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241.
Dr. Susanna Bunge Cordula Steglich Peter Lorenz Michael Beck Suying Xu John J. Hopwood Andreas Gal 《黑龙江环境通报》1994,14(9):777-780
Identification of iduronate-2-sulphatase (IDS) gene mutations in patients with mucopolysaccharidosis type II (MPS II, Hunter syndrome) allows fast and reliable carrier detection and prenatal diagnosis. We describe here three cases of prenatal diagnosis by direct detection of the gene mutation. In addition to two affected male fetuses from two different families, a 47,XXY fetus carrying both the normal and the mutant allele was diagnosed in a third family. The latter pregnancy was carried to term and the child is obviously not affected by MPS II. 相似文献
242.
We describe a rare case of non-immune hydrops fetalis caused by mediastinal teratoma. The sonographic appearance was that of a mixed cystic and solid mass in the antero-superior mediastinum. The teratoma, on post mortem, extended cranially to the upper part of the thyroid, exerting pressure and causing deviation of the trachea, oesophagus, and aortic arch. The pathogenesis of non-immune hydrops fetalis suggests obstruction of venous return caused by this tumour. 相似文献
243.
The history of amniocentesis utilization in the seventh largest state of the United States is documented from its inception in 1972 through the first half of 1984. Amniocentesis utilization ratios for Ohio residents aged ⩾35 have increased from 0.21 per cent (19/9091) in 1972 to 23.4 per cent (1655/7531) in 1983, representing an average annual growth rate of 43.1 per cent. Of the amniocenteses performed from January 1, 1978–July 1, 1984, 71 per cent were referred for advanced maternal age (⩾35), 15 per cent for maternal anxiety (30–34), 10 per cent for family history or previous child with a genetic defect, and 4 per cent for other reasons. Between 1978-1983 utilization by women 45 years of age was only 20 per cent higher than women 35 even though their risk of giving birth to a Down syndrome child was about one order of magnitude higher. In addition, various factors were tested as to whether they affected utilization of amniocentesis by women ⩾35 during 1978 1983. A strong correlation of +0.89 existed between county population size and utilization ratios. No difference in utilization was found between whites and nonwhites, regardless of county population size. When utilization ratios were compared separately between Protestants, Catholics and other religions in Ohio's most populated county, no statistical differences were found. From 1978–July 1, 1984, the frequency of all cytogenetically abnormal chromosome results observed in Ohio amniocenteses to women ⩾35 was 2.48 per cent (187/7536). Of these, 2.15 per cent (162/7536) had unbalanced karyotypes. Future maximum amniocentesis utilization for women ⩾35 is estimated at 60–70 per cent. 相似文献
244.
Jiaen Liu Dr Willy Lissens Paul Devroey Andre Van Steirteghem Ingeborg Liebaers 《黑龙江环境通报》1993,13(9):873-880
The efficiency of the polymerase chain reaction (PCR) in detecting the cystic fibrosis (CF) ΔF508 mutation (which is the most common mutation of CF) was assessed in single human blastomeres. Twenty-one human immature oocytes (germinal-vesicle-stage oocytes) that had been donated for research were matured in vitro and a single spermatozoon from a carrier of the CF ΔF508 mutation was injected into the ooplasm. Fourteen embryos were obtained after intracytoplasmic sperm injection (ICSI). PCR analysis was carried out on 70 single blastomeres isolated from these 14 embryos. The results showed that the efficiency of DNA amplification by PCR in single nucleate blastomeres was 94 per cent (59/63). There were no false-positive results since none of the blank samples or the blastomeres without a nucleus showed an amplified signal. We found that nine embryos were homozygous for the unaffected genotype and that four embryos were heterozygous since they contained both the unaffected and the ΔF508 genotype. In a four-cell embryo, we observed the homozygous unaffected genotype in one blastomere and a heterozygous ΔF508/unaffected genotype in the other three blastomeres. 相似文献
245.
246.
