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Oracle 10g数据库系统性能调优 被引量:1
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作者 任淑美 李宁湘 《电脑知识与技术(过刊)》 2013年第6X期3918-3923,共6页
Oracle数据库是当前应用最广泛的大型关系数据库系统之一,其运行性能直接影响整个应用系统的执行效率。通过对影响Oracle 10g数据库系统运行的主要因素如SGA、PGA、磁盘I/O以及磁盘碎片等的分析,提出了使用Oracle 10g提供相关的工具对... Oracle数据库是当前应用最广泛的大型关系数据库系统之一,其运行性能直接影响整个应用系统的执行效率。通过对影响Oracle 10g数据库系统运行的主要因素如SGA、PGA、磁盘I/O以及磁盘碎片等的分析,提出了使用Oracle 10g提供相关的工具对系统进行性能调整和优化。 展开更多
关键词 SGA PGA 磁盘I/O 磁盘碎片 系统性能调
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从“气能调神,神可御气”角度探讨津沽脏腑推拿治疗郁证的理论依据 被引量:5
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作者 张海宁 李华南 +3 位作者 范顺 唐景潇 吴秋君 王金贵 《天津中医药》 CAS 2022年第5期600-603,共4页
神志病的发病率逐年上升,而郁证是临床上较为常见的神志疾病,影响人们正常生活和工作。“气能调神,神可御气”是津沽推拿学术带头人王金贵教授所提出,文章将系统解释其理论内涵,同时进一步分析其对津沽脏腑推拿的指导意义,进而为津沽脏... 神志病的发病率逐年上升,而郁证是临床上较为常见的神志疾病,影响人们正常生活和工作。“气能调神,神可御气”是津沽推拿学术带头人王金贵教授所提出,文章将系统解释其理论内涵,同时进一步分析其对津沽脏腑推拿的指导意义,进而为津沽脏腑推拿治疗神志疾患提供理论支持,也为推拿治疗功能性内科疾病提供治疗新的思路和方法。 展开更多
关键词 能调 神可御气 气街四海理论 津沽脏腑推拿 郁证
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基于数学建模方法的银行核心系统性能调优研究 被引量:2
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作者 秦文劭 《电子技术与软件工程》 2013年第23期219-219,共1页
随着金融企业的快速崛起,银行的核心业务也在不断发展扩大。银行的核心系统是银行为客户提供存款、贷款、支付、结算以及融资等核心服务的业务系统,它是保证银行提供有效服务和产品的核心所在。随着银行业务量的增加,核心的系统也开始... 随着金融企业的快速崛起,银行的核心业务也在不断发展扩大。银行的核心系统是银行为客户提供存款、贷款、支付、结算以及融资等核心服务的业务系统,它是保证银行提供有效服务和产品的核心所在。随着银行业务量的增加,核心的系统也开始浮现各种弊病。银行办公高峰期时,其核心系统效率降低,甚至出现瘫痪的状况。因此,必须采用有效地措施对银行核心业务系统进行优化和改善。银行核心系统的调优工作操作复杂,必须要依据科学的理论和技术。本文主要阐述的是应用数学建模方法调整和改善银行核心业务系统,以提高银行的核心系统运行效率。 展开更多
关键词 银行核心业务系统 数学建模 系统性能调
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开利活塞式制冷压缩机电磁式能调机构工作分析
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作者 刘文利 宋爱华 《制冷》 2012年第4期70-72,共3页
半封闭式制冷压缩机在冷冻设备上使用普遍,为减小压缩机启动时对电网电压的波动和运行时的节能,半封闭活塞式制冷压缩机常利用能量调节机构来实现机器的上载与卸载,本文以开利06E半封闭活塞式制冷压缩机为例,主要介绍电磁式能量调节机... 半封闭式制冷压缩机在冷冻设备上使用普遍,为减小压缩机启动时对电网电压的波动和运行时的节能,半封闭活塞式制冷压缩机常利用能量调节机构来实现机器的上载与卸载,本文以开利06E半封闭活塞式制冷压缩机为例,主要介绍电磁式能量调节机构的结构与工作原理。 展开更多
关键词 制冷压缩机 电磁式 能调机构 上载 卸载
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综合型调度通信系统在梅钢能调中心的应用
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作者 陈慧芬 《梅山科技》 2007年第B09期1-4,共4页
针对梅钢能源部调度中心能源调度的特点,说明配置综合型的调度通信系统的必要性。简要介绍了能调中心的调度通信系统的网络结构、硬件配置及系统功能,阐述了该系统的具体实现,提高了调度通信系统的兼容性和可靠性。
关键词 能调中心 通信系统 系统结构 系统功能
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基于蓄能调峰系统设计与设备选型研究
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作者 井花蓓 刘耀鑫 +1 位作者 尹莉钧 何深宇 《沈阳工程学院学报(自然科学版)》 2021年第3期24-28,共5页
机组在冬季进行调峰时,由于供暖出力,导致发电负荷无法降低。对此,以某热电厂为例,采用电极蒸汽锅炉蓄能调峰的原理,设计了增设电极锅炉和蓄热水罐的供暖系统,利用负荷分析结果对设备进行选型,并通过计算确定了该方案为电厂带来的最佳... 机组在冬季进行调峰时,由于供暖出力,导致发电负荷无法降低。对此,以某热电厂为例,采用电极蒸汽锅炉蓄能调峰的原理,设计了增设电极锅炉和蓄热水罐的供暖系统,利用负荷分析结果对设备进行选型,并通过计算确定了该方案为电厂带来的最佳经济效益,实现了发电与供热之间的平衡,对同类蓄能调峰改造项目具有一定的借鉴意义。 展开更多
关键词 电极蒸汽锅炉 蓄热水罐 能调 负荷分析
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关于西部地区地方财政能力调研报告 被引量:5
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作者 刘尚希 +4 位作者 王志刚 程瑜 梁季 樊轶侠 武靖州 《财政科学》 2018年第2期5-19,共15页
本报告在考察调研省份地方财政收入能力特征的基础上,分析了目前西部地方财政收入能力建设存在的问题和成因,据此提出应对之策。报告认为,西部地区财政能力建设的主要问题包括:(1)经济发展的"资源型"特征大大增加了财政收入... 本报告在考察调研省份地方财政收入能力特征的基础上,分析了目前西部地方财政收入能力建设存在的问题和成因,据此提出应对之策。报告认为,西部地区财政能力建设的主要问题包括:(1)经济发展的"资源型"特征大大增加了财政收入的不确定性和波动性,增加了地方财政的运行风险;(2)地方财政收入高度依赖于投资(尤其是与政府相关的投资项目),限制了地方财政可持续发展能力;(3)营改增后税源与税收分离问题更加突出,地方财政能力的"马太效应"愈发明显。基于财政能力影响因素,提出如下应对之策:(1)让市场在经济发展中发挥决定性作用,构筑地方财政收入能力提升之基;(2)扩大"消费"类税基,弥补西部地区"生产"的不足;(3)完善地方税体系。 展开更多
关键词 地方财政能力 西部地区 消费类税基
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热敏变色纺织材料的研究进展 被引量:2
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作者 楼焕 刘茜 《针织工业》 北大核心 2024年第2期83-88,共6页
热敏变色纺织品个性化与时尚感强,能实现色彩动态变化,具有良好的功能实用性,可提高产品附加值。为适应纺织领域对热敏变色材料的要求,微胶囊技术常应用于热敏变色纺织材料的开发。文中总结目前热敏变色纺织材料的加工方法,对现有国内... 热敏变色纺织品个性化与时尚感强,能实现色彩动态变化,具有良好的功能实用性,可提高产品附加值。为适应纺织领域对热敏变色材料的要求,微胶囊技术常应用于热敏变色纺织材料的开发。文中总结目前热敏变色纺织材料的加工方法,对现有国内外研究者对热敏变色纺织材料的制备进行归纳总结,得出热敏变色微胶囊技术广泛用于纺织领域,主要使用印花法和后整理法加工得到热敏变色纺织材料;热敏变色纺织材料的色谱拓展是目前研究的新方向;结合其他功能整理或功能材料,可实现热敏变色纺织品的多功能化。 展开更多
