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SQL or NoSQL—Practical Aspect and Rational behind Choosing Data Stores
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作者 Sourabh Sethi Sarah Panda 《Journal of Computer and Communications》 2024年第8期1-20,共20页
Data storage solutions are a crucial aspect of any application, significantly impacting data management and system performance. This article explores the rationale behind utilizing both SQL and NoSQL databases, addres... Data storage solutions are a crucial aspect of any application, significantly impacting data management and system performance. This article explores the rationale behind utilizing both SQL and NoSQL databases, addressing key questions about when each type is preferable. The background emphasizes the importance of selecting the appropriate database technology to meet specific application requirements. The purpose of this research is to provide a comprehensive guide for choosing between SQL and NoSQL databases based on various factors, including workload characteristics, scalability needs, and consistency requirements. To achieve this, we examine different strategies for implementing SQL and NoSQL databases in large-scale distributed applications and systems. The research method involves a comparative analysis of the features, advantages, and limitations of both database types. We specifically focus on scenarios involving read-heavy versus write-heavy systems and the trade-offs between availability and consistency. The results of this research indicate that SQL databases, with their relational structure and ACID compliance, are ideal for applications requiring complex queries and data integrity. In contrast, NoSQL databases, offering schema flexibility and horizontal scalability, are better suited for managing extensive datasets and high-velocity data ingestion. In conclusion, the selection of a database depends on the specific needs of the application. SQL databases are preferred for transactional systems with complex relationships, while NoSQL databases excel in scenarios demanding flexibility and scalability. The study provides insights into hybrid approaches, leveraging both database types to optimize system performance. 展开更多
关键词 SQLData stores NO-SQLData stores ACID BASE RUM Conjecture
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High performance carrier stored trench bipolar transistor with dual shielding structure
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作者 张金平 邓浩楠 +2 位作者 朱镕镕 李泽宏 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期576-582,共7页
We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in t... We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON). 展开更多
关键词 carrier stored trench bipolar transistor(CSTBT) dual shielding structure gate-collector capacitance power loss
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Numerical Simulation about the Characteristics of the Store Released from the Internal Bay in Supersonic Flow
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作者 Xiaohui Cheng Haiqing Si +1 位作者 Yao Li Peihong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1729-1742,共14页
