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931.
Dr. Elizabeth J. T. Winsor B. St. John Brown Edwin R. Luther Stephen A. Heifetz J. Philip Welch 《黑龙江环境通报》1987,7(7):485-489
A pregnancy was terminated because of persistently elevated amniotic fluid AFP (+10 S.D.) and an AChE band of low intensity on gel electrophoresis. No fetal anomalies were detected by ultrasonographic examination. Autopsy revealed an apparently normal fetus of about 20 weeks gestation. Attached to the placenta was a small sac containing a fetus papyraceus co-twin of about 8–9 weeks gestation. The small deceased co-twin and its gestational sac were not detected prenatally despite multiple ultrasonographic examinations. The difficulty in the interpretation of apparently conflicting results is emphasized. 相似文献
932.
In 226 women requesting chorionic villus sampling (CVS), routine cervical cultures were obtained before the procedure. Transcervical CVS was performed irrespective of the test results. The prevalence of potential pathogens in cervical cultures at our institution is low. Beta haemolytic Streptococcus was cultured in 3 per cent of the women. No pathogenic microorganisms were isolated in 64 per cent of the women. There was no relationship between culture results and the outcome of pregnancy. These observations suggest that adequate antiseptic cleansing of the genital tract is a suitable approach and there is no need to routinely perform cultures before CVS. 相似文献
933.
Dr Sara Ahmed 《The Environmentalist》1994,14(1):3-16
Summary People's participation is usually regarded as a sine qua non for the success and sustainability of development projects. Yet in practice, it raises a number of questions. Who are the people? Why is their participation sought, and how or at what level, is such participation desired? This paper seeks to examine the rhetoric of participation in the implementation of the Ganga Action Plan (GAP) at Varanasi, in the north-eastern State of Uttar Pradesh, India. Launched in 1985, the GAP is the first major attempt to systematically control and monitor the pollution of a significant river in the country. In addition, it claimed to be a people's programme because of the powerful and deep-seated cultural and religious meaning associated with the Ganga. Varanasi, however, is indicative of its failure to deliver this promise — the GAP is only acceptable to authority because it does not challenge the existing institutional order, and its participatory content is symbolic rather than substantive. Non-govemental organisations, traditionally viewed as intermediary actors between the micro and macro levels, work within the socio-political framework of the city. In the process, water-user groups such as the washermen who derive an economic livelihood from washing clothes in the Ganga, are literally excluded from the definition and process of participation.She obtained her PhD, the basis of the current research, at the University of Cambridge, UK. 相似文献
934.
The role of light in induction of sexual maturation in male Octopus vulgaris has been studied on experimentals reared in the laboratory. Experiments were carried out during January, February and March, the time of the year when females do not breed or are just beginning to breed. Males (20 to 500 g) were artificially illuminated for 8 or 16 h/day or kept in complete darkness. Their gonads were compared with those of wild specimens killed a few hours after capture. In the Mediterranean Sea, under natural conditions, O. vulgaris males of less than 150 g never display sexual maturity; under our experimental conditions, young males from 70 g onwards, illuminated 16 h daily, show gonad development. Males of over 150 g, illuminated 16 h daily, have a larger number of spermatophores than wild specimens of individuals illuminated 8 h daily. O. vulgaris reared in complete darkness are sexually more mature than wild individuals. An hypothesis on induction of sexual maturation in the Cephalopoda is proposed. 相似文献
935.
Five hundred cordocenteses were performed between 12 and 21 weeks. The indications were thalassaemia (386), rapid karyotyping (97), feto-maternal allo-immunization (10), rubella (6), and toxoplasmosis (1). One hundred and ten pregnancies underwent termination on the basis of the result, while 20 of the 370 pregnancies intended to continue were lost to follow-up. Amongst these were 16 fetal losses (4·3 per cent) and 22 premature deliveries (5·9 per cent); no other complications were reported. Four adverse prognostic factors were identified: (a) cord bleeding; (b) fetal bradycardia; (c) prolonged procedure time; and (d) anterior insertion of the placenta. There was no‘obvious’ difference in fetal loss rate with advancing gestation until 19–21 weeks, when the risk of fetal loss decreased to 2·5 per cent. 相似文献
936.
