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基于酵母双杂交技术对与纳尔逊海湾正呼肠孤病毒σNS相互作用宿主蛋白的筛选
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作者 孙绿茵 马竹萍 +2 位作者 李润林 李永刚 陶晓莉 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期1313-1321,共9页
目的:探讨小鼠成纤维L929细胞中与纳尔逊海湾正呼肠孤病毒(NBV)σNS蛋白相互作用(互作)的宿主蛋白,阐明宿主蛋白对病毒复制的影响。方法:构建表达σNS蛋白的诱饵质粒pGBKT7-S3,采用测序技术验证诱饵质粒在Y2H酵母细胞中的准确表达。将pG... 目的:探讨小鼠成纤维L929细胞中与纳尔逊海湾正呼肠孤病毒(NBV)σNS蛋白相互作用(互作)的宿主蛋白,阐明宿主蛋白对病毒复制的影响。方法:构建表达σNS蛋白的诱饵质粒pGBKT7-S3,采用测序技术验证诱饵质粒在Y2H酵母细胞中的准确表达。将pGBKT7-S3和pGADT7质粒分别和共同转化至Y2HGold酵母细胞中,涂布于固体培养基进行培养,观察菌落生长情况,确认σNS蛋白对酵母细胞无毒性,不能自行激活报告基因。诱饵质粒pGBKT7-S3与小鼠成纤维L929细胞的cDNA文库进行杂交,对编码互作蛋白的阳性克隆进行质粒抽提,阳性测序结果通过Uniprot数据库检索筛选得到与NBVσNS互作的蛋白。对互作蛋白进行基因本体论(GO)功能富集分析、京都基因和基因组百科全书(KEGG)信号通路富集分析和STRING生物信息学分析。结果:成功筛选出61个阳性克隆。DNA测序分析和BLAST比对分析去除23个未匹配到数据库和测序基本相同的阳性克隆。阳性测序结果通过Uniprot数据库检索筛选得到38个与NBVσNS互作的蛋白,31个蛋白参与细胞生物过程,36个蛋白是细胞解剖成分,31个蛋白具有结合功能,5个蛋白是线粒体呼吸链组成部分,7个蛋白是核糖体蛋白和核糖体大小亚基的组成部分,2个蛋白参与铁代谢稳态。GO功能富集分析,互作蛋白参与的生物过程(BP)富集在细胞过程、代谢过程、生物学调节、定位和对刺激的反应等;细胞组分主要是细胞解剖成分和含蛋白复合物;分子功能集中在结合、催化活性、结构分子活性和转运活性等方面。KEGG信号通路富集分析,蛋白在遗传信息处理途径的翻译、折叠、分类和降解信号通路中高度富集,在机体系统中主要与消化系统有关联;与多种病毒性传染病和癌症有关联。STRING分析,互作蛋白涉及核糖体蛋白类、蛋白修饰类、代谢类和免疫蛋白类等功能蛋白。结结论论:成功筛选出与NBVσNS蛋白互作的蛋白,宿主蛋白在病毒复制中具有重要作用。 展开更多
关键词 纳尔逊海湾正呼肠孤病毒 酵母双杂交实验 σNS蛋白 蛋白互相作用 生物信息学
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蛋白质与酸性染料相互作用的分光光度研究 被引量:14
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作者 罗宗铭 张焜 +1 位作者 崔英德 董飞燕 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2001年第2期251-253,共3页
分别在酸性和碱性介质研究了铬天青S(CAS) ,溴甲酚绿 (BCG) ,溴邻苯三酚红 (BPR)和甲基百里酚蓝 (MTB)与蛋白质结合的光度性质。在 pH 3 8~ 4 0 ,蛋白质使CAS和BCG的吸光度降低 ,在 pH 3 8和10 8,蛋白质分别使BPR和MTB最大吸收波长红... 分别在酸性和碱性介质研究了铬天青S(CAS) ,溴甲酚绿 (BCG) ,溴邻苯三酚红 (BPR)和甲基百里酚蓝 (MTB)与蛋白质结合的光度性质。在 pH 3 8~ 4 0 ,蛋白质使CAS和BCG的吸光度降低 ,在 pH 3 8和10 8,蛋白质分别使BPR和MTB最大吸收波长红移 10和 2 0nm ,并使染料吸光度增大。无论染料吸光度降低或增大 ,均与蛋白质浓度在一定浓度范围内成正比。初步讨论了蛋白质与染料作用的机理。 展开更多
关键词 蛋白质 酸性染料 互相作用机理 分光光度法 吸光度 浓度
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汉语歇后语前、后语节相互作用关系研究 被引量:4
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作者 马利军 张积家 《苏州大学学报(教育科学版)》 2016年第3期86-95,共10页
前、后语节的语义关系是歇后语区别于其它语汇的重要本质。实验1和2通过启动范式探讨喻意型和谐音型歇后语前、后语节互相作用的关系。结果发现,对喻意型歇后语和未呈现同音线索的谐音型歇后语,后一语节对前一语节的启动量大于相反方向... 前、后语节的语义关系是歇后语区别于其它语汇的重要本质。实验1和2通过启动范式探讨喻意型和谐音型歇后语前、后语节互相作用的关系。结果发现,对喻意型歇后语和未呈现同音线索的谐音型歇后语,后一语节对前一语节的启动量大于相反方向的启动量。在呈现同音线索的条件下,谐音型歇后语后一语节对前一语节出现负启动现象。实验结果证实歇后语后一语节的语义单一、明了,语义确定作用明显。同时,实验3通过眼动技术探讨在前、后语节语义一致或不一致条件下,歇后语前、后语节加工的时间差异,结果发现前一语节加工需要更多的时间,但后一语节的语义是歇后语理解的关键。结合3个实验的结果可知,歇后语后一语节是源,前一语节是流;歇后语创作和理解均基于前、后语节的语义一致性;同时,前、后语节的创作更多基于语用原则。 展开更多
关键词 歇后语 前、后语节 互相作用 关系 语用原则
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低温胁迫对处于不同水分状态柑桔光合作用的影响 被引量:8
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作者 张放 唐晓蕴 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2001年第4期393-397,共5页
研究了低温胁迫对处于不同水分条件下柑桔光合作用的影响规律 .结果表明 ,低温胁迫对柑桔光合作用的影响与土壤水分状态关系密切 .对于正常供水的植株 ,低温能明显降低 Pn和 Gs.Ci/ Ca的比值升高表明低温主要抑制了叶肉细胞的光合能力 ... 研究了低温胁迫对处于不同水分条件下柑桔光合作用的影响规律 .结果表明 ,低温胁迫对柑桔光合作用的影响与土壤水分状态关系密切 .对于正常供水的植株 ,低温能明显降低 Pn和 Gs.Ci/ Ca的比值升高表明低温主要抑制了叶肉细胞的光合能力 ;而适宜的根部温度能够提高受低温影响叶片的 Pn和 Gs,但从酶的大幅度增加可知 ,这是以散失大量水分为代价的 .而对于受水分胁迫的植株 ,一方面低温对 Pn的抑制作用不明显 .即水分胁迫使柑桔对低温胁迫变得不敏感 ;另一方面 ,与仅受低温影响的植株相比 ,提高根温反而使 Pn下降幅度更大 ,但 Gs和酶却增加 。 展开更多
关键词 柑桔 光合作用 低温协迫 水分 互相作用
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地震作用下可液化土层水平受荷桩基力学响应分析 被引量:5
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作者 高新文 《地震工程与工程振动》 CSCD 北大核心 2016年第3期102-110,共9页