To understand the influence of the initial release conditions on the separation characteristics of the store and improve it under high Mach number(Ma=4)flight conditions,the overset grid method and the Realizable k−ε... To understand the influence of the initial release conditions on the separation characteristics of the store and improve it under high Mach number(Ma=4)flight conditions,the overset grid method and the Realizable k−εturbulence model coupled with an equation with six degrees of freedom are used to simulate the store released from the internal bay.The motion trajectory and the attitude angle of the store separation under the conditions of different centroid,velocity,height and control measures are given by the calculated result.Through analysis,the position of the centroid will affect the separation of the store,which needs to be considered in the design.Increasing the launching height is conducive to the separation of the store.If the store has an initial velocity,it can leave the internal bay more quickly and reduce the probability of collision with the wall.Cylindrical rod and slanted aft wall control measures can improve the attitude of the store and make the store fall more smoothly. 展开更多
关键词 Separation of the store motion trajectory overset grid equation with six degrees of freedom control measures
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Development Mode of Urban Grassroots Libraries under the Background of Lifelong Learning:Inspiration from Idea Stores in London
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作者 WANG Hui CHAI Pengyu 《Journal of Landscape Research》 2023年第3期85-89,共5页
The urban grass-roots library is an important part of the public cultural service system,and also a place to carry out national reading and lifelong learning,which is of great significance to the construction of a lea... The urban grass-roots library is an important part of the public cultural service system,and also a place to carry out national reading and lifelong learning,which is of great significance to the construction of a learning society.In this paper,the development and evolution of urban grassroots libraries in China are reviewed,and the current situation and usage issues of grassroots libraries in Beijing are analyzed.Moreover,the development strategy of idea stores in London,UK is studied,and characteristics are summarized,and possible references are sought.In the new era,urban grassroots libraries should integrate into communities with multiple functions and play a more sufficient role in public education,learning and training,and other aspects. 展开更多
关键词 Grassroots library Grassroots cultural facilities Idea store Lifelong learning
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考虑倒箱的Auto Store仓储拣选系统提箱作业优化
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作者 师浩森 陈航慧 +2 位作者 王皓 王晓军 杨春霞 《太原科技大学学报》 2023年第4期376-381,388,共7页
为减少Auto Store仓储拣选系统的倒箱作业时间,提高其提箱作业效率,在已知料箱存储状态及订单商品信息的条件下,研究了Auto Store仓储拣选系统提箱作业优化的问题。以提箱作业时间来衡量Auto Store仓储拣选系统作业效率,建立以最短提箱... 为减少Auto Store仓储拣选系统的倒箱作业时间,提高其提箱作业效率,在已知料箱存储状态及订单商品信息的条件下,研究了Auto Store仓储拣选系统提箱作业优化的问题。以提箱作业时间来衡量Auto Store仓储拣选系统作业效率,建立以最短提箱作业时间为目标的整数规划模型,设计启发式算法对模型进行求解,提出问题下界的约束条件及求解方法,同时,通过算例比较启发式算法与理论下界的差异,表明倒箱作业规则对Auto Store仓储拣选系统提箱作业效率影响较大,优化倒箱作业规则,可提高其提箱作业效率,为Auto Store的倒箱作业优化提供了理论支持。 展开更多
关键词 AUTO store 仓储拣选 倒箱作业 启发式算法
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基于双边市场理论的苹果App Store模式研究 被引量:19
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作者 张利斌 张广霞 《计算机工程与科学》 CSCD 北大核心 2012年第4期188-192,共5页
从双边市场理论的定义、识别条件、特征、分类和平台企业战略等角度,分析了苹果Appstore模式的特征及平台战略。
关键词 双边市场 APP store模式
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32位RISC微处理器Load/Store部件的设计 被引量:2
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作者 孙华锦 高德远 +1 位作者 樊晓桠 王毅 《计算机工程与应用》 CSCD 北大核心 2003年第25期16-17,113,共3页
