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981.
Frans J. Los MD PhD Diane Van Opstal Martin P. Schol Johannes L. J. Gaillard Helen Brandenburg Ans M. W. Van Den Ouweland Peter A. In 'T Veld 《黑龙江环境通报》1995,15(12):1155-1159
A prenatally detected case of a rare mosaic tetrasomy 12p/trisomy 12p is reported, presenting as the well-known accessory isochromosome 12p and a supernumerary single 12p marker in 17/24 and 6/24 clones of cultured amniotic fluid cells, respectively. The chromosomal nature of both marker chromosomes was investigated in cultured amniotic fluid cells by fluorescent in situ hybridization with various probes: the 12-centromeric probes pa12H8 and D12Z3, a whole chromosome 12 paint, and the chromosome 12p-specific paint M28. DNA analysis revealed a maternal origin of the extra 12p material. After counselling, the parents requested termination of pregnancy. Inspection and autopsy of the fetus revealed many of the dysmorphisms and internal structural abnormalities of the Pallister–Killian syndrome. 相似文献
982.
Upper limb reduction was diagnosed by ultrasound scan at 17 weeks after chorion villus sampling at 9 weeks' gestation. Pregnancy was terminated and necropsy confirmed limb reduction in an otherwise normal fetus. The relationship of limb reduction to amniotic band syndrome is discussed. 相似文献
983.
984.
985.
Perfluorooctane sulfonate(PFOS) is a persistent organic pollutant(POP) and emergent contaminant that are widespread in the environment. Understanding the mechanisms controlling the distribution of PFOS and its isomers between hydrargillite and the water phase is important in order to study their redistribution and mobility in the environment. This study investigated the effects of pH, humic acid, fulvic acid and Na2SO4 on sorption of PFOS isomers to hydrargillite. A mixture... 相似文献
986.
987.
IntroductionTheprocessofmunicipalsolidwaste(MSW)isoneofthemostseriousissuesintermsofenvironmentalprotection.ProcessingofMSWwithoutfurtherdisastrouscontaminationcanbeachievedonlyinmodernizedmeasures,suchasincineratingandenergygeneratingconcurrently(Shen… 相似文献
988.
城市污泥堆肥中水溶性有机物的理化特性变化 总被引:12,自引:1,他引:12
通过透析和XAD-8树脂等方法研究了城市污泥堆肥过程中水溶性有机物(DOM)的理化特性变化.结果表明,随着堆肥的进行,堆肥DOM的浓度和pH值分别降低了58.4%和9.5%;DOM中小分子组分和亲水性组分分别减少了13.1%和9.2%,而大分子组分与疏水性组分有所增加,疏水性组分/亲水性组分由0.89增至1.29;DOM中C、H、N、S含量和C/H、C/N、C/S、C/(N+S)均呈降低趋势.这些变化趋势与堆肥过程中有机物的变化规律一致,因此,堆肥DOM的理化特性能用以表征堆肥的腐熟度. 相似文献
989.
990.
A. Schiariti A. D. Berasategui D. A. Giberto R. A. Guerrero E. M. Acha H. W. Mianzan 《Marine Biology》2006,149(3):483-489
The Río de la Plata is one of the main estuarine systems of South America. It is characterized by a salt wedge regime, a well-developed bottom salinity front, and a maximum turbidity zone associated with it. We described, for the first time, the spatial distributional patterns of Neomysis americana, the most abundant mysid and the main food item for juvenile fishes in this estuary. We analyzed the link between mysid distribution and abundance and the bottom salinity gradient. A total of 242 plankton samples were taken from the Río de la Plata estuary in spring and fall between 1991 and 2001. Bottom salinity gradient was quantified from grids created on the basis of 348 oceanographic stations. The N. americana population was characterized by high abundances (up to 2500 ind. m−3), with juveniles, males, gravid and non-gravid females present in both spring and fall of different years. N. americana distribution followed the position of the bottom salinity front in different years and seasons. Pearson’s correlation analysis between mysid abundance and bottom salinity gradient confirmed the association of mysids with the bottom salinity front (maximum salinity gradient). No correlation was detected between mysid abundance and salinity per se or temperature (neither in spring nor in fall). We speculate that mysids concentrated at the front could take advantage of the high concentration of detrital material for feeding. The results of our work highlight the importance of the magnitude of salinity gradient for the ecological processes of a salt-wedge estuary like the Río de la Plata. The analysis of the spatial distribution of gradient values presented in this work also constitutes a useful tool to locate key ecological areas such as fronts. 相似文献