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991.
Minqi Liao Yingjun Mu Xin Su Lu Zheng Shiwen Zhang Hongen Chen Shan Xu Junrong Ma Ruiqing Ouyang Wanlin Li Chen Cheng Jun Cai Yuming Chen Changyi Wang Fangfang Zeng 《Nutrients》2022,14(20)
This study aimed to evaluate the potential associations of dietary BCAAs (isoleucine, leucine, and valine) with physical function in the elderly Chinese population. A validated semiquantitative food frequency questionnaire and anthropometric and physical function measurements were used to collect data. We modeled trends in physical function indicators for BCAA quartiles using multivariate linear regression models. Among 4336 (43.97% men) participants aged 72.73 ± 5.48 years, a higher dietary intake of BCAAs was positively associated with increased handgrip strength (all p trends < 0.001), shorter times for 4-m fast walking (all p trends < 0.001) and repeated chair rises (all p trends < 0.001). No linear association was found between subtypes of amino acids and any physical functions (all p trends > 0.05). Individuals in the highest quartiles of BCAA intake had a reduced risk of developing low muscle strength, and the multiadjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for women and men were 0.50 (0.38–0.65) and 0.67 (0.50–0.91), respectively. Similarly, higher BCAA consumption was associated with a lower risk of developing low physical performance (4-m walking speed: OR = 0.68 [0.50–0.93]; repeated chair rises: OR = 0.66 [0.54–0.81]). Higher dietary BCAA intake might be beneficial for physical function in the elderly population. 相似文献
992.
993.
Certain mammalian species are resistant to cancer, and a better understanding of how this cancer resistance arises could provide valuable insights for basic cancer research. Recent technological innovations in molecular biology have allowed the study of cancer‐resistant mammals, despite the fact that they are not the classical model animals, which are easily studied using genetic approaches. Naked mole‐rats (NMRs; Heterocephalus glaber) are the longest‐lived rodent, with a maximum lifespan of more than 37 years, and almost never show spontaneous carcinogenesis. NMRs are currently attracting much attention from aging and cancer researchers, and published studies on NMR have continued to increase over the past decade. Cancer development occurs via multiple steps and involves many biological processes. Recent research on the NMR as a model for cancer resistance suggests that they possess various unique carcinogenesis‐resistance mechanisms, including efficient DNA repair pathways, cell‐autonomous resistance to transformation, and dampened inflammatory response. Here, we summarize the molecular mechanisms of carcinogenesis resistance in NMR, which have been uncovered over the past two decades, and discuss future perspectives. 相似文献
994.
BACKGROUNDThe effects of T-cell immunoglobulin mucin molecule-3 (Tim-3), transforming growth factor β (TGF-β), and chemokine-12 (CXCL12) expression on the prognosis of patients with diffuse large B-cell lymphoma (DLBCL) have not been elucidated.AIMTo examine the correlation between Tim-3, TGF-β and CXCL12 expression and DLBCL prognosis.METHODSLymph node tissues of 97 patients with DLBCL and 93 normal-response hyperplastic lymph node tissues treated from January 2017 to May 2019 were selected as the DLBCL and control groups, respectively. The expression of Tim-3, TGF-β, and CXCL12 was detected immunohistochemically. Patients were followed up for 3 years, and progression-free survival was recorded. Cox multifactorial analysis was performed to analyze the risk factors for poor prognosis.RESULTSThe positive expression rates of Tim-3, TGF-β, and CXCL12 were higher in DLBCL tissues than in non-cancerous (control) tissues (P < 0.05). One-year post-surgery, the positive expression rates of Tim-3, TGF-β, and CXCL12 were higher in patients with effective treatment than in those with ineffective treatment (P < 0.05). The 3-year progression-free survival of 97 patients with DLBCL was 67.01% (65/97). Univariate analysis revealed that clinical stage, bone marrow infiltration, International Prognostic Index (IPI) score, Tim-3 positivity, TGF-β positivity, and CXCL12 positivity were associated with poor prognosis (P < 0.05). Multivariate Cox regression analysis demonstrated that clinical stage III–IV, bone marrow infiltration, mediate-to-high-risk IPI scores, Tim-3 positivity, TGF-β positivity, and CXCL12 positivity were independent risk factors affecting prognosis (P < 0.05).CONCLUSIONDLBCL tissues exhibit high positive expression of Tim-3, TGF-β, and CXCL12, and a high expression of all three indicates a poor prognosis. 相似文献
995.
分析当前我国医学人文类慕课的建设现状,促进医学人文慕课优质课程资源共享,为课程设计规划提供信息参考。采用数理统计法、思维导图分析法对疫情期间17个在线课程平台上的42门医学人文慕课进行分析,结果显示:①医学人文慕课规模和数量有待扩增;②慕课建设存在地域不均衡性,华东地区建设最多;③慕课师资以团队授课为主,高级职称教师为团队主力,且部分教师团队为多学科背景;④课程内容中人文知识和能力相关教学内容丰富,但需适当增加医学人文精神认知相关内容。根据以上分析结果,建议医学人文慕课建设注重系统性和规范性,配备多学科专业背景师资团队,注意做好课程设计和规划,充分关注学习者的反馈与评价,以发现不足之处。 相似文献
996.
