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41.
Annamaria Guolo 《Statistics in medicine》2022,41(1):163-179
Control risk regression is a diffuse approach for meta-analysis about the effectiveness of a treatment, relating the measure of risk with which the outcome occurs in the treated group to that in the control group. The severity of illness is a source of between-study heterogeneity that can be difficult to measure. It can be approximated by the rate of events in the control group. Since the estimate is a surrogate for the underlying risk, it is prone to measurement error. Correction methods are necessary to provide reliable inference. This article illustrates the extent of measurement error effects under different scenarios, including departures from the classical normality assumption for the control risk distribution. The performance of different measurement error corrections is examined. Attention will be paid to likelihood-based structural methods assuming a distribution for the control risk measure and to functional methods avoiding the assumption, namely, a simulation-based method and two score function methods. Advantages and limits of the approaches are evaluated through simulation. In case of large heterogeneity, structural approaches are preferable to score methods, while score methods perform better for small heterogeneity and small sample size. The simulation-based approach has a satisfactory behavior whichever the examined scenario, with no convergence issues. The methods are applied to a meta-analysis about the association between diabetes and risk of Parkinson disease. The study intends to make researchers aware of the measurement error problem occurring in control risk regression and lead them to the use of appropriate correction techniques to prevent fallacious conclusions. 相似文献
42.
目的:探讨复杂骨盆骨折手术治疗中3D打印骨折模型的应用方法及效果。方法:选取医院收治的60例复杂骨盆骨折患者,按照随机数表法将其分为对照组和观察组,每组30例。对照组行传统CT指导下手术治疗,观察组行3D打印仿真骨盆模型体外模拟术后,应用腹直肌旁切口钢板内固定术治疗。比较两组手术时间、住院时间和骨折愈合时间,以及术中出血量、并发症发生率和骨盆功能恢复优良率。结果:观察组手术时间、住院时间及骨折愈合时间短于对照组,术中出血量少于对照组,差异有统计学意义(t=2.721,t=2.458,t=2.791,t=4.450;P<0.05);观察组和对照组并发症发生率分别为3.33%和10.00%,差异无统计学意义(x2=0.267,P>0.05);观察组和对照组骨盆功能恢复优良率分别为96.67%和73.33%,观察组明显高于对照组,差异有统计学意义(x2=4.705,P<0.05)。结论:复杂骨盆骨折手术中应用3D打印骨折模型可缩短手术时间、住院时间,减少出血量,促进骨折愈合,可改善骨盆功能且并发症少。 相似文献
43.
目的本研究分析舒巴坦治疗老年心力衰竭患者肺部感染的临床效果及不良反应发生情况,为临床治疗提供参考。方法160例老年心力衰竭肺部感染患者为研究对象,分为两组:对照组(n=80)患者在常规治疗的基础上采用头孢曲松钠治疗,观察组(n=80)患者在常规治疗的基础上采用头孢哌酮钠舒巴坦治疗。分析两组患者的细菌清除率、治疗前后心功能和肺功能的改善及不良反应的发生情况。结果观察组患者在细菌清除率明显高于对照组患者的细菌清除率(对照组vs观察组=84.35%vs 87.92%,χ2=5.654,P<0.05);两组患者治疗后心功参数LVEDD、LVESD、LVEF和肺功参数用力呼气容积和用力肺活量均得到显著的改善(P<0.05),且与对照组相比,观察组患者的上述指标改善显著(P<0.05);两组研究对象的不良反应包括凝血功能障碍、肝功能障碍、轻度皮疹和呕吐。结论舒巴坦治疗老年心力衰竭患者肺部感染安全性高,且临床疗效值得认可,可在临床推广应用。 相似文献
44.
《The Annals of thoracic surgery》2023,115(1):88-95
BackgroundRecent guidelines for the treatment of moderate or severe ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) have changed. This study assessed the real-world impact of changing guidelines on the management of IMR during CABG over time. We hypothesized that the utilization of mitral valve repair for IMR would decrease over time, whereas mitral valve replacement for severe IMR would increase.MethodsPatients undergoing CABG in a statewide collaborative database (2011-2020) were stratified by severity of IMR. Trends in mitral valve repair or replacement were evaluated. To account for differences of the patients, propensity score–matched analyses were used to compare patients with and without mitral intervention.ResultsA total of 11,676 patients met inclusion criteria, including 1355 (11.6%) with moderate IMR and 390 (3.3%) with severe IMR. The proportion of patients undergoing mitral intervention for moderate IMR decreased over time (2011, 17.7%; 2020, 7.5%; Ptrend = .001), whereas mitral replacement for severe IMR remained stable (2011, 11.1%; 2020, 13.3%; Ptrend = .14). Major morbidity was higher for patients with moderate IMR who underwent mitral intervention (29.1% vs 19.9%; P = .005). In a propensity analysis of 249 well-matched pairs, there was no difference in major morbidity (29.3% with mitral intervention vs 23.7% without; P = .16) or operative mortality (1.2% vs 2.4%; P = .5).ConclusionsConsistent with recent guideline updates, patients with moderate IMR were less likely to undergo mitral repair. However, the rate of replacement for severe IMR did not change. Mitral intervention during CABG did not increase operative mortality or morbidity. 相似文献
45.
淋巴管作为循环系统的重要组成部分之一,具有调节机体体液稳态,协助免疫监视和肠道脂质吸收等重要作用。淋巴管新生是机体生理和病理过程中维持脉管系统结构和功能正常的重要手段,淋巴管新生调控对于防治肿瘤、心血管等诸多疾病有着潜在的临床转化意义;淋巴回流功能则与关节炎症等疾病发病机制关系密切。在循环系统中,相较于中医药调控血管相关疾病的发病机制已取得很大进展,近年来对于淋巴管的研究则明显相对滞后。本文从中医药作用于淋巴管新生及回流功能角度对这一领域的研究进展作一综述,以期为临床上中医药治疗相关疾病提供新的思路与方法。 相似文献
46.
目的:应用磁共振成像(MRI)技术探究空气细颗粒物PM2.5暴露水平对健康成年人大脑灰质体积(GMV)和认知功能的影响。方法:选取487例健康成人,采集一般人口学信息及详细居住信息,并根据居住信息获取各受试近6个月和8岁~15岁期间的PM2.5暴露水平,对所有研究对象完成高分辨率结构MRI扫描,使用中文版精神分裂症认知功能成套测验-共识版(MCCB)进行认知测查,使用相关和回归分析探索空气PM2.5暴露水平与GMV和认知功能的关联。结果:近6个月PM2.5暴露水平与大脑右侧额下回三角部(brodmann分区[BA] 45)和右侧颞中回(BA 22)GMV存在负性关联(FWE校正,P<0.05,团块>10体素);与MCCB认知评估的信息处理速度-连线测试(r=-0.17,P<0.01)和推理和问题解决-迷宫测验评分(r=-0.22,P<0.01)负相关。8~15岁时的累积空气PM2.5暴露量与左侧梭状回(BA 18)和右侧舌回(BA 17)GMV负相关(FWE校正,P<0.05,团块>10体素),且与信息处理速度-连线测试、推理和问题解决-迷宫测验评分... 相似文献
47.
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49.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):149-158.e4
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization. 相似文献
50.