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991.
腰骶部SPR术中脊神经前后根定位的应用解剖 总被引:13,自引:6,他引:13
目的:为SPR提供可靠的术中脊神经前、后根鉴别的解剖学依据。方法:在20例成人脊柱标本上,去除后部结构,暴露整个马尾神经,对L1~S2节段的前后根进行形态学观察和测量。结果:脊神经后根位于马尾的后半部,前根则位于前半部。脊神经后根较相应的前根粗大,后根从L1~S1逐渐增大,以S1为最粗大;前根则以L3最粗大。相应前后根出硬脊膜前,有一段相互贴附并紧贴硬脊膜侧壁。结论:在多椎板切除SPR术中前、后根的定位及鉴别,暴露时可根据前、后根出硬脊膜前的相互贴附;在限制性椎板切除时则可通过脊髓外侧索和L1前、后根之间的最下端的齿状韧带加以鉴别 相似文献
992.
993.
Hanfei Xu Karen Schwander Michael R. Brown Wenyi Wang R. J. Waken Eric Boerwinkle L. Adrienne Cupples Lisa de las Fuentes Diana van Heemst Oyomoare Osazuwa-Peters Paul S. de Vries Ko Willems van Dijk Yun Ju Sung Xiaoyu Zhang Alanna C. Morrison D. C. Rao Raymond Noordam Ching-Ti Liu 《European journal of human genetics : EJHG》2021,29(5):839
Recent studies consider lifestyle risk score (LRS), an aggregation of multiple lifestyle exposures, in identifying association of gene-lifestyle interaction with disease traits. However, not all cohorts have data on all lifestyle factors, leading to increased heterogeneity in the environmental exposure in collaborative meta-analyses. We compared and evaluated four approaches (Naïve, Safe, Complete and Moderator Approaches) to handle the missingness in LRS-stratified meta-analyses under various scenarios. Compared to “benchmark” results with all lifestyle factors available for all cohorts, the Complete Approach, which included only cohorts with all lifestyle components, was underpowered due to lower sample size, and the Naïve Approach, which utilized all available data and ignored the missingness, was slightly inflated. The Safe Approach, which used all data in LRS-exposed group and only included cohorts with all lifestyle factors available in the LRS-unexposed group, and the Moderator Approach, which handled missingness via moderator meta-regression, were both slightly conservative and yielded almost identical p values. We also evaluated the performance of the Safe Approach under different scenarios. We observed that the larger the proportion of cohorts without missingness included, the more accurate the results compared to “benchmark” results. In conclusion, we generally recommend the Safe Approach, a straightforward and non-inflated approach, to handle heterogeneity among cohorts in the LRS based genome-wide interaction meta-analyses.Subject terms: Genetics, Risk factors 相似文献
994.
骨髓间质干细胞体外分化为成骨细胞的实验研究 总被引:13,自引:0,他引:13
建立猪骨髓间质干细胞 (mesenchymalstemcells ,MSCs)体外分离培养方法。对猪MSCs体外分化为成骨细胞的能力进行研究。抽取猪骨髓 ,体外培养MSCs。取第二代MSCs ,以含有不同浓度的抗坏血酸、β -磷酸甘油、地塞米松及碱性成纤维细胞生长因子等条件培养基进行成骨细胞诱导分化。通过细胞形态变化 ,碱性磷酸酶染色及钙盐沉积对成骨细胞进行鉴定。结果表明MSC细胞形态由长梭形向多边形转变 ,ALP染色阳性 ,VonKossa染色阳性 ,经体外诱导分化后呈典型的成骨细胞样改变。猪骨髓MSCs可在体外长期、稳定培养 ,具有向成骨细胞分化的潜能 ,可以为骨组织工程研究提供较理想的细胞来源和动物模型。 相似文献
995.
Molecular epidemiology of Vibrio cholerae O139 in China: polymorphism of ribotypes and CTX elements 总被引:5,自引:0,他引:5 下载免费PDF全文
Qu M Xu J Ding Y Wang R Liu P Kan B Qi G Liu Y Gao S 《Journal of clinical microbiology》2003,41(6):2306-2310
Vibrio cholerae O139, the second etiological serogroup of cholera, triggered the first outbreak of O139 cholera in China in 1993. To analyze the clone polymorphism of O139 isolates in China, 117 strains of V. cholerae O139, isolated from different areas in China between 1993 and 1999, were selected to characterize the phylogenetic relationships by molecular techniques. Analysis of restriction fragment length polymorphism in the conserved 16S rRNA gene revealed seven different ribotypes within the 117 strains. Among these strains, there were eight that lacked the cholera toxin gene (ctxAB), zot, and the repetitive sequence (RS); these eight strains belonged to three individual ribotypes. Our results suggested that V. cholerae O139 strains in China had clone diversity in phylogeny. The results of our hybridization patterns for CTX genetic elements (ctxAB, zot, and RS) showed that CTXPhi genomes in most V. cholerae O139 strains had two or more copies and had extensive restriction patterns even for the strains which belong to the same ribotype. For 22 (20.1%) strains, the copies of ctxAB were different from those of zot, suggesting that a ctxAB-negative CTXPhi genome may exist in O139 strains. This ctxAB-negative CTXPhi genome may coexist with the intact CTXPhi genome in a strain. In addition, the dendrogram for I-CeuI-generated pulsed-field gel electrophoresis patterns showed that V. cholerae serogroup O139 has a closer relationship with one strain of serogroup O22 than with the strains of serogroup O1. The results of this study showed the clonal diversity and the distribution of O139 strains in China, suggesting multiple origins of the O139 cholera epidemic or sporadic events. 相似文献
996.