利用SWOT理论分析疫情防控期间教学医院开展在线教学的内外部竞争环境和竞争条件。在综合性大学附属某医院开展临床医学课程在线教学,具有资源优势、组织优势和平台优势;但也存在临床医学专业的课程特殊性、临床教学医院的教师身份特殊性、疫情防控背景下在线教学的软硬件特殊性等劣势;为医院对标国家一流课程建设、发挥课程思政在教学阵地的主作用、营造主动型学习生态圈提供了发展基础;也对未来教学模式、教学管理模式、教学空间变革提出了挑战。基于此,提出推进医院医学教育信息化建设;全面提升教师信息素养;筑构适应于医院管理环境的教育信息化平台;搭建基于智慧教学空间的多元评价体系;基于多学科建设线上线下混合式课程体系等措施,以推进医院医学教育信息化建设和提升教学管理效率,促进“新医科”建设。 相似文献
997.
Kentaro Hara Shohei Kaneko Taichi Ishioka Shohei Tobinaga Shigehiko Urabe Akiha Nakao Kozue Hamada Kyoko Nagaoka Miwa Taniguchi Michiko Yamaguchi Hiroaki Takeshita Junichi Tanaka Hiromi Kuroda Emi Matsuura Yuji Ishimatsu Sumihisa Honda Terumitsu Sawai 《Medicine》2023,102(9)
The perfusion index (PI) cutoff value before anesthesia induction and the ratio of PI variation after anesthesia induction remain unclear. This study aimed to clarify the relationship between PI and central temperature during anesthesia induction, and the potential of PI in individualized and effective control of redistribution hypothermia. This prospective observational single center study analyzed 100 gastrointestinal surgeries performed under general anesthesia from August 2021 to February 2022. The PI was measured as peripheral perfusion, and the relationship between central and peripheral temperature values was investigated. Receiver operating characteristic curve analysis was performed to identify baseline PI before anesthesia, which predicts a decrease in central temperature 30 minutes after anesthesia induction, and the rate of change in PI that predicts the decrease in central temperature 60 minutes after anesthesia induction. In cases with a central temperature decrease of ≥ 0.6°C after 30 minutes, the area under the curve was 0.744, Youden index was 0.456, and the cutoff value of baseline PI was 2.30. In cases with a central temperature decrease of ≥ 0.6°C after 60 minutes, the area under curve was 0.857, Youden index was 0.693, and the cutoff value of the PI ratio of variation after 30 minutes of anesthesia induction was 1.58. If the baseline PI is ≤ 2.30 and the PI 30 minutes after anesthesia induction is at least 1.58-fold the PI ratio of variation, there is a high probability of a central temperature decrease of at least 0.6°C within 30 minutes after 2 time points. 相似文献
998.
999.
目的观察大鼠肺血栓栓塞症(PTE)后不同时间血浆尿激酶型纤溶酶原激活物(uPA)和尿激酶型纤溶酶原激活物受体(uPAR)的动态变化,并探讨两者与血栓自溶率的相关性。方法经颈外静脉注入加热125I-标记纤维蛋白原自体血栓,复制大鼠PTE模型,随机分组如下:1)正常对照组;2)PTE组:又分为PTE 4 h组(PTE 4 h)、PTE 24 h组(PTE 24 h)、PTE 3 d组(PTE 3d)、PTE 5 d组(PTE 5 d),即分别在造模成功后观察4 h2、4 h3、d、5 d后处死小鼠,留取血浆标本测定uPA、uPAR的水平;留取左肺观察肺组织病理改变;留取心脏、肺脏、全血以计算血栓自溶率。结果血浆uPA、uPAR水平在PTE后4 h略有上升(P>0.05),PTE后24 h明显增加(P<0.05),3 d时最高(P<0.01),5 d时开始下降,但仍明显高于正常对照组(uPAP<0.05,uPARP<0.01);PTE后4 h组、24 h组、3 d组血浆uPA质量浓度与血栓自溶率正相关(4 hr=0.758,P<0.05;24 hr=0.764,P<0.05;3 dr=0.778,P<0.05),血浆uPAR质量浓度与血栓自溶率正相关(4 hr=0.701,P<0.05;24 hr=0.764,P<0.05;3 dr=0.777,P<0.05)。肺组织病理改变:PTE后4 h有少量继发血栓形成,血栓及血管壁内可见白细胞浸润;PTE后3 d、5 d见注入的血凝块明显溶解,代之以新形成的血栓。结论PTE后血浆uPA、uPAR水平增加,促进内源性纤维蛋白溶解。 相似文献
1000.
反相高效液相色谱法测定二妙散中生物碱的含量 总被引:1,自引:0,他引:1
采用反相高效液相色谱法,以盐酸小檗碱、盐酸巴马汀、盐酸药根碱、黄柏碱、HB-1为定量指标,测定二妙散中上述各成分的含量。色谱柱Nucleosil-ODS;流动相为甲醇-磷酸盐缓冲液-十二烷基硫酸钠(60∶40∶0.1);流速1.0ml/min;检测波长264nm。盐酸小檗碱、盐酸巴马汀和HB-1的加样回收率分别为99.12%,98.35%,99.82%,RSD分别为3.42%,3.15%,3.74%。测得二妙散中各生物碱含量分别为:小檗碱0.914%,巴马汀0.609%,药根碱0.0247%,黄柏碱0.0839%,HB-10.313%。 相似文献