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31.
32.
Maguelone G. Forest Hervé Bétuel Philippe Couillin André Boué Michel David Daniel Floret René Francois Pierre Guibaud Henri Plauchu Raphaël Rappaport 《黑龙江环境通报》1981,1(3):197-207
Amniotic fluid (AF) levels of 17-hydroxyprogesterone (17OHP) and testosterone (T) were determined at 16–17 weeks in 17 pregnancies at risk for CAH and results compared to 75 normal controls. The fetus was predicted to be unaffected in 12 cases on the findings of normal AF levels of both 17OHP and T and the latter allowed a correct prediction of fetal sex in all instances. HLA typing confirmed normality in 12 cases revealing 5 carriers, 5 homozygous normal and 2 indeterminate. Steroid levels of the 2 groups were similar. Three fetuses were predicted to be CAH affected on unambiguously high levels of 17OHP and T (in female only). HLA typing was in agreement, and the diagnosis was confirmed in 2 abortuses and a female newborn by physical and hormonal studies. In the last 2 cases AF levels of OHP and T were normal but HLA (A/B/C) genotypes were identical to the CAH affected siblings. Normal physical and hormonal findings in the 2 aborted fetuses would exclude the possibility of an in utero virilizing form of CAH. The discrepancy could be explained on the basis that the fetuses had an allelic form of 21-hydroxylase deficiency or on the basis of recombination (not fully tested). It is concluded that a fully informative prenatal diagnosis of CAH should not rely entirely on HLA typing but on hormonal studies. 相似文献
33.
As a preliminary step to preimplantation diagnosis of sickle cell disease in unfertilized eggs or 8-cell embryos of heterozygous parents, we established quality control for detection of the mutant and normal alleles of the beta-haemoglobin gene using single buccal cells. Efficient polymerase chain reaction (PCR) amplification of a 680 base pair sequence of the beta-globin gene spanning the site of the sickle cell mutation was obtained for 79 per cent of single heterozygous cells. In 71 per cent of cases, both alleles were detected. With this current efficiency, we predict that a clinical preimplantation diagnosis at the 8-cell embryo stage could be carried out safely and reliably for a couple at risk of transmitting sickle cell disease to their children. 相似文献
34.
Diana W. Bianchi MD Gretchen K. Zickwolf Melissa C. Yih Alan F. Flint Ossie H. Geifman Marlena S. Erikson John M. Williams 《黑龙江环境通报》1993,13(4):293-300
Fetal nucleated erythrocytes (NRBC) in maternal blood are a non-invasive source of fetal DNA for prenatal genetic screening. We compared the effectiveness of three monoclonal antibodies for the separation of fetal cells from maternal blood by flow sorting. Mononuclear blood cells from 49 healthy pregnant women were incubated with antibody to CD 71, CD 36, and/or glycophorin A (GPA), employed singly or in combination with each other. These monoclonal antibodies recognize surface antigens on haematopoietic precursor cells. Successful isolation of fetal cells was defined as detection of Y chromosomal sequences in maternal blood from women carrying male fetuses, with absence of Y sequences when female fetuses were carried. Thus, gender prediction accuracy was used as a measure of fetal cell separation. Using anti-CD 71 to isolate fetal cells, gender prediction was 57 per cent correct; with anti-CD 36, it was 88 per cent correct. Anti-GPA, an erythrocyte-specific antigen, used alone or in combination with anti-CD 71 or 36, improved gender prediction to 100 per cent. We conclude that antibody to GPA improves the retrieval of fetal NRBC from maternal blood, permitting genetic analysis by the polymerase chain reaction. 相似文献
35.
We report in detail two series of chorionic villus cultivation for prenatal chromosomal diagnosis. Chorionic villi were sampled from both first- and second-trimester pregnancies. One hundred cultures were treated with trypsin–EDTA for 2 h and collagenase overnight, (method A) and 100 were treated with trypsin–EDTA for 1 h and collagenase for 2 h (method B). Using short-term enzymatic digestion, the cultivation time was reduced from 14 days to 6 days. Sufficient amounts of metaphases of good quality were present in 93 per cent of primary cultures harvested in situ, whereas enough metaphases of sufficiently good quality were in most cases present only after subcultivation of the cultures using method A. The decrease in cultivation time obtained is probably due to a higher yield of viable cells in monocellular suspension, an increased attachment efficiency, and a more rapid attachment of single cells (within 24 h). 相似文献
36.
Pregnancies with fetal trisomy 21 have been associated with low amniotic fluid alpha-fetoprotein levels (AFAFP). This observation led to the suggestion that low AFAFP levels be used as a criterion for completion of a chromosomal analysis in patients who are not otherwise at increased risk for a fetal chromosome abnormality and in whom karyotyping might not have been completed for economic reasons. In order to assess the usefulness of such criteria, we reviewed the AFAFP levels of 90 cases of fetal trisomy 21, 23 cases of trisomy 18, and 10 cases of trisomy 13. These were compared with 2400 control samples with normal chromosome constitution. AFAFP levels were generally lower in pregnancies with trisomy 21, showing a median value of 0·72 MoM. However, 40 per cent of the trisomy 21 samples had AFAFP values greater than 0·8 MoM and 20 per cent were over 1·0 MoM. These data imply that over 50 per cent of Down syndrome cases might have been missed using a cut-off level of 0·70 MoM for completion of chromosome analysis. Using a higher cut-off level will leave only a small percentage of samples unkaryotyped. The distribution of AFP levels in trisomy 13 and 18 is no different from controls; we therefore believe that fetal karyotyping should be completed in every amniotic fluid sample obtained. 相似文献
37.
基于水-岩δD-δ18O同位素交换体系理论模型的建立和计算,对金堆城超大型斑岩钼矿四个不同成矿期中成矿流体的演化和来源进行了研究,发现在成矿前期和早期,成矿流体为岩浆水与围岩在较低水/岩比值(0.1W/R>0.001)和中、高温(t=250~500℃)条件下反应后的残余流体,而主成矿期和成矿晚期的成矿流作为大气降水在相对较高水/岩比值(0.5>W/R0.1)和中、低温(t=150~310℃)条件下与围岩反应后的残留流体。大气降水在金堆城钼矿成矿过程中起了重要作用。在主成矿期水/岩比值达到最高。 相似文献
38.
Michael Legge 《黑龙江环境通报》1983,3(2):145-149
Second trimester amniotic fluid fibrinolytic system was examined in normal pregnancies and those complicated by anencephaly, spina bifida and fetal chromosome abnormalities. No significant difference was demonstrated between the fibrinolytic systems from normal pregnancies and those complicated by fetal chromosome abnormalities. In pregnancies complicated with anencephaly and spina bifida no significant difference was demonstrated for alpha-1-antitrypsin, alpha-1-antichymotrypsin and urokinase. Plasminogen was significantly lower (p < 0.02) and plasmin significantly higher (p < 0.001) than levels from normal amniotic fluid. Alpha-2-macroglobulin, fibrinogen, FDP-D and FDP-E were detected only in pregnancies complicated with anencephaly and spina bifida. 相似文献
39.
超临界二氧化碳流体萃取土壤中有机污染物的研究进展 总被引:4,自引:0,他引:4
就近年来人们利用超临界二氧化碳流体对有机污染物污染的土壤所做的研究工作以及所取得的成果进行了总结。 相似文献
40.
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