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21.
为研究四溴二苯醚(BDE-47)对原代培养人甲状腺细胞功能的影响,分别用浓度为10-12、10-10和10-8mol·L-1的BDE-47处理原代人甲状腺滤泡上皮细胞(TEC)24h,采用化学发光酶联免疫检测法检测细胞上清液中甲状腺球蛋白(Tg)的浓度,半定量逆转录聚合酶链反应技术检测功能相关的Tg基因和双链复合蛋白8(Pax-8)基因的表达.结果表明,10-12、10-10mol·L-1暴露组Tg分泌量较对照组显著减少(p<0.05),而10-8mol·L-1BDE-47组Tg分泌量与对照组无显著性差异(p>0.05).甲状腺功能相关Tg基因和Pax-8基因的表达量随BDE-47浓度的增加而显著降低(p<0.05),呈明显的剂量-效应关系.以上结果提示,BDE-47对离体培养的原代人甲状腺细胞的功能具有抑制作用,甲状腺功能相关Tg基因和Pax-8基因的表达下调可能是其作用机制之一. 相似文献
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环境激素研究进展探讨 总被引:7,自引:0,他引:7
环境激素是一种外源性物质,能干扰生物体正常的内分泌,主要对生物体的生理过程产生很大的影响。目前已知的环境激素大概有70种左右,已经成为世界重大环境问题之一。对环境激素的概念、种类、来源、影响、作用方式以及研究现状等进行了初步的介绍。 相似文献
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环境激素类有机氯农药的用途和危害 总被引:4,自引:0,他引:4
介绍了世界自然基金会<环境中被报告具有生殖和内分泌干扰作用的化学物质清单>中16种环境激素类有机氯农药的污染状况、基本概况、用途、危害以及针对有机氯农药污染的治理措施. 相似文献
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运输应激对二花脸和皮特兰猪血浆应激和代谢相关激素水平的影响 总被引:3,自引:0,他引:3
比较二花脸和皮特兰猪在2h运输过程中血浆ACTH、皮质醇、胰岛素和T3、T4水平的动态变化模式,以分析内分泌激素变化的品种特征.选用雄性二花脸猪10头,皮特兰猪6头,体重达20kg时安装颈静脉瘘管,1wk后运输试验,运输过程中不同时间点采集血样,放射免疫分析法测定血浆激素水平.上车后两品种猪ACTH水平缓慢上升,60min后达到峰值,下车后15min恢复至基础水平,运输过程中ACTH水平及变化幅度均未表现显著的品种差异;运输前皮质醇水平二花脸显著高于皮特兰猪,上车后两品种皮质醇均迅速上升,出发后15min达到峰值,下车后15min均快速恢复至基础水平,运输过程中皮特兰皮质醇上升的幅度显著高于二花脸猪;两品种胰岛素水平上车后均呈下降趋势,二花脸胰岛素水平总体上显著高于皮特兰猪;T3水平在上车后也表现快速下降,无论是T3水平还是其变化幅度均不表现显著的品种差异;皮特兰猪上车后T4水平稍微下降而二花脸猪显著下降,皮特兰T4水平总体显著高于二花脸猪.运输应激伴随血浆ACTH和皮质醇水平升高,而胰岛素、T3和T4水平下降,皮质醇水平升高的幅度能够反映猪的应激敏感性.图1参25 相似文献
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环境激素具有类雌激素活性 ,能对生物和人体的内分泌机能造成影响 ;环境激素污染可导致各种生物的生殖功能下降和生殖器免疫力降低 ,并引起各种生理异常。本文对国内外环境重金属激素和有机激素的研究进行了综述 ,并总结了防治环境激素污染的主要技术手段 ;指出环境激素致毒生物化学机理研究、环境激素在环境介质中的迁移 转化 积累的行为研究、环境激素容量分析以及环境激素物质的进一步筛选是国际环境科学领域的重要研究方向和前沿领域。 相似文献
27.
Perchlorate as an environmental contaminant 总被引:5,自引:0,他引:5
Urbansky ET 《Environmental science and pollution research international》2002,9(3):187-192
Perchlorate anion (ClO4-) has been found in drinking water supplies throughout the southwestern United States. It is primarily associated with releases of ammonium perchlorate by defense contractors, military operations, and aerospace programs. Ammonium perchlorate is used as a solid oxidant in missile and rocket propulsion systems. Traces of perchlorate are found in Chile saltpeter, but the use of such fertilizer has not been associated with large scale contamination. Although it is a strong oxidant, perchlorate anion is very persistent in the environment due to the high activation energy associated with its reduction. At high enough concentrations, perchlorate can affect thyroid gland functions, where it is mistakenly taken up in place of iodide. A safe daily exposure has not yet been set, but is expected to be released in 2002. Perchlorate is measured in environmental samples primarily by ion chromatography. It can be removed by anion exchange or membrane filtration. It is destroyed by some biological and chemical processes. The environmental occurrence, toxicity, analytical chemistry, and remediative approaches are discussed. 相似文献
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The age at which worker honey bees begin foraging varies under different colony conditions. Previous studies have shown that
juvenile hormone (JH) mediates this behavioral plasticity, and that worker-worker interactions influence both JH titers and
age at first foraging. These results also indicated that the age at first foraging is delayed in the presence of foragers,
suggesting that colony age demography directly influences temporal division of labor. We tested this hypothesis by determining
whether behavioral or physiological development can be accelerated, delayed, or reversed by altering colony age structure.
In three out of three trials, earlier onset of foraging was induced in colonies depleted of foragers compared to colonies
depleted of an equal number of bees across all age classes. In two out of three trials, delayed onset of foraging was induced
in colonies in which foragers were confined compared to colonies with free-flying foragers. Finally, in three out of three
trials, both endocrine and exocrine changes associated with reversion from foraging to brood care were induced in colonies
composed of all old bees and devoid of brood; JH titers decreased and hypopharyngeal glands regenerated. These results demonstrate
that plasticity in age-related division of labor in honey bee colonies is at least partially controlled by social factors.
The implications of these results are discussed for the recently developed ‘‘activator-inhibitor” model for honey bee behavioral
development.
Received: 8 November 1995/Accepted after revision: 10 May 1996 相似文献