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201.
Françoise Muller Didier Thibaud Françoise Poloce Marie-Christine Gelineau Marguerite Bernard Christine Brochet Christine Millet Jean-Yves Réal Marc Dommergues 《黑龙江环境通报》2002,22(11):1036-1039
In routine obstetrical practice, prior to offering invasive prenatal diagnosis, it is crucial to weigh the risks attendant on amniocentesis against the individual's risk of aneuploidy. We took advantage of a policy of follow-up of patients undergoing Down syndrome maternal serum screening to compare the rates of fetal loss before 24 weeks and of early premature delivery at 24–28 weeks between women who underwent amniocentesis and women who did not. A total of 54 902 patients entered the study, of whom 4039 (7.35%) were lost to follow-up and 387 were excluded because of a severe fetal abnormality. Of the 50 476 remaining patients, 3472 had an amniocentesis whereas 47 004 had not and served as controls. In the amniocentesis group, the fetal loss rate before 24 weeks was 1.12% (95% CI=1.08–1.15) and the 24–28 weeks premature delivery rate was 0.40% (95% CI=0.39–0.41) which was significantly higher than in controls (0.42% with 95% CI 0.41–0.43 and 0.24% with 95% CI 0.23–0.25, respectively). The 0.86% difference in adverse outcome rates between the amniocentesis and control groups may be attributable to amniocentesis and compares favourably with the positive predictive value of maternal serum markers (1.70%) observed in the present study. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Congenital heart disease (CHD) is one of the commonest prenatal diagnoses made on routine ultrasound screening. Overall, up to 33% of CHD are associated with fetal aneuploidy. However, some specific cardiac lesions have a significantly greater association with particular chromosomal abnormalities. The majority of fetuses with CHD and aneuploidy also have extra-cardiac anomalies and are best managed by a multidisciplinary team where the management and prognosis of the cardiac defect can be discussed in the context of the baby as a whole. It is therefore important for clinicians involved in the management of fetuses with CHD to be aware of the association of aneuploidy as well as the prognosis and management of these cases, so that they can appropriately counsel the parents. In this chapter, we review the frequency and types of aneuploidy associated with the commonly diagnosed CHD and discuss their management. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Guo Risheng 《中国人口.资源与环境(英文版)》2012,10(2):3-11
This paper summarizes, from a global perspective, the major progress in the implementation of the Agenda 21 since the UN Conference on Environment and Development. The results show that global economy has achieved a substantial growth, and positive progress has been made in poverty eradication, urbanization, and conservation and intensive use of natural resources. However, relevant international conventions and commitments have not yet been completely fulfilled. The paper further analyzes the current major challenges and future trends of global sustainable development. It is argued that there are three major challenges:1) fatal global environmental issues posing an increasing threat to human survival; 2) more and more severe global competition for developing spaces; and 3) issues highlighting global people’s livelihood. There are four trends of global sustainable development:1) sustainable development will further turn from concept into global action; 2) green will be the main trend of global development; 3) emerging developing countries will become the main driving force of global sustainable development; and 4) international relations in the field of sustainable development will turn to competitive co-operation. 相似文献
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David Humphreys 《Resources Policy》2011,36(2):142-148
As Russia’s largest mining company, Norilsk Nickel was for much of its history an archetypal Soviet institution. Following the collapse of the Soviet Union and the subsequent prolonged economic crisis, in 2001 new management came into the company with the objective of transforming the company into a modern global corporation. In the years that followed, management pushed through a series of radical changes to the organisation and its operations. Simultaneous with these changes, the company extended its asset base in Russia and acquired assets outside the country. The progressive direction of the company was, however, taking it further and further out on a limb and the programme of transformation was not being matched and supported by public policy and regulation. Pressures came to a head in the middle of 2008 when a change in the structure of company’s ownership and a collapse of metal prices combined to bring about increased involvement of the state in company’s affairs and a more national emphasis to its strategic orientation. 相似文献
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