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1.
目的探讨自主运动调节tau蛋白激酶和tau蛋白磷酸酶的基因表达,抑制APP/PS1转基因小鼠海马tau蛋白过度磷酸化,进而改善学习记忆能力的分子机制。方法C57系APP/PS1转基因小鼠随机分为运动组(TE)与对照组(TC);C57系野生小鼠亦随机分为运动组(E)与对照组(C)。其中,TE组和E组小鼠从3月龄开始,给予16周的跑轮运动装置,TC组和C组小鼠不施加运动干预,作为相应对照组。Morris水迷宫实验检测APP/PS1转基因小鼠的空间学习记忆能力,Western Blot实验检测海马磷酸化tau蛋白(P-tau)水平,RT-PCR实验检测海马tau蛋白及tau蛋白激酶GSK-3β和CDK-5,tau蛋白磷酸酶PP2A和PP1 mRNA表达。结果(1)与TC组相比,TE组小鼠Morris水迷宫游泳潜伏期显著性降低(P<0.05),平台象限的游泳时间百分比显著性增加(P<0.05),穿越原平台位置的次数极显著性增加(P<0.01);(2)与TC组相比,TE组小鼠海马总tau蛋白mRNA表达显著下调(P<0.05),Ser202位点和Thr181位点P-tau蛋白表达均显著性下调(P<0.05);(3)与TC组相比,TE组小鼠海马tau蛋白磷酸化激酶GSK-3β(P<0.01)和CDK-5(P<0.05)mRNA表达显著性下调,tau蛋白磷酸酶PP2A(P<0.01)和PP1(P<0.01)mRNA表达极显著性下调。结论16周自主运动通过下调tau蛋白激酶表达、上调tau蛋白磷酸酶表达,抑制APP/PS1转基因小鼠海马tau蛋白的过度磷酸化,进而促进海马神经细胞功能,改善转基因小鼠学习记忆。说明自主运动可通过调节脑的分子生物学机制,促进认知功能的改善和提升,预防和缓解阿尔茨海默病。  相似文献   
2.
邹吉权 《成人教育》2021,41(4):46-52
1+X证书制度是提高技术技能人才培养质量的重要举措,是深化复合型技术技能人才培养培训模式和评价模式改革的重要途径,是探索构建国家资历框架的基础性工程。1+X证书制度涉及多方利益主体,事关人才培养体系重构。基于1+X证书制度的实施,提出“四方联动、五链耦合”人才培养机制。所谓“四方联动”,是指政府、学校、企业、培训评价组织四方高度协同、实时联动;所谓“五链耦合”,是指基于1+X证书重构教学流程、再造课程结构,人才培养体系中的智慧型岗位、模块化课程、结构化团队、项目化教学、复合型人才五个环节高度耦合、环环相扣,形成复合型技术技能人才培养新机制,以期为中国特色高水平高职学校建设提供参考借鉴。  相似文献   
3.
BackgroundCecropin P1, acting as an antimicrobial, has a broad-spectrum antibacterial activity with some antiviral and antifungal properties. It is a promising natural alternative to antibiotics which is originally isolated from the pig intestinal parasitic nematode Ascaris suum. Many studies have shown that Cecropin P1 is helpful for the prevention or treatment of clinical diseases. Therefore, it is very necessary to establish a safe, nontoxic, and efficient expression method of Cecropin P1.ResultsThe results indicated that the recombinant protein was about 5.5 kDa showed by Tricine–SDS–PAGE and Western blot. And Cecropin P1 was efficiently secreted and expressed after 12 h of induction, with an increasing yield over the course of the induction. Its maximum concentration was 7.83 mg/L after concentration and purification. In addition, in vitro experiments demonstrated that Cecropin P1 not only exerted a strong inhibitory effect on Escherichia coli, Salmonella sp., Shigella sp., and Pasteurella sp., but also displayed an antiviral activity against PRRSV NADC30-Like strain.ConclusionsCollectively, the strategy of expressing Cecropin P1 in Saccharomyces cerevisiae is harmless, efficient, and safe for cells. In addition, the expressed Cecropin P1 has antiviral and antibacterial properties concurrently.How to cite: Jiang R, Zhang P, Wu X, et al., Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial and antiviral activity in vitro. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2020.12.006  相似文献   
4.
