart) that can be either acute or subacute. In the acute form the symptoms (fever, mala...

tryptophan

(Encyclopedia)CE5 tryptophan trĭpˈtəfăn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essent...