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Harry S. Hothi Ashley K. MatthiesReshid Berber BSc MBBS MRCS Robert K. WhittakerJohn A. Skinner MBBS FRCS FRCS Alister J. Hart MA MD FRCS 《The Journal of arthroplasty》2014
It has been suggested that corrosion and fretting at the tapered, modular junctions of hip arthroplasties may contribute to implant failure. In this study the reliability of a commonly used peer-reviewed scoring system for visual assessment of corrosion and fretting at these junctions was evaluated. Volumetric material loss at the tapered head surface was measured and associations with the visual scores were investigated. We found that the inter-observer reproducibility and single-observer repeatability of the corrosion scores were substantial using Cohen’s weighted Kappa statistic (k = 0.64–0.71). The reproducibility and repeatability of the fretting scores however were slight to fair (k = 0.18–0.31). Taper corrosion scores were significantly and moderately correlated with the volume of material loss measured (Spearman’s r = 0.59; P < 0.001). We recommend the continued use of this scoring system but it should not be a substitute for measurement of material loss. 相似文献
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骨质疏松是一种常见疾病,骨质疏松的病因学和发病机制至今还没有被阐明清楚,目前还没有彻底治疗骨质疏松的方法,但是研究疾病的发病机制可以为骨质疏松患者提供全新的治疗方法。最近的研究表明了辅助T细胞( Th)在骨量丢失(一种系统性的炎症反应)发病机制中可能存在作用。然而,在一些已经发表的文章中,Th1/Th2细胞在调节破骨细胞的功能上存在着争议,这一争议被新近发现的Th17细胞所解决。 Th17是一种新亚型的T细胞,可以选择性的分泌不同的促炎因子,刺激破骨细胞分裂,已经被证实在炎症动物模型中可以加速骨量的丢失。因此Th17细胞会是未来治疗骨质疏松的目标靶点。 相似文献
86.
肝脏神经内分泌癌1例 总被引:1,自引:0,他引:1
神经内分泌癌又称类癌,多见于胃肠道,支气管等部位,很少见于肝脏,本文报告1例经病理证实的肝脏神经内分泌癌,旨在探讨其景仰学和组织学特点。 相似文献
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随着生命科学的快速发展,分子生物学在传染病诊断和治疗研究中的作用日益重要。本文针对传染病专科医院分子生物学实验教学特点,以问题为导向的教学方法(PBL)为核心,从更新教学内容、改进教学方法、丰富教学手段及培养科学思维等方面阐述了研究生细胞生物学实验教学改革的实践及体会。 相似文献
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背景:表皮干细胞对于修复皮肤缺损具有重要意义,但如何方便、快捷地对所获取的表皮干细胞进行纯化培养一直没有比较好的技术方法。目的:拟应用胰蛋白酶差速脱壁法去除表皮干细胞中混杂的成纤维细胞。设计、时间及地点:细胞学体外观察,于2006-06/2007—06在解放军军事医学科学院输血医学研究所干细胞与再生医学研究室完成。材料:实验所用皮肤来源于20~30岁女性乳房缩小整形术患者,由北京协和医院整形外科提供。方法:无菌条件下切取皮肤,剪除皮下脂肪组织,采用胶原酶/Dispase酶和胰蛋白酶两步法体外分离培养表皮干细胞。待细胞生长达70%~80%融合时,加入胰蛋白酶消化尚未脱壁的细胞,30s~1min后吸出脱壁细胞,同法传代培养至第5代细胞。主要观察指标:第1,5代表皮干细胞表面标志CD29、CD49f、CD71的表达。流式细胞仪检测第5代细胞生长周期。免疫荧光检测第5代表皮干细胞和传代时胰蛋白酶消化30s~1min即脱壁细胞角蛋白19及波形蛋白的表达。透射电镜观察表皮干细胞超微结构。结果:第1代表皮干细胞CD29阳性率94.32%,CD49f阳性率86.24%,CD71呈弱阳性,经过4次胰蛋白酶差速脱壁去除混杂细胞后,第5代表皮干细胞CD29阳性率96.77%,CD49f阳性率96131,CD71呈弱阳性,82.58%表皮干细胞处于G0~G1期。第5代表皮干细胞角蛋白19呈阳性,波形蛋白呈阴性,而传代时胰蛋白酶消化脱壁的细胞角蛋白19呈阴性,波形蛋白呈阳性,证实为成纤维细胞。表皮干细胞呈克隆样生长,透射电镜下胞质中可见呈束状排列的角蛋白丝。结论:应用胰蛋白酶差速脱壁法能够简单、有效地获取纯化的表皮干细胞。 相似文献
89.
E. John Gallagher MD Gary Lombardi MD Paul Gennis MD Marsha Treiber MA 《Academic emergency medicine》1994,1(5):423-429
Objective: To identify variation in outcome predictor documentation in out-of-hospital cardiac arrest associated with two different methods of data collection: concurrent questioning of personnel following a resuscitation attempt and archival report review.
Methods: All patients ≤ 18 years old who had had out-of-hospital cardiac arrests, verified using the New York City 911 telephone system, between October 1, 1990, and April 1, 1991, were eligible for inclusion. The authors reviewed the first 200 cases of presumed primary cardiac arrest involving a resuscitation attempt from among 3,243 consecutive ambulance call reports for cardiac arrest occurring during the study period. This archival data set was compared with data for the same 200 cases gathered through direct interview of field personnel by trained paramedics. The two data sets had been compiled independently by different individuals, using the same data collection instrument, which conformed to the Utstein template.
Results: Comparison of the data obtained from ambulance records with the data obtained from interviews of prehospital personnel revealed several areas of variance. Of note was a significantly lower proportion of bystander-witnessed ventricular fibrillation (VF) in the data set gathered from written reports (7% vs 18%; 95% CI for the difference 4–18%; p = 0.001).
Conclusion: Differences in methods of collection of out-of-hospital cardiac arrest data are associated with a more than twofold variation in the reported incidences of witnessed cardiac arrests manifesting as VF. Methodology-dependent variation in this important "denominator" may produce substantially different estimates of survival within the same cohort of patients. 相似文献
Methods: All patients ≤ 18 years old who had had out-of-hospital cardiac arrests, verified using the New York City 911 telephone system, between October 1, 1990, and April 1, 1991, were eligible for inclusion. The authors reviewed the first 200 cases of presumed primary cardiac arrest involving a resuscitation attempt from among 3,243 consecutive ambulance call reports for cardiac arrest occurring during the study period. This archival data set was compared with data for the same 200 cases gathered through direct interview of field personnel by trained paramedics. The two data sets had been compiled independently by different individuals, using the same data collection instrument, which conformed to the Utstein template.
Results: Comparison of the data obtained from ambulance records with the data obtained from interviews of prehospital personnel revealed several areas of variance. Of note was a significantly lower proportion of bystander-witnessed ventricular fibrillation (VF) in the data set gathered from written reports (7% vs 18%; 95% CI for the difference 4–18%; p = 0.001).
Conclusion: Differences in methods of collection of out-of-hospital cardiac arrest data are associated with a more than twofold variation in the reported incidences of witnessed cardiac arrests manifesting as VF. Methodology-dependent variation in this important "denominator" may produce substantially different estimates of survival within the same cohort of patients. 相似文献
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