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We have performed prenatal diagnosis for glutaryl-CoA dehydrogenase (GDH) deficiency in 16 pregnancies at risk by measuring the enzyme activity in chorionic villus samples. In most cases, GDH activity was measured both in uncultured chorionic villus samples and in cultured chorionic cells. In 4 of the 16 cases, an affected fetus was predicted, while the remaining cases were found to be normal. In three of the four affected cases, GDH activity was measured in both uncultured and cultured chorionic cells and the correct diagnosis established by both measurements. In the fourth case, only cultured cells were investigated because the chorionic villus sample was too small for the direct assay. All four pregnancies predicted to be affected were interrupted and the diagnoses confirmed on the aborted material in three of the cases. In the fourth case, no material was available for investigation. Of the 12 pregnancies predicted to be unaffected, ten cases resulted in the birth of healthy unaffected babies while two pregnancies are still in progress.  相似文献   
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Sediment samples from rivers and lakes of Berlin (Germany) were analysed for their contamination with organic compounds by means of qualitative and quantitative GC/MS analysis. The principal compounds detected were PAH, organotin derivates, several classes of chlorinated, brominated and mixed halogenated compounds and some of their related metabolites. The DDT metabolites DDD, DDE, DDCN, DDMU and DDMS were the most abundant compounds of halogenated pesticides in a wide range of samples. The main metabolite determined was p,p′-DDD, with concentrations up to 1230 μg/kg dw. The parent DDT compound was detected in only a few samples. The acute cytotoxicity of selected DDT-metabolites was determined with the permanent cell line RTG-2 from the gonads of the rainbow trout (Oncorhynchus mykiss). The results indicate a high cytotoxic potential of these metabolites. The oestrogenic potential was determined by the Dot-Blot/RNase-Protection-Assay an the order from o,p′-DDT>p,p′-DDMS>p,p′-DDMU≥p,p′-DDCN. Risk assessments based on chemical analysis of DDT, DDD and DDE alone is not able to estimate the real toxic potential of DDT and its metabolites. The development of a method for bioassay directed assessment seems to be an effective strategy to solve this problem. Especially scarce or not available data of combinatory effects, differences between different trophic levels and their availability to biota and low knowledge about the metabolism in situ as well as the enantioselective characteristics of most chiral DDT metabolites warrant future analyses.  相似文献   
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Summary. In order to elucidate the composition of the female sex pheromone of the northern (beech) winter moth, Operophtera fagata Scharf. (Lepidoptera: Geometridae), ovipositor extracts of unmated, calling females were analysed by gas chromatography with simultaneous electroantennographic and flame ionization detection (GC-EAD/FID). Male antennal responses indicated three active components, two of which had distinct matching peaks in the FID trace. Using coupled gas chromatography- mass spectrometry (GC-MS), these two compounds were identified as (9Z)-nonadecene (9Z-19:Hy), and (6Z,9Z)-nonadecadiene (6Z9Z-19:Hy), respectively. The third component, present in very small amounts only, was identified as (1,3Z,6Z,9Z)-nonadecatetraene (1,3Z6Z9Z-19:Hy), known as the sex pheromone of the common winter moth, O. brumata. Field tests revealed that traps baited with 6Z9Z-19:Hy and 1,3Z6Z9Z-19:Hy caugth large numbers of male O. fagata. Both compounds were found to be essential for attraction of O. fagata. In addition, the diene prevented captures of co-occurring O. brumata. In contrast, 9Z-19:Hy neither influenced the attractiveness of the two-component mixture towards O. fagata nor contributed to bait specificity. A binary mixture of 6Z9Z-19:Hy and 1,3Z6Z9Z-19:Hy in a ratio of 10:1, applied to pieces of rubber tubing, constituted a highly attractive and species-specific bait for O. fagata, which can be used for monitoring of the flight of this defoliator pest of deciduous forests.  相似文献   
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