Dr R. J. Morrow M. J. Whittle Margaret B. McNay P. A. M. Raine A. A. M. Gibson Jenny Crossley 《黑龙江环境通报》1993,13(2):111-115
An attempt was made to identify all the cases of abdominal wall defects occurring in the West of Scotland over a 7-year period to determine the current incidence, prenatal diagnosis, management, and prognosis for fetuses and neonates with abdominal wall defects. Cases were identified because they presented either for prenatal diagnosis, or to the Department of Pathology following termination or spontaneous pregnancy loss, or as neonates to the Neonatal Surgical Department. The incidence of abdominal wall defects was found to be 1 in 2500 births. Exomphalos was diagnosed before birth in 66 per cent of cases, and in 30 per cent of cases it was associated with another major abnormality. There was a 20 per cent intact survival in the cases diagnosed prenatally who had no fetal anomaly and who opted to continue with the pregnancy. Gastroschisis was diagnosed before delivery in 70 per cent of cases, and in the group who continued with the pregnancy there was an intact survival of 77 per cent. Body stalk anomalies were all diagnosed prenatally and terminated. Maternal serum alpha-fetoprotein was elevated in 89 per cent of the cases with exomphalos and in 100 per cent of the cases with gastroschisis and body stalk anomalies in which it was tested. 相似文献
247.
Forty-two women with abnormal ultrasound findings after 27 weeks' gestation underwent a placental biopsy. In 39 cases, a karyotype was obtained from a direct preparation within 48 h, five abnormal karyotypes being detected (four trisomies and a triploidy). One confirmed placental mosaic was also detected. In one case, a small terminal deletion of chromosome 7 was not detected at the time due to the quality of the preparation. A karyotype can be obtained from a direct preparation in the third trimester in over 90 per cent of cases, the quality of the preparation allowing the reliable detection of abnormalities of chromosome number. We believe that this technique may be usefully, reliably, and safely employed in the third trimester of pregnancy by those with an interest in antenatal ultrasound diagnosis who do not have immediate access to a cytogenetics laboratory and who feel that cordocentesis is inappropriate for their situation. 相似文献
248.
Dr. D. Arduini G. Rizzo C. Giorlandino H. Valensise S. Dell'Acqua C. Romanini 《黑龙江环境通报》1986,6(2):117-124
In order to evaluate the development of fetal behavioural states a longitudinal study was performed on 35 healthy fetuses during the last trimester of pregnancy. Fetal heart rate (FHR), gross fetal body movements (FM), fetal eye movements (FEM), fetal breathing movements (FBM) and micturition were simultaneously studied at two-week intervals from 28 weeks gestation onwards. Well-defined fetal behavioural states were observed only after 36 weeks gestation. Between 28 and 36 weeks the quiet-activity cycle of FHR was always detected and some fetal biophysical activites seemed to become related around this cycle. 相似文献
249.
In a fetus with ventricular extrasystoles a congenital aneurysm of the left ventricle was diagnosed prenatally. At 32 weeks of gestation, echocardiography showed a large apical left ventricular aneurysm with a thin, hypokinetic wall. Congestive heart failure did not occur. Prenatal and postnatal examinations did not detect the aetiology of the aneurysm, but excluded the majority of possible causes. The 2-year-old child is now asymptomatic and normally developed. Neither medication nor surgical treatment have been necessary, except for antithrombotic prophylaxis with low-dose aspirin. 相似文献
250.
In order to obtain a large set of normal control values, the activities of three cytosolic enzymes of purine metabolism and seven lysosomal enzymes were determined in homogenates of chorionic villi derived from induced abortions of normal pregnancies (7th–12th week) in about 100 individual cases. Possible reasons for the rather wide ranges of normal distributions of enzyme activities are discussed. The values are compared: (1) with available data in the literature; (2) with activities determined in decidual homogenates prepared from the same samples; (3) with activities of cells of cultures established and grown from villi in the same samples; and (4) with enzyme activities measured in chorionic biopsies using the same methods. Implications for the prenatal diagnosis of the associated metabolic diseases are considered. 相似文献