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colon cancer

(Encyclopedia)colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. Epidemiological evidence has shown that ...

impotence

(Encyclopedia)impotence imˈpətəns [key], inhibited sexual excitement in a man during sexual activity that, despite an unaffected desire for sex, results in inability to attain or maintain a penile erection. Know...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

bacteriophage

(Encyclopedia)bacteriophage băktērˈēəfājˌ [key], virus that infects bacteria and sometimes destroys them by lysis, or dissolution of the cell. Bacteriophages, or phages, have a head composed of protein, an i...

Curie

(Encyclopedia)Curie kürēˈ [key], family of French scientists. Pierre Curie, 1859–1906, scientist, and his wife, Marie Sklodowska Curie, 1867–1934, chemist and physicist, b. Warsaw, are known for their work o...

gene

(Encyclopedia)gene, the structural unit of inheritance in living organisms. A gene is, in essence, a segment of DNA that has a particular purpose, i.e., that codes for (contains the chemical information necessary f...

amphetamine

(Encyclopedia)amphetamine ămfĕtˈəmēn [key], any one of a group of drugs that are powerful central nervous system stimulants. Amphetamines have stimulating effects opposite to the effects of depressants such as...

methadone

(Encyclopedia)methadone mĕthˈədōnˌ, –dŏnˌ [key], synthetic narcotic similar in effect to morphine. Synthesized in Germany, it came into clinical use after World War II. It is sometimes used as an analgesic...

penicillin

(Encyclopedia)penicillin, any of a group of chemically similar substances obtained from molds of the genus Penicillium that were the first antibiotic agents to be used successfully in the treatment of bacterial inf...

psychoanalysis

(Encyclopedia)psychoanalysis, name given by Sigmund Freud to a system of interpretation and therapeutic treatment of psychological disorders. Psychoanalysis began after Freud studied (1885–86) with the French neu...