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Fetal diagnosis prompts the question for fetal therapy in highly selected cases. Some conditions are suitable for in utero surgical intervention. This paper reviews historically important steps in the development of fetal surgery. The first invasive fetal intervention in 1963 was an intra-uterine blood transfusion. It took another 20 years to understand the pathophysiology of other candidate fetal conditions and to develop safe anaesthetic and surgical techniques before the team at the University of California at San Francisco performed its first urinary diversion through hysterotomy. This procedure would be abandoned as renal and pulmonary function could be just as effectively salvaged by ultrasound-guided insertion of a bladder shunt. Fetoscopy is another method for direct access to the feto-placental unit. It was historically used for fetal visualisation to guide biopsies or for vascular access but was also abandoned following the introduction of high-resolution ultrasound. Miniaturisation revived fetoscopy in the 1990s, since when it has been successfully used to operate on the placenta and umbilical cord. Today, it is also used in fetuses with congenital diaphragmatic hernia (CDH), in whom lung growth is triggered by percutaneous tracheal occlusion. It can also be used to diagnose and treat urinary obstruction. Many fetal interventions remain investigational but for a number of conditions randomised trials have established the role of in utero surgery, making fetal surgery a clinical reality in a number of fetal therapy programmes. The safety of fetal surgery is such that even non-lethal conditions, such as myelomeningocoele repair, are at this moment considered a potential indication. This, as well as fetal intervention for CDH, is currently being investigated in randomised trials. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Open fetal surgery through a wide hysterotomy is no longer a real option for prenatal intervention, but a minimally invasive approach has emerged as treatment for a small number of indications. Endoscopic ablation of placental vessels is the preferred treatment for severe twin-to-twin transfusion syndrome and it may be the only chance to salvage the most severe forms of congenital diaphragmatic hernia. Several other indications are currently under review and may become justified in the future, provided that diagnostic accuracy and patient selection become more accurate. Before invasive fetal intervention becomes widely accepted, however, we need to better define outcome. It is no longer acceptable to express results in terms of survival at birth. Survival at discharge and long-term morbidity must be considered as well. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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在脱贫攻坚的大背景下,社会工作专业力量积极参与农村精准扶贫,资源整合是其中的一个重要议题。当前农村贫困对象的资源呈现总体匮乏、资源无联动、资源流失的状态。在农村精准扶贫中,社会工作资源整合需要使贫困对象碎片化的资源状态能够系统化。开展社会工作资源整合,首先需要评估贫困对象的资源需求,然后盘点贫困对象现有资源,并优化资源输送机制,再次需要对整合的资源进行管理与评估。在农村精准扶贫中,也需要反思社会工作资源整合的本土化问题,以及思考后扶贫时代如何针对农村相对贫困群体开展社会工作资源整合服务。  相似文献   
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Impact assessment (IA) is an instrument that is gradually making inroads into European Union policy making. Great ambitions are tied to the introduction of a compulsory system of IA as a way to achieve better regulation but also as a tool to improve legitimacy of government and increase unity in European politics. In order to raise the quality of the assessments, which has been questioned, there is a call for application of more evidence-based methods. As a result, there might be a window of opportunity for greater use of scientific support in impact assessment work.However, the EC's IA system has several overlapping and partly contradictory objectives – to produce estimates about possible future impacts is only one of them. The IA system should be understood as a political instrument shaped by its multiple objectives and the political context of permanent negotiations in which it is situated.The arguments put forward emanate from a close reading of EC documents concerning IA procedures and the ambitions they display paired with assessment practices as revealed in interviews with officials in the main EU institutions, trying to perform IAs and to cope with the political balancing act they are embedded in.  相似文献   
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The metabolism of 14C-clodinafop-propargyl (CfP) was examined in cell cultures of wheat (Triticum aestivum L. cv. ‘Heines Koga II’) and tobacco (Nicotiana tabacum L.). Besides the non-transgenic tobacco culture, cultures transformed separately with cDNA of human cytochrome P450-monooxygenases (P450s) CYP1A1, CYP1A2, CYP3A4, CYP2B6 and CYP2C19 were examined. Experiments with wheat were executed in the presence and absence of safener cloquintocet-mexyl (CqM). After 48 h of incubation, only about 10% of applied 14C was found in media (both tobacco and wheat). Non-extractable residues of 14C-CfP in wheat cells were 16.54% (without CqM) and 30.87% (with CqM). In all tobacco cultures, 82.41–92.46% of applied radioactivity was recovered in cell extracts. In contrast to wheat, non-extractable residues amounted only to 1.50–2.82%. As determined by radio-thin layer chromatography (TLC) and -high-performance liquid chromatography (HPLC), the parent CfP was not found in the cell extracts of wheat; in tobacco cell extracts, only traces of CfP were detected. After a hydrolysis of assumed carbohydrate conjugates of CfP derived polar 14C-labeled compounds, TLC and HPLC analysis showed that in wheat, a more complex pattern of metabolites of CfP were observed as compared to all tobacco cultures. In hydrolysates resulting from wheat, the identity of three primary products was confirmed by means of GC-EI-MS: free acid clodinafop (Cf), hydroxy-Cf hydroxylated at the pyridinyl moiety, and 4-(5-chloro-3-fluoropyridin-2-yloxy)phenol. In hydrolysates derived from all tobacco cultures, main metabolite was Cf besides only traces of further unidentified products. Differences among the different tobacco cultures (non-transgenic, transgenic) did not emerge. According to kinetics of disappearance of primary metabolite Cf as well as formation of polar soluble products and non-extractable residues, metabolization of CfP proceeded at a noticeably higher rate in wheat cells treated with safener CqM than in cells without CqM treatment. Thus, these results indicated a stimulation of CfP's metabolism by CqM, although metabolic profiles observed in CqM treated and non-treated cells (after hydrolysis) were qualitatively similar. The findings obtained from all tobacco cultures suggested that with the exception of ester cleavage to Cf, CfP cannot be metabolized by tobacco itself or by the human P450s examined.  相似文献   
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