简要介绍了一个32位RISC微处理器芯片ARS03的体系结构,阐述了处理器内部各个模块的功能。着重讨论了其中的Load/Store部件的设计,以及对关键路径的优化措施。Verilog仿真、综合和静态时序分析的的结果表明设计达到了预定要求。目前ARS0... 简要介绍了一个32位RISC微处理器芯片ARS03的体系结构,阐述了处理器内部各个模块的功能。着重讨论了其中的Load/Store部件的设计,以及对关键路径的优化措施。Verilog仿真、综合和静态时序分析的的结果表明设计达到了预定要求。目前ARS03微处理器已经进入后端流程,不久就将使用0.25微米的工艺进行流片。 展开更多
关键词 微处理器 RISC Load/store部件
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文化创意构想下的社区图书馆功能拓展——以Idea Store为蓝本的思考和启示 被引量:4
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作者 杨祖逵 《国家图书馆学刊》 CSSCI 北大核心 2013年第4期23-26,43,共5页
英国伦敦的Idea Store从其诞生起,通过实现文化与生活的真正融合、实现用户全程体验等诸多方面的创新,突破了原有图书馆模式的桎梏。我国社区图书馆的未来发展可以借鉴其发展模式,通过可持续发展、多功能化建设等方面的实践,实现在文化... 英国伦敦的Idea Store从其诞生起,通过实现文化与生活的真正融合、实现用户全程体验等诸多方面的创新,突破了原有图书馆模式的桎梏。我国社区图书馆的未来发展可以借鉴其发展模式,通过可持续发展、多功能化建设等方面的实践,实现在文化创意下的功能拓展。 展开更多
关键词 IDEA store 社区图书馆 功能拓展
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新型无人仓AutoStore的货物合箱方法研究 被引量:1
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作者 杨玮 张子涵 +1 位作者 张晓楠 马伟 《包装工程》 CAS 北大核心 2022年第17期174-183,共10页
目的为减少AutoStore系统在共同存储策略下的订单处理时间,解决经营品类繁多,但仓储面积有限的企业货物存储问题。方法提出货物合箱的存储方法,设计关联规则挖掘算法与混沌种子优化算法的混合优化算法进行求解。从机器人翻箱操作、料箱... 目的为减少AutoStore系统在共同存储策略下的订单处理时间,解决经营品类繁多,但仓储面积有限的企业货物存储问题。方法提出货物合箱的存储方法,设计关联规则挖掘算法与混沌种子优化算法的混合优化算法进行求解。从机器人翻箱操作、料箱的分配规则、系统布局三方面进行分析,结合AutoStore运作规律,建立以机器人拣货行走距离最短为目标函数的数学模型,通过Apriori算法输出货物热度,输入混沌种子算法,得到储位分配结果,实现联动决策。在基本种子算法的迭代中加入混沌序列,帮助种子避开局部极小值。结果实例分析表明,货物合箱方法能够显著减少共同存储下AutoStore系统的订单处理时间,缩小与指定存储策略订单处理时间的差距,与粒子群算法和基本种子优化算法相比,混沌种子优化算法的优化效率更高、稳定性更好。结论文中的研究为经营品类繁多,但仓储面积有限的企业提供了一种更适合的货物存储策略,具有较强的操作性和实际意义。 展开更多
关键词 Autostore系统 存储策略 Apriori关联规则挖掘算法 混沌种子优化算法
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New insights into store-independent Ca^(2+) entry: secretory pathway calcium ATPase 2 in normal physiology and cancer 被引量:3
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作者 Ming-Ye Feng Rajini Rao 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第2期71-74,共4页
Recent studies in secretory pathway calcium ATPases (SPCA) revealed novel functions of SPCA2 in interacting with store-operated Ca2+ channel Oral I and inducing Ca2+ influx at the cell surface. Importantly, SPCA2-... Recent studies in secretory pathway calcium ATPases (SPCA) revealed novel functions of SPCA2 in interacting with store-operated Ca2+ channel Oral I and inducing Ca2+ influx at the cell surface. Importantly, SPCA2-mediated Ca2+ signaling is uncoupled from its conventional role of Ca2+-ATPase and independent of store-operated Ca2+ signaling pathway. SPCA2-induced store-independent Ca2+ entry (SICE) plays essential roles in many important physiological processes, while unbalanced SICE leads to enhanced cell proliferation and tumorigenesis. Finally, we have summarized the clinical implication of SICE in oral cancer prognosis and treatment. Inhibition of SICE may be a new target for the development of cancer therapeutics. 展开更多
关键词 Ca2+ signaling human cancers store-independent Ca2+ entry store-operated Ca2+ entry
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浅谈“App store”商业模式 被引量:19
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作者 黄放 《价值工程》 2011年第14期144-145,共2页
本文主要描述了较为成功的应用程序商店——苹果公司的"App store",并对其商业模式加以分析讨论,探讨了直接复制和替代模仿建立应用程序商店的问题,并说明了"App store"商业模式的不可复制性。最后,针对中国企业发... 本文主要描述了较为成功的应用程序商店——苹果公司的"App store",并对其商业模式加以分析讨论,探讨了直接复制和替代模仿建立应用程序商店的问题,并说明了"App store"商业模式的不可复制性。最后,针对中国企业发展应用程序商店提出了建议。 展开更多
关键词 Appstore 商业模式 应用程序商店
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基于App Store平台的企业价值链研究 被引量:4
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作者 汪易易 《现代商业》 2010年第24期132-132,131,共2页
