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Biomarker responses in Macoma nasuta (Bivalvia) exposed to sediments from northern San Francisco Bay
Our study investigates biomarker responses and survival of Macoma nasuta exposed to sediments collected from six locations in northern San Francisco Bay. Biomarkers analyzed were stress proteins (hsp70) in gill, mantle and digestive gland, lysosomal membrane damage and histopathologic lesions. Sediments and clam tissues were analyzed for a comprehensive suite of heavy metals and trace organic pollutants. Sediment grain size and organic carbon content were determined. Clams accumulated metals, polyaromatic hydrocarbons (PAHs) and organochlorine pesticides (aldrin and p,p(')-DDT and its metabolites p,p(')-DDD and p,p(')-DDE). Pearson and Spearman correlation analysis revealed that mortality, hsp70 in gill and histopathologic lesion scores in gonads, and lysosomal membrane damage were significantly correlated with tissue concentrations of DDT and/or its metabolites. Tissue concentrations of metals, in particular nickel, chromium, and copper, were associated with macrophage aggregates in digestive gland and germ cell necrosis. Cadmium was linked to mortality and lysosomal membrane damage. 相似文献
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再沉积钙质超微化石揭示了末次间冰期洛朗蒂德融水流向墨西哥湾的历史Ｔ．Ｍ．Ｍａｒｃｈｉｔｔｏ等Ｂｒｏｅｃｋｅｒ等（１９８９）曾根据奥卡盆地１６ｈａｇ１７ｈａ（１４Ｃ年代）浮游有孔虫δ１８Ｏ记录来解释流入墨西哥湾的融水流的特征．他们发现１２．７－１１．３... 相似文献
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１引言在适当条件下 ,海底沉积物中的气水合物稳定带的基底以似海底反射（ＢＳＲ）为标志。为此ＢＳＲｓ通常被当成海底气水合物的指示物。如地震反射波法发现的ＢＳＲｓ附近波速的分布已经利用多偏移距反射数据的全波形反演法在世界若干地方做过研究。来自各地的结果表明具有高振幅特征的ＢＳＲ下伏薄层游离气层（Ｓｉｎｇｈ等 ,１９９３）。这已经被钻探所证实（Ｍａｃｋａｙ等 ,１９９４ ;Ｈｏｌｂｒｏｏｋ等 ,１９９６）。但是 ,ＢＳＲｓ的反射波并非总是高振幅的 ,通常表现出较大的横向变化。其原因还不太清楚。利用波形反演法研究ＢＳ… 相似文献