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91.
The precise relationship between developmental dysplasia of the hip and dislocation among patients after total hip arthroplasty has not been well clarified. A total of 820 patients with developmental dysplasia of the hip who underwent total hip arthroplasty from January 2000 to December 2009 were categorized according to Crowe classification, and postoperative dislocation rates were analyzed among subgroups. The overall dislocation rate was 2.93%. No statistically significant differences in dislocation rates were observed between these with and without subtrochanteric osteotomy. Femoral head size was the only factor with significant difference between the dislocated and stable groups, especially when femoral head diameter increased from 28 to 32 mm. Of all dislocations, 69.6% were anterior dislocation, and the degree of cup anteversion and combined anteversion of anterior dislocators was higher than that of the posterior dislocators (P = .0082 and P = .001).  相似文献   
92.
We investigated the median nerve deformation in the carpal tunnel in patients with carpal tunnel syndrome and controls during thumb, index finger, middle finger, and a four finger motion, using ultrasound. Both wrists of 29 asymptomatic volunteers and 29 patients with idiopathic carpal tunnel syndrome were evaluated by ultrasound. Cross‐sectional images during motion from full extension to flexion were recorded. Median nerve cross‐sectional area, perimeter, aspect ratio of the minimal enclosing rectangle, and circularity in extension and flexion positions were calculated. Additionally, a deformation index was calculated. We also calculated the intra‐rater reliability. In both controls and patients, the median nerve cross‐sectional area became significantly smaller from extension to flexion in all finger motions (p < 0.05). In flexion and extension, regardless of the specific finger motion, the median nerve deformation, circularity and the change in perimeter were all significantly greater in CTS patients than in controls (p < 0.05). We found excellent intra‐rater reliability for all measurements (ICC > 0.84). With this study we have shown that it is possible to assess the deformation of the median nerve in carpal tunnel syndrome with ultrasonography and that there is more deformation of the median nerve in carpal tunnel syndrome patients during active finger motion. These parameters might be useful in the evaluation of kinematics within the carpal tunnel, and in furthering our understanding of the biomechanics of carpal tunnel syndrome in the future. © 2011 Orthopaedic Research Society. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:643–648, 2012  相似文献   
93.
目的 研究缩短中医拔罐致罐斑存留时间的有效方法.方法 选择正常健康成人30名,采用自身对照研究,在背部左边夹脊穴(第4~6胸椎旁)3个部位拔罐,分别设为A、B、C组.A组拔罐后对罐斑不作任何处理,B、C组拔罐后罐斑涂搽喜疗妥软膏,B组1次/d,C组2次/d,直至罐斑消失.结果 三组罐斑评分在拔罐后24 h及其下降幅度、罐斑消退时间比较,差异有统计学意义,C组最佳,B组次之,A组最差(均P<0.01).结论 喜疗妥能加速罐斑消褪,且每日2次优于每日1次用法.  相似文献   
94.
目的 探讨全腹腔镜下保胆取石一期缝合术(LRCL)的手术方法和适应证.方法 回顾性分析2002年3月至2011年11月开展LRCL 402例患者的临床资料.结果 施行LRCL 402例胆囊结石患者,成功373例(92.8%),中转腹腔镜胆囊切除术24例,出现并发症5例.无中转开腹,无继发胆总管结石,无死亡.手术时间30~160 min,平均约68 min.术后住院3~11 d.术后并发症率发生较低的缝合引流方法为:采用胆囊颈部切口和间断8字缝合,与非胆囊颈部切口和间断缝合、连续扣锁缝合相比具有统计学意义,P<0.01.术后1、3、5 年的复发率为1.1%、2.4%和4.0%.结论 对于合适的病例,LRCL保持了胆囊的功能,具有安全、术后住院时间短、并发症少、康复快、结石复发率低等优点,具有良好的应用前景.  相似文献   
95.
This paper is concerned with the optimal guaranteed cost stabilizing controller design problem for a class of networked control systems (NCSs) with random packet losses. The number of consecutive packet losses is assumed to be upper bounded, and the closed‐loop NCS is described as a discrete‐time stochastic delay system with a time‐varying input delay and a stochastic parameter. A sufficient condition is derived for the closed‐loop NCS to be exponentially stable and achieve an optimal guaranteed cost performance level. The relationships among the exponential decay rate, the guaranteed cost performance level, and two parameters characterizing the random packet losses, namely, the packet loss probability and the maximal number of consecutive packet losses, are simultaneously established in the obtained condition. Furthermore, design procedures for the state feedback stabilizing controllers are also presented. Finally, an illustrative example is given to show the effectiveness of the proposed results. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
96.
