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61.
62.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable. 相似文献
63.
目的:探讨阿帕替尼单药在标准治疗方案失败晚期结直肠癌(colorectal cancer,CRC)患者中的疗效和安全性。方法:本研究为前瞻性研究设计,用PASS15 软件计算研究所需的样本量,从2017 年7 月到2018 年8 月入组标准方案治疗失败的晚期CRC患者52 例,给予阿帕替尼起始剂量750 mg或500 mg单药治疗;评估患者的客观缓解率(ORR)和疾病控制率(DCR),随访评价患者的无进展生存期(PFS)和总生存期(OS),并记录治疗过程中出现的不良反应。主要研究终点为PFS,次要研究终点为ORR、DCR、OS和安全性。结果:纳入研究的52 例CRC患者中45 例可以评价疗效及安全性,其均为既往接受过至少2 次系统性化疗的晚期CRC患者。疗效:完全缓解0 例、部分缓解5 例、疾病稳定30 例、疾病进展10 例,ORR为11.11%、DCR为77.78%;预后:45 例患者的中位PFS 为3.95 个月(95% CI=3.16~4.74),中位OS为10.3 个月(95% CI=5.70~14.90);3 级以上不良反应:手足综合征6 例(13.33%),高血压5 例(11.11%),蛋白尿5 例(6.67%),转氨酶升高4 例(8.89%),腹泻3 例(6.67%),疲劳2 例(4.44%),出血1例(2.22%)。结论:阿帕替尼单药治疗标准方案失败的晚期CRC患者具有潜在的临床获益,安全性事件总体可控。 相似文献
64.
《Obesity research & clinical practice》2020,14(2):158-163
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
65.
66.
Krishna S. Iyer 《Platelets》2020,31(4):474-482
Abstract Platelets are small, anucleated effector cells that play an important role in linking the hemostatic and inflammatory processes in the body. Platelet function is known to be altered under various inflammatory conditions including aging. A gain in platelet function during aging can increase the risk of thrombotic events, such as stroke and acute myocardial infarction. Anti-platelet therapy is designed to reduce risk of serious cerebrovascular and cardiovascular events, but the adverse consequences of therapy, such as risk for bleeding increases with aging as well. Age-associated comorbidities such as obesity, diabetes, and hyperlipidemia also contribute to increased platelet activity and thus can enhance the risk of thrombosis. Therefore, identification of unique mechanisms of platelet dysfunction in aging and in age-associated comorbidities is warranted to design novel antiplatelet drugs. This review outlines some of the current areas of research on aging-related mechanisms of platelet hyperactivity and addresses the clinical urgency for designing anti-platelet therapies toward novel molecular targets in the aging population. 相似文献
67.
[目的]通过现代检验技术研究筋疽(糖尿病足非缺血性坏疽)湿热毒盛证的糖脂代谢指标。[方法]收集136例筋疽(糖尿病足非缺血性坏疽)患者进行不同证型间指标的比较。[结果]湿热毒盛证患者空腹血糖(FBG)、糖化血红蛋白(HbA1c)、餐后2 h血糖(2 hPBG)、晚期糖基化终末产物(AGEs)、白蛋白(ALB)、总胆固醇(TC)、高密度脂蛋白(HDL-C)与其他证型比较存在统计学差异(P<0.05)。湿热毒盛证患者C-反应蛋白(CRP)、人可溶性血管细胞黏附分子1(sVCAM-1)与其他证型组间比较存在统计学差异(P<0.01)。[结论]筋疽(糖尿病足非缺血性坏疽)湿热毒盛证形成的原因与低营养状态下糖脂代谢紊乱引起的高血糖及持续炎症反应相关。 相似文献
68.
《Foot and Ankle Surgery》2020,26(2):193-197
BackgroundThe aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot.MethodsA retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation.ResultsForty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results.ConclusionThe non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation.Level of evidenceLevel III, case control study 相似文献
69.
Seulbi Lee Hyesook Park Soontae Kim Eun-Kyung Lee Jiyoung Lee Young Sun Hong Eunhee Ha 《International journal of hygiene and environmental health》2019,222(3):533-540
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70.
目的 探讨食管癌高、低发区食管鳞癌患者的生存状况及其影响因素。方法 收集38 741例经病理学证实为食管鳞癌患者的资料,其中,高发区患者23 273例(60.1%),低发区15 468例(39.9%)。所有患者均行食管癌根治术。运用卡方检验分析不同临床病理特征患者的组间差异,Kaplan-Meier法绘制不同临床病理特征患者的生存曲线并用Log rank进行检验。多因素Cox比例风险回归模型法分析影响生存的主要因素。结果 低发区男性患者所占比例高于高发区(P<0.001),低发区诊断年龄≥50岁食管癌患者所占比例高于高发区(P<0.001)。高发区食管鳞癌患者的整体生存优于低发区患者(P<0.001)。Cox比例风险回归模型综合分析结果表明:高低发区、性别、确诊年龄、肿瘤部位、分化程度、TNM分期和肿瘤家族史均是影响食管鳞癌患者生存的独立因素。结论 高发区食管鳞癌患者整体生存优于低发区;低发区是食管鳞癌患者预后差的独立危险因素。 相似文献