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Catherine D. Kashork V. Reid Sutton Jill S. Fonda Allen Deborah E. Schmidt Marisa L. Likhite Lorraine Potocki William E. O'Brien Lisa G. Shaffer 《黑龙江环境通报》2002,22(11):1028-1032
It has been previously reported that a low or absent maternal serum unconjugated estriol (uE3) level is associated with placental steroid sulfatase (STS) deficiency. Here we report a correlation between patients who present with a very low or absent maternal serum uE3 and a deletion of the STS gene as assessed by fluorescence in situ hybridization (FISH). We studied nine prenatal cases that presented to the clinical laboratory with an abnormal triple screen, specifically low or absent maternal serum uE3 and a 46,XY karyotype. FISH analysis showed complete deletion of a probe containing the STS gene in six cases and one case had a partial deletion (reduced but not absent signal). The remaining two cases were not deleted for the STS probe. All mothers tested whose fetus showed a deletion were shown to be STS deletion carriers using FISH. Biochemical analysis was performed on 7/9 prenatal specimens. All fetuses deleted for the STS probe were also found to be deficient for STS by biochemical analysis of cultured amniotic fluid (5/5). Of the two fetuses not deleted for the STS probe, one was deficient for STS activity, while the other had a normal result. The abnormal result of enzyme deficiency by biochemical analysis in a non-deletion case likely represents a mutation in the STS gene, not detectable by this FISH assay. Postnatal FISH confirmation of the STS deletion was performed in 1/7 cases. Clinical follow-up was available for 4/9 cases following birth. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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This paper proposes the concept of cumulative eco-intensity with which environmental or sustainability indicators are related to the added value of economic activities. The intensities are passed on recursively from supplier to supplier and thus make it possible to include upstream and downstream effects along the supply and waste disposal chain. The process is applied to whole companies and (by contrast with LCA) not to individual products. At comparatively low expenditure for the individual companies, it allows vertical comparisons along the value-adding chain and horizontal comparisons among companies or production locations. This provides a decision-making aid for a company seeking to fulfil its ecological or sustainability responsibility in the entire production and supply chains. 相似文献
217.
Dissolved uranium ((238)U(D)) was measured within the Gironde fluvial-estuarine system (France), which is well known for its heavy metal pollution and its subsequent environmental effects. Dissolved (238)U activities exhibit the highest levels and variability in the small watersheds of the Isle and Riou-Mort rivers, ascribed to low discharges and the occurrence of peculiar features (local U ore deposits; Permian layers). The major tributaries of the Gironde Estuary: Garonne, Lot and Dordogne, show rather stable (238)U(D), higher than the global mean riverine uranium activity. In the Gironde Estuary (238)U(D) behaves conservatively along the river-estuary-ocean transect. Dissolved (238)U distribution in the Gironde fluvial-estuarine system can be explained by the characteristics of considered drainage basins. There is no evidence of anthropogenic pollution. 相似文献
218.
12月7日,为期两周的联合国气候变化框架公约第15次缔约方会议(COP15)即将在丹麦首都哥本哈根拉开帷幕。这次会议在气候变化领域和全球政治进程中都是一个极为重要的“节点”,其被关注程度丝毫不亚于当下的金融危机。 相似文献
219.
Olfactory threshold and its dependence on the sexual status in the female laboratory mouse 总被引:1,自引:0,他引:1
Christel Schmidt 《Die Naturwissenschaften》1978,65(11):601-601
220.
In order to assist an integrated development of ionic liquids (ILs), a study on the sorption, distribution, and cytotoxicity of a series of 1-alkyl-3-methyl imidazolium tetrafluoroborates with C6 rat glioma cells has been performed. Cellular sorption and distribution among three cellular fractions (cytosol, nuclei, and membranes) were analysed by reversed-phase HPLC (RP-HPLC). Compounds with longer 1-alkyl substituents were sorbed with higher enrichment factors and sorption coefficients per protein than those with shorter 1-alkyl chains. The 1-octyl-3-methyl imidazolium cation (C8MIM) was enriched 17-folds whereas C6MIM and C4MIM were enriched by factors of 3.5 and 2.3, respectively. After fractionation of cells by centrifugation, about 8% of C8MIM was found in the nuclear fractions. The cytotoxicity as estimated by the tetrazolium reductase assay was increasing with the lengths of the 1-alkyl chains from C4MIM to C10MIM. Consistently, cell proliferation rates were decreasing with increasing lengths of the 1-alkyl chains. The results reveal the correlations between lipophilicity, cellular sorption, and cytotoxicity. 相似文献