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891.
Adaptations of the techniques of modern molecular biology to prenatal diagnosis has opened new avenues for the detection of genetic diseases. We have taken advantage of the rapid adhesion of colony forming cells in cultured amniotic fluid samples to develop an improved method for molecular diagnosis. By employing the cell adherence regime sickle cell diagnosis using Mst II can be undertaken directly. In addition, hybridization with a cloned repetitive sequence that is of Y origin and has limited autosomal homology permits rapid fetal sexing in 3 to 4 days without compromising conventional cytogenetic or biochemical analysis. This combination of techniques provides a useful adjunct to convential prenatal genetic diagnosis in the second trimester. 相似文献
892.
The relative effectiveness of cytogenetic prenatal diagnosis in the Mersey Region and North Wales is presented by estimating the percentage detection rates of Down's syndrome annually following amniocentesis from 1978–1984 inclusive. Tables indicating the percentage of screened pregnancies, types of chromosomal aberrations detected and the occurrence of Down's syndrome in mothers in age groups of five-year intervals are also presented. The average prenatal detection rate for Down's syndrome (estimated at the time of birth) was 15–15 per cent over the years 1978–1984 and was above 22 per cent for the last two years when 44–13 per cent of all pregnancies to mothers of 35 years and over were investigated. 相似文献
893.
We report the use of fetal blood for the prenatal diagnosis of Fanconi anaemia (FA). The clastogenic action of Mitomycin C (MMC) is compared in blood cultures from different fetuses, normal controls and FA heterozygotes. The fetus at risk is shown to suffer from FA on the grounds of excessive chromosome breakage, both spontaneous and MMC induced. 相似文献
894.
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
895.
M. van Blerk MD W. Lissens M. Nijs M. van der Linden A. C. van Steirteghem I. Liebaers 《黑龙江环境通报》1991,11(8):509-512
A microfluorimetric assay was designed to monitor β-glucuronidase (β-gluc) activity during the early development of mouse embryos and was also applied to measure β-gluc activity in human sperm cells and single human oocytes. Mouse oocytes and preimplantation embryos at different stages of development, failed fertilized human oocytes, and human sperm cells were collected, and β-gluc activity was analysed. In the mouse, β-gluc activity could be measured starting from the morula stage on in a pooled sample of 15 embryos and at blasto-cyst formation in one single embryo. β-Gluc activity was low in human sperm cells. The enzyme could be readily demonstrated in 87 per cent of non-fertilized human oocytes. Considerable variation in β-gluc activity was noticed between individual oocytes. 相似文献
896.
We report the use of DNA probes to determine carrier status in three young women from a large kindred with Norrie disease. One of the women requested prenatal diagnosis during pregnancy. In this pedigree, Norrie disease was not characterized by a deletion at DXS7. 相似文献
897.
Hypospadias is one of the most prominent and characteristic midline defects in male infants with the Wolf-Hirschhorn (4p —) syndrome. In this report we present a case in which hypospadias was identified prenatally at 29 weeks' gestation in association with intrauterine growth retardation. Cytogenetic evaluation after birth confirmed a 46, XY, del(4)(p14) karyotype. The prenatal identification of hypospadias in fetuses with intrauterine growth retardation and normal amniotic fluid should suggest a diagnosis of Wolf-Hirschhorn syndrome. 相似文献
898.
The prenatal sonographic findings in a case of Walker-Warburg syndrome are described. The patient was not at risk for this condition. Ultrasound examination at 34 weeks' gestation revealed hydrocephaly, Dandy-Walker anomaly, and striking ocular abnormalities. From a review of the literature it appears that while intracranial abnormalities can lead to the diagnosis in cases at risk for this syndrome, ocular abnormalities are rather characteristic for this syndrome and they should be searched for in every case of hydrocephaly or encephalocele. 相似文献
899.
The amounts of enzyme proteins of peroxisomal β-oxidation in fibroblasts and chorionic villous cells from infants with Zellweger syndrome and in fibroblasts, amniocytes, and chorionic villi from healthy controls were measured by immunoblot analysis. Immunoreactive proteins of peroxisomal acyl-CoA oxidase and 3-ketoacyl-CoA thiolase were absent in fibroblasts and chorionic villous cells from the patients, yet these enzyme proteins were present in fibroblasts, cultured amniocytes, and chorionic villi from the normal controls. These results show that immunoblot analysis of peroxisomal β-oxidation enzymes in amniocytes and chorionic villous cells is of potential value for the prenatal detection of Zellweger syndrome. 相似文献
900.
The prenatal diagnosis of thrombocytopenia absent radius (TAR) syndrome, utilizing ultrasound and cordocentesis, is described. To our knowledge, this represents the first prenatal diagnosis of this condition in an index case. The diagnostic evaluation of a fetus with upper extremity limb reduction defects is discussed. 相似文献