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Matthew J. McQueen Peter A. Kavsak Liqin Xu Olga Shestakovska Salim Yusuf 《Clinical biochemistry》2013,46(1-2):5-9
ObjectivesPrevious work on high-sensitivity troponin I (hs-cTnI) has demonstrated that it may identify patients with stable cardiovascular disease (CVD) at risk for future myocardial infarction (MI). In this study, we assessed if hs-cTnT concentrations could also identify those stable CVD patients at high risk for future MI and other ischemic cardiac outcomes.Methodshs-cTnT (lot:153-401) was measured in specimens obtained at randomisation in the Heart Outcomes Prevention Evaluation (HOPE) study (n = 2941 stable CVD patients, 4.5 years follow-up). The primary outcome for the HOPE study (MI, stroke, or cardiovascular death) was used to identify cutoffs by receiver operating characteristic (ROC) curve analysis and was used in conjunction with the 95th and 99th percentile upper limits to construct different concentration ranges, which were assessed using log-rank tests and multivariable Cox proportional hazard models. These different concentration ranges were then assessed for the components of the primary outcome and for heart failure (HF).ResultsThe ROC derived hs-cTnT cutoff was 8 ng/L for the primary outcome. Subjects with hs-cTnT either below (8 to < 14 ng/L) or slightly above the published 99th from a healthy population (14 to 21 ng/L) had similar probability for the primary outcome. Those with hs-cTnT concentrations > 31 ng/L had the highest probability and greatest risk for future MI, HF, and cardiovascular death as compared to those with hs-cTnT concentrations < 8 ng/L.ConclusionIn patients with stable CVD disease hs-cTnT measurement identifies those at risk for MI as well as HF and cardiovascular death. 相似文献
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目的 近年来,医学、外科类文献有向循证医学方向发展的趋势.本研究旨在检测已发表的整形外科类文章的证据水平.方法 回顾性分析<整形再造外科杂志(Plastic and Reconstructive Surgery,PRS)><整形外科年鉴(Annals of Plastic Surgery,Annals)><整形再造与美容外科杂志(Journal of Plastic,Reconstructive,and Aesthetic Surgery,JPRAS)><美国美容外科杂志(American Journal of Aesthetic Surgery,Aesthetic)>4本主要的整形外科类杂志2009年1~12月刊载论文利用证据的水平.结果 在1759篇文献中,共有726篇(41%)纳入本研究标准(排除动物实验、尸体研究、基础医学、文献复习、继续教育和信函等方面文献).将选中的文献根据其证据水平进行分级(Ⅰ~Ⅳ级;Ⅰ级,证据水平最高,如随机对照研究;Ⅳ级,证据水平最低,如病例报告).4本杂志的平均证据水平分别为:PRS=3.05,Aesthetic=3.11,JPRAS=3.35,Annals=3.31.4本杂志的平均证据水平,除了JPRAS与Aesthetic的差异无统计学意义外,余者差异均有统计学意义(P<0.05).本研究纳入标准的文献,只有2.2%的证据水平为Ⅰ级.结论 4本杂志的平均证据水平为3.2(Ⅲ级水平).为了使整形外科专业加入到高水平循证医学行列,我们应当在今后的工作中着重强调随机对照研究的应用. 相似文献
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Engin Dursun Salim Dogru Atila Gungor Hakan Cincik Ethem Poyrazoglu Taner Ozdemir 《Otolaryngology--head and neck surgery》2008,138(3):353-356
OBJECTIVE: To compare the effectiveness of paper-patch, fat, and perichondrium myringoplasty in the treatment of chronic tympanic membrane perforations smaller than 3 mm. SUBJECTS AND METHODS: This investigation included 45 patients with chronic tympanic membrane perforations smaller than 3 mm. The patients were equally divided into 3 main groups according to surgical procedures. Each group consisted of 3 subgroups, which had 1-mm, 2-mm, and 3-mm perforations. The patients underwent paper-patch, fat, or perichondrium myringoplasty via transcanal approach under local anesthesia. Healing of perforation, hearing improvement, and complications were investigated. RESULTS: Closure rates of the perforations in the paper-patch, fat, and perichondrium myringoplasty groups were 66.7%, 86.7%, and 86.7%, respectively. There were no statistically significant differences in tympanic membrane closure rates between techniques with regard to size. CONCLUSION: Three techniques were found to be feasible for tympanic membrane perforations smaller than 3 mm. 相似文献
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Christian P. DiPaola MD Justin A. Jacobson MD Hani Awad PhD Bryan P. Conrad MSEng Glenn R. Rechtine II MD 《The spine journal》2008,8(5):717-722