“1+X”证书制度是职教20条中重要改革部署和重大创新。落实职业院校学历教育和培训并举并重,坚持学历教育与职业培训相结合,促进书证融通。严把证书标准和人才质量两个关口,规范培养培训过程。从试点做起,通过改革稳步推进,总结经验、完善机制、防控风险。以财务岗位为例,以课证融通为切入点,系统探索“1+X”证书制度的内涵、“1”与“X”的关系、“X”证书与职业资格证书的区别,对课证融通中职业能力标准体系建设,培训体系和课程体系的建设进行深入研究。  相似文献   
5.
Language education has often been conducted based on monoglossic ideologies that keep L1 and L2 separate, a practice that receives growing criticism as out of sync with today’s multilingual globalized world. Informed by interdependence hypotheses and translanguaging theory, this research study explored the effects of a pluri-centric approach to learning L1 and L2 simultaneously. Through a bilingual intervention course with data collected from interviews, parents’ logbooks, observation field notes, questionnaires, and L1 and L2 reading and writing tests, this case study (n = 9) revealed that the approach effectively improved learners’ L1 and L2 proficiency, learning behaviour outside the classroom, self-efficacy, and confidence. Overall, the participants also perceived the bilingual course as effective, efficient, and innovative. The study provides a basis to reflect upon transferrable skills and core underlying proficiency as powerful concepts to draw upon in enhancing bilingual proficiency and effecting positive changes in learners’ behaviour and psychological well-being.  相似文献   
6.
王孝梅 《科教导刊》2021,(1):105-106
针对部分学生认为学习高等数学枯燥乏味,甚至产生厌烦、逃避的情况,提出6+1高等数学教学法.6+1高等数学教学法改变了传统高等数学教学中"教师讲、学生听"的教学模式,且与"学生为主体,教师为主导"的现代教学理念相吻合.通过"导""议""展""评""理""研""思"七环节,激发学生学习高等数学兴趣,培养学生的自主学习意识,提高学生的高等数学逻辑思维和探究能力.  相似文献   
7.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
8.
基于政策工具理论与三螺旋理论构建出二维政策分析框架,对《关于在院校实施“学历证书+若干职业技能等级证书”制度试点方案》的政策文本进行内容编码、归类整理和数据统计发现,职业教育1+X证书制度的政策工具使用频率的分布明显不均衡。供给型政策工具使用过溢,内部结构明显失衡;环境型政策工具的配置比例与内部结构均比较合理;需求型政策工具相对欠缺,内部结构差距悬殊;国家对体系建设、多元参与和人才培养的关注较多,却忽视了态度立场的引领与财政支持的保障。未来应适当缩减供给型政策工具的使用频率,协调不同政策工具的分布比例,发挥需求型政策工具的拉动作用和环境型政策工具的调控作用,实现不同政策工具内部结构的均衡化发展。同时,也要为职业教育发展提供思想指引和财政支撑。  相似文献   
9.
A current challenge for the scientific community is the choice of appropriate policies to reduce the rate of false positives. Existing proposals differ in whether to prioritize tackling omission through transparency requirements, punishing more severe transgressions, or possibly both. We use a formal model to evaluate these possible solutions. We find that a policy that prohibitively increases the cost of ‘misdemeanor’ types of questionable research practices robustly decreases the overall rate of researcher misconduct, because the rate of ‘felonies’, such as fabrication, also decreases. Therefore proposals that aim to prevent lying by omission by enforcing reporting guidelines are likely to be effective in reducing researcher misconduct, but measures such as government audits (purported to counteract pure fraud) can backfire. Moreover, we find that an increase in the rewards of publication need not increase overall misconduct.  相似文献   
10.
针对卫星扩频通信系统的时间同步需求,提出一种基于GNSS授时的卫星通信前向链路间接时间同步方法。通过由星地自发自收链路与锁相环构成的钟差间接修正环路,对发送端码时钟进行闭环修正。这将使前向链路信号起始扩频码相位在到达接收端的时刻与卫星导航授时模块输出的1 PPS保持精确稳定的同步。实现了不需要位同步的扩频信号定时接收。分析并得到间接时间同步误差表达式及其与环路带宽的变化关系,给出使同步误差最小的最优环路带宽值。星地链路试验结果表明时间同步误差随环路带宽的变化关系与理论分析一致,最佳环路带宽对应的钟差间接修正环路秒脉冲1σ同步误差约为20 ns,验证了本方法的有效性。在此同步误差条件下,接收端成功地进行扩频伪码的同步和电文解调,实现了卫星导航授时对通信的辅助。  相似文献   
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