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delusion

(Encyclopedia)delusion, false belief based upon a misinterpretation of reality. It is not, like a hallucination, a false sensory perception, or like an illusion, a distorted perception. Delusions vary in intensity,...

rickets

(Encyclopedia)rickets or rachitis rəkīˈtĭs [key], bone disease caused by a deficiency of vitamin D or calcium. Essential in regulating calcium and phosphorus absorption by the body, vitamin D can be formed in t...

statin

(Encyclopedia)statin, any of a class of drugs that reduces the amount of cholesterol in the blood by interfering with the production of cholesterol in the liver; commonly prescribed statins include atorvastatin, lo...

beriberi

(Encyclopedia)beriberi bĕrˈēbĕrˈē [key], deficiency disease occurring when the human body has insufficient amounts of thiamine (vitamin B1). The deficiency may result from improper diet (e.g., ingestion of hi...

elephantiasis

(Encyclopedia)elephantiasis ĕlˈəfăntīˈəsĭs [key], abnormal enlargement of any part of the body due to obstruction of the lymphatic channels in the area (see lymphatic system), usually affecting the arms, le...

pneumonia

(Encyclopedia)pneumonia no͝omōnˈyə [key], acute infection of one or both lungs that can be caused by a bacterium, usually Streptococcus pneumoniae (also called pneumococcus; see streptococcus), or by a virus, f...

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...

anemia

(Encyclopedia)anemia ənēˈmēə [key], condition in which the concentration of hemoglobin in the circulating blood is below normal. Such a condition is caused by a deficient number of erythrocytes (red blood cell...

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...

virus

(Encyclopedia)CE5 Structure of a tobacco mosaic virus, an RNA-containing virus virus, parasite with a noncellular structure composed mainly of nucleic acid within a protein coat. Most viruses are too small (100...