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91.
BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable.  相似文献   
92.
翻开《野草》,全篇色彩瑰丽奇幻,红色、白色、黑色、青色……构成了《野草》艺术世界中独特的色彩意象体系.鲁迅笔下象征性色彩形象的选择和色彩意境的营造,不仅展示出特定历史时期自然与社会的风貌,而且传达出作者在这一时期内心深处的体验和感受.  相似文献   
93.
思想性是文学的一个显著特征,是作家的创作实践在作品中流露出来的倾向性。即便描写或叙述一件比较小的事情,里面也渗透着作家对社会、对人生、对世界的看法,同时也包含着对某种新发现的独到理解。《白鹿原》在刻画鲜明的人物形象的同时也渗透着作家对传统文化、家族文化、婚姻文化等方面的独特见解,使人们能够深深地感受到作家的文化观、历史观、人生观。  相似文献   
94.
Methods for a sequential test of a dose-response effect in pre-clinical studies are investigated. The objective of the test procedure is to compare several dose groups with a zero-dose control. The sequential testing is conducted within a closed family of one-sided tests. The procedures investigated are based on a monotonicity assumption. These closed procedures strongly control the familywise error rate while providing information about the shape of the dose-responce relationship. Performance of sequential testing procedures are compared via a Monte Carlo simulation study. We illustrae the procedures by application to a real data set.  相似文献   
95.
唐代送别诗中的意象组合极具特色,诗人巧妙利用送别时的地点、行人所往之地以及沿途的文化特色形成的空间地点意象组合,造成了峰断云连、辞断意属的审美意境;借用明显的时令节侯、景物气象等特点组合的意象,则增添了送别诗意象的斑斓色彩和艺术感染力。  相似文献   
96.
通过对藏族大学生在识记不同语言材料时表现出不同效果的分析,从信息加工的角度阐述了母语是识记的基础,是识记表象建立的关键,母语所反映的认知取向决定了识记的侧重点。  相似文献   
97.
左江花山岩画文化景观成功入选世界遗产名录后,依然有未解的千年之谜。经对左江花山岩画中铜鼓的族属、类型、传承发展、文化功能等进行多角度考证,确认左江花山岩画所绘铜鼓为骆越人所有,其类型为万家坝型、石寨山型和东山型早期铜鼓;岩画中的铜鼓不仅是部族首领权力的象征,还是通天礼神、汇聚人心、指挥军阵、人神共娱的重要礼器、响器及乐器;东汉马援缴骆越铜鼓后,左江流域骆越后裔仍有用鼓、尚鼓的习俗,这是对左江花山岩画铜鼓的一种继承与发展。与此同时,骆越人先进的青铜铸造技术亦为铜鼓在这一地区的传承与发展提供了物质基础。  相似文献   
98.
Fernando Martins 《LABOUR》2015,29(3):291-309
This paper exploits the information collected from a survey conducted on a sample of Portuguese firms to study the patterns of firms’ price and wage adjustments and the extent of nominal price and wage rigidities. The evidence shows that the frequency of price changes varies substantially across sectors and depends on the intensity of competition, the share of labor costs and firms’ price reviewing behavior. The results also suggest that the constraint imposed by the presence of downward nominal wage rigidity is less important in firms where the fraction of permanent and high‐skilled workers is lower and the share of flexible pay components is higher.  相似文献   
99.
Using data on Members of the European Parliament (MEPs), we examine the impact of salaries on the composition and the behavior of legislators. Employing a differences‐in‐differences approach, we exploit the introduction of a law that equalized MEPs' salaries which had previously differed by as much as a factor of 10. Increasing salaries raises the fraction of MEPs who run for re‐election but decreases the quality of elected MEPs (proxied by college quality). Salary has no discernible impact on effort or legislation output. Higher salaries induce more political competition.  相似文献   
100.
We measure the relative ideological positions of newspapers, voters, interest groups, and political parties, using data on ballot propositions. We exploit the fact that newspapers, parties, and interest groups take positions on these propositions, and the fact that citizens ultimately vote on them. We find that, on average, newspapers in the United States are located almost exactly at the median voter in their states—that is, they are balanced around the median voter. Still, there is a significant amount of ideological heterogeneity across newspapers, which is smaller than the one found for interest groups. However, when we group propositions by issue area, we find a sizable amount of ideological imbalance: broadly speaking, newspapers are to the left of the state‐level median voter on many social issues, and to the right on many economic issues. To complete the picture, we use two existing methods of measuring bias and show that the news and editorial sections of newspapers have almost identical partisan positions.  相似文献   
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