thymus
thymus An organ, present only in vertebrates, that is concerned with development of
lymphoid tissue, particularly the white blood cells involved in cell-mediated
immune responses (see
T cell). In mammals it is a bilobed organ in the region of the lower neck, above and in front of the heart. The thymus undergoes progressive shrinkage (involution) throughout life, starting after the first 12 months. Haemopoietic stem cells from the bone marrow migrate to the thymus, attracted by chemotactic factors, and begin to divide and differentiate to form the many subpopulations of T cells. As their progeny cells migrate through the thymus from its cortex to medulla, they interact with thymic ‘nurse cells’ and with each other and are influenced by various extracellular proteins and thymic peptide hormones (e.g. thymosin and thymopoietin). All these factors help to promote the differential expression of surface antigens and development of distinctive immunological competences.
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Council calls for timely cyclamate reapproval. (Calorie Control Council)
PR Newswire; 5/16/1989; 700+ words
; COUNCIL CALLS FOR TIMELY CYCLAMATE REAPPROVAL ATLANTA, May 16 /PRNewswire...it looks forward to reapproval of cyclamate as soon as possible in light of reports...that FDA had "made a mistake" with cyclamate. "We are encouraged by Dr. Scheuplein...
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U.S. Expected To Lift Ban On Cyclamate; Sweetener Harmless, Most Experts Say
Newspaper article from: The Washington Post; 5/16/1989; ; 700+ words
; ...who banned the artificial sweetener cyclamate 20 years ago in the midst of one of the...from bladder cancer to birth defects, cyclamate is now widely thought to be harmless. "I have no reluctance in saying that with cyclamate we made a mistake," said Robert Scheuplein...
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Cyclamate: a reappraisal.
Magazine article from: Science News; 6/15/1985; 677 words
; ...existing studies on cyclamates and cancer. The committee...cultures at least, cyclamate can act with carcinogenic...interpreted to predict cyclamate's possible health effects on humans. Cyclamates were banned after researchers...1960s concluded that cyclamate/saccharin mixtures...
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U.S. Claims Court Judge determines that Food and Drug Adminstration was erroneous in linking cyclamate and cancer in laboratory animals.
PR Newswire; 12/26/1984; 700+ words
; ...misinformation surrounding cyclamate's removal from the...growing consensus that cyclamate should be available to...vegetables containing cyclamates, went out of business...due to lost sales when cyclamate was taken off the U...
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FDA Confirms Cyclamate Ban May End
Newspaper article from: The Washington Post; 5/17/1989; ; 590 words
; ...old ban on the artificial sweetener cyclamate but said that a number of scientific...scientific studies have indicated that cyclamate can damage the chromosomes of cells grown...According to the agency, the allegation that cyclamate is a carcinogen has been resolved, but...
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Cyclamate revisited. (new research)
Magazine article from: FDA Consumer; 9/1/1985; 623 words
; ...the original manufacturer of cyclamate, petitioned FDA for approval...taken together, does not show cyclamate to be a carcinogen. Asked...safety and remarketing of cyclamate must await completion and...of next year. (More about cyclamates and other non-sugar sweeteners...
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Sweet dreams. (artificial sweetener cyclamate)
Magazine article from: Reason; 10/1/1993; ; 692 words
; ...Administration banned the artificial sweetener cyclamate. For more than a decade, until the...aftertaste of saccharin. The FDA's cyclamate decision was based on a 1969 study in...results could not be reproduced. Yet cyclamate remains illegal. A recent report from...
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The Jury's Still Out on Cyclamate
Newspaper article from: The Washington Post; 6/10/1989; 545 words
; ...May 16} that "the jury on cyclamate is in" reflects shallow reporting...only a moderate dosage of cyclamate and just 10 monkeys per group...is too small to prove that cyclamates do or do not cause cancer...who reaffirmed a ban on cyclamate in 1980 (Commissioner Alexander...
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 "The Mirror (London, England)")
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BANNED SWEETENER IS BACK ON SHELVES; INVESTIGATES FOOD SAFETY; 1969: Cyclamate is put on danger list; 1997: OK here but still outlawed in US.(News)
Newspaper article from: The Mirror (London, England); 1/16/1997; ; 621 words
; ...soft drinks containing cyclamates could be at risk...drink is sweetened with cyclamate it would contain 145mg...excessive levels of cyclamates could reduce testosterone...know nothing about cyclamates and what they might...up tests proved that cyclamate did not pose a health...
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Bangladesh bans use of sodium cyclamate in food, pharmaceutical items
News Wire article from: Xinhua News Agency; 3/7/2006; 409 words
; Bangladesh bans use of sodium cyclamate in food, pharmaceutical items DHAKA...government has banned the use of sodium cyclamate, an artificial sweetening agent...According to the daily, sodium cyclamate, at least 30 times sweeter than...
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Cyclamate
Encyclopedia entry from: The Gale Encyclopedia of Science
Cyclamate Regulatory controversy Resources Cyclamate (chemical formula C6 H13 NO3 S) is an artificially-made...While still available in some countries, the sale of cyclamate and its use as a sweetener in processed foods has been banned...
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cyclamate
Book article from: The Columbia Encyclopedia, Sixth Edition
cyclamate , any member of a group of salts of cyclamic...reports that ingestion of large quantities of cyclamates appeared to cause cancer in some animals. There is no evidence that cyclamates are associated with cancer in humans.
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cyclamates
Book article from: A Dictionary of Biology
cyclamates Salts of the acid C 6 H 11 .NH.SO 3 H, where C 6 H 11 – is a cyclohexyl group. Sodium and calcium cyclamates were formerly used as sweetening agents in soft drinks, etc., until their use was banned when they were suspected of causing cancer.
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calcium cyclamate
Book article from: A Dictionary of Biology
calcium cyclamate An organic calcium salt, (C 6 H 11 NHSO 3 )Ca.2H 2 O, that has a very sweet taste and was formerly used as a sweetening agent. Its use was banned in the UK in 1969 as it was suspected of causing cancer.
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Sugar Substitutes
Book article from: American Decades
...leave a bitter after-taste. Cyclamates, the other substitute, are...outweigh the negative, however, Cyclamates can kill. Cyclamate Controversy Dr. Jacqueline...experimented with chicken embryos and cyclamates in 1966. She found that the...
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