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121.
122.
E. Keller Dipl.-Biol. A. Andreas S. Scholz H. C. Dörr D. Knorr E. D. Albert 《黑龙江环境通报》1991,11(11):827-840
In 19 pregnancies at risk for 21-hydroxylase deficiency (21OHD) in 18 families with at lea one affected child, prenatal diagnosis was performed by RFLP analysis using the enzymi Taq I and EcoRI and the DNA probes specific for the 21 OH genes, the closely linke complement C4 genes and the highly polymorphic HLA class II genes DRB, DQB, and DPI For fetal DNA analysis either chorionic villi or cultivated amniotic cells were used. In all 1 cases, a clear prenatal diagnosis was possible either with the 21OH probe alone or in mo cases, by combining the results of the different closely linked loci. 相似文献
123.
Arie Drugan Anne Greb Mark Paul Johnson Eric L. Krivchenia Wendy R. Uhlmann Kamran S. Moghissi Mark I. Evans MD 《黑龙江环境通报》1990,10(8):483-490
Parental decisions concerning the continuation of pregnancy following prenatal detection of abnormal chromosomes were evaluated for 80 patients whose diagnosis and prenatal counselling were performed in our centre. Twenty-two anomalies were diagnosed by chorionic villus sampling (CVS) and 58 by amniocentesis. The severity of the chromosome anomaly and associated ultrasound findings in the first vs. second trimester were correlated with patients' decisions. No difference was found in the likelihood of parental decisions to interrupt or continue a pregnancy between CVS and amniocentesis for either the‘severe’ or the‘questionable’ group of chromosome anomalies. Ninety-three per cent of patients with severe prognosis and 27 per cent with questionable prognosis opted for pregnancy termination (p <0·0001). The association of ultrasound anomalies and termination was highly significant (p< 0·001). The severity of the chromosome anomaly, and, to a lesser extent, the visualization of anomalies on ultrasound were the major determinants of parental decisions to terminate the pregnancy. The diagnosis of an anomaly in the first trimester was no more likely ito lead to a termination of pregnancy than in the second trimester. 相似文献
124.
A. Caruso A. Lanzone V. Bianchi M. Massidda M. P. Castelli A. M. Fulghesu Professor S. Mancuso 《黑龙江环境通报》1987,7(1):41-50
The efficacy of the insulin infusion pump (CSII) in pregnancy was examined in 12 diabetic patients and compared with intermittent insulin therapy (IIT). In patients poorly controlled on IIT constant and rapid equilibrium was achieved with CSII (mean of glucose levels: CSII versus IIT=84 versus 137 mg/dl; S.D. = 36 versus 63 mg/dl; mean amplitude of glycemic excursion (MAGE)=65 versus 112 mg/dl. In patients well controlled on IIT, CSII led to a reduction in the variation of glucose excursions (S.D.= 29 versus 36 mg/dl; MAGE=48 versus 76 mg/dl). CSII generally produced a reduction of 20–37 per cent of daily insulin dose (in three cases there was an increase of dose with the achievement of glycemic control). Furthermore in CSII treated-patients amniotic glucose, insulin and C-peptide concentrations werefound tobeinthenormalrange(22.1±10.1 mg/dl; 5.2±2.7μ/ml; 1.25±0.71 ng/ml, respectively). All infants were horn at or near-term, had no macrosomia or neonatal problems. It is concluded that CSII is a highly efficient way to achieve normal glucose levels in pregnancy, not only in type I, hut also in type II or gestational diabetes. 相似文献
125.
Gross scoliosis of the fetal thoracic spine was diagnosed at 18 weeks gestation. The pregnancy was terminated and the fetus found to have webbing of the neck and an imperforate anus in addition to vertebral defects. 相似文献
126.
Prenatal diagnosis in a kindred with the Opitz (BBB) syndrome is presented. The inheritance is consistent with either autosomal dominant inheritance with sex limited expression or X-linked inheritance. The abnormalities in the kindred consist of hypertelorism, hypospadias, ambiguous genitalia, urocolic fistula, imperforate anus, mental retardation, diaphragmatic hernia, and malrotation with volvulus. A male fetus at 19 weeks was found by ultrasound to have hypertelorism and hypospadias with a small phallus consistent with the syndrome. The diagnosis was confirmed by pathologic examination after pregnancy termination. This is the first report of prenatal diagnosis of Opitz syndrome by ultrasonographic demonstration of hypertelorism and hypospadias in the second trimester. 相似文献
127.
Prenatal diagnosis in a pregnancy at risk for a juvenile B1 variant of GM2-gangliosidosis was carried out. The biochemical study of the cultured amniocytes and the affected fetal brain is reported. The results obtained show that the sulphated artificial substrate can be used in the diagnosis of B1 variant, but not the neutral one. The accumulation of GM2-ganglioside in the fetal brain of the B1 juvenile form and an infantile form of GM2-gangliosidosis (0 variant) was compared. 相似文献
128.
