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Effects of methyl-, phenyl-, ethylmercury and mercurychlorid on immune cells of harbor seals (Phoca vitulina) 总被引:1,自引:0,他引:1
Antje Kakuschke Elizabeth Valentine-Thon Sonja Fonfar Katharina Kramer Andreas Prange 《环境科学学报(英文版)》2009,21(12):1716-1721
Mercury (Hg) is present in the marine environment as a natural metal often enhanced through human activities. Depending on its
chemical form, Hg can cause a wide range of immunotoxic e ects. In this study, the influence of methyl-, ethyl- and phenylmercury as
well as mercurychloride on immune functions was evaluated. Two parameters of cellular immunity, proliferation and mRNA cytokine
expression of interleukin-2, -4, and transforming growth factor , were investigated in harbor seal lymphocytes after in vitro exposure
to Hg compounds. While all Hg compounds had a suppressive e ect on proliferation, di erences between juvenile and adult seals
were found. Lymphocytes from juveniles showed a higher susceptibility to the toxic e ect compared to lymphocytes from adults.
Furthermore, the degree of inhibition of proliferation varied among the four Hg compounds. The organic compounds seem to be
more immunotoxic than the inorganic compound. Finally, for the cytokine expression of methylmercury-incubated lymphocytes, timedependent
changes were observed, but no dose-dependency was found. Marine mammals of the North Sea are burdened with Hg, and
lymphocytes of harbor seals may be functionally impaired by this metal. The present in vitro study provides baseline information for
future studies on the immunotoxic e ects of Hg on cellular immunity of harbor seals. 相似文献
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<正>海豚的捕食技巧不但令人叫绝,有的还很有科技含量,它的智慧超群,确实是哺乳动物中除人类之外的佼佼者。讲究"排兵布阵"美国研究人员发现,生活在佛罗里达海岸边的海豚非常讲究"排兵布阵",能 相似文献
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美国濒危物种立法例外条款简介 总被引:1,自引:0,他引:1
据国际自然保护同盟(IUCN)统计,全世界380种野生植物种群已经绝灭,另外还有371种介于灭绝和濒危之间状况。有6522种植物被定为濒危物种,1/4哺乳动物和11%鸟类面临灭绝的危险。这些数据记录的只是已知的绝灭种类。肯定还有许多已经绝灭但我们却还一无所知的物种。上世纪半叶世界各国根据本国情况分别通过立法保护濒危物种,取得了可观的成就,现就美国濒危物种保护若干规定作一简要介绍,以期参照借鉴。 相似文献