对我国古生物化石自动化鉴定和分类研究的商讨     

雒昆利 《长春地质学院学报》1992,22(3):315-316,232

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现代腕足动物壳体的δ^18O和δ^13C值     

Scott  JC 蓝先洪 《海洋地质前沿》1996,(7):10-13

现代腕足动物壳体的δ~（１８）Ｏ和δ~（１３）Ｃ值Ｊ。Ｃ。Ｓｃｏｔｔ等在过去的３４年里，许多科技工作者利用古代腕足动物壳体的δ１８值作为古海水δ１８Ｏ值或温度的长期变化的指示物。最近，腕足动物壳体的δ１８Ｏ值被用来计算古海水的温度、密度和盐度，以了解古...  相似文献   

烃垂直运移：一个重要的勘探参数     

Prat.  JC 宁志兵 《海洋地质译丛》1992,(2):10-18

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Glucuronidation in the polar bear (Ursus maritimus)     

Sacco JC  James MO 《Marine environmental research》2004,58(2-5):475-479

Polar bears bioaccumulate lipophilic pollutants, including polychlorinated biphenyls (PCBs), into their bodies from their exclusive diet of marine organisms. Hydroxylated PCB metabolites (OH-PCBs) have been found in plasma, presumably due to CYP-dependent biotransformation of PCBs in liver. Little is known about the phase 2 metabolism of hydroxylated xenobiotics in polar bears. The objective of this study was to examine UDP-glucuronosyltransferase (UGT) activity with OH-PCBs and a hydroxylated polycyclic aromatic hydrocarbon, 3-hydroxy-benzo(a)pyrene (3-OH-BaP), in polar bear liver. Samples of frozen polar bear liver were used to prepare microsomes. UGT activity with 3-OH-BaP in Brij-treated microsomes, measured by a fluorescence assay, was readily measurable with protein concentrations in assay tubes of up to 10 g/ml, but dropped off very sharply at higher protein concentrations. The apparent Km for 3-OH-BaP was 1.71 +/- 0.04 microM, and Vmax 1.26 +/- 0.16 nmol/min/mg protein (mean +/- SD, n=3). UGT activities with a model tetrachloro-OH-PCB (4'-OH-CB72) and a model hexachloro-OH-PCB (4'-OH-CB159) were assayed with [14-C]-UDPGA and separation of the [14-C]-glucuronide by ion-pair extraction and thin-layer chromatography. [14-C]-glucuronide conjugates were readily formed by polar bear liver microsomes in the absence of added substrate, apparently from contaminants present in liver. This phenomenon was not observed using hepatic microsomes from laboratory-held catfish. Glucuronidation efficiency was much higher with 4'-OH-CB72 (Km 7.3 microM; Vmax 1.55 nmol/min/mg) than 4'-OH-CB159 (Km 16.1 microM; Vmax 0.46 nmol/min/mg). The identities of the aglycones present in polar bear liver are not known, but could include OH-PCBs or hydroxylated metabolites of other persistent organic pollutants. This study demonstrates that UGT with high activity for 3-OH-BaP and other substrates is present in polar bear liver.  相似文献   

Zinc concentration effect at the organismal,cellular and subcellular levels in the eastern oyster     

Meiller JC  Bradley BP 《Marine environmental research》2002,54(3-5):401-404

The purpose of this research was to demonstrate a concentration effect of zinc exposure at organismal, cellular and sub-cellular levels in the eastern oyster and to find associated protein expression signatures (PES) for each concentration of zinc. Oysters were exposed to six concentrations of zinc for 48 h in a controlled environment. At the organismal level, fecal material was observed as a measure of physiological health during metal exposures. At the cellular level, lysosomal destabilization was measured using hemolymph. This cellular response was significant only at the highest concentration, when the fecal index was lowest. Protein responses were monitored in the oyster following exposure to zinc. Gill tissue was excised and homogenized, and then analyzed using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and digital image analysis. Protein expression signatures were found to be specific to each concentration. The protein responses were linked to the other biological parameters measured, each of which followed a concentration gradient of zinc.  相似文献   

高纬海区沉积物的高分辨铀系测年：^230Th—δo^18地层学     

Scho.  JC 杨明慧 《海洋地质译丛》1995,(5):65-70

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东太平洋海山的热液氧化物和绿脱石矿床     

Alt.  JC 陆文 《海洋地质译丛》1989,(2):57-63,79

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红海湾水域溶解氧、pH值、盐度和营养盐分布特征及相互关系研究   总被引：10，自引：0，他引：10  

王小平  贾晓平  林钦  李纯厚  甘居利  蔡文贵  王增焕  吕晓瑜 《海洋通报》1999,18(5):35-40

通过１９９８年６月对广东省红海湾海水养殖水域环境因子的调查,阐述了海水中溶解氧、盐度、ｐＨ值和营养盐的分布特征及其变化规律,并讨论了它们之间的相互关系,结果表明,溶解氧及海水ｐＨ值随温度由北（除１５￣１７号站）向南（除６号站）增高而增高。同时证实了光合作用是导致溶解氧含量和ｐＨ值增高的主要原因。而营养盐与盐度呈密度的负相关,浮游植物总量随营养盐由北向南降低而明显增高。  相似文献   

胶州湾东北部海水中锌的存在形态及其分布     

王恕昌史致丽  孙秉一王永辰于圣睿  戴国升李良忠张凤兰  柯东胜张云利 《山东海洋学院学报》1980,10(1):64-78

研究微量元素在海水中的存在形态是海洋化学上比较重要的课题之一，对了解微量元素在海洋中的循环具有重要的意义。关于锌在海洋中的存在形态曾有过详细的评论．  相似文献   

大油气田的位置：据安第斯前陆的一些实例     

Prat.  JC 方孝悌 《海洋地质译丛》1995,(1):70-76

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