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脂多糖应激新分子融合蛋白的高表达及纯化
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作者 杜可军 常文辉 +5 位作者 侯立朝 骆文静 刘承利 陈苏民 陈景元 柴玉波 《毒理学杂志》 CAS CSCD 北大核心 2006年第5期291-293,共3页
目的在原核表达系统中表达脂多糖应激新分子编码的蛋白质。方法PCR扩增HlrgcDNA编码区,克隆入表达载体pcTAT中,构建成融合6His的表达载体pcTAT-lrg,转化E.coli BL21(DE3),以IPTG诱导。表达产物用SDS-PAGE及凝胶光密度扫描分析,用Ni-NTA... 目的在原核表达系统中表达脂多糖应激新分子编码的蛋白质。方法PCR扩增HlrgcDNA编码区,克隆入表达载体pcTAT中,构建成融合6His的表达载体pcTAT-lrg,转化E.coli BL21(DE3),以IPTG诱导。表达产物用SDS-PAGE及凝胶光密度扫描分析,用Ni-NTA亲和层析柱纯化。结果经过IPTG诱导4 h,表达出相对分子质量(Mr)约25 000的蛋白,占菌体总蛋白的51%。表达产物为可溶性的,用Ni-NTA亲和层析柱纯化的表达蛋白达到电泳纯。加入培养液中的纯化蛋白,可在30 min内进入HEK293细胞。结论在E.coli中成功地高表达人Lrg融合蛋白,并对其进行初步纯化,为人Lrg功能的研究打下基础。 展开更多
关键词 脂多糖分子 蛋白融合表达 克隆 纯化
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网络新媒体条件下校园安全突发事件应对策略
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作者 翁璇 《佳木斯职业学院学报》 2015年第8期431-,共1页
网络新媒体环境下信息传播更加迅速,互动也更强,给原本就极为敏感的校园安全突发事件的工作的处理带来了新的挑战。如何适应网络新媒体环境下信息传播的特点,避免校园突发事件发生之后传播管理的失控,是当前十分紧迫的工作。在网络新媒... 网络新媒体环境下信息传播更加迅速,互动也更强,给原本就极为敏感的校园安全突发事件的工作的处理带来了新的挑战。如何适应网络新媒体环境下信息传播的特点,避免校园突发事件发生之后传播管理的失控,是当前十分紧迫的工作。在网络新媒体环境下有效应对校园突发事件,需要我们主动出击,充分发挥网络新媒体的优势,并从舆情监控、防范防控及教师队伍建设等方面寻求对策。 展开更多
关键词 网络媒体校园安全突发事件多策略
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新媒介在天津图书馆之应用
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作者 孙立智 《黑龙江史志》 2015年第13期278-279,共2页
应大数据时代的需求,图书馆正面临着由传统向现代的转型。为提高图书馆资源的利用效率,增强图书馆的服务粘性,新媒介的的应用有着不可阻挡之势。网站主页、微信、微博的宣传逐渐成为人们获取知识信息的重要手段。本文就天津图书馆如何... 应大数据时代的需求,图书馆正面临着由传统向现代的转型。为提高图书馆资源的利用效率,增强图书馆的服务粘性,新媒介的的应用有着不可阻挡之势。网站主页、微信、微博的宣传逐渐成为人们获取知识信息的重要手段。本文就天津图书馆如何利用新媒介宣传自己和吸引读者进行了探讨,以期更好的为其发挥社会教育意义提供一点建议。 展开更多
关键词 天津图书馆 媒介 不足与建议
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新媒介在图书馆知识传播中的应用研究
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作者 王晓涵 《江苏科技信息》 2023年第25期29-31,共3页
新媒介的发展改变了人们获取传播信息内容的路径形式,同时极大丰富了图书馆知识传播的内容和形式。据此,文章探讨了新媒介对图书馆知识传播的影响,提出当前图书馆知识传播存在的问题,建议以新媒介助力图书馆资源建设和管理服务,助力图... 新媒介的发展改变了人们获取传播信息内容的路径形式,同时极大丰富了图书馆知识传播的内容和形式。据此,文章探讨了新媒介对图书馆知识传播的影响,提出当前图书馆知识传播存在的问题,建议以新媒介助力图书馆资源建设和管理服务,助力图书馆反馈交流服务,助力图书馆全民阅读文化建设,以期推动图书馆事业高质量发展。 展开更多
关键词 图书馆 知识传播 媒介 模式
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越南《新刊南药神效十科应治》“小儿急惊”探析 被引量:3
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作者 杨丽娜 李几昊 尚力 《中医药文化》 2020年第4期47-53,共7页
越南文化是汉文化圈的重要组成部分,其传统医学受中医药学的影响颇深。通过对越南古医籍《新刊南药神效十科应治》卷九小儿科部分与中国医籍比较,可见其对小儿急惊的病机、症状、治则的认识深受我国宋代钱乙《小儿药证直诀》医学思想的... 越南文化是汉文化圈的重要组成部分,其传统医学受中医药学的影响颇深。通过对越南古医籍《新刊南药神效十科应治》卷九小儿科部分与中国医籍比较,可见其对小儿急惊的病机、症状、治则的认识深受我国宋代钱乙《小儿药证直诀》医学思想的影响,其所载方药主要引自《本草纲目》《普济方》等中国医籍。这种域外接受形式,扩大了中国医药在汉文化圈的影响力,拓展了中医药的应用范围,也促进了中医方药的域外流传和推广。 展开更多
关键词 越南传统医学 《南药神效》 刊南药神效十科治》 小儿急惊 《小儿药证直诀》
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Role of microglial polarization in age-related macular degeneration
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作者 Zhang Yichi Yang Xiuxia +4 位作者 Liu Pingping Liu Mengjie Luo Wenting Liu Yang Yang Chengcheng 《国际眼科杂志》 CAS 2024年第12期1863-1872,共10页
Microglia,originating from primitive macrophages in the yolk sac,serves as both immune system defenders and regulators of homeostasis.These cells exhibit two primary polarization states:conventionally activated(M1)and... Microglia,originating from primitive macrophages in the yolk sac,serves as both immune system defenders and regulators of homeostasis.These cells exhibit two primary polarization states:conventionally activated(M1)and alternatively activated(M2).The polarization of microglia plays a crucial role in influencing inflammatory disorders,metabolic imbalances,and neural degeneration.This process is implicated in various aspects of ocular diseases,especially age-related macular degeneration(AMD),including inflammation,oxidative stress and pathological angiogenesis.The distinct functional phenotypes of microglia impact disease progression and prognosis.Thus,regulating the polarization or functional phenotype of microglia at different stages of AMD holds promise for personalized therapeutic approaches.This comprehensive review outlines the involvement of microglia polarization in both physiological and pathological conditions,emphasizing its relevance in AMD.The discussion underscores the potential of polarization as a foundation for personalized treatment strategies for AMD. 展开更多
关键词 microglia polarization choroidal neovascularization INFLAMMATION oxidative stress macular degeneration