目的探讨全髋关节置换术均衡双下肢长度的临床意义和手术设计。方法回顾分析2000-2004年获得随访的单侧全髋关节置换手术病例48例,采用骨水泥型假体12髋,混合型假体36髋,术前双下肢等长30例(含股骨颈骨折患者),10例患肢长度短缩1.0-2.0cm,6例短缩2.0-4.0cm,2例短缩4.0-6.0cm。通过术前肢体长度测量及X片测量制定手术方案,选择假体、预估颈长和截骨平面;术中正确磨削髋臼,寻找最佳旋转中心,结合透视及特殊试验修正截骨平面,调节假体颈长,达到均衡双下肢长度的目的。结果全部病例采用Harris评分,优30例,良12例,中4例,差2例。术前等长30例巾术后出现5例手术侧延长1.0-2.0cm,1例延长2.5cm。术前不等长的18例中,术后恢复等长10例,6例手术侧延长1.0-2.0cm,2例术前重度短缩的先天性髋关节发育不良病人术后仍然短缩2.0-3.0cm。术后肢体等长35例Harris评分平均92.3分,术后肢体不等长13例Harris评分平均88.6分。结论全髋关节置换术的手术设计。手术技巧以及假体设计等诸多因素影响下肢长度,术后肢体不等长降低了患者的满意度。应重视术前测量及术中综合评价方法的运用,重视软组织平衡技术和肢长调节,掌握全髋置换术中均衡下肢长度的手术技术,进一步改善手术效果。 相似文献
997.
腭部恶性肿瘤的CT诊断 总被引:6,自引:0,他引:6
探讨腭部恶性肿瘤的CT表现及其诊断价值。回顾性分析32例经病理证实的腭部恶性肿瘤的CT表现,其中男27例,女5例。所有病例均行横断增强扫描,其中8例同时行平扫,2例加冠状位扫描。腭部恶性肿瘤的CT表现为:(1)腭部肿块(26例)、腭部软组织增厚(6例)和腭骨质破坏(6例),其中病变位于软腭(22例)、硬腭(4例)、软硬腭交界处(3例);(2)邻近结构受累及(27例);(3)颈部淋巴结转移(17例)。CT是一种优良的检查技术,能显示腭部恶性肿瘤的大体病理改变以及侵犯途径,为临床治疗和预后提供重要信息。 相似文献
998.
目的:探讨个体化出院指导对高血压患者依从性的影响。方法:将80例患者随机分为实验组和对照组,分别给予个体化出院指导联合一般性出院指导和单用一般性出院指导,出院三个月和六个月时跟踪随访。结果:实验组的依从性明显好于对照组,出院后随访病情复发率明显降低(P〈0.05〉。结论:个体化出院指导可提高高血压患者依从性,改善患者的社会适应能力,降低复发率。 相似文献
999.
Bone marrow-derived mesenchymal stem cells in repair of the injured lung 总被引:26,自引:0,他引:26
Rojas M Xu J Woods CR Mora AL Spears W Roman J Brigham KL 《American journal of respiratory cell and molecular biology》2005,33(2):145-152
We sought to determine whether an intact bone marrow is essential to lung repair following bleomycin-induced lung injury in mice, and the mechanisms of any protective effects conferred by bone marrow-derived mesenchymal stem cell (BMDMSC) transfer. We found that myelosupression increased susceptibility to bleomycin injury and that BMDMSC transfer was protective. Protection was associated with the differentiation of engrafted BMDMSC into specific and distinct lung cell phenotypes, with an increase in circulating levels of G-CSF and GM-CSF (known for their ability to promote the mobilization of endogenous stem cells) and with a decrease in inflammatory cytokines. In vitro, cells from injured, but not from normal, mouse lung produced soluble factors that caused BMDMSC to proliferate and migrate toward the injured lung. We conclude that bone marrow stem cells are important in the repair of bleomycin-injured lung and that transfer of mesenchymal stem cells protects against the injury. BMDMSC localize to the injured lung and assume lung cell phenotypes, but protection from injury and fibrosis also involves suppression of inflammation and triggering production of reparative growth factors. 相似文献