关键词 热敏变色微胶囊 印花法 后整理法 色谱拓展 多功能纺织品 相变储能调
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Performance analysis of three-stage liquid desiccant deep dehumidification processor driven by heat pump 被引量:2
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作者 张海强 刘晓华 江亿 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期217-221,共5页
A new type of a heat pump driven three-stage lithium bromide liquid desiccant deep dehumidification processor is presented,which can dehumidify the outdoor humid air to a rather dry state,even when there is no availab... A new type of a heat pump driven three-stage lithium bromide liquid desiccant deep dehumidification processor is presented,which can dehumidify the outdoor humid air to a rather dry state,even when there is no available indoor exhaust air.The test results show that with an outdoor air temperature of 28 to 31 ℃ and an outdoor air humidity ratio of 11 to 14 g/kg,the supply air temperature and the supply air humidity ratio are 1.6 to 2.6 ℃ and 2.6 to 3.0 g/kg,respectively,and the coefficient of performance(COP)of the processor is 1.8.During the test,a liquid pipeline link problem leading to mixture losses of hot and cold liquid desiccants is found.These pipelines are modified.Then,the performance of the modified processor is investigated.And the experimental results show that with an outdoor air temperature of 25 to 32 ℃ and an outdoor air humidity ratio of 18 to 21 g/kg,the supply air temperature and the supply air humidity ratio are 3.2 to 4.0 ℃ and 3.4 to 3.6 g/kg,respectively,and the COP is 2.8.Finally,a mathematical model of the processor is established.The comparison of the simulation results and the test results of the processor exhibits that the pipeline modification improves the performance by about 20%. 展开更多
关键词 deep dehumidification liquid desiccant performance test AIR-CONDITIONING
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Analysis and Modeling of the Central Air-Conditioning System in Intelligent Buildings 被引量:6
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作者 郭巧 徐庆伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期295-297,共3页
The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed ... The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods. 展开更多
关键词 intelligent building analysis and modeling central air conditioning energy saving
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Developmental Regulation and Biological Functions of Root Border Cells in Higher Plants 被引量:12
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作者 潘建伟 朱睦元 +1 位作者 彭华正 王利琳 《Acta Botanica Sinica》 CSCD 2002年第1期1-8,共8页
Root border cells, previously referred to as sloughed root cap cells, is a special cell population which separates in large numbers from the periphery of the root cap and accumulates in the root tip. Recent evidence r... Root border cells, previously referred to as sloughed root cap cells, is a special cell population which separates in large numbers from the periphery of the root cap and accumulates in the root tip. Recent evidence reveals that border cells, whose development is regulated by endogenous and exogenous signals, are biologically viable in the majority of higher plant species. As soon as border cells detach from root cap periphery, their metabolic activity dramatically increases in accordance with a differential gene expression from that in root cap cells. Recently, PsUGT1 and RCPME1, relevant to the early and late stage of border cell development, respectively, have been cloned and functionally identified. Border cells can synthesize specially and export a diverse array of chemicals including anthocyanins, antibiotics, special enzymes and other substances, that either inhibit or promote the growth of other entities in rhizosphere such as bacteria, fungi, viruses, and nematodes, and also antagonize some toxic chemicals around the root tip in soil such as aluminum toxicity. Therefore, there are multiple biological roles played by border cells during plant growth and development. 展开更多