Wu Jin Wang Anpu Huang Yanchu Ma ciguang Y. Ii S. Daishim K. Furuy T. Kikuchi H. Matsushit K. Tanabe 《环境科学学报(英文版)》1990,2(1):27-39
A study has been made on elements organic constituents, TSP, SO2,NO2 of atmospheric pollutants in Beijing. 17 elements, and some PAHs, e. g. B(a)P, B(b, j, k)P, and B(g, h, i)P, in airborne particles by X-ray fluorescence spectroscopy and HPLC, GC/MS, have been determined respectively. It has been shown that the elements Pb, Zn, S and Cu were more enriched in fine particles and different valence states of sulfur at various sites. It was found that the concentrations of S6+ and S2-were more than 85% and less than 15% of the total sulfur respectively. Concentrations of major PAHs and sulfur-containing compounds increased in winter and in urban area. High values for Pb and Zn in city, Fe and Mn at industrial area and Cu, Al rural sites were obtained respectively. This implies the functions of different elemental sources of various sites. Thus, elements can be from distingushed anthropogenic and natural sources.The main contribution of SO2 was found of to have same seasonal variation as the anthropogenic el 相似文献
129.
The effects of reduced oxygen concentrations in the gas phase over the culture medium on colony formation and cell proliferation were investigated in high and low cell density primary and secondary cultures of amniotic fluid cells. Using two standard culture methods (25 cm2 plastic flasks and Leighton type tubes) a significantly reduced culture time was observed at high cell density for mass cultures by incubation within a low oxygen tension gas phase (2.5 per cent to 7.5 per cent O2) instead of conventional air (18 per cent O2). At low cell density colony formation was significantly enhanced in cultures grown at reduced oxygen tension. Using gas permeable membranes as support, lowering the oxygen tension from 7.5 per cent to 2.5 per cent yielded an increase in plating efficiency of cells from approximately 5 per cent to 25 per cent, whereas plating efficiency was less than 2 per cent for cells grown at ambient 18 per cent O2. It is suggested that low oxygen tension in the gas phase is an effective means of enhancing clonal growth in amniotic fluid cell cultures, thereby reducing both culture time and risk of culture failure. 相似文献
130.
To gain an understanding of the characteristics of the needle surfaces of naturally regenerated Scots pine (Pinus sylvestris L.) and their geographical distribution, eight physicochemical variables were investigated within the north boreal forest area. The visibly undamaged needles were collected in autumn 1990 from 114 plots (3-5 pines per plot) along radial transects from the Monchegorsk and Nikel smelters, emitting SO2 and heavy metals, on the Kola Peninsula, Russia, to Finnish Lapland. The needles were examined by scanning electron microscopy (SEM) and measured for surface wettability using the droplet contact angle (DCA) method. Significant geographical south-north and west-east patterns could be observed in needle surface characteristics, correlating with emissions from the smelters and to climate. Despite the slightly higher initial DCAs (61.4-87.6 degrees) towards the north, the pine needle surfaces of the northernmost transects exhibited higher annual needle wettability change (ANWC) and wax erosion rate (AWER), expressed as the reduction in DCAs and epistomatal wax tube distribution (WTD) during one year, respectively, but a lower occurrence of particles and fungal hyphae than those of more southern transects. The higher ANWC was related to higher atmospheric SO2 concentration, and to the lower long-term temperature sum, but not clearly to annual precipitation. In the Monchegorsk smelter area, the current needles exhibited, on average, a 15% higher WTD and seven degree larger DCA, resulting in more hydrophobic needle surfaces than in Finnish Lapland, but during their first year, both the AWER and ANWC, were greatly increased. In Finnish Lapland, 30%, of all the epistomatal wax tubes disappeared from the needle surface during the first year, the value being 70% for the pines located 8 km from the smelter. The mineral composition of the particles deposited on the needle surfaces mirrored that of the minerals being produced by the smelters (e.g. FexSx, CuFeS2, NixSx, FexOx). Stomatal densities were in the range of 71.1-141.7 stomata mm(-2). The lower densities of stomata on needles close to the smelters correlated with reduced number of needle age classes of the pines, higher dry weights, higher pollutant accumulation and lower Mn and Zn concentrations in the needles. The AWER and ANWC were able to indicate the most seriously deteriorated needle surfaces on a regional scale, e.g. including the surroundings of both smelters, although the plot-specific relationships between 'needle surface variables' and 'pollution variables' were generally weak. The present study showed that the exposure of pine needles to the combined effects of ambient pollutants and harsh climate led to a deterioration in the physicochemical characteristics of the epicuticular wax, which may have serious ecophysiological consequences in the long term. 相似文献