地震作用下可液化场地桩土相互作用研究是解决可液化场地桩基抗震问题的有效途径。本文基于p-y曲线方法,通过Cu因子法建立地震过程中可液化地层的典型p-y曲线模型。结合有限差分原理,建立了水平受荷单桩在地震作用下的水平附加响应计算... 地震作用下可液化场地桩土相互作用研究是解决可液化场地桩基抗震问题的有效途径。本文基于p-y曲线方法,通过Cu因子法建立地震过程中可液化地层的典型p-y曲线模型。结合有限差分原理,建立了水平受荷单桩在地震作用下的水平附加响应计算方法,通过实例验证了该计算方法的合理性。最后控制变量,利用该方法进行了一系列的参数分析。研究结果表明:可液化地层厚度、桩基受荷水平和液化程度对于地震液化引起的受荷桩基水平附加响应的影响都较为显著;桩身附加挠度和附加弯矩均随着受荷载水平或液化程度的增大而呈非线性形式增大,且受荷水平或液化程度越高,增长速率越大。 展开更多
关键词 地震 可液化地层 桩土互相作用 P-Y曲线 附加响应
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政府间相互作用实证分析模型述评 被引量:1
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作者 雷晓康 《西北农林科技大学学报(社会科学版)》 2004年第4期75-80,共6页
从1993年Case、Rosen和Hines的研究开始,经济学家利用博弈理论及空间计量经济学的分析方法对政府间的相互作用、相互竞争的程度进行了大量的实证研究,总结出多种实证模式。这些研究一方面极大地丰富了公共经济学中关于政府竞争的理论,... 从1993年Case、Rosen和Hines的研究开始,经济学家利用博弈理论及空间计量经济学的分析方法对政府间的相互作用、相互竞争的程度进行了大量的实证研究,总结出多种实证模式。这些研究一方面极大地丰富了公共经济学中关于政府竞争的理论,另一方面,也有利于各级政府进行有效决策,为社会的发展提供各种必要的公共物品。 展开更多
关键词 政府 竞争 互相作用 实证模型
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Numerical Modeling of Ship-Ice-Water Interaction for Freerunning Ships in Pack Ice
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作者 ZOU Ming ZOU Zao−jian +1 位作者 ZOU Lu ZHU Sheng−tao 《船舶力学》 北大核心 2025年第6期878-887,共10页
Ice-going ships play a crucial role in polar transportation and resource extraction.Different from the existing modeling approach which assumes that ships remain stationary,dynamic overset grid technology and DFBI(Dyn... Ice-going ships play a crucial role in polar transportation and resource extraction.Different from the existing modeling approach which assumes that ships remain stationary,dynamic overset grid technology and DFBI(Dynamic Fluid-Body Interaction)method are employed in this paper to enable the free-running motion of the ship in modeling.A numerical model capable of simulating a ship navigating through pack ice area is proposed,which uses Computational Fluid Dynamics(CFD)method to solve the flow field and applies the Discrete Element Method(DEM)to simulate ship-ice and ice-ice interactions.Besides,the proposed high-precision method for generating pack ice area can be used in conjunction with the proposed numerical model.By comparing the numerical results with the available model test data and experimental observations,the effectiveness of the numerical model is validated,demonstrating its strong capability of predicting resistance and simulating ship navigation in pack ice,as well as its significant potential and applicability for further studies. 展开更多
关键词 pack ice ship-ice-water interaction CFD-DEM dynamic overset grid technology ship resistance
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Research progress on metal-support interactions over Ni-based catalysts for CH_(4)-CO_(2)reforming reaction
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作者 SUN Kai JIANG Jianfei +4 位作者 LIU Zixuan GENG Shiqi LIU Zhenmin YANG Jiaqian LI Shasha 《燃料化学学报(中英文)》 北大核心 2025年第4期434-451,共18页
With ongoing global warming and increasing energy demands,the CH_(4)-CO_(2)reforming reaction(dry reforming of methane,DRM)has garnered significant attention as a promising carbon capture and utilization technology.Ni... With ongoing global warming and increasing energy demands,the CH_(4)-CO_(2)reforming reaction(dry reforming of methane,DRM)has garnered significant attention as a promising carbon capture and utilization technology.Nickel-based catalysts are renowned for their outstanding activity and selectivity in this process.The impact of metal-support interaction(MSI),on Ni-based catalyst performance has been extensively researched and debated recently.This paper reviews the recent research progress of MSI on Ni-based catalysts and their characterization