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11.
Although an inverse relationship between body mass index (BMI) and baroreflex sensitivity (BRS) was found, the effect of waist circumference (WC) on BRS is still inconclusive. The contradictory results of previous studies may be related to the heterogeneity and relatively small sample size of the subjects examined. The aim of this population-based study was to investigate whether the influence of increased WC is more detrimental to BRS than BMI. A total of 760 community dwellers were recruited and they were classified into Q1 (n = 189), Q2 (n = 183), Q3 (n = 192) and Q4 (n = 196) groups, based on WC quartiles. Spontaneous BRS was determined by spectral α coefficient method. Valsalva ratio was the longest RR interval after release of Valsalva maneuver divided by the shortest RR interval during maneuver. Cardiac autonomic function was calculated by power spectrum of heart rate in low and high frequency (LF, 0.04–0.15 Hz; HF, 0.15–0.40 Hz), and LF/HF ratio in supine position for five minutes. There were significant differences in spontaneous BRS and Valsalva ratio among different WC groups. In multivariate analysis, obesity was inversely associated with spontaneous BRS and Valsalva ratio. However, these inverse relationships became insignificant after further adjustment for WC quartiles. In contrast, Q4 vs. Q1, Q3 vs. Q1 and Q2 vs. Q1 of WC were inversely related to spontaneous BRS. Q4 vs. Q1 and Q3 vs. Q1 of WC were negatively associated with the Valsalva ratio. In conclusion, increased and even high-normal WC had a stronger adverse effect on BRS than BMI, independent of cardio-metabolic risk factors.  相似文献   
12.

Background

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

Objective

To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5?μm (PM2.5) and the risk of metabolic syndrome in Korean adults without CVD.

Methods

Exposure to PM2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.

Results

Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m3 increase in PM2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).

Conclusion

Exposure to one-year average PM2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM2.5 affects the onset of MS and its components which may lead to increase the risk of CVD.  相似文献   
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ABSTRACT

In clinical trials, selection of appropriate study endpoints is critical for an accurate and reliable evaluation of safety and effectiveness of a test treatment under investigation. In practice, however, there are usually multiple endpoints available for measurement of disease status and/or therapeutic effect of the test treatment under study. For example, in cancer clinical trials, overall survival, response rate, and/or time to disease progression are usually considered as primary clinical endpoints for evaluation of safety and effectiveness of the test treatment under investigation. Once the study endpoints have been selected, sample size required for achieving a desired power is then determined. It, however, should be noted that different study endpoints may result in different sample sizes. In practice, it is usually not clear which study endpoint can best inform the disease status and measure the treatment effect. Moreover, different study endpoints may not translate one another although they may be highly correlated one another. In this article, we intend to develop an innovative endpoint namely therapeutic index based on a utility function to combine and utilize information collected from all study endpoints. Statistical properties and performances of the proposed therapeutic index are evaluated theoretically. A numerical example concerning a cancer clinical trial is given to illustrate the use of the proposed therapeutic index.  相似文献   
15.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
16.
目的:构建基于SERVQUAL模型的医养结合型养老机构卫生服务质量评价指标体系。方法:围绕医养结合型养老机构卫生服务的概念、特性、内涵、内容等,采用文献研究法、半结构式访谈法、Delphi—AHP法等定性与定量相结合的研究方法,构建指标体系并确定指标权重。结果:构建了具有7个一级指标,27个二级指标和77个三级指标的养老机构卫生服务质量评价指标体系。指标体系三轮咨询专家权威系数Cr均高于0.84,专家综合权威性系数均高于0.83;总体专家协调系数Kendall W第一、二轮为0.309,第三轮为0.706,且均通过显著性检验;内容效度指数I-CVI介于0.90~1.00之间,S-CVI为0.94,kappa值均高于0.74;信度系数Cronbachα总体为0.972,各维度Cronbachα系数在0.792~0.921之间。评价指标体系具有较好的稳定性、可靠性和一致性。结论:本研究建立的评价指标体系有利于医养结合型养老机构全面建立贴近老年人卫生服务需求的内设医疗机构,改善机构内卫生服务质量。在对指标体系进行应用时,可转化为机构中老年人对各指标项目的感受(P)与期望(E),以两者的差值(P-E)代表机构的卫生服务质量。根据专家赋权结果,应重点加强医养结合养老机构对可靠性、有效性、经济性等指标项目的建设。  相似文献   
17.
ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.  相似文献   
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近10年来,甲状腺外科快速发展。随着甲状腺外科相关指南、专家共识的不断修订与完善,在专业团体的引导下,中国甲状腺外科在术前诊断、手术方式、治疗方法创新等方面实现了可喜发展,病人5年生存率明显提高。甲状腺疾病诊治技术快速革新、外科术式的发展与统一、多学科诊疗模式发展与应用、术后规范化管理助力疗效提高、重视特殊情况下的甲状腺癌及髓样癌诊治以及质量控制体系的建立与完善等综合发展提升了甲状腺癌诊疗的安全性、精准性,有效的改善了病人生活质量、延长生存时间,为建设健康中国贡献力量。  相似文献   
20.
《中国现代医生》2020,58(4):84-86+90
目的评价西药联合穴位贴敷中西医结合治疗复治肺结核的临床疗效。方法选择本院2017年1月~2018年1月收治的60例复治肺结核患者进行分组研究,全部患者根据治疗方法不同随机分为两组,每组各30例。两组均采取西药进行治疗,采用2HRZE/6HRZ标准化疗方案,实验组同时联合穴位贴敷中西医结合进行治疗,治疗后对比分析两组病灶吸收情况及两组临床症状改善情况。结果实验组病灶恶化9例,其病灶显著吸收率达50.0%,总有效率达70.0%,对照组病灶恶化6例,不变5例,其病灶显著吸收率达33.3%,总有效率达63.3%,两组病灶吸收总有效率组间比较,差异具有显著性(P0.05);实验组的疗效指数治疗6个月后显著高于对照组,组间比较,差异具有显著性(P0.05)。结论西药联合穴位贴敷中西医结合治疗复治肺结核疗效确切,可以显著促进病灶吸收,改善临床症状,安全性好,且还可以扶助人体正气,提高机体免疫力,调节全身状态,以达到治疗目的,是治疗复治肺结核的有效方法之一,值得临床广泛推广和应用。  相似文献   
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