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611.
Trisomy 9 syndrome is a rare chromosomal anomaly associated with specific patterns of multisystem dysmorphism and occasional central nervous system (CNS) malformations, the most common being the Dandy-Walker malformation. Milder anomalies are usually seen with trisomy 9 mosaicism. We report what we believe to be the first case of a baby with an isolated Dandy-Walker malformation which was diagnosed prenatally and was subsequently found to have a trisomy 9 mosaic syndrome. 相似文献
612.
Free β-HCG is a new analyte that has been suggested to be superior to total HCG when used in combination with alpha-fetoprotein (AFP) for Down syndrome risk screening in early pregnancy. We have evaluated this claim on 21 samples collected from Down syndrome pregnancies and 180 samples from unaffected pregnancies. The detection rates for the combination of AFP with free β-HCG or the combination of AFP with total HCG were identical (71 per cent) but the initial screen positive rate (equivalent to the false-positive rate) was 7·5 per cent for AFP+free β-HCG screening compared with 3·5 per cent for AFP+ total HCG screening. We conclude that the case for free β-HCG is unproven and suggest that further data be collected before free β-HCG becomes acceptable. 相似文献
613.
Dr A. L. Zaslav D. Blumenthal J. E. Fox K. A. Thomson R. Segraves M. E. Weinstein 《黑龙江环境通报》1993,13(7):569-573
Extra genetic material that is euchromatic is generally regarded to be associated with phenotypic abnormalities. However, recent studies suggest that this is not always the case. Chromosome analysis was performed on amniotic fluid cells from a 37-year-old phenotypi-cally normal patient referred for advanced maternal age. All the cells analysed showed a karyotype of 46, XY, 1p-K The 1p+ chromosome had extra genetic material of uncertain origin in chromosome band region 1p21 →31. Chromosome analysis on the father revealed a normal 46, XY male karyotype. The mother's karyotype showed the same 1p+ chromosome. C and Q banding, as well as silver staining studies, in both the mother and the fetus support the interpretation that the extra chromosomal material was euchromatic in nature. This 1p + chromosome may be characterized as a euchromatic heteromorphism. Euchromatic hetero-morphisms not associated with phenotypic abnormalities have been reported for chromosomes 9 and 16. To the best of our knowledge, this is the first report involving this type of cytogenetic anomaly on chromosome number 1 in a phenotypically normal mother and infant. 相似文献
614.
非线性理论在开采沉陷中的应用 总被引:3,自引:0,他引:3
简要介绍了近年来把非线性理论应用于矿山开采沉陷领域的一些研究成果,主要包括两大部分:(1)神经网络理论在开采沉陷中的应用;(2)离散单元法在开采沉陷中的应用 相似文献
615.
GIS支持下矿区岩溶陷落柱的综合探测技术 总被引:1,自引:0,他引:1
岩溶陷落柱是影响矿山安全生产的重要地质灾害之一,在采掘笔者提出的工程设计之前,预先探测陷落柱的空间位置和形态,可避免经济损失并保证煤矿高效安全生产。为此,论述了一种在地面综合探测陷落柱的技术,即在地理信息系统(Geographic Inform ation System , 简称GIS)支持下,对遥感图像、地质采矿资料和实地调查资料进行多因素复合分析,圈定陷落柱的可能分布区,进而实施物理勘探,确定陷落柱的具体分布参数。实践表明,这是一种行之有效的技术方法 相似文献
616.
Magiera T Kapicka A Petrovský E Strzyszcz Z Fialová H Rachwał M 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):618-627
Previous investigations revealed a strong magnetic anomaly due to soil magnetic enhancement in the industrialized cross-border area of Upper Silesia (Poland) and Northern Moravia (Czech Republic). Since industrial and urban dusts contain magnetic particles, this soil magnetic enhancement is assumed to be of anthropogenic origin, caused by a high concentration of atmospherically deposited magnetic particles, accumulated in topsoil layers. This assumption is proved by investigations of vertical profiles of magnetic susceptibility along a transect crossing the border area of the two countries. The results show that the population of magnetic minerals in the organic horizon is different from that in the mineral horizons. The vertical distribution of magnetic susceptibility and thermomagnetic analysis suggests negligible lithogenic contribution. The observed relationship between magnetic susceptibility and some heavy metals, confirmed by micromorphological observations and microchemical analysis of magnetic particles separated from the organic horizons of forest topsoil, has proved the usefulness of soil magnetometry for pollution study. 相似文献
617.
Annelieke Hijkoop Chiara C.M.M. Lap Moska Aliasi Eduard J.H. Mulder William L.M. Kramer Hens A.A. Brouwers Robertine van Baren Eva Pajkrt Anton H. van Kaam Caterina M. Bilardo Lourens R. Pistorius Gerard H.A. Visser René M.H. Wijnen Dick Tibboel Gwendolyn T.R. Manten Titia E. Cohen-Overbeek 《黑龙江环境通报》2019,39(13):1204-1212
618.
The ultrasonographer may be the first physician to suggest the presence of a fetal abnormality. A case of prenatally-detected meconium peritonitis is presented, with sonographic and radio-graphic correlation. 相似文献
619.
Dr. I. V. Tsvetkova T. V. Zolotukhina V. A. Bakharev E. L. Rosenfeld I. S. Rosovsky 《黑龙江环境通报》1983,3(3):233-236
Chorion biopsy specimens were used for prenatal assay of arylsulphatase A activity in a pregnant woman whose two children had died from metachromatic leukodystrophy (MLD). As in two subsequent pregnancies chorion arylsulphatase A was in the control range, it was concluded that both fetuses were healthy. Absence of MLD in the fetus from the first pregnancy was confirmed after assay of arylsuphatase A activity in fetal organs. The second pregnancy resulted in delivery of a healthy child. 相似文献
620.
Prenatal diagnosis of del(11)(p13p15) was made on cultured amniotic fluid cells and confirmed on fetal skin fibroblasts after termination of pregnancy. Both irides appeared behind schedule in development by 2–3 weeks in reference to the gestational age of the fetus. It is suggested that the aniridia of the aniridia-Wilms tumour association is due to developmental arrest. Confirmation of this complex is difficult at mid-gestation without critical pathological study of the eyes. 相似文献