and modulation strategies in catalytic reactions.From the perspective of MSI,the effects of different carriers(metal oxides,carbon materials and molecular sieves,etc.)are introduced on the dispersion and surface structure of Ni active metal particles,and the effect of MSI on the activity and stability of DRM reactions on Ni-based catalysts is discussed in detail.Future research should focus on better understanding and controlling MSI to improve the performance and durability of nickel-based catalysts in CH_(4)-CO_(2)reforming,advancing cleaner energy technologies. 展开更多
关键词 CO_(2)utilization CH_(4)-CO_(2)reforming Ni-based catalysts metal-support interactions supports
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Syntheses,crystal structures,and diametrically opposed mechanically-stimulated luminescence response of two Mg(Ⅱ)metal-organic frameworks
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作者 CHEN Yukun FENG Kexin +2 位作者 ZHANG Bolun SONG Wentao ZHANG Jianjun 《无机化学学报》 北大核心 2025年第6期1227-1234,共8页
The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and... The reaction of Mg^(2+)and 5-{1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl}terephthalic acid(H_(2)L)leads to two metal-organic frameworks,[Mg(L)(DMF)_(2)(H_(2)O)_(2)]_(2)·5DMF·2H_(2)O(1)with a 1D structure and[Mg_(2)(L)_(2)(DMSO)_(3)(H_(2)O)](2)with a 2D(4,4)-net structure.Interestingly,the two compounds exhibit distinct luminescent responses to external mechanical stimuli.1 exhibited exceptional resistance mechanical chromic luminescence(RMCL),which can be attributed to the predominant hydrogen bonds and the presence of high-boiling-point solvent molecules within its structure.2 had a reversible MCL property,which can be attributed to the dominantπ-πweak interactions,coupled with the reversible destruction/restoration of its crystallinity under grinding/fumigation.CCDC:2410963,1;2410964,2. 展开更多
关键词 metal-organic framework crystal structure mechanical chromic luminescence resistance mechanical chromic luminescence weak interaction
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Identification of shared key genes and pathways in osteoarthritis and sarcopenia patients based on bioinformatics analysis
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作者 SUN Yuyan LUO Ziyu +6 位作者 LING Huixian WU Sha SHEN Hongwei FU Yuanyuan NGO Thainamanh WANG Wen KONG Ying 《中南大学学报(医学版)》 北大核心 2025年第3期430-446,共17页
Objective:Osteoarthritis(OA)and sarcopenia are significant health concerns in the elderly,substantially impacting their daily activities and quality of life.However,the relationship between them remains poorly underst... Objective:Osteoarthritis(OA)and sarcopenia are significant health concerns in the elderly,substantially impacting their daily activities and quality of life.However,the relationship between them remains poorly understood.This study aims to uncover common biomarkers and pathways associated with both OA and sarcopenia.Methods:Gene expression profiles related to OA and sarcopenia were retrieved from the Gene Expression Omnibus(GEO)database.Differentially expressed genes(DEGs)between disease and control groups were identified using R software.Common DEGs were extracted via Venn diagram analysis.Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were conducted to identify biological processes and pathways associated with shared DEGs.Protein-protein interaction(PPI)networks were constructed,and candidate hub genes were ranked using the maximal clique centrality(MCC)algorithm.Further validation of hub gene expression was performed using 2 independent datasets.Receiver operating characteristic(ROC)curve analysis was used to evaluate the predictive value of key genes for OA and sarcopenia.Mouse models of OA and sarcopenia were established.Hematoxylin-eosin and Safranin O/Fast Green staining were used to validate the OA model.The sarcopenia model was validated via rotarod testing and quadriceps muscle mass measurement.Real-time reverse transcription PCR(real-time RT-PCR)was employed to assess the mRNA expression levels of candidate key genes in both models.Gene set enrichment analysis(GSEA)was conducted to identify pathways associated with the selected shared key genes in both diseases.Results:A total of 89 common DEGs were identified in the gene expression profiles of OA and sarcopenia,including 76 upregulated and 13 downregulated genes.These 89 DEGs were significantly enriched in protein digestion and absorption,the PI3K-Akt signaling pathway,and extracellular matrix-receptor interaction.PPI network analysis and MCC algorithm analysis of the 89 common DEGs identified the top 17 candidate hub genes.Based on the differential expression analysis of these 17 candidate hub genes in the validation datasets,AEBP1 and COL8A2 were ultimately selected as the common key genes for both diseases,both of which showed a significant upregulation trend in the disease groups(all P<0.05).The value of area under the curve(AUC)for AEBP1 and COL8A2 in the OA and sarcopenia datasets were all greater than 0.7,indicating that both genes have potential value in predicting OA and sarcopenia.Real-time RT-PCR results showed that the mRNA expression levels of AEBP1 and COL8A2 were significantly upregulated in the disease groups(all P<0.05),consistent with the results observed in the bioinformatics analysis.GSEA revealed that AEBP1 and COL8A2 were closely related to extracellular matrix-receptor interaction,ribosome,and oxidative phosphorylation in OA and sarcopenia.Conclusion:AEBP1 and COL8A2 have the potential to serve as common biomarkers for OA and sarcopenia.The extracellular matrix-receptor interaction pathway may represent a potential target for the prevention and treatment of both OA and sarcopenia. 展开更多
关键词 OSTEOARTHRITIS SARCOPENIA BIOINFORMATICS extracellular matrix-receptor interaction key genes
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Metformin Induces Non-small Cell Lung Cancer Cells Apoptosis Depending on AMPK-mediated RIP1 Downregulation
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作者 LI Min SHI Shao-Qing ZHENG Yuan-Yuan 《中国生物化学与分子生物学报》 北大核心 2025年第4期551-559,共9页
The incidence and mortality rate of lung cancer rank among the highest worldwide,severely endangering human health and life.Metformin,an anti-diabetes drug,has been shown to elicit anticancer activities in various tum... The incidence and mortality rate of lung cancer rank among the highest worldwide,severely endangering human health and life.Metformin,an anti-diabetes drug,has been shown to elicit anticancer activities in various tumors.However,its underlying mechanisms remain elusive.In this work,we explore the role of receptor-interacting protein 1(RIP1)which plays a crucial role in the process of cell death,in metformin-induced anticancer activities in lung cancer.Metformin inhibits lung cancer cell proliferation in a dose-dependent manner and promotes apoptotic cell death,as evidenced by metformin-induced PARP and caspase cleavage.Furthermore,the