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71.
以培养创新型人才为目标,大连医科大学制定实施了“5+3”创新人才培养改革方案,以导师制培养为载体,在医学本科教育全过程中,制定分阶段创新能力培养体系,涵盖课程、讲座、实验设计、论文等基本科研能力训练,强化本科生科研能力培养。通过对首届“5+3”学生阶段性培养成果的统计学分析发现,“5+3”学生发表中文期刊、SCI,主持国家级创新项目、省级创新项目的比例均显著高于普通5年制学生,差异具有统计学意义(P<0.05)。虽然实施过程中存在一些问题和不足,但以导师制为核心的科研基础训练对提高学生科研思维和创新能力效果显著,对培养医学创新型人才具有可实施性。 相似文献
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Quantitative chemical exchange saturation transfer (qCEST) MRI – omega plot analysis of RF‐spillover‐corrected inverse CEST ratio asymmetry for simultaneous determination of labile proton ratio and exchange rate 下载免费PDF全文
Renhua Wu Gang Xiao Iris Yuwen Zhou Chongzhao Ran Phillip Zhe Sun 《NMR in biomedicine》2015,28(3):376-383
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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AbstractThe autoimmune condition Hashimoto’s thyroiditis (HT) is a disease wherein lymphocytes mediate the autoimmune damage and destruction of the thyroid gland. There are currently no effective means of treating HT, with the primary strategies of thyroid hormone therapy, surgery, or immunomodulatory therapy being associated with serious risks and side effects. There is thus a clear and urgent need to identify novel treatments for HT. In this study, we utilize female SD rats induced HT to evaluated the ability of transplanted MSCs to regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. The results showed that Rats in the HT model group exhibited increased thyroid autoantibody levels consistent with successful model development, whereas these levels were lower in rats treated with MSCs. There were also fewer thyroid lesions and less lymphoid infiltration of the thyroid in MSC-treated rats relative to HT model rats, as well as fewer Th17 cells and more Treg cells – an observation consistent with the cytokine analyses. All of these showed that MSCs can regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. It suggested that transplanted MSCs could be a potential immunotherapy strategy for the treatment of Hashimoto’s thyroiditis. 相似文献
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Guowei Zhang Fenger Sun Heping Liu Xiaoyan Ren Hong Xu Mingjie Wang Yizheng Fu 《Materials》2021,14(9)
The structural properties, elastic anisotropy, electronic structures and work function of D022-type Al3TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al3Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D022-type Al3TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al3La is the strongest, while that of Al3Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young’s modulus are further explained by the work function. Finally, the experimental design proves that D022-Al3Ta has an excellent strengthening effect. 相似文献
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目的:探讨术前预后营养指数(prognostic nutritional index,PNI)对肺癌术后并发症风险的预测价值。方法:回顾分析2015年12月至2018年3月于我院行手术治疗的非小细胞肺癌患者180例,收集患者的临床资料以及术后并发症的发生情况,采用Logistic回归分析患者术后并发症的影响因素。结果:多因素Logistic回归分析表明,术前低PNI值是术后并发症Clavien-Dindo评分≥II级的独立危险因素(OR:1.10,95%CI:1.02~1.17,P=0.023);根据术前PNI值将患者分为三组,分别为PNI≥50组(n=113)、45≤PNI<50组(n=47)、PNI<45组(n=20),各组术后并发症Clavien-Dindo评分≥II级以及Clavien-Dindo评分≥III级发生的比例分别为22.1%、40.4%、40.0%和6.2%、17.0%、25.0%,不同PNI值术后并发症发生率存在显著差异;PNI值可作为术后并发症发生风险及气胸、肺外感染的独立危险因素。结论:PNI值可作为肺癌患者术后并发症风险的有效预测因子。 相似文献
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The associations between saturated fatty acid (SFA) consumption and risk of breast cancer (BC) remains inconclusive. Therefore, we conducted this meta-analysis to determine the quantitative relations between dietary SFA intake and incidence of BC.Literatures published up to April 2015 were systematically screened through Pubmed and Web of Science. Relevant publication quality was evaluated by conducting the Newcastle-Ottawa scale. We used fixed effects models or random effect models to calculate the summary relative risks (RRs) and odds ratios (ORs), and conducted sensitivity analyses and evaluated the publication bias.We identified a total of 52 studies (24 cohort studies and 28 case–control studies), with over 50,000 females diagnosed with BC. The associations between dietary SFA intake and risk of BC were 1.18 for case–control studies (high vs low intake, 95% confidence interval [CI] = 1.03–1.34) and 1.04 for cohort studies (95% CI = 0.97–1.11). When restricted analyses to population-based studies, positive associations were observed for both cohort (RR [95% CI] = 1.11 [1.01–1.21]) and case–control studies (OR [95% CI] = 1.26 [1.03–1.53]). Additionally, for case–control studies, significant positive associations between higher SFA intake and BC risk were observed for Asian (OR [95% CI] = 1.17 [1.02–1.34]) and Caucasian (OR [95% CI] = 1.19 [1.00–1.41]), as well as for postmenopausal women (OR = 1.33, 95% CI: 1.02–1.73). In contrast, higher dietary SFA intake was not associated with risk of BC among premenopausal women, in cohort studies or hospital-based studies.A positive association between higher dietary SFA intake and postmenopausal BC risk was observed in case–control but not in cohort studies. More studies are warranted to confirm these findings. 相似文献