关键词 border cells DEVELOPMENT FUNCTION PLANT STRESS
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Oil-Film Clutch in Soft-Start of Belt Conveyor 被引量:3
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作者 周满山 魏宸官 +1 位作者 于岩 张媛 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期142-145,共4页
The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch... The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch, equations that are used to decide the lubricating oil flow and the number of oil films (i.e. the number of rotating and stationary plates) are deduced theoretically. Also key parameters are provided for the design of the hydraulic system. All these together provide the theoretical basis for the soft start design of the belt conveyor and references for the application of the oil film clutch in similar fields. 展开更多
关键词 belt conveyor soft start oil film clutch lubricating theory
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Optimum Energy Management of the Central Air-Conditioning System in Intelligent Buildings
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作者 郭巧 徐庆伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期298-301,共4页
An optimum energy saving scheduling strategy of the central air conditioning system in an intelligent building (IB) was proposed. Based on the system analysis a set of models of the central air conditioning system w... An optimum energy saving scheduling strategy of the central air conditioning system in an intelligent building (IB) was proposed. Based on the system analysis a set of models of the central air conditioning system was established. The periodically autoregressive models (PARM) based on genetic algorithms (GA) were used to predict the next day’s cold load. The improved genetic algorithms (IGA) with stochastic real number coding were used to finish the optimum energy saving scheduling of the system. The simulation results for the building of the Liangmahe Plaza show that the proposed strategy can save energy up to about 24 5%. 展开更多
关键词 intelligent building genetic algorithms central air conditioning energy saving
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A distributed algorithm for signal coordination of multiple agents with embedded platoon dispersion model
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作者 别一鸣 王殿海 +1 位作者 马东方 朱自博 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期311-315,共5页
In order to reduce average arterial vehicle delay, a novel distributed and coordinated traffic control algorithm is developed using the multiple agent system and the reinforce learning (RL). The RL is used to minimi... In order to reduce average arterial vehicle delay, a novel distributed and coordinated traffic control algorithm is developed using the multiple agent system and the reinforce learning (RL). The RL is used to minimize average delay of arterial vehicles by training the interaction ability between agents and exterior environments. The Robertson platoon dispersion model is embedded in the RL algorithm to precisely predict platoon movements on arteries and then the reward function is developed based on the dispersion model and delay equations cited by HCM2000. The performance of the algorithm is evaluated in a Matlab environment and comparisons between the algorithm and the conventional coordination algorithm are conducted in three different traffic load scenarios. Results show that the proposed algorithm outperforms the conventional algorithm in all the scenarios. Moreover, with the increase in saturation degree, the performance is improved more significantly. The results verify the feasibility and efficiency of the established algorithm. 展开更多