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Microstructure and mechanical properties of AZ61 magnesium alloy parts achieved by thixo-extruding semisolid billets prepared by new SIMA 被引量:13
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作者 姜巨福 王迎 +3 位作者 柳君 曲建俊 杜之明 罗守靖 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期576-585,共10页
New strain induced melt activation(new SIMA) method was employed to prepare high-quality semisolid billet of AZ61 magnesium alloy.Optical microscopy and tensile test were used to study the microstructure and mechani... New strain induced melt activation(new SIMA) method was employed to prepare high-quality semisolid billet of AZ61 magnesium alloy.Optical microscopy and tensile test were used to study the microstructure and mechanical properties of the thixo-extruded component.The results showed that the optimal process parameters for achieving the complete filling status involved the applied pressure of 784 MPa,the pressure holding time of 90 s and the die temperature of 450 ℃.Compared to semisolid isothermal treatment,high mechanical properties such as the tensile strength of 300.5 MPa and elongation of 22% and fine microstructure were obtained in the thixo-extruded parts.With increasing the isothermal temperature and holding time,the tensile strength and elongation were increased firstly and then decreased.When the press pass was increased from 1 to 4,the tensile strength and elongation of the thixo-extruded parts were greatly enhanced and microstructure was refined obviously. 展开更多
关键词 AZ61 magnesium alloy semisolid billets new strain induced melt activation THIXO-EXTRUSION
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An automatic seismic signal detection method based on fourth-order statistics and applications 被引量:2
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作者 刘希强 蔡寅 +4 位作者 赵瑞 曲保安 赵银刚 冯志军 李红 《Applied Geophysics》 SCIE CSCD 2014年第2期128-138,252,共12页
Real-time, automatic, and accurate determination of seismic signals is critical for rapid earthquake reporting and early warning. In this study, we present a correction trigger function(CTF) for automatically detect... Real-time, automatic, and accurate determination of seismic signals is critical for rapid earthquake reporting and early warning. In this study, we present a correction trigger function(CTF) for automatically detecting regional seismic events and a fourth-order statistics algorithm with the Akaike information criterion(AIC) for determining the direct wave phase, based on the differences, or changes, in energy, frequency, and amplitude of the direct P- or S-waves signal and noise. Simulations suggest for that the proposed fourth-order statistics result in high resolution even for weak signal and noise variations at different amplitude, frequency, and polarization characteristics. To improve the precision of establishing the S-waves onset, first a specific segment of P-wave seismograms is selected and the polarization characteristics of the data are obtained. Second, the S-wave seismograms that contained the specific segment of P-wave seismograms are analyzed by S-wave polarization filtering. Finally, the S-wave phase onset times are estimated. The proposed algorithm was used to analyze regional earthquake data from the Shandong Seismic Network. The results suggest that compared with conventional methods, the proposed algorithm greatly decreased false and missed earthquake triggers, and improved the detection precision of direct P- and S-wave phases. 展开更多
关键词 Seismic signal P and S-waves automatic detection correction trigger function
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农村商业银行发起设立村镇银行:孰进孰退? 被引量:2
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作者 杨竹清 《海南金融》 2019年第5期62-70,共9页
村镇银行发展正处在农村金融供给侧改革的巨大机遇期,但在现有环境下也面临遭遇管理难、发展难、盈利难等问题现实难题。农村商业银行发起设立村镇银行具有出身同源、市场经验一致等先天优势,但困扰于实力较弱、知名度不高、人才难聚等... 村镇银行发展正处在农村金融供给侧改革的巨大机遇期,但在现有环境下也面临遭遇管理难、发展难、盈利难等问题现实难题。农村商业银行发起设立村镇银行具有出身同源、市场经验一致等先天优势,但困扰于实力较弱、知名度不高、人才难聚等劣势。本文实证研究发现,农村商业银行设立村镇银行会显著增加管理费用,对盈利能力并无显著影响,在此行业并购重组,重新洗牌的阶段,农村商业银行需要综合更要考量自身条件和村镇银行战略而审慎决策。 展开更多
关键词 村镇银行 发起行 农村商业银行 新应 SWOT
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Fuzzy multiple attribute decision-making model for synergic knowledge innovation in supply chain
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作者 吴冰 赵林度 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期46-50,共5页