pan-caspase inhibitor z-VAD-fmk reverses metformin-induced cell death.Western blot and qPCR results suggest that metformin markedly downregulates RIP1 expression without affecting its mRNA and ubiquitination levels(0 vs 80 mmol/L,100%vs 20%,100%vs 15%).Additionally,co-immunoprecipitation and immunofluorescence results reveal that metformin may suppress RIP1 expression in an Hsp70-dependent manner,as metformin promotes Hsp70 degradation,and Hsp70 endogenously interacts with RIP1.Subsequent CCK-8,flow cytometry,and Western blot analyses suggest that metformin decreases Hsp70/RIP1 expression through AMPK/PKA/GSK-3βaxis.Consistently,results from a subcutaneous transplant tumor model indicate that metformin retards tumor growth without affecting mouse body weight.Collectively,these data highlight the part of RIP1 in metformin-induced anticancer activities in lung cancer in vitro and in vivo,providing novel strategy for lung cancer administration. 展开更多
关键词 lung cancer METFORMIN receptor-interacting protein 1(RIP1) heatshockprotein70(Hsp70) AMP-activated protein kinas(AMPK)
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Seismic pseudo-static stability analysis of bedding jointed rock slope stability under the interaction of the upper dangerous rock mass and lower stepped slope mass based on acceleration assessment
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作者 LI De-jian XIAO Yu +3 位作者 YANG Yan-song YU Peng-cheng ZHANG Ying-bin ZHAO Lian-heng 《Journal of Central South University》 2025年第7期2619-2637,共19页
In the practical slope engineering,the stability of lower sliding mass(region A)with back tensile cracks of the jointed rock slope attracts more attentions,but the upper rock mass(region B)may also be unstable.Therefo... In the practical slope engineering,the stability of lower sliding mass(region A)with back tensile cracks of the jointed rock slope attracts more attentions,but the upper rock mass(region B)may also be unstable.Therefore,in this study,based on the stepped failure mode of bedding jointed rock slopes,considering the influence of the upper rock mass on the lower stepped sliding mass,the improved failure model for analyzing the interaction force(F_(AB))between two regions is constructed,and the safety factors(F_(S))of two regions and whole region are derived.In addition,this paper proposes a method to determine the existence of F_(AB) using their respective acceleration values(a_(A) and a_(B))when regions A and B are unstable.The influences of key parameters on two regions and the whole region are analyzed.The results show that the variation of the F_(AB) and F_(S) of two regions can be obtained accurately based on the improved failure model.The accuracy of the improved failure model is verified by comparative analysis.The research results can explain the interaction mechanism of two regions and the natural phenomenon of slope failure caused by the development of cracks. 展开更多
关键词 bedding jointed rock slope upper dangerous rock mass stepped sliding interaction mechanism stability analysis
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发热伴血小板减少综合征病毒非结构蛋白的表达和定位及宿主互作蛋白的筛选和分析
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作者 骆丽可 程子文 +3 位作者 程廓 李永刚 王大为 杨宝玲 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期1286-1296,共11页