关键词 multiple agents signal coordination reinforce learning platoon dispersion model
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A Review on the Biological Characteristics and Secretory Functions of Adipose-derived Mesenchymal Stem Cells 被引量:2
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作者 刘雪婷 支晓亮 +2 位作者 白春雨 张明海 关伟军 《Agricultural Science & Technology》 CAS 2016年第6期1331-1335,共5页
Adipose-derived mesenchymal stem cells (ADSCs) can be largely and easily obtained from a wide range of sources. Moreover, they have self-renewal ability, multi-differentiation potential, and an important role in imm... Adipose-derived mesenchymal stem cells (ADSCs) can be largely and easily obtained from a wide range of sources. Moreover, they have self-renewal ability, multi-differentiation potential, and an important role in immune regulation. They can secrete a variety of cytokines to regulate the in vivo micro-environment. Therefore, ADSCs are the ideal seed ceils for stem ceils application. This paper reviews the location, isolation, surface markers, proliferation, differentiation and other biological characteristics of ADSCs, as well as their secretory function and relative researches. ADSCs are expected to become excellent seed cells for cell therapy and tissue engineering through in-depth studies. 展开更多
关键词 Adipose-derived mesenchymal stem cell Surface markers Proliteration and differentiation Immune regulation SECRETION
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Performance enhancement of IEEE 802.11 distributed coordination function for MANET
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作者 翟旭平 毕光国 徐平平 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期418-422,共5页
The medium access control (MAC) issue was discussed in mobile Ad Hoc networks (MANETs). Based on the IEEE 802.11 MAC protocol, this paper proposed two schemes, the forward-packet-first (FPF) scheme based on the adapti... The medium access control (MAC) issue was discussed in mobile Ad Hoc networks (MANETs). Based on the IEEE 802.11 MAC protocol, this paper proposed two schemes, the forward-packet-first (FPF) scheme based on the adaptive backoff contention window and multihop forward chain transmission by invitation (MFCTI) scheme. In the FPF scheme, the contention window was adjusted adaptively according to the traffic priority. Route information and the broadcast characteristic of radio were utilized in MFCTI scheme. The performance of these schemes was studied in multihop environments by simulations. The results showed that the proposed schemes could improve the network throughput, reduce the end-to-end average delay, and mitigate local congestion effectively. Another attractive feature was that the schemes could be implemented with minor modifications to the IEEE 802.11 MAC. 展开更多
关键词 Adaptive systems Packet networks Radio broadcasting ROUTERS
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Advances in the Regulation of RpoS Protein Expression and Its Function in Bacteria 被引量:2
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作者 王淑娴 李天保 +4 位作者 叶海斌 魏鉴腾 王勇强 刁菁 杨秀生 《Agricultural Science & Technology》 CAS 2012年第6期1215-1221,1225,共8页
RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulat... RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulated at three levels: transcription level, translation level and post-translational level. Environmental stress enters bacterial cells through signal transduction and leads to a series of variations in microenvironment, thereby causing changes of regulator and controlling its levels based on the direct and indirect interaction between regulator and RpoS protein. In addition, RpoS protein has played special roles in bacteria, therefore the changes of RpoS protein levels will lead to variations in expression levels of a large number of genes, thereby causing variations of bacterial response to different environmental stress and changes of certain characteristics of bacteria, which provides a new strategy for the control of bacterial diseases in the future. This paper reviewed the recent progress on the regulation of RpoS protein expression and its function in several common bacteria. Due to the functional complexity of RpoS protein, there are still a lot of unknown functions to be further identified. 展开更多