The procedure of supply chain development is the process of continuously congregating knowledge and transforming knowledge.First,the precondition of synergic knowledge innovation in the supply chain is narrated.Then t... The procedure of supply chain development is the process of continuously congregating knowledge and transforming knowledge.First,the precondition of synergic knowledge innovation in the supply chain is narrated.Then the characteristics of synergic knowledge innovation in the supply chain are analyzed,including complexity,accumulating and evolving process,and the cooperation of members and network integration.Due to the characteristics of multi-factors and uncertainties of the supply chain system,the fuzzy multi-attribution group decision-making model is introduced to solve the involved problem of synergic knowledge innovation in the supply chain.After elaborating on steps of using the fuzzy multiple attribute decision-making(MADM)model,the procedure of decision making for synergic knowledge innovation in the supply chain is explained from an example in the application of a fuzzy MADM model.The fuzzy MADM model,which amalgamates intuition and resolution decision-making can effectively improve the rationality of decision-making for synergic knowledge innovation in the supply chain. 展开更多
关键词 synergic knowledge innovation supply chain fuzzy multiple attribute decision-making
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Constructivism-based Course Books' Compiling and a New Mode of Teaching
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作者 王玉雯 《Sino-US English Teaching》 2007年第3期1-5,共5页
The paper explores the positive impact of constructivism-based course books compiling and the new mode of teaching, analyzes their effects on helping students improve their integrated English language competence, and ... The paper explores the positive impact of constructivism-based course books compiling and the new mode of teaching, analyzes their effects on helping students improve their integrated English language competence, and pointing out that the development of teaching non-English major graduate students has raised new demands for teaching devices, teaching methodology and new roles of teachers and learners. Therefore, New Century Graduate English Series, as constructivism-based course books, has made some beneficial attempts for the implementation of the new graduate English teaching reauirements. 展开更多
关键词 CONSTRUCTIVISM new mode integrated English language competence New Century GraduateEnglish Series
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Development of a CH4 dehydroaromatization–catalyst regeneration fluidized bed system 被引量:6
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作者 Peng Yan Zhanguo Zhang +5 位作者 Dapeng Li Xu Cheng Xinzhuang Zhang Fan Yang Chuanfeng Huang Xiaoxun Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1928-1936,共9页
A pilot-scale methane dehydroaromatization–H_2regeneration fluidized bed system(MDARS)was developed.In the MDARS,the catalyst circulation between a fluidized bed reactor and a fluidized bed regenerator with the help ... A pilot-scale methane dehydroaromatization–H_2regeneration fluidized bed system(MDARS)was developed.In the MDARS,the catalyst circulation between a fluidized bed reactor and a fluidized bed regenerator with the help of a catalyst feeder allowed methane dehydroaromatization(MDA)and H_2regeneration to be carried out simultaneously,which is good for maintaining a stable MDA catalytic activity.A fixed bed reactor(FB)and a single fluidized bed reactor(SFB)were also used for a comparative study.The experimental results showed that the catalytic activity in the MDARS was more stable than that in the FB and SFB reactors.The effects of some parameters of MDARS on the CH_4conversion and product selectivity were investigated.To verify the feasibility and reliability of the MDARS,an eight-hour long-term test was carried out,which demonstrated that the operation of the MDARS was stable and that the catalytic activity remained stable throughout the entire experimental period. 展开更多
关键词 Methane dehydroaromatization Hydrogen regeneration Fluidized bed reactor PILOT-SCALE Catalyst circulation