ObjectivesTo study the underlying alteration in the expression of epithelial markers involved in epithelial-mesenchymal transition (EMT), and elucidate the potential mechanism(s) for Tβ4-induced EMT-like phenotypic changes in bladder cancer cells.Materials and methodsAll tissue samples in this study were obtained from clinical patients of the Union Hospital of Tongji Medical College, and were confirmed by surgery and pathology. Of these, normal bladder tissues (control), primary urothelial carcinoma of different grades (Stage pTa, Stage pT3), bladder paracancerous tissues, accompanied with 2 bladder cancer cell lines (BIU-87 and T24), were divided into 6 groups. Quantitative RT-PCR, Western blotting, and immunohistochemical study of adhesion molecules Tβ4, ILK, E-cadherin, and β-catenin involved in EMT were carried out. A lentiviral gene transferring vector containing the RNA polymerase III-dependent U6 promoter to express short hairpin RNA (shRNA) directed against Tβ4 was also applied. In the present study, all agents were evaluated using commercial kits.ResultsA strong correlation between the expression levels of Tβ4, ILK, E-cadherin, and β-catenin was found in the bladder transitional cell carcinoma (TCC) patients. In the BIU-87 and T24 bladder cancer cells overexpressing Tβ4, which were accompanied by a loss of E-cadherin as well as a cytosolic accumulation of β-catenin, up-regulation of ILK was also revealed. The inhibition of the Tβ4 expression with lentiviral shRNA vector could raise EMT-like phenotypic changes, significantly depressed motility, and subsequent invasiveness of bladder cancer cells.ConclusionsOur results imply that the Tβ4 is likely to play a crucial role in EMT progression, and that inhibition of the Tβ4 expression or interactions with other genes should be novel therapeutic targets for bladder cancers with high invasive and metastatic potential.  相似文献   
97.
针对医学数字资源构建长期保存标准体系,结合研究现状,设计体系框架,为具有长期保存价值的医学数字资源提供保存标准,以期指导后续保存系统应用实践。  相似文献   
98.
设计与实现医学大数据长期保存系统(MedPRES),综合利用工作流、数字仓储、微服务以及云存储等关键技术保证医学数据的真实性、完整性、可获得性以及长期可解释性。医学大数据长期保存系统支持PB级数据的长期保存服务,提供从数据采集、接收、摄入到保存管理、审计以及服务的一整套解决方案,为重要医学数据的长期保存与利用提供有力保障。  相似文献   
99.
100.
目的:采用免疫组织化学的方法研究慢性肝损伤时肝干细胞在肝脏内的分布和增值,初步探讨肝脏的损伤修复与肿瘤发生的细胞生物学机制。方法:3,-me-DAB喂食大鼠四周,建立应激模型刺激大鼠肝内干细胞的迅速增殖,取材、固定制成石蜡切片,ABC法检测肝干细胞特异性的表面标记蛋白CD34、C-11、CK19、OV6和神经前体细胞的特异性表面标记Nestin在大鼠肝脏内的表达。结果:大鼠肝实质结构改变显著,汇管区内结缔组织细胞大量增生,浸润周围肝组织形成假小叶。靠近界板处断续的排列着卵圆样细胞分别表达CD34、CK19、OV6和Nestin,阳性细胞的形态和分布特点相似,而且具有典型的干细胞的特点。此外,肝实质内可见大量的单个核样干细胞分别表达OV6、CD34、Nestin和CK19。这些细胞类似造血系统来源的单核细胞分布在肝索、肝血窦、肝内血管、增生的小叶间胆管和胆管之间,多见于汇管区的结缔组织内。结论:3’-me-DAB作用后,肝内存在着多种干细胞,而且具有空间分布的规律性。增生的干细胞在损伤应激下继续增殖分化为肝实质细胞,参与肝脏的组织修复,同时成为引发肝脏肿瘤的可能原因之一,具体机制还需要进一步的深入研究。  相似文献   
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