目的:通过免疫沉淀联合质谱分析的方法筛选发热伴血小板减少综合征病毒(SFTSV)非结构蛋白(NSs)的宿主互相作用(互作)蛋白,探讨互作蛋白的功能、亚细胞定位及参与的生物途径,为阐明SFTSV的复制和致病机制提供依据。方法:将真核表达载体pS... 目的:通过免疫沉淀联合质谱分析的方法筛选发热伴血小板减少综合征病毒(SFTSV)非结构蛋白(NSs)的宿主互相作用(互作)蛋白,探讨互作蛋白的功能、亚细胞定位及参与的生物途径,为阐明SFTSV的复制和致病机制提供依据。方法:将真核表达载体pSFTSV-NSs-Flag (实验组)和Flag-CMV-3 (阴性组)分别转染进人胚胎肾293T细胞中,同时设置空白组(不进行任何处理)。收集各组细胞裂解液,采用间接免疫荧光和Western blotting法验证SFTSV NSs在宿主细胞中的表达及定位。蛋白裂解液经protein A/G处理,采用免疫沉淀法富集与NSs结合的宿主蛋白,通过银染和考马斯亮蓝染色初步分析捕获的互作蛋白,观察各组蛋白差异条带。采用液相色谱和串联质谱技术得到蛋白质的序列信息,保留可信蛋白基于UniProt数据库检索,对鉴定到的蛋白进行基因本体论(GO)功能富集分析、蛋白结构域和功能位点数据库(IPR)、真核生物同源蛋白簇(KOGs)功能注释、京都基因与基因组百科全书(KEGG)信号通路富集分析、亚细胞定位和转录因子(TF)功能注释,确定互作蛋白的亚细胞结构、基因功能及参与的生物过程。结果:SFTSV NSs在相对分子质量33 000处表达单一特异性条带,免疫荧光检测其定位于细胞质中,且聚集呈砂粒体包涵体样。银染和考马斯亮蓝染色,实验组和阴性组均存在显著差异条带。质谱筛选出46种潜在互作蛋白;GO功能富集分析、KOGs功能注释和KEGG信号通路富集分析,与病毒翻译、细胞代谢及蛋白质运输相关的生物途径富集到较多数目的蛋白,注释中有8种蛋白具有中间丝蛋白结构域。亚细胞定位所占百分率最高的是细胞质蛋白;与NSs定位场所一致。TF功能注释,有1种蛋白来自NF-Y家族。结论:互作蛋白在协助蛋白质正确折叠、参与核糖体翻译和构成细胞骨架等进程中发挥作用,可能参与了抗病毒复制,可作为候选蛋白进一步研究SFTSV的复制机制。 展开更多
关键词 发热伴血小板减少综合征病毒 非结构蛋白 蛋白-蛋白互相作用 免疫沉淀 质谱
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Regulating crystal phase of TiO_(2) to enhance catalytic activity of Ni/TiO_(2) for solar-driven dry reforming of methane 被引量:2
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作者 HE Zhanjun GONG Kun +3 位作者 DAI Yuanyuan NIU Qiang LIN Tiejun ZHONG Liangshu 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第9期1203-1213,共11页
Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by... Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by varying the calcination temperature of anatase-TiO_(2).Structural characterizations revealed that a distinct TiO_(x) coating on the Ni nanoparticles(NPs)was evident for Ni/TiO_(2)-700 catalyst due to strong metal-support interaction.It is observed that the TiOx overlayer gradually disappeared as the ratio of rutile/anatase increased,thereby enhancing the exposure of Ni active sites.The exposed Ni sites enhanced visible light absorption and boosted the dissociation capability of CH4,which led to the much elevated catalytic activity for Ni/TiO_(2)-950 in which rutile dominated.Therefore,the catalytic activity of solar-driven DRM reaction was significantly influenced by the rutile/anatase ratio.Ni/TiO_(2)-950,characterized by a predominant rutile phase,exhibited the highest DRM reactivity,with remarkable H_(2) and CO production rates reaching as high as 87.4 and 220.2 mmol/(g·h),respectively.These rates were approximately 257 and 130 times higher,respectively,compared to those obtained on Ni/TiO_(2)-700 with anatase.This study suggests that the optimization of crystal structure of TiO_(2) support can effectively enhance the performance of photothermal DRM reaction. 展开更多
关键词 dry reforming of methane photothermal catalysis crystal phase TiO_(2) metal-support interaction
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Numerical Simulation of Multiple Collisions Between Ice Ridge and Polar Ship
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作者 JIA Bin JU Lei +2 位作者 SHI Li WANG Qing PANG Fu-zhen 《船舶力学》 EI CSCD 北大核心 2024年第12期1908-1924,共17页
Ships navigating in ice-covered regions will inevitably collide with ice ridges.Compared to other ice bodies,ice ridges exhibit more complicated mechanical behaviors due to the scale and structure characteristics.In t... Ships navigating in ice-covered regions will inevitably collide with ice ridges.Compared to other ice bodies,ice ridges exhibit more complicated mechanical behaviors due to the scale and structure characteristics.In this paper,nonlinear finite element method is used to investigate the interaction between a polar ship and an ice ridge.The ice ridge is modelled as elastic-plastic material based on Drucker-Prager yield function,with the consideration of the influence of cohesion,friction angle and material hardening.The material model is developed in LS-DYNA and solved using semi-implicit mapping algorithm.The stress distribution of ice ridge and ship,and the ice load history are evaluated through the simulation of multiple collisions.In addition,parametric analysis is performed to investigate the influence of ridge thickness and impact velocity on the ice load and energy absorption. 展开更多