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Fabrication and Simulation of Silicon-on-Insulator Structure with Si_3N_4 as a Buried Insulator
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作者 刘奇斌 林青 +2 位作者 刘卫丽 封松林 宋志棠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1722-1726,共5页
In order to minimize the self-heating effect of the classic SOI devices,SOI structures with Si3 N4 film as a buried insulator (SOSN) are successfully formed using epitaxial layer transfer technology for the first ti... In order to minimize the self-heating effect of the classic SOI devices,SOI structures with Si3 N4 film as a buried insulator (SOSN) are successfully formed using epitaxial layer transfer technology for the first time. The new SOI structures are investigated with high-resolution cross-sectional transmission electron microscopy and spreading resistance profile. Experiment results show that the buried Si3 N4 layer is amorphous and the new SOI material has good structural and electrical properties. The output current characteristics and temperature distribution are simulated and compared to those of standard SOI MOSFETs. Furthermore, the channel temperature and negative differential resistance are reduced during high-temperature operation, suggesting that SOSN can effectively mitigate the selfheating penalty. The new SOI device has been verified in two-dimensional device simulation and indicated that the new structures can reduce device self-heating and increase drain current of the SOI MOSFET. 展开更多
关键词 Si3 N4 new SOI structures self-heating effects
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Start-up and Performance of a Novel Reactor----Jet Biogas Inter-loop Anaerobic Fluidized Bed 被引量:2
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作者 邓志毅 韦朝海 周秀峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期143-150,共8页
A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed (JBILAFB), was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose w... A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed (JBILAFB), was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose wastewater treatment. With the wastewater recycle ratio of 2.5 : 1, the recycled wastewater with biogas could mix sludge and wastewater in the JBILAFB reactor completely. The start-up of the JBILAFB reactor could be completed in less than 70 d through maintenance of hydraulic retention time (HR^I") and stepwise increase of feed total organic carbon (TOC) concentration. After the start-up, with the volumetric TOC loadings of 14.3 kg·m ^-3·d^-1, the TOC removal ratio, the effluent pH, and the volatile fatty acids (VFA)/alkalinity of the JBILAFB reactor were more than 80%, close to 7.0 and less than 0.4, respectively. Moreover, CH4 was produced at more than 70% of the theoretical value, The reactor exhibited high stability under the condition of high volumetric TOC loading. Sludge granules in the JBILAFB reactor were developed during the start-up and their sizes were enlarged with the stepwise increase of volumetric TOC loadings from 0.8 kg.m^-3.d ^-1 to 14.3 kg.m^-3.d^-1. Granules, an offwhite color and a similar spherical shape, were mainly comprised of global-like bacteria. These had good methanogenic activity and settleability, which were formed probably through adhesion of the bacteria. Some inorganic metal compounds such as Fe, Ca, Mg, Al, etc. were advantageous to the formation of the granules. 展开更多
关键词 anaerobic reactor jet biogas inter-loop anaerobic fluidized bed wastewater treatment START-UP granule sludge
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A new apparatus for investigating stress,deformation and seepage coupling properties of rock fractures 被引量:1
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作者 刘才华 陈从新 《Journal of Central South University》 SCIE EI CAS 2011年第5期1662-1666,共5页