Dr Christopher J. Danpure Patricia R. Jennings Richard J. Penketh Pauline J. Wise Penelope J. Cooper Charles H. Rodeck 《黑龙江环境通报》1989,9(4):271-281
Primary hyperoxaluria type 1 (PH1) is caused by a deficiency of the hepatic peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT, EC 2.6.1.44) (Danpure and Jennings, FEBS Lett., 201 , 20–24, 1986). The activity of AGT has been measured in fetal livers of gestational age 14–21 weeks. Activity increases up to 17 weeks and then levels off between 17 and 21 weeks. At this time, the mean AGT activity is about 30 per cent of the mean normal postnatal level. As in adult liver, the AGT enzyme activity and the AGT immunoreactive protein are peroxisomal. Prenatal diagnosis has been performed by measuring AGT enzyme activity and immunoreactive AGT protein on liver biopsies from two fetuses at risk for primary hyperoxaluria type 1. One was unaffected and one was affected. 相似文献
937.
A large number of chorionic villi samples obtained from women undergoing elective first trimester termination of pregnancy was analysed by enzyme assays similar to those applied to cultured amniotic cells. The levels of 15 lysosomal enzymes were compared to those observed in tissue cultures of amniotic cells obtained through amniocentesis at 16-18 weeks of pregnancy and the results were discussed in order to assess the usefulness of trophoblast biopsy for first trimester diagnosis of hereditary lysosomal diseases. The data suggest the applicability of this source of fetal cells for prenatal diagnosis of fifteen respective genetically determined enzyme deficiencies with the probable exception of α-L -iduronidase deficiency. Enzyme determinations were performed on chorionic villi samples of two pregnancies at risk for Tay-Sachs disease, three pregnancies for GM1 gangliosidosis type 1, one for mucopolysaccharidosis type VI and one for Wolman's disease. 相似文献
938.
Three hundred and thirty-nine cases of multiple gestation underwent prenatal diagnosis by amniocentesis. The spontaneous abortion rate (to 28 weeks) in this group was 3.57 per cent compared with our singleton abortion rate of 0.60 per cent. The perinatal mortality rate (PMR) and prematurity rate were not different from the singletons, and compared favourably with the PMR reported in the literature for multiple gestations which did not undergo any intervention during pregnancy. This increased abortion rate following amniocentesis may only represent the increased natural loss rate in multiple gestations, and not indicate any increased risk added by the procedure. 相似文献
939.
Dr. R. L. Anderson M. S. Golbus C. J. R. Curry P. W. Callen W. H. Hastrup 《黑龙江环境通报》1990,10(8):513-518
Four cases of multiple gestation with second trimester death of one fetus and subsequent damage to a survivor are reported. Monochorionic placentation was documented in three of the cases. Central nervous system lesions occurred in all cases, and bowel injury was noted in two of the damaged fetuses. Although rare maternal clotting problems have been reported in similar situations, none was noted in any of these four cases. Prior reports have indicated that losses in the first half of gestation were of no consequence to the surviving fetuses. These four cases contradict this suggestion, and indicate that close sonographic observation of the survivors is important in any multiple gestation where one fetus has died. 相似文献
940.
Dr. J. J. Waters M. E. Ferguson-Smith N. Carter J. L. Alexander S. V. Hodgson 《黑龙江环境通报》1990,10(10):677-681
Prenatal diagnosis, by amniocentesis, revealed mosaicism with respect to a bisatellited, apparently dicentric, DA/DAPI positive, de novo marker. The following cell lines were observed in decreasing order of frequency: 46,XX > 48.XX, + mar, + mar » 47,XX, + mar. The pregnancy was terminated and post-mortem examination revealed an apparently normal fetus. Cytogenetic studies of fetal and placental tissues revealed approximately the same level of mosaicism together with the unusual copy number ratio seen in the amniotic fluid cultures. Non-disjunction at the first post-zygotic mitotic division giving rise to a mosaic: 46,XX/ 48,XX, + mar, + mar followed by subsequent mitotic instability of the marker could account for the unusual copy number ratio. 相似文献