关键词 ice ridge SHIP nonlinear FEM ice load interaction STRENGTH
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富营养化水体生态修复技术中凤眼莲与磷素的互作机制 被引量:10
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作者 张迎颖 严少华 +3 位作者 刘海琴 秦红杰 闻学政 张志勇 《生态环境学报》 CSCD 北大核心 2017年第4期721-728,共8页
为进一步完善富营养水体生态修复技术体系,提升除磷效能,从磷素对水体富营养化进程的贡献展开分析,指出磷素是制约浮游藻类生长的关键因素,并分析了凤眼莲Eichhornia crassipes与磷素的互相作用机制,即磷素对凤眼莲植株生理性状具有影响... 为进一步完善富营养水体生态修复技术体系,提升除磷效能,从磷素对水体富营养化进程的贡献展开分析,指出磷素是制约浮游藻类生长的关键因素,并分析了凤眼莲Eichhornia crassipes与磷素的互相作用机制,即磷素对凤眼莲植株生理性状具有影响,而凤眼莲对磷的吸收同化作用又促成了除磷目标。研究显示:随着水中可获取磷浓度的升高,凤眼莲吸收的磷素更多地分配在茎叶部分。水体磷浓度过高,将激发凤眼莲对磷素的超累积性;水环境中磷素缺乏,凸显出凤眼莲的根部形态可塑性。水体氮磷浓度比(N/P)为2.5~5时凤眼莲可获得最大生物产量。凤眼莲对可溶性反应磷具有极优的净化效果;在藻华爆发期间,凤眼莲能通过密集根系捕获飘移的蓝藻,并吸收利用藻细胞衰亡所释放的磷素。在工程实践中,需统筹考量磷去除效果与去除速率,在高污染负荷的情况下,应优先考虑去除速率;当水再生作为饮用水源时,应优先考虑去除效果。凤眼莲生态修复工程设计须遵循先后次序:(1)最终水质目标;(2)生物产量;(3)植株品质。最终水质目标及营养去除与营养负荷水平密切相关。在大型湖泊和水库实践应用中,须先控制外源磷负荷,再逐步削减内源磷负荷。利用凤眼莲深度净化污水处理厂尾水,或在高负荷的入河、湖口处种养凤眼莲,可减轻外源磷负荷;在蓝藻积累和衰亡的背风区域种养凤眼莲,以吸收蓝藻释放的营养,从而减轻内源磷负荷。 展开更多
关键词 凤眼莲 生态修复 互相作用
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Computational Simulation of Aptamer-target Binding Mechanisms
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作者 YANG Yuan-Yuan XU Fei WU Xiu-Xiu 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第11期1550-1562,共13页
Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as bioch... Aptamers are a type of single-chain oligonucleotide that can combine with a specific target.Due to their simple preparation,easy modification,stable structure and reusability,aptamers have been widely applied as biochemical sensors for medicine,food safety and environmental monitoring.However,there is little research on aptamer-target binding mechanisms,which limits their application and development.Computational simulation has gained much attention for revealing aptamer-target binding mechanisms at the atomic level.This work summarizes the main simulation methods used in the mechanistic analysis of aptamer-target complexes,the characteristics of binding between aptamers and different targets(metal ions,small organic molecules,biomacromolecules,cells,bacteria and viruses),the types of aptamer-target interactions and the factors influencing their strength.It provides a reference for further use of simulations in understanding aptamer-target binding mechanisms. 展开更多
关键词 computational simulation APTAMER TARGET binding mechanism intermolecular forces
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Coacervation of oxidized glutathione with a cationic surfactant and the application in dye removal
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作者 Yue Zhang Yu Liu +2 位作者 Li Zhao Ce Wang Baocai Xu 《日用化学工业(中英文)》 CAS 北大核心 2024年第12期1423-1430,共8页