A true triaxial apparatus which is composed of three units was presented.The apparatus allows for investigations on deformation and seepage behaviors of a single rock fracture subjected to lateral stress and normal st... A true triaxial apparatus which is composed of three units was presented.The apparatus allows for investigations on deformation and seepage behaviors of a single rock fracture subjected to lateral stress and normal stress.The first unit has three jacks which can apply loads independently in three orthogonal directions.The second unit is used to supply water inflow,control seepage pressure and measure flow velocity in real time.The third unit is for measuring the normal deformation of rock fractures.Some tests for investigating the normal deformation and seepage behaviors of rock fractures subjected to normal and lateral loads on hard granite specimens with an artificial persistent fracture,were introduced.The results show that both the normal deformation and the hydraulic conductivity are influenced not only by the normal stress but also by the lateral stress.It is also shown that the aperture and the hydraulic conductivity decrease with the increasing normal stress but increase with the increasing lateral stress and both the aperture and the hydraulic conductivity obey exponential relationships with the normal stress and the lateral stress. 展开更多
关键词 true triaxial apparatus rock fractures normal stress lateral stress normal deformation seepage properties hydraulic conductivity
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Spatial Effect of Mineral Resources Exploitation on Urbanization:A Case Study of Tarim River Basin,Xinjiang,China 被引量:4
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作者 LI Xuemei ZHANG Xiaolei +1 位作者 DU Hongru CHU Shaolin 《Chinese Geographical Science》 SCIE CSCD 2012年第5期590-601,共12页
Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used... Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin,Xinjiang,China for the years of 2000,2006 and 2008.The results are as follows:1)There was a spatial correlation of the development of mineral resources industry and the comprehensive level of urbanization in 2006 and 2008,with the spatial concentration trend rising significantly in 2006 and decreasing in 2008.2)The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were relatively stable,and the two patterns showed signs of spatial correlationship.The higher was the degree of the concentration of mineral resources industry,the stronger was its impact on the spatial clustering of urbanization.3)In 2000, mineral resources excavation and processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent regions.However,in 2008,mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the region but also in its neighboring regions.This research demonstrates that the development of mineral resources industry can strongly affect the trends and spatial patterns of urbanization. 展开更多
关键词 mineral resources development URBANIZATION spatial effect Tarim River Basin
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Primary application of a real-time quantitative polymerase chain reaction for the detection of human breast cancer related novel gene-Metadherin expression 被引量:1
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作者 Bing Li Zhaozhe Liu Xiaodong Xie Yakun Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第6期316-320,共5页
Objective:The aim of this study was to detect the expression level of Metadherin (MTDH) in peripheral blood of the breast cancer patients by real-time fluorescence quantitative polymerase chain reaction (PCR),and to e... Objective:The aim of this study was to detect the expression level of Metadherin (MTDH) in peripheral blood of the breast cancer patients by real-time fluorescence quantitative polymerase chain reaction (PCR),and to explore the relationship between expression of Metadherin gene in the patients peripheral blood and the clinic-pathological features in breast cancer. Methods:Real-time fluorescence quantitative polymerase chain reaction was employed to determine the expression level of Metadherin gene in 80 peripheral blood samples of breast cancer patients and healthy donors. Results:The expression of Metadherin gene in breast cancer patients peripheral blood were positive,in which 34 breast cancer patients were highly expressed,accounting for 55.7%,while the expression of Metadherin gene in normal females peripheral blood were negative,there was statistical significance (Ratio = 2.02±0.81,P < 0.05); Ratio of the Metadherin expression in breast cancer patients peripheral blood and the glyceraldehyde-3-phosphate dehydrogenase expression was 1.15 ± 0.36. REST software analysis showed that the expression of Metadherin gene was significantly up-regulated in breast cancer. Conclusion:The SYBR Green I quantitative real-time polymerase chain reaction method can successfully detect the expression level of Metadherin gene. Expression level of Metadherin gene in breast cancer patients peripheral blood is closely related to survival,and it maybe involved in the development of breast cancer and used as an indicator of prognosis. 展开更多
