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951.
肱骨干投弹骨折的分型及意义 总被引:2,自引:0,他引:2
目的 探讨投弹所致肱骨干螺旋骨折的类型及其生物力学意义。方法 分析 4 6例肱骨干投弹骨折X线片 ,测量骨折部位、长度、斜面角度和骨折的螺旋弧度等形态指标。结果 4 6例肱骨干螺旋骨折均发生于中下段 ,远近段骨折线具有对称性。骨折长度均在 30mm以上 ,以 5 1~ 90mm最多 ,共 31例 (6 7 4 % )。骨折斜面角度均≤ 4 5°,其中 4 0°~ 4 5°者 4 2例 (91 3% )。骨折螺旋角度在 2 85°~ 32 6°,平均 30 5 5°(0 85个圆周 )。 4例在骨折端内侧有一螺旋蝶形骨片。结论 肱骨干投弹骨折按形态特征分为 3种类型 ,即短螺旋、长螺旋和粉碎螺旋 ,主要发生于上臂加速期 ,由扭转暴力和纵轴压缩力引起。 相似文献
952.
本文应用多元分类分析和通路分析法研究了江苏省不同地区平均活产数的影响因素。结果表明,30年来平均活产数均是苏南低于苏北,但两地差距逐年缩小。苏南地区初婚年龄推迟1岁平均减少0.27个活产,而苏北地区可减少0.40个活产。文化水平对于平均活产数的作用也是苏北地区明显,但随着经济的发展,苏南苏北均有初婚年龄提早及平均活产数增加的现象,苏北地区更明显。 相似文献
953.
954.
Genomic technologies are rapidly evolving and have demonstrated utility inaugmenting oncological pathology or clinical presentation in disease classification and risk of relapse assessment. Numerous malignancies have been subject to microarray examination, and through a variety of analysis methodologies, groups of reporter genes have been identified to generate 'molecular portraits' of these diseases. Once validated, it is likely that assessment of the expression levels of subsets of reporter genes will contribute to personalized genomic medicine through diagnosis and selection of treatment options for patients. The dynamic nature of this field ensures that new developments are missing from this review. 相似文献
955.
螺旋CT在跟骨关节内骨折诊断中的临床意义 总被引:1,自引:0,他引:1
目的评价螺旋CT扫描对诊断跟骨关节内骨折的临床意义。方法67例临床怀疑跟骨关节内骨折患者于外伤后均经CT横轴位扫描及多平面重建。为了提供最佳手术方案,参照Sanders对骨折范围和骨碎块移位情况的分类法,推荐了一种改良的CT分型法。结果在67例跟骨关节内骨折患者中,8例(11.9%)为Ⅰ型,41例(61.2%)为Ⅱ型,以及18例(26.9%)为Ⅲ型。横轴位螺旋CT扫描及多平面重建直观、立体、清晰地显示了所有患者中跟骨关节内骨折范围、骨碎片的移位,以及受累关节面损伤情况。结论螺旋CT横轴位扫描结合多平面重建,可以准确判断跟骨关节内骨折后关节面塌陷和粉碎程度,而改良的CT分型对指导手术和评价预后具有重要意义。 相似文献
956.
957.
Cynthia Stanton MPH PhD Carine Ronsmans MD DrPH the Baltimore Group on Cesarean 《分娩》2008,35(3):204-211
ABSTRACT: Background: Cesarean delivery rates are increasing rapidly in many developing countries, particularly among wealthy women. Poor women have lower rates, often so low that they do not reach the minimum rate of 1 percent. Little data are available on clinical indications for cesarean section, information that could assist in understanding why cesarean delivery rates have changed. This paper presents recommendations for routine reporting on indications for cesarean delivery in developing countries. These recommendations resulted from an international consultation of researchers held in February 2006 to promote the collection of comparable data to understand change in, or composition of, the cesarean delivery rate in developing countries. Methods: Data are presented from selected countries, categorizing cesareans by three classification systems. Results: A single classification system was recommended for use in both high and low cesarean delivery rate settings, given that underuse and overuse of cesarean section are evident within many populations. The group recommended a hierarchical categorization, prioritizing cesareans performed for absolute maternal indications. Categorization among the remaining nonabsolute indications is based on the primary indication for the procedure and include maternal and fetal indications and psychosocial indications, required for high cesarean delivery rate settings. Conclusions: Data on indications for cesarean sections are available everywhere the procedure is performed. All that is required is compilation and review at facility and at higher levels. Advocacy within ministries of health and medical professional organizations is required to advance these recommendations since researchers have inadequately communicated the health effects of both underuse and overuse of cesarean delivery. (BIRTH 35:3 September 2008) 相似文献
958.
Automatic medical image classification is a technique for assigning a medical image to a class among a number of image categories. Due to computational complexity, it is an important task in the content-based image retrieval (CBIR). In this paper, we propose a hierarchical medical image classification method including two levels using a perfect set of various shape and texture features. Furthermore, a tessellation-based spectral feature as well as a directional histogram has been proposed. In each level of the hierarchical classifier, using a new merging scheme and multilayer perceptron (MLP) classifiers (merging-based classification), homogenous (semantic) classes are created from overlapping classes in the database. The proposed merging scheme employs three measures to detect the overlapping classes: accuracy, miss-classified ratio, and dissimilarity. The first two measures realize a supervised classification method and the last one realizes an unsupervised clustering technique. In each level, the merging-based classification is applied to a merged class of the previous level and splits it to several classes. This procedure is progressive to achieve more classes. The proposed algorithm is evaluated on a database consisting of 9100 medical X-ray images of 40 classes. It provides accuracy rate of 90.83% on 25 merged classes in the first level. If the correct class is considered within the best three matches, this value will increase to 97.9%. 相似文献
959.
960.
目的了解防城港市实施住宿业卫生监督量化分级管理的工作情况、住宿业卫生状况及存在的问题,为制定卫生监督对策提供科学依据。方法根据卫生部制定的《住宿业卫生监督量化分级评分表》,对全市所有住宿经营单位进行初评及现场指导后进入正式评审,确定卫生信誉度等级。结果全市共有263家住宿经营单位参加量化分级管理正式评审,评上C级以上卫生信誉度等级共146家,量化率为55.51%;扣分较多的项目为布草间环境、保洁设施、清洁工具、自查记录及清洗消毒等。结论应加强宣传培训,强化社会监督,完善公共场所法律法规,加大处罚力度,增强经营单位自律意识,提高公共场所卫生质量。 相似文献