Coacervation of oxidized glutathione(GSSG)and a cationic surfactant,didodecyldimethylammonium bromide(DDAB),was constructed mainly driven by the electrostatic and hydrophobic interactions.The pH-dependent coacervate o... Coacervation of oxidized glutathione(GSSG)and a cationic surfactant,didodecyldimethylammonium bromide(DDAB),was constructed mainly driven by the electrostatic and hydrophobic interactions.The pH-dependent coacervate of GSSG-DDAB(1∶4,mol/mol)was analyzed.Under acidic and neutral conditions,a turbid suspension of droplets is observed,and alkaline pH results in the phase separation of coacervates as the top phase.The coacervate phase exhibits good performance(extraction efficiency>85%)in extracting several dyes from water,including brilliant yellow,acid red 13,cresyl violet acetate,eriochrom blue SE,and 4-hydroxyazobenzene.The dyes are added into the suspension in acidic conditions.Then,the dyes are enriched and extracted along with the coacervates as the top phase when pH is adjusted to~10.Coacervation of GSSG with DDAB provides a simple approach to extract organic pollutants in wastewater treatment. 展开更多
关键词 COACERVATION oxidized glutathione dye removal electrostatic interaction hydrophobic effect
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Remote electron effects and π-π interactions of α-diimine nickel complexes
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作者 Yizhan Wang Hailong He Dan Peng 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第9期17-22,68,共7页
The seminal report ofα-diimine palladium and nickel catalysts in 1995 represented a major breakthrough in the preparation of functionalized polyolefin materials.Owing to the high abundance and low cost of nickel,nick... The seminal report ofα-diimine palladium and nickel catalysts in 1995 represented a major breakthrough in the preparation of functionalized polyolefin materials.Owing to the high abundance and low cost of nickel,nickel-based catalysts have great application prospects in the industrialization process of olefin coordination polymerization.In this work,various N-aryl substituents with different electronic effects were synthesized and introduced intoα-diimine ligands.The aspreparedα-diimine nickel catalysts showed high polymerization activity(0.9×10^(7)–3.0×10^(7)g·mol^(−1)·h^(−1))in ethylene polymerization,generating polyethylene products with adjustable molecular weights(Mn values:7.4×10^(4)–146.9×10^(4)g·mol^(−1))and branching densities(31/1000 C–68/1000 C).The resulting polyethylene products showed excellent mechanical properties,with high tensile strength(up to 25.0 MPa)and high strain at break values(up to 3890%).The copolymerization of ethylene and polar monomers can also be achieved by these nicekel complexes,ultimately preparing functionalized polyolefins. 展开更多
关键词 α-diimine nickel catalyst ethylene polymerization π-πinteraction effect electronic effect polar monomer
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A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment
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作者 MAO Jian-feng LI Dao-hang +3 位作者 YU Zhi-wu CAI Wen-feng GUO Wei ZHANG Guang-wen 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2532-2544,共13页
Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can b... Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic characteristic.The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element method.The model is proven to be applicable by comparing with Monte Carlo simulation.By applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment.Moreover,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated.The results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval. 展开更多
关键词 maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method
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