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排序方式: 共有2227条查询结果,搜索用时 15 毫秒
1.
Nuria Infante-Torres Milagros Molina-Alarcón Ana Rubio-Álvarez Julián Rodríguez-Almagro Antonio Hernández-Martínez 《Women and birth : journal of the Australian College of Midwives》2018,31(5):e318-e324
Aim
To assess the relationship between the duration of the second stage of labour and postpartum anaemia during vaginal birth.Methods
An observational, analytical retrospective cohort study was performed at the “Mancha-Centro Hospital” (Spain) during the 2013–2016 period. Data were collected from 3437 women who had a vaginal birth. Postpartum anaemia was defined as a haemoglobin level below 11 g/dL at 24 h postpartum. A univariate analysis was used for potential risk factors and a multivariate analysis with binary logistic regression to control for possible confounding factors.Findings
The incidence of postpartum anaemia was 42.0%. The risk of postpartum anaemia did not increase in nulliparous women whose duration of the second stage of labour exceeded 4 h. Compared with multiparous women who delivered between 0 and 3 h, multiparous women with a duration of the second stage of labour beyond 3 h were at higher risk of postpartum anaemia (OR = 2.43 [1.30–4.52]).Conclusion
The duration of the second stage of labour beyond 4 h is safe for postpartum anaemia in nulliparous women. However in multiparous women, monitoring should increase if the second stage of labour exceeds 3 h given the increased risk of postpartum anaemia. 相似文献2.
卢迪 《佳木斯大学社会科学学报》2015,33(1):104-106
咒语现象是《麦克白》整出戏剧极富魅力的表现元素。它既为剧本奠定了一种神秘而阴森的基调,同时确定全局总纲,为剧情发展起到重要的推动作用。咒语与主人公的性格、行为以及内心活动、命运走向息息相关,并最终导致麦克白命运悲剧的发生。集众恶于一身的女巫是咒语现象的主体,艰深晦涩、言辞激烈的诗体是咒语的具体表现形式,咒语的预言性质笼罩全篇,影响着人物的内心恶念,推动剧情发展,成为贯穿全剧始终的主题线索。 相似文献
3.
莎士比亚作为文艺复兴时期杰出的戏剧家和诗人,在欧洲文学史上占有重要的地位,由于莎士比亚的文学地位,使得学术界多以一种崇拜的眼光去解读其作品,而其作品中一些细微之处流露的情绪却很少被人们发觉。男同性恋文学的书写在莎士比亚的作品中对这一命题的表现的十分隐晦,通常欲言又止,但我们还是可以在其作品中发现一些蛛丝马迹。本文旨在通过分析其作品《威尼斯商人》与《莎士比亚十四行诗》来对其作品中所体现的同性化创作倾向与其同性取向倾向进行一些探究。 相似文献
4.
5.
Serra Sónia R. Q. Calapez Ana Raquel Simões Nuno Eduardo Sá Marques José A. A. Laranjo Maria Feio Maria João 《Urban Ecosystems》2019,22(6):1173-1186
Urban Ecosystems - Urban streams provide important ecosystem services to cities’ population, from the maintenance of urban biodiversity, temperature, humidity and air quality to improving... 相似文献
6.
自新冠肺炎疫情发生以来,快递业为应急救援物资和人民群众日常基本生活物资运输和寄递服务、畅通经济循环、满足民生需要等方面做出了重要贡献,为疫情防控提供了强有力的支撑;但同时也暴露出了一些问题,集中体现在末端配送体系不健全、末端收投不畅等方面。在对电子商务和快递业发展现状进行分析的基础上,对快递末端配送的主要模式和发展趋势进行了论述,结合重庆市的实际情况,分析了其末端配送存在的不足,并从公共服务平台搭建、智能化无接触式配送构建、乡村快递服务网络完善、快递员队伍建设等方面提出了对策建议,以助推重庆经济社会高质量发展。 相似文献
7.
A graph is locally irregular if the neighbors of every vertex v have degrees distinct from the degree of v. A locally irregular edge-coloring of a graph G is an (improper) edge-coloring such that the graph induced on the edges of any color class is locally irregular. It is conjectured that three colors suffice for a locally irregular edge-coloring. In the paper, we develop a method using which we prove four colors are enough for a locally irregular edge-coloring of any subcubic graph admiting such a coloring. We believe that our method can be further extended to prove the tight bound of three colors for such graphs. Furthermore, using a combination of existing results, we present an improvement of the bounds for bipartite graphs and general graphs, setting the best upper bounds to 7 and 220, respectively. 相似文献
8.
The widely used empirical Bayes (EB) and full Bayes (FB) methods for before–after safety assessment are sometimes limited because of the extensive data needs from additional reference sites. To address this issue, this study proposes a novel before–after safety evaluation methodology based on survival analysis and longitudinal data as an alternative to the EB/FB method. A Bayesian survival analysis (SARE) model with a random effect term to address the unobserved heterogeneity across sites is developed. The proposed survival analysis method is validated through a simulation study before its application. Subsequently, the SARE model is developed in a case study to evaluate the safety effectiveness of a recent red‐light‐running photo enforcement program in New Jersey. As demonstrated in the simulation and the case study, the survival analysis can provide valid estimates using only data from treated sites, and thus its results will not be affected by the selection of defective or insufficient reference sites. In addition, the proposed approach can take into account the censored data generated due to the transition from the before period to the after period, which has not been previously explored in the literature. Using individual crashes as units of analysis, survival analysis can incorporate longitudinal covariates such as the traffic volume and weather variation, and thus can explicitly account for the potential temporal heterogeneity. 相似文献
9.
10.
Existence and Nash implementation of efficient sharing rules for a commonly owned technology 总被引:2,自引:0,他引:2
Suppose that a group of individuals owns collectively a technology which produces a consumption good by means of a (possibly
heterogeneous) input. A sharing rule associates input contributions with a vector of consumptions that are technologically
feasible. We show that the set of allocations obtained by any continuous sharing rule contains Pareto efficient allocations.
We also present a mechanism that implements in Nash equilibrium the Pareto efficient allocations contained in an arbitrary
sharing rule.
Received: 29 June 1998/Accepted: 15 November 2000 相似文献