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461.
From 1.3.73 to 30.9.80 5580 women had an amniocentesis performed here or elsewhere; fetal chromosome analyses were carried out in this laboratory. We found 112 abnormal karyotypes (2 per cent) out of 5591 chromosome analyses. In 40 women (0.7 per cent) no cytogenetic diagnosis was obtained. Follow-up was successful in 99.5 per cent. Nine cases are reported in detail: Three cases had discrepancy between the karyotype in amniotic fluid and peripheral blood after delivery, two of these cases turned out to be 46,XX (male) while the third was prenatally determined as trisomy 21, but had a 46,XX karyotype at birth. Six cases had discrepancy between the karyotype in amniotic fluid and the phenotypic outcome at birth/abortion. One case was a prenatally undetected 45,X/46,XY mosaicism; one case was an unexplained 45,X male fetus; two cases were prenatally determined as trisomy 21, but at abortion a normal karyotype was determined and in two cases maternal cells were probably examined. The incidence of cytogeneric errors in this study was very low. 相似文献
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463.
油藏流体状态方程研究具有重要的理论和现实意义 ,它将成为流体热力学研究的一个新的生长点。论文从流体状态方程的推导方法、影响因素、主要类型等方面较系统地论述了油藏流体状态方程的研究思路和发展方向。并且从含油气系统中烃类相态的判断、油气藏类型的识别以及确定储层质量评价的物理化学模型等方面总结了其研究成果的应用进展。它将为油气藏成藏机理物理化学模型的建立和合理开发方案的制定提供新的工具 相似文献
464.
Isoelectric focusing (IEF) of amniotic fluid α-fetoprotein (AFP) in thin-layer polyacrylamide gels containing 8 M urea followed by immunoblotting reveals at least nine bands, band I lying next to the cathode. Compared with 298 amniotic fluid samples from normal pregnancies, we found that the density of band V was increased in seven cases of fetal death. In 16 amniotic fluid samples from pregnancies with open neural tube defects (ONTO), band V disappeared or was markedly decreased. In seven cases with elevated AFP and positive acetylcholines-terase (AChE) due to contamination with fetal blood, no difference in pattern was observed compared with samples from normal pregnancies. It is suggested that IEF of AFP and subsequent immunoblotting are an apparently diagnostic test for ONTD and intrauterine fetal death (IUFD). 相似文献
465.
David J. H. Brock David Bedgood Caroline Hayward Neil J. Carbarns Christine Gosden 《黑龙江环境通报》1984,4(4):261-266
Measurement of the microvillar enzymes, γ-glutamyltranspeptidase (GGTP), aminopeptidase M (APM) and alkaline phosphatase (ALP), in amniotic fluid supernatant has been proposed as a method for the early prenatal diagnosis of cystic fibrosis. The activities of these enzymes in a series of other fetal abnormalities have now been examined. GGTP activities were below the 5th percentile in 28 out of 54 cases of trisomy 21 and 9 of 14 cases of trisomy 18, while APM values were below this cut-off in 26 of 54 cases of trisomy 21 and 8 of 14 cases of trisomy 18. Abnormal ALP isoenzyme ratios were found in 6 of 54 cases of trisomy 21 and 4 of 14 cases of trisomy 18. If prenatal cytogenetic studies are routinely carried out on amniotic fluid cells, the occasional confounding effect of abnormal microvillar enzymes associated with fetal trisomies rather than with cystic fibrosis should be avoided. 相似文献
466.
A method for the measurement of the concentration of succinylacetone and 4-hydroxyphenyllactic acid in amniotic fluid was developed for the prenatal diagnosis of hereditary tyrosinemia. Succinylacetone was converted to 5-methyl-3-isoxazolepropionic acid and isolated with 4-hydroxyphenyllactic acid by liquid partition chromatography and the trimethylsilyl derivatives quantified by ammonia chemical ionization selected ion monitoring gas chromatography-mass spectrometry with 2-hydroxy-n-caproic acid as the internal standard. The concentration of 4-hydroxyphenyllactic acid in normal amniotic fluid was 1.97±0.75 (S.D.) μmol/l while succinylacetone was undetectable. A pregnancy at risk for tyrosinemia type II was monitored. The concentration of 4- hydroxyphenyllactic acid was within the normal range and a healthy child was born. 相似文献
467.
D. P. Bick E. A. Balkite M.S. A. Baumgarten J. C. Hobbins M. J. Mahoney M.D. 《黑龙江环境通报》1987,7(8):543-549
We describe a fetus with epidermolysis bullosa dystrophica and a fetus with aplasia cutis congenita who were normal by careful ultrasound examination but whose midtrimester amniotic fluids exhibited elevated concentrations of alpha-fetoprotein and presence of acetyl-cholinesterase. These cases show that serious fetal skin pathology can be a source of amniotic fluid acetylcholinesterase and elevated alpha-fetoprotein concentration and should be considered as part of the differential diagnosis of these amniotic fluid findings. 相似文献
468.
超临界流体萃取及其在环境分析中的应用 总被引:1,自引:0,他引:1
韩丛碧 《石油化工环境保护》2004,27(1):46-50
简要介绍了超临界流体萃取法的原理.仪器组成、操作条件的选择、样品预处理方法及其在土壤、水和空气等环境介质中有机污染物分析的应用。 相似文献
469.
470.