关键词 RpoS or σ S rpoS gene Expression regulation Environmental stress RpoS function
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蓄能技术在热电联产机组中的应用
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作者 付亚州 《电力系统装备》 2020年第7期39-41,共3页
本文结合蓄能调峰技术在佳木斯热电厂的应用,介绍了蓄能系统的选型过程和蓄能调峰系统的接入方式,对蓄能调峰技术在同类型热电联产机组中的应用具有一定的指导意义.
关键词 能调 蓄能罐 应用
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A NOTE ON CONDITIONAL IMPLICATION
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作者 朱朝晖 李斌 +1 位作者 陈世福 朱梧槚 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第1期41-46,共6页
It is well known that there exists a tight connection between nonmonotonic reasoning and conditional implication. Many researchers have investigated it from various angles. Among th em, C.Boutilier and P.Lamarre hav... It is well known that there exists a tight connection between nonmonotonic reasoning and conditional implication. Many researchers have investigated it from various angles. Among th em, C.Boutilier and P.Lamarre have shown that some conditional implication may b e regarded as the homology of different nonmonotonic consequence relations. In t his paper, based on the plausibility space introduced by Friedman and Halpern, w e characterize the condition logic in which conditional implication is nonmonoto nic, and this result characterizes the conditional implication which may be rega rded as the corresponding object in Meta language for nonmonotonic inference rel ations. 展开更多
关键词 commonsense reasoning artifical intelligence knowledge representation nonmonotonic logic conditiona l logic
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TGF-β1-promoted epithelial-to-mesenchymal transformation and cell adhesion contribute to TGF-β1-enhanced cell migration in SMMC-7721 cells 被引量:30
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作者 ZHENXU MINXIONGSHEN +2 位作者 DONGZHUMA LIYINGWANG XILIANGZHA 《Cell Research》 SCIE CAS CSCD 2003年第5期343-350,共8页
Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses... Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses its growth-inhibitory and apoptosis-inducing effects, but stimulates the metastatic capacity of tumor cells. It is currently little known about TGF-β1-promoted cell migration in hepatocellular carcinoma (HCC) cells, let alone its mechanism. In this study, we found that TGF-β1 lost its tumor-suppressive effects, but significantly stimulated cell migration in SMMC-7721 human HCC cells. By FACS and Western blot analysis, we observed that TGF-β1 enhanced the expression of α5β1 integrin obviously, and subsequently stimulated cell adhesion onto fibronectin (Fn). Furthermore, we observed that TGF-β1 could also promote SMMC-7721 cells adhesion onto laminin (Ln). Our data also provided evidences that TGF-β1 induced epithelial-to-mesenchymal transformation (EMT) in SMMC-7721 cells. First, SMMC-7721 cells clearly switched to the spindle shape morphology after TGF-β1 treatment. Furthermore, TGF-β1 induced the down-regulation of E-cadherin and the nuclear translocation of β-catenin. These results indicated that TGF-β1-promoted cell adhesion and TGF-β1-induced epithelial-to-mesenchymal transformation might be both responsible for TGF-β1-enhanced cell migration. 展开更多
关键词 TGF-Β1 cell migration epitheIial-to-mesenchymal transformation α5β1 integrin.
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