自2005年年末到2010年,美国苹果公司的股价上涨了五倍,发展势头猛劲。实际上,在苹果公司背后默默服务的App Store模式形成了本公司的核心竞争力。传统上对苹果公司主要集中于其发展历史、发展战略及领导者的创新意识这几方面的研究,本... 自2005年年末到2010年,美国苹果公司的股价上涨了五倍,发展势头猛劲。实际上,在苹果公司背后默默服务的App Store模式形成了本公司的核心竞争力。传统上对苹果公司主要集中于其发展历史、发展战略及领导者的创新意识这几方面的研究,本文将从产业组织理论的角度,分析App Store在苹果公司企业价值链中的意义,并且从中得到对中国的移动Mobile Market发展的启示。 展开更多
关键词 APP store模式 双边市场 价值链
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应用App Store模式 建设电信企业级应用系统
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作者 黄倚霄 梁勇 《电信科学》 北大核心 2012年第10期132-138,共7页
为了实现信令监测系统"灵活数据采集、统一数据共享、应用快速复制"的目标,避免"烟囱式"信令应用的出现,本文提出利用目前个人应用市场中风行的App Store模式来构建信令监测系统。本文对"烟囱式"系统产... 为了实现信令监测系统"灵活数据采集、统一数据共享、应用快速复制"的目标,避免"烟囱式"信令应用的出现,本文提出利用目前个人应用市场中风行的App Store模式来构建信令监测系统。本文对"烟囱式"系统产生的根源进行了分析,并进一步对采用App Store模式建设企业级应用所具有的优势、实施的关键点和App Store架构与发布共享流程进行了初步的探讨和论证。 展开更多
关键词 APP store 分散建设模式 省集中建设模式 应用分布与共享 信令监测系统
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BI Store——广东移动经分管理模式的探索 被引量:2
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作者 屈强 《移动通信》 2013年第3期60-63,共4页
针对广东移动现有经分系统的不足之处,借鉴App Store的成功理念,提出了BI Store的经分应用商店模式。针对全业务运营时代经分系统的"双中心"定位,阐述了BI Store的功能框架,以及新阶段"两开三共"的经分思路。BI St... 针对广东移动现有经分系统的不足之处,借鉴App Store的成功理念,提出了BI Store的经分应用商店模式。针对全业务运营时代经分系统的"双中心"定位,阐述了BI Store的功能框架,以及新阶段"两开三共"的经分思路。BI Store改善了用户体验,实现了经分需求管理由"计划经济"向"市场经济"的转变,使得基于统一数据模型的经分应用可以快速复制推广。 展开更多
关键词 BI store APP store “双中心”定位 “两开三共”
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App Store中儿童教育软件的现状分析与对策研究 被引量:5
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作者 张乐乐 黄如民 《江苏开放大学学报》 2014年第1期45-49,共5页
数字化时代,移动教育资源为学前儿童的学习提供了崭新的模式。如何将移动教育资源更好地满足儿童的学习体验需求,满足他们的认知、心理特征,是设计开发者关注的话题。按照"评分""价格""人气"的分类标准,A... 数字化时代,移动教育资源为学前儿童的学习提供了崭新的模式。如何将移动教育资源更好地满足儿童的学习体验需求,满足他们的认知、心理特征,是设计开发者关注的话题。按照"评分""价格""人气"的分类标准,App Store儿童教育软件具有界面精美、视觉冲击力强,交互性强、学习趣味浓厚等优点;但也存在着软件资源只强调知识灌输,不注重启发式学习,一定程度上影响了儿童的身心健康成长等问题。对儿童教育软件的设计开发,要注意创设学习情境、寓教于乐;改善应用功能,引导合理使用移动资源。 展开更多
关键词 Appstore 儿童 移动教育软件 现状 对策
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App Store模式:完整的软件产业链生态系统 被引量:4
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作者 项有建 《软件工程师》 2009年第7期44-45,共2页
  自苹果的App Store店开张至今,产业巨头们开设的App Store店已达十家,以App Store店为基础的App Store模式,为业界竞相模仿.在已经开设的App Store店中,有一流的手机厂商,如诺基亚、苹果等;有操作系统的拥有者,如诺基亚、微软和Goo...   自苹果的App Store店开张至今,产业巨头们开设的App Store店已达十家,以App Store店为基础的App Store模式,为业界竞相模仿.在已经开设的App Store店中,有一流的手机厂商,如诺基亚、苹果等;有操作系统的拥有者,如诺基亚、微软和GoogIe等;还有电信运营商,如中国移动等.不过,目前尚未发现有纯独立网站向App Store模式进军.…… 展开更多
关键词 store 软件销售 App store 手机软件 独立网站 手机操作系统 生态系统 产业链
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BI Store——广东移动经营分析管理模式探索 被引量:1
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作者 屈强 《电信技术》 2013年第5期75-78,共4页
BI Store是广东移动首创的经营分析应用商店模式,它借鉴App Store成功理念,变传统经营分析的"浏览器+内容"模式为"应用+内容"模式,支持多种移动智能终端的经营分析应用访问,改善了用户体验。
关键词 BI APP store 移动运营商
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种类繁多的store
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作者 刘艳晖 《中小学英语教学与研究》 北大核心 2003年第6期46-47,共2页
关键词 store 廉价商店 种类 吨计商店 仓库商店 样品展销店 超级市场 方便商店 康保商店 专业商店 百货商店
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Diversity of Stored Grain Insect Pests in the Logone Valley, from Northern Cameroon to Western Chad Republic in Central Africa
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作者 Tamgno Beranger Raoul Ngamo Tinkeu Simon Leonard 《Journal of Agricultural Science and Technology(A)》 2013年第9期724-731,共8页
