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Skeletal surveys (SSs) have been identified as a key component of the evaluation for suspected abuse in young children, but variability in SS utilization has been reported. Thus, we aimed to describe the utilization patterns, yield, and risks of obtaining SS in young children through a systematic literature review. We searched PubMed/MEDLINE and CINAHL databases for articles published between 1990 and 2016 on SS. We calculated study-specific percentages of SS utilization and detection of occult fractures and examined the likelihoods that patient characteristics predict SS utilization and detection of occult fractures. Data from 32 articles represents 64,983 children <60 months old. SS utilization was high (85%-100%) in studies of infants evaluated by a child protection team for suspected abuse and/or diagnosed with abuse except in one study of primarily non-pediatric hospitals. Greater variability in SS utilization was observed across studies that included all infants with specific injuries, such as femur fractures (0%–77%), significant head injury (51%–82%), and skull fractures (41%–86%). Minority children and children without private insurance were evaluated with SS more often than white children and children with private insurance despite lack of evidence to support this practice. Among children undergoing SS, occult fractures were frequently detected among infants with significant head injury (23%–34%) and long bone fractures (30%) but were less common in infants with skull fractures (1%–6%). These findings underscore the need for interventions to decrease disparities in SS utilization and standardize SS utilization in infants at high risk of having occult fractures. 相似文献
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针对精冲三维数值模拟的局限性,采用有限元软件Deform-3D建立摩擦片背板的三维精冲模型。根据Normalized Cockroft&Latham断裂准则,分析了成形过程中的静水应力、金属速度流动分布和发展趋势。通过数值模拟获得最佳冲裁间隙值为厚度的0.6%,为提高精冲件质量提供了依据。 相似文献
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罗彦祥 《宁夏师范学院学报》2007,28(6):41-44
本文着重阐述了SiCp/Al复合材料断裂韧性的影响因素,其影响因素有增强相的尺寸、形状以及含量,热处理工艺,基体与增强相具有不同的膨胀系数,金属基体的化学成份等,笔者在前人研究的基础上提出了几点设想. 相似文献
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目的 探讨邻近关节的骨化性肌炎形成的临床特点及治疗.方法 分析、总结了18例近关节处的骨化性肌炎病例,对其发病诱因、关节功能影响,神经、血管受压综合征候群进行研究,提出相应的防治方法.结果 18例近关节骨化性肌炎均有不同程度外伤史,其中12例骨折病例都有多次暴力程度不同的骨折复位史;另有6例伴随继发性神经、血管压迫症状;受累关节活动严重受限,呈僵硬状态.结论 近关节损伤形成的骨化性肌炎对关节功能影响大,对神经、血管的继发性压迫较远关节处危害大,本组病例的总结,为近关节处的骨化性肌炎防治提供借鉴经验. 相似文献
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本文讨论非金属材料在外力作用下产生的断裂类型,断裂机理和三种开裂类型的判别式,结合具体实例进行了计算,并与其它强度理论进行了对比,认为Griffith 强度理论对于非金属材料的断裂问题判据是适用的. 相似文献
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Fatigue reliability analysis of fixed offshore structures: A first passage problem approach 总被引:1,自引:0,他引:1
MADHAVAN PILLAI T.M VEENA G. 《浙江大学学报(A卷英文版)》2006,7(11):1839-1845
INTRODUCTION Offshore production and drilling platforms are, in general, large and complex structural systems, usually fabricated using steel tubular members interconnected through welded joints. These structures are predomi- nantly subjected to oscillatory environmental loads and fatigue characterizes a primary mode of failure of their components. The fatigue damage at any point in the structure depends on the complete stress history during the structure’s service life. The calculation … 相似文献
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研究目的:本文通过研究泥水在地层中的劈裂和伸展现象,给出一种地层劈裂抗力的测定方法,从而为泥水盾构掘进过程中泥水压力设定提供参考,防止盾构掘进过程中泥水喷发现象的发生。创新要点:1.给出了地层劈裂抗力的测定方法,并通过现场试验和理论分析得出该方法是可靠的;2.建立了考虑泥水粘性和比重的地层劈裂伸展模型,该模型对现场试验结果有较好的预测;3.结合地层劈裂抗力和泥水劈裂伸展特性给出了盾构掘进过程中泥水压力的设定上限。研究方法:基于现场泥水劈裂试验,通过试验结果分析和理论分析,建立了劈裂压力和劈裂伸展压力的计算模型。通过泥水和地层参数对计算模型的影响分析,给出泥水盾构掘进过程中泥水配比和压力设定选择建议。重要结论:1.本文描述的现场泥水劈裂仪可以用于地层劈裂抗力的测定;2.使用总应力法的劈裂模型能够很好的预测地层的初始劈裂压力;3.考虑泥水粘性和比重的地层劈裂伸展模型对现场试验结果有较好的预测;4.在劈裂伸展的过程中,具有更大比重和粘性的泥水有利于阻止劈裂的进一步伸展,但是对初始劈裂压力的影响不大。5.在实际盾构掘进过程中,泥水劈裂发生后很难阻止其伸展。因此,防止泥水喷发的关键措施在于设定泥水压力上限防止泥水劈裂。 相似文献
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目的:探讨严重创伤骨折患者角色适应不良的护理对策。方法:研究87例严重创伤骨折患者角色适应不良的护理对策。结果:69例患者角色适应能力很好,积极配合治疗。14例患者角色适应能力较好,情绪稳定,愿意配合治疗。4例患者角色适应能力差,对治疗和前途缺乏信心。结论:制定有效的护理干预措施可以为患者角色适应提供了良好的支持。 相似文献
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多元文化的并存必然会带来文化间的互动。澜沧江流域彝族习惯法与国家法之间既断裂又整合的关系真实地反映了民间和国家两套规范的互动状态。在当前推进依法治国和实现法治现代化的进程中,探索两者间法治资源整合的最佳路径,对促进澜沧江流域彝族社会法治真正实现本土化、现代化的转换具有重要意义。 相似文献