BACKGROUND CONTEXT: Two common justifications for orienting cervical screws in an angled direction are to increase pullout strength and to allow use of longer screws. This concept is widely taught and has guided implant design. Fixed- versus variable-angle systems may offer strength advantages. Despite these teachings, there is a paucity of supporting biomechanical evidence. The purpose of our study is to test the influence of screw orientation and plate design on the maximum screw pullout force. PURPOSE: This study evaluates the effect of screw orientation and plate type (fixed- vs. variable-angle) on screw pullout strength. STUDY DESIGN: Anterior cervical plates of both a fixed- and variable-angle CSLP, were tested for peak pullout strength in a direct plate pullout model using polyurethane foam bone, which models osteoporotic bone. METHODS: Self-tapping, locking screws (4.0x14mm and 4.0x16mm) were used. Screws were oriented in the fixed-angle plate in the standard fashion. In the variable plate, screws were instrumented in three different orientations. Biomechanical testing was performed on an Instron DynaMight 8841 servohydraulic testing machine, measuring maximum pullout force under a displacement-controlled pullout rate of 1mm/min. Five samples were tested per group. RESULTS: When all screws were placed 90 degrees to the plate, there was a significantly increased peak pullout strength (412.8+/-22.2N) compared with when all screws were placed 12 degrees "up and in" (376.2+/-24.3N, p less than or equal to .03). When the 90 degrees construct was reproduced using 14-mm screws and compared with 16-mm screws oriented 12 degrees "all up and in," there was still significantly higher pullout strength with the all 90 degrees construct (434.2+/-28.7N vs. 376.2+/-24.3N, p less than or equal to .009). The fixed-angle plate had a significantly decreased peak pullout strength (288.2+/-15.7N) compared with the variable-angle plate (416.6+/-12.6N) (p less than .00001) when the screws were placed in the same orientation. Overall, the variable-angle plate, regardless of the orientation of screws, had a significantly greater pullout strength than the fixed-angle plate (p less than .001). CONCLUSIONS: In this system, a variable-angle plate has greater pullout strength than a fixed-angle plate, regardless of the orientation of screws. With the variable-angle plate, a construct of all screws 12 degrees "up and in" is the weakest configuration. We found that with the 90 degrees construct, both 16- and 14-mm screws performed significantly better than 16-mm convergent screws. These findings are remarkable because they contradict the current doctrine. This may be a function of plate-dependent factors and should not be applied universally to all plate systems. Further study of screw orientation in additional plating systems is warranted. 相似文献
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Innocenti GR Wadei HM Prieto M Dean PG Ramos EJ Textor S Khamash H Larson TS Cosio F Kosberg K Fix L Bauer C Stegall MD 《Transplantation》2007,83(2):144-149
BACKGROUND: Preemptive kidney transplantation (prior to the institution of dialysis) avoids the morbidity and mortality of dialysis; however, detailed studies of high-risk patients are lacking. The aim of the current study was to compare recent outcomes of preemptive (P) versus nonpreemptive (NP) living donor kidney transplantation with an emphasis on high-risk recipients. METHODS: We retrospectively analyzed 438 sequential solitary living donor kidney transplants at our institution between January 2000 and December 2002. In all, 44% were preemptive. NP recipients were dialyzed for 21+/-36 months (range 1-312 months). RESULTS: Overall, three-year patient survival was similar in the NP and P groups. When stratified by diabetes and age >65 years, P and NP recipients again showed similar survival. Death-censored three-year graft survival was better in the P group (97% vs. 90%, P=0.01), but was not significant by multivariate analysis. Delayed graft function was more frequent in NP vs. P (10% vs. 4%; P=0.01), but other early complications were similar including: acute rejection, 16% vs. 11% (P=0.11); primary nonfunction, 3% vs. 2% (P=0.38); and wound complications, 19% vs. 17% (P=0.54). Glomerular filtration rate at three years was similar in the two groups (53+/-23 preemptive vs. 52+/-20 ml/min nonpreemptive; P=0.37). CONCLUSION: With prompt referral and workup, preemptive kidney transplantation can be performed successfully in a large percentage of renal allograft recipients. Preemptive transplantation avoids unnecessary dialysis and should be emphasized as initial therapy for many patients with end-stage renal disease. 相似文献
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Cengiz Candan Nur Canpolat Selman Gökalp Nurdan Yıldız Pınar Turhan Mehmet Taşdemir Lale Sever Salim Çalışkan 《Pediatric nephrology (Berlin, Germany)》2014,29(1):95-102