Insects are major pests of stored grains. In sub Sahara Africa, stored grain insect pests are mainly Coleoptera or Lepidoptera. In the Logone Valley, area covering the Far North Region of Cameroon and South-West of Ch... Insects are major pests of stored grains. In sub Sahara Africa, stored grain insect pests are mainly Coleoptera or Lepidoptera. In the Logone Valley, area covering the Far North Region of Cameroon and South-West of Chad, to our knowledge, the diversity of insect pests noxious to stored products is not established. These beetles and weevils (Insecta:Coleoptera) during their development depreciate food in storage, were able to destroy a whole stock in a very short period of time if no protection of stored food is made. To achieve the diversity of insect pests, inspections of granaries were done in 209 villages of Logone Valley where insect pests were collected and identified. Secondly, the stored grains were sampled in peasant's granaries of Logone Valley and reared in incubators in the Unit of Entomological Research of the University of Ngaound6r6. After their emergence, insects were removed, collected and identified. Their noxious efficiency on stored grains is done by the calculation of the density of each insect pests per gram of grains. This study indicates that 12 species of harmful insects attack cereals and leguminous grains in the Logone Valley during storage. The Bruchids were the main insect pests of legumes. Callosobruchus maculatus was the main pest of legume and attacking mainly cowpeas (34.92 bruchids/g of seed) and peanuts (20.75 bruchids/g of seed). Seven harmful species destroy the cereals. Sitophilus zeamais is the main pest of maize (15.86 weevils/g of maize) and S. oryzae, for sorghum (36.59 weevils/g of maize). Tribolium castaneum were the main secondary pest. T. castaneum infests both cereals and leguminous. This work summarizes the importance and the diversification of stored grain pests in Logone Valley. Knowing the pest diversity is an important step in the strategy to develop a friendly and ecological control method of these harmful insects. 展开更多
关键词 Logone Valley stored grains stored insect pests biodiversity.
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Effects of 2-APB on Store-operated Ca^(2+) Channel Currents of Hepatocytes after Hepatic Ischemia/Reperfusion Injury in Rats
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作者 黄昌州 张宗明 裘法祖 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第1期39-41,共3页
The effects of hepatic ischemia/reperfusion (I/R) injuries on hepatocellular viability and store-operated calcium current (Isoc) in isolated rat hepatocytes and the effects of 2-APB on store-operated calcium current (... The effects of hepatic ischemia/reperfusion (I/R) injuries on hepatocellular viability and store-operated calcium current (Isoc) in isolated rat hepatocytes and the effects of 2-APB on store-operated calcium current (Isoc) in isolated rat hepatocytes after hepatic ischemia/reperfusion injuries were studied. Hepatic ischemia and reperfusion injury model was established and whole cell patch-clamp techniques were used to investigate the effects of 2-APB on Isoc. The results showed that ischemia/reperfusion injuries could significantly reduce hepatocellular viability and further increase Isoc in hepatocytes and 2-APB (20, 40, 60, 80, 100 μmol/L) produced a concentration-dependent decrease of Isoc with IC 50 value of 64.63±10.56 μmol/L (n=8). It was concluded that ischemia/reperfusion injuries could reduce hepatocellular viability, probably through increased Isoc in hepatocytes and 2-APB had a protective effect on ischemia/reperfusion-induced liver injury, probably though inhibiting Isoc. 展开更多
关键词 hepatic ischemia/reperfusion injuries HEPATOCYTES store-operated calcium current store-operated calcium channel calcium channel blockers
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