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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.
林姗 《天津教育》2021,(8):182-183
插图资源的合理利用能提高小学语文课堂的灵动性,让学生兴趣盎然,乐于学习;能辅助学生对文本的理解,提高阅读力;能培养学生的思维,提高整合能力。  相似文献   
3.
王玮 《兰台世界》2021,(3):47-50
口述档案是对个体记忆的输出和整理,是联系个体记忆和社会记忆的桥梁,它扩宽了保存历史、回忆过去的途径,使得社会记忆层次更立体、角度更多元。构建社会记忆的大背景下,高校档案人员应诠释好"口述参与者、记忆守护者、资源整合者、服务创新者"的全新角色定位,不断加强意识思维、知识结构和专业技能的自我提升和完善。  相似文献   
4.
Abstract

Digital technologies are a part of schooling, however, given the significant focus on using of digital technologies in teaching and learning, there is little evidence of wide scale transformation. It is within this context that this paper reports on a qualitative, explanatory case study of six teachers, with experience in enhancing pedagogies in a well-established ubiquitous technologies environment, consciously seeking to transform their practice to enact personalized digital learning. The findings indicate three interacting factors contributed to the degrees of transformation: teachers’ frames of reference (beliefs and attitudes), habits of mind (prior experience), and modes of transformative learning. This paper highlights how diversification of classroom roles, relationships and actions created challenges for teachers with experience integrating digital technologies in teaching and learning.  相似文献   
5.
图片命名、范畴流畅性等神经心理学测验表明,阿尔兹海默症(AD)患者普遍存在语义记忆的损伤,并随着病程的发展表现出进行性与弥散性特点。AD患者语义记忆的损伤既可能由语义知识的存储障碍造成,也可能由语义知识的提取障碍引发,还可能由存储与提取的双重损伤造成。未来研究应开发出对早期AD检测更为敏感的语义记忆测验,并采用横向与纵向多种研究技术与手段,考虑不同语言文化背景下AD患者语义损伤的情况,以综合分析AD患者语义记忆损伤的实质及其发展趋势。  相似文献   
6.
作为一种开放、智能、灵活的数字化学习工具,开源硬件是培养中小学生设计思维能力的重要载体。为了探索设计思维培养与开源硬件教学实践双向耦合的新路径,文章首先解析了设计思维概念内涵,对典型设计思维培养模型及特征进行分析,并将其解构为更具显性化操作意义的五大核心能力:换位思考、抽象定义、创意构想、原型迭代和迁移应用;其次,汲取设计型学习理论核心要义,借鉴“基于设计的双循环探究模型”,构建了设计思维导向的开源硬件教学模式,从“调查/探究”“设计/再设计”“反思”三个循环过程对其具体应用进行阐释;最后,以“智慧校园生活”为项目主题开展开源硬件教学实践,为新版高中信息技术课程标准中“开源硬件项目设计”模块的教学实施提供范例。  相似文献   
7.
为科学规制公共图书馆参与数字出版过程中长期存在的供需地位失衡、博弈机制失衡、版权流转失衡等矛盾,本文以区块链中的分布存储、共识机制、智能合约3类核心技术为基础,分析了旨在动态平衡公共图书馆参与数字出版版权利益博弈的可行思路,同时结合区块链各层级结构特点提出面向促进资源供需节点间地位平衡、达到版权收益帕累托最优、提高数字版权交易可靠性的实践策略,以期为公共图书馆参与数字出版过程中及时遏制侵权行为、保障版权交易利益相关者权益提供参考。  相似文献   
8.
The business process outsourcing industry has got disrupted, first by the significant shift in value creation activities from the clients to the service providers, and second by pervasive digital penetration, resulting in the emergence of Digital Transformational Outsourcing (DTO). Service providers now play a more significant role, making their capabilities important. In the new context, service providers require a uniquely different set of dynamic capabilities to handle end-to-end business functions on behalf of their clients while delivering digital value propositions.We study 26 of the largest global business process outsourcing providers to conceptualise and identify six dynamic capabilities of service providers salient in the new context, i.e., consultative, orchestration, insights, network management, knowledge access, and standardisation. Interviews conducted with industry experts provided evidence in support of the identified dynamic capabilities. A novel firm capability dataset was created using secondary data, and using fuzzy-set Qualitative Comparative Analysis (fsQCA), we identify configurations for high and low performance and find them to vary by the firm's broad/narrow scope.  相似文献   
9.
Cloud computing is a popular outsourcing solution for organizations to support the information management during the life cycle of digital information goods. However, outsourcing management with a public provider results in a lack of control over digital products, which could produce incidents such as data unavailability during service outages, violations of confidentiality and/or legal issues. This paper presents a novel distribution model of digital products inspired by lean supply chain principles called CloudChain, which has been designed to support the information management during digital product lifecycle. This model enables connected networks of customers, partners and organizations to conduct the stages of digital product lifecycle as value chains. Virtual distribution channels are created over cloud resources for applications of organizations to deliver digital products to applications of partners through a seamless information flow. A configurable packing and logistic service was developed to ensure confidentiality and privacy in the product delivery by using encrypted packs. A chain management architecture enables organizations to keep tighter control over their value chains, distribution channels and digital products. CloudChain software instances were integrated to an information management system of a space agency. In an experimental evaluation CloudChain prototype was evaluated in a private cloud where the feasibility of applying supply chain principles to the delivery of digital products in terms of efficiency, flexibility and security was revealed.  相似文献   
10.
《Research Policy》2019,48(8):103696
Digital-technology usage in dynamic and complex work practices is a core phenomenon in innovation research. There are, however, few detailed analyses of how people organize the use of digital tools in their work practices. We aim to offer more insight into how individual actors use digital technology, how these actors organize its use in collectives, and how they organize their work with that of other actors in order to realize collective-level goals. We implemented a qualitative research design, based on interviews in architectural firms complemented with observations and archival data. By analyzing interactions of multiple individual actors with digital technology, we found that actors organize usage in collectives through activities that we call configuring-in-use and reflecting; and that they combine these two organizational activities in order to realize collective-level goals. We identify the combination of these organizational activities as configurational usage. We contribute to literature on the usage of pervasive digital technology by providing a detailed empirical investigation of organized usage of digital technology. Furthermore, we refine the conceptualization of configurational usage, improving understanding of core processes of digital innovation.  相似文献   
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