关键词 breast cancer Metadherin (MTDH) real-time fluorescence quantitative polymerase chain reaction (PCR)
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An adaptive ant colony system algorithm for continuous-space optimization problems 被引量:20
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作者 李艳君 吴铁军 《Journal of Zhejiang University Science》 CSCD 2003年第1期40-46,共7页
Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is pr... Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is proposed in this paper to tackle continuous-space optimization problems, using a new objective-function-based heuristic pheromone assignment approach for pheromone update to filtrate solution candidates.Global optimal solutions can be reached more rapidly by self-adjusting the path searching behaviors of the ants according to objective values. The performance of the proposed algorithm is compared with a basic ant colony algorithm and a Square Quadratic Programming approach in solving two benchmark problems with multiple extremes. The results indicated that the efficiency and reliability of the proposed algorithm were greatly improved. 展开更多
关键词 Ant colony algorithm Continuous space optimization Pheromone update strategy
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A Selective Moving Window Partial Least Squares Method and Its Application in Process Modeling 被引量:1
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作者 徐欧官 傅永峰 +1 位作者 苏宏业 李丽娟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期799-804,共6页
A selective moving window partial least squares(SMW-PLS) soft sensor was proposed in this paper and applied to a hydro-isomerization process for on-line estimation of para-xylene(PX) content. Aiming at the high freque... A selective moving window partial least squares(SMW-PLS) soft sensor was proposed in this paper and applied to a hydro-isomerization process for on-line estimation of para-xylene(PX) content. Aiming at the high frequency of model updating in previous recursive PLS methods, a selective updating strategy was developed. The model adaptation is activated once the prediction error is larger than a preset threshold, or the model is kept unchanged.As a result, the frequency of model updating is reduced greatly, while the change of prediction accuracy is minor.The performance of the proposed model is better as compared with that of other PLS-based model. The compromise between prediction accuracy and real-time performance can be obtained by regulating the threshold. The guidelines to determine the model parameters are illustrated. In summary, the proposed SMW-PLS method can deal with the slow time-varying processes effectively. 展开更多
关键词 SMW-PLS Hydro-isomerizafion process Selective updating strategy Soft sensor
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Adaptive Backstepping Sliding Mode Control for Nonlinear Systems with Input Saturation 被引量:5
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作者 ZHANG Hongmei ZHANG Guoshan 《Transactions of Tianjin University》 EI CAS 2012年第1期46-51,共6页
An adaptive backstepping sliding mode control is proposed for a class of uncertain nonlinear systems with input saturation.A command filtered approach is used to prevent input saturation from destroying the adaptive c... An adaptive backstepping sliding mode control is proposed for a class of uncertain nonlinear systems with input saturation.A command filtered approach is used to prevent input saturation from destroying the adaptive capabilities of neural networks (NNs).The control law and adaptive updating laws of NNs are derived in the sense of Lyapunov function,so the stability can be guaranteed even under the input saturation.The proposed control law is robust against the disturbance,and it can also eliminate the impact of input saturation.Simulation results indicate that the proposed controller has a good performance. 展开更多
关键词 nonlinear system input saturation adaptive backstepping control sliding mode control neural network
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