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Sporozoa

(Encyclopedia)Sporozoa spôrˌəzōˈə [key], phylum of unicellular heterotrophic organisms of the kingdom Protista. Unlike most other protozoans, sporozoans have no cilia or flagella. All species are parasitic an...

dandruff

(Encyclopedia)dandruff, excessive flaking of skin from the scalp, apparent as dry or greasy diffuse scaling with variable itching. It is the sign of a skin disease, such as seborrhea or a fungal infection. Treatmen...

antidiabetic drug

(Encyclopedia)antidiabetic drug, any of several drugs that control blood sugar level in the treatment of diabetes. See insulin. ...

blood transfusion

(Encyclopedia)blood transfusion, transfer of blood from one person to another, or from one animal to another of the same species. Transfusions are performed to replace a substantial loss of blood and as supportive ...

psychosomatic medicine

(Encyclopedia)psychosomatic medicine sīˌkōsōmătˈĭk [key], study and treatment of those emotional disturbances that are manifested as physical disorders. The term psychosomatic emphasizes essential unity of t...

Schaudinn, Fritz

(Encyclopedia)Schaudinn, Fritz frĭts shouˈdĭn [key], 1871–1906, German zoologist. He confirmed the work of Sir Ronald Ross and G. B. Grassi on malaria, investigated amoebic dysentery, and in his research on pr...

toxic waste

(Encyclopedia)toxic waste is waste material, often in chemical form, that can cause death or injury to living creatures. It usually is the product of industry or commerce, but comes also from residential use, agric...

Grassi, Giovanni Battista

(Encyclopedia)Grassi, Giovanni Battista jōvänˈnē bät-tēˈstä gräsˈsē [key], 1854–1925, Italian zoologist. He demonstrated (1898) that the Anopheles mosquito carries the plasmodium of malaria in its dige...

sickle cell disease

(Encyclopedia)sickle cell disease or sickle cell anemia, inherited disorder of the blood in which the oxygen-carrying hemoglobin pigment in erythrocytes (red blood cells) is abnormal. This “hemoglobin-S” crysta...

Bacon, Nathaniel

(Encyclopedia)Bacon, Nathaniel, 1647–76, leader of Bacon's Rebellion in colonial Virginia. An aristocrat (he was kin to Francis Bacon, had been educated at Cambridge and Gray's Inn, and was a member of the govern...