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scurvy

(Encyclopedia)scurvy, deficiency disorder resulting from a lack of vitamin C (ascorbic acid) in the diet. Scurvy does not occur in most animals because they can synthesize their own vitamin C, but humans, other pri...

hepatitis

(Encyclopedia)hepatitis hĕpˌətīˈtĭs [key], inflammation of the liver. There are many types of hepatitis. Causes include viruses, toxic chemicals, alcohol consumption, parasites and bacteria, and certain drugs...

tick

(Encyclopedia)tick, small, parasitic arachnid of the order Ixodida, closely related to the mites. Ticks, which are larger than the often microscopic mites, are all parasitic in at least one developmental stage; mos...

Marburg virus

(Encyclopedia)Marburg virus: see Marburg virus disease; hemorrhagic fever. ...

lumpy jaw

(Encyclopedia)lumpy jaw, infectious disease of cattle and swine caused by the bacterium Actinomyces bovis. It is characterized by an infection of the bone of the head, particularly the mandible and the maxilla, wit...

myasthenia gravis

(Encyclopedia)myasthenia gravis mīəsthēˈnēə gräˈvĭs [key], chronic disorder of the muscles characterized by weakness and a tendency to tire easily. It is caused by an autoimmune attack on the acetylcholine...

Mastigophora

(Encyclopedia)Mastigophora măsˌtĭgŏfˈərə [key], phylum of unicellular heterotrophic protozoans of the kingdom Protista. Most of the approximately 1,500 species of Mastigophora are propelled by one or more fl...

herbal

(Encyclopedia)herbal, early botanical book containing descriptions and illustrations of herbs and plants with their properties, chiefly those qualities that made them useful as medicines or condiments. Most of the ...

heartburn

(Encyclopedia)heartburn, burning sensation beneath the breastbone, also called pyrosis. Heartburn does not indicate heart malfunction but results from nervous tension or overindulgence in food or drink. The sensati...

elm

(Encyclopedia)elm, common name for the Ulmaceae, a family of trees and shrubs chiefly of the Northern Hemisphere. Elm trees (genus Ulmus) have a limited use as hardwoods for timber, especially the rock or cork elm ...