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71.
Anna C. Rienmüller Sandro M. Krieg Franziska A. Schmidt Elias L. Meyer Bernhard Meyer 《The spine journal》2019,19(1):113-120
Background Context
The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).Purpose
The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.Design
We carried out a post hoc analysis of a prospectively collected database in a level I spine center.Patients Example
The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.Outcome Measures
Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.Methods
We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.Results
The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.Conclusions
Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection. 相似文献72.
《Drug metabolism and pharmacokinetics》2019,34(1):87-94
The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with Ki values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with Km values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CLR) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CLR (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CLR of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates. 相似文献
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目的了解上海市黄浦区社会办医疗美容机构的管理人员和医师对《医疗美容管理办法》相关内容的掌握情况,发现存在的问题并提出改善建议.方法采用现场调查与现场问卷调查相结合的方式,对在上海市黄浦区开展医疗美容科目的所有社会办医疗机构(共计38家)进行全覆盖现场调查,并对其中的管理人员41人、相关医师31人进行问卷调查.结果38家社会办医疗美容机构中,美容外科和美容皮肤科的开展率较高,分别为96.8%和97.2%,而美容牙科开展率为52.4%,美容中医科开展率最低(25.0%).管理人员关于非主诊医师可在主诊医师指导下工作的知晓率仅68.3%.关于美容外科、皮肤科、中医科、牙科主诊医师应具备的工作年限,管理人员答对率为90.2%,医师答对率为72.0%,二者有显著性差异(P<0.05).结论社会办医疗美容机构中的二级科目设置需进一步优化,以减少资源空置.应加强对医疗机构管理人员和医师的法律培训,改变经营模式,制定明确的准入与退出机制,从而减少违法违规行为的发生. 相似文献
75.
目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)对三阴性乳腺癌的临床预后影响及与Ki - 67表达的关系。方法 回顾性分析2006年1月 - 2012年12月于我院乳腺外科住院治疗的134例三阴性乳腺癌患者。NLR最佳临床分界值采用ROC曲线确定,并依此分NLR<2.64组和NLR≥2.64组。临床独立预后因素采用单因素和多因素Cox回归模型分析。术后生存时间和生存曲线比较采用Kaplan - Meier和log - rank方法。Ki - 67的表达采用免疫组织化学方法检测。结果 NLR是三阴性乳腺癌的独立预后因素,最佳临界值为2.64。NLR<2.64组术后中位DFS为39.10月,中位OS为52.30月;NLR≥2.64组术后中位DFS为27.35月,中位OS为37.35月。2组术后DFS和OS比较,差异具有统计学意义(P<0.05)。NLR低组伴Ki - 67表达阴性的三阴性患者术后中位DFS和OS生存时间显著高于其他情况。结论 NLR是三阴性乳腺癌的关键影响预后因素,具有重复性强、非侵袭性、方便实用等特性,可用于预测三阴性乳腺癌临床预后。 相似文献
76.
目的 分析重症医学科PBL教学法在临床心肺复苏术教学中的应用效果.方法 本次实验的开展基础数据选择2016年9月—2018年7月进入医院重症医学科实习学生64例,按照学生自身意愿以及学校安排将参与实验学生分为均数相同的两个小组(对照组、观察组),每组实验人数均为32例,其中对照组(n=32)采用传统教学方法 ,观察组(n=32)则应用PBL教学法教学,对比两组学生在学期结束后整体的学习质量情况和教学满意率.结果 观察组学生经过测试后理论知识和专业技能得分均对比对照组更高,教学效果更加理想,观察组学生对于教学的满意率评价更高,P<0.05.结论 重症医学科临床心肺复苏术教学中应用PBL教学法,将理论与实践进行结合,对教学方法 进行改进,全面提升学生的思维理解能力,培养良好的动手能力,促进理论教学与实践的结合,为学生以后的职业生涯提供更加理想的条件. 相似文献
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ObjectiveProgrammed death ligand 1 (PD-L1) has been reported to be connected to prognosis in individuals with malignant pleural mesothelioma (MPM), although there is no consensus based on data from previous studies. Accordingly, this quantitative meta-analysis investigated prognostic and clinicopathological utility of PD-L1 in patients with MPM.MethodsA comprehensive search of the PubMed, Web of Science, Embase, and Cochrane Library databases for articles published up to October 4, 2019 was performed. Studies using immunohistochemical techniques to detect/quantify the expression of PD-L1 in MPM tissue were enrolled in the analysis. The combined hazard ratio (HR) and corresponding 95% confidence interval (CI) was applied to assess the association between PD-L1 expression and overall survival (OS).ResultsA total of 11 studies comprising 1606 patients was included in the present meta-analysis. For OS, pooled data revealed an HR of 1.50 (95% CI 1.32–1.70; p < 0.001), suggesting that patients with PD-L1 overexpression experience inferior OS. Subgroup analysis revealed that elevated PD-L1 remained a significant prognostic indicator for worse OS, irrespective of sample size, cut-off value, ethnicity, and Newcastle-Ottawa Scale score. Moreover, PD-L1 overexpression was associated with non-epithelioid histology (odds ratio 4.30 [95% CI 1.89–9.74]; p < 0.001).ConclusionsResults of this meta-analysis show that elevated expression of PD-L1 could be a factor predicting poorer survival in patients with MPM. 相似文献
80.
目的:探讨醛-酮还原酶家族7成员A3(AKR7A3)在肺腺癌中的异常表达及与临床病理特征的关系,并探究其临床意义。方法:采用生物信息学数据库分析、免疫组化、Western Blot、Real-time PCR等方法对肺腺癌组织及不同细胞中AKR7A3的表达进行检测与分析。结果:Oncomine数据库分析结果显示,在肺腺癌中,AKR7A3的表达普遍高于正常肺组织,分别为正常肺组织的1.811倍(P=0.022)、1.356倍(P<0.01)、1.413倍(P=0.002)。Kaplan-Meier Plotter数据库分析结果显示,AKR7A3高表达的患者较低表达的患者生存时间缩短,差异具有统计学意义(P=0.003 7)。免疫组化染色显示肺腺癌组织中AKR7A3的表达较癌旁增高,在与临床病理特征的相关性分析中,发现其与肿瘤分化程度(P<0.01)、淋巴结转移情况(P=0.029)以及TNM分期(P<0.01)相关,且会造成患者生存时间缩短(P=0.031)。Cox多因素分析表明AKR7A3可能是影响肺腺癌患者预后的独立危险因素(P=0.012)。Western Blot及Real-time PCR实验提示不同肺腺癌细胞中AKR7A3蛋白及mRNA表达普遍增高。结论:AKR7A3在肺腺癌中表达增高,对预后有不良影响,有促进肿瘤发生发展的作用。 相似文献