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11.
We report a gas chromatographic-mass spectrometric method which allows the very long chain fatty acids content of trophoblastic tissue to be directly measured in samples collected by biopsy between 8 and 11 weeks of gestation. This method has been successfully applied to the detection of fetal Zellweger syndrome in two pregnant women who had previously delivered affected infants. In one of them, increased concentrations of C26:0 (0.254 versus 0.108±0.035 μ/mg proteins) and C24:0 (1.32 versus 0.815±0.325 μ/mg proteins) in trophoblast indicated that the fetus had Zellweger syndrome, a diagnosis confirmed by pathological findings after abortion. In the second case, the pregnancy was allowed to proceed, on the basis of normal concentrations of very long chain fatty acids in trophoblastic tissue, and its outcome was actually a healthy newborn. 相似文献
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Ossie Geifman-Holtzman Eliezer J. Holtzman Theresa J. Vadnais Vincent E. Phillips Eleanor L. Capeless Diana W. Bianchi MD 《黑龙江环境通报》1995,15(3):261-268
The objective of this study was to detect fetal HLA-DQα gene sequences in maternal blood. HLA-DQα genotypes of 70 pregnant women and their partners were determined for type A1. We specifically sought couples where the father, but not the mother, had genotype A1. In 12 women, maternal blood samples were flow-sorted. Candidate fetal cells were isolated and amplified by using PCR primers specific for a paternal HLA-DQα A1 allele. Fetal HLA-DQα A1 genotype was predicted from sorted cells; amniocytes or cheek swabs were used for confirmation. Six of twelve sorted samples had amplification products indicating the presence of the HLA-DQα A1 allele; 6/12 did not. Prediction of the fetal genotype was 100 per cent correct, as determined by subsequent amplification of amniocytes or cheek swabs. We conclude that paternally inherited uniquely fetal HLA-DQα gene sequences can be identified in maternal blood. This system permits the identification of fetal cells independent of fetal gender, and has the potential for non-invasive prenatal diagnosis of paternally inherited conditions. 相似文献
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In this paper we describe the use of five-colour fluorescence in situ hybridization for prenatal diagnosis of aneuploidy using uncultured amniotic fluid cells. The analysis is based on ratio mixing of dual-labelled probes and digital imaging for the detection and visualization of five different probes specific for the five target chromosomes, 13, 18, 21, X, and Y. A retrospective blind analysis of 30 coded uncultured amniotic fluid samples correctly detected fetal sex and five trisomy 21 cases. Multicolour fluorescence in situ hybridization used in this way allows rapid and simultaneous detection of the most frequent aneuploidies. 相似文献
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大气飘尘对大鼠肺细胞的毒性比较 总被引:1,自引:0,他引:1
采用大白鼠气管内注入飘尘后分析肺灌洗液的方法,比较了上海不同地区飘尘对大鼠肺细胞的毒性;再运用毒性指数及效应指数,综合评价了上海市不同地区大气飘尘污染的状况。研究表明:从肺灌洗液的生化成份分析及细胞分类显示,以彭浦新村、隆昌路平凉路、康定路胶州路3个点的飘尘毒性较大。综合评价结果,彭浦新村的效应指数最大,以后依次为康定路胶州路、鲁班路斜土路、青云路、隆昌路平凉路等。 相似文献
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Anna M.K. Gustafsson Mark R.StJ. Foreman Christian Ekberg 《Waste management (New York, N.Y.)》2014,34(10):1775-1782
Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS. 相似文献
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为证实固定化果胶酶抑制蓝藻生长的作用,在实验室条件下,以铜绿微囊藻(Microcystis aeruginosa)为受试藻种,用共培养法观察了固定化果胶酶对藻细胞群体的作用、用电镜观察了共培养后藻细胞的损伤状况,测定了对其生理生化特征的影响.结果表明固定化果胶酶与藻共培养液第3 d明显黄化,且黄化程度与固定化果胶酶的用量和培养时间呈正相关系;电镜照片显示固定化果胶酶对藻细胞有损伤作用,轻微损伤的藻细胞出现质壁分离,表面粗糙、凸凹不平,形状不规则,严重损伤的藻细胞表面发生深度皱缩或细胞结构完全解体;随着固定化果胶酶与铜绿微囊藻共培养时间的延长,藻细胞生长量、叶绿素a含量显著降低,表明藻细胞受到胁迫和伤害,藻细胞正常的光合作用受到严重影响.丙二醛(MDA)值显示藻细胞抗氧化防御体系被破坏,细胞内发生严重膜脂过氧化.固定化果胶酶能有效抑制铜绿微囊藻细胞的生长,铜绿微囊藻生长抑制率可高达96%. 相似文献
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以预处理剩余污泥为燃料MFC产电性能及不连续供电的可行性 总被引:1,自引:1,他引:0
为探讨微生物燃料电池(microbial fuel cell,MFC)处理经预处理后剩余污泥的可行性以及不连续供电能力,采用双室MFC,以剩余污泥热处理上清液为基质进行启动和运行,通过改变电池阴极电子受体而导致电势差变化来监测其产电的运行稳定性.结果表明,反应器以氧气作为阴极电子受体148 h后启动成功,最大输出电压0.24 V,将阴极电子受体换为铁氰化钾时,能获得0.66 V的最大输出电压和4.21 W·m~(-3)的最大功率密度.当将阴极电子受体分别替换为氧气或者开路,又转换为铁氰化钾后,电池输出功率恢复迅速,电池对有机物去除效率基本不受影响,对化学需氧量(COD)、氨氮去除效率分别达70%和80%.本研究表明,利用预处理剩余污泥进行MFC处理和产电是可行的,可获得较高的功率密度,同时MFC可以实现不连续供电. 相似文献