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The evolutionarily diverged single-stranded DNA-binding proteins SSB1/SSB2 differentially affect the replication,recombination and mutation of organellar genomes in Arabidopsis thaliana
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作者 Weidong Zhu Jie Qian +6 位作者 Yingke Hou Luke R.Tembrock Liyun Nie Yi-Feng Hsu Yong Xiang Yi Zou Zhiqiang Wu 《Plant Diversity》 2025年第1期127-135,共9页
Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(... Single-stranded DNA-binding proteins(SSBs)play essential roles in the replication,recombination and repair processes of organellar DNA molecules.In Arabidopsis thaliana,SSBs are encoded by a small family of two genes(SSB1 and SSB2).However,the functional divergence of these two SSB copies in plants remains largely unknown,and detailed studies regarding their roles in the replication and recombination of organellar genomes are still incomplete.In this study,phylogenetic,gene structure and protein motif analyses all suggested that SSB1 and SSB2 probably diverged during the early evolution of seed plants.Based on accurate long-read sequencing results,ssb1 and ssb2 mutants had decreased copy numbers for both mitochondrial DNA(mtDNA)and plastid DNA(ptDNA),accompanied by a slight increase in structural rearrangements mediated by intermediate-sized repeats in mt genome and small-scale variants in both genomes.Our findings provide an important foundation for further investigating the effects of DNA dosage in the regulation of mutation frequencies in plant organellar genomes. 展开更多
关键词 SSB Organellar genomes replication Recombination MUTATION
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Dynamic Multi-Objective Gannet Optimization(DMGO):An Adaptive Algorithm for Efficient Data Replication in Cloud Systems
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作者 P.William Ved Prakash Mishra +3 位作者 Osamah Ibrahim Khalaf Arvind Mukundan Yogeesh N Riya Karmakar 《Computers, Materials & Continua》 2025年第9期5133-5156,共24页
Cloud computing has become an essential technology for the management and processing of large datasets,offering scalability,high availability,and fault tolerance.However,optimizing data replication across multiple dat... Cloud computing has become an essential technology for the management and processing of large datasets,offering scalability,high availability,and fault tolerance.However,optimizing data replication across multiple data centers poses a significant challenge,especially when balancing opposing goals such as latency,storage costs,energy consumption,and network efficiency.This study introduces a novel Dynamic Optimization Algorithm called Dynamic Multi-Objective Gannet Optimization(DMGO),designed to enhance data replication efficiency in cloud environments.Unlike traditional static replication systems,DMGO adapts dynamically to variations in network conditions,system demand,and resource availability.The approach utilizes multi-objective optimization approaches to efficiently balance data access latency,storage efficiency,and operational costs.DMGO consistently evaluates data center performance and adjusts replication algorithms in real time to guarantee optimal system efficiency.Experimental evaluations conducted in a simulated cloud environment demonstrate that DMGO significantly outperforms conventional static algorithms,achieving faster data access,lower storage overhead,reduced energy consumption,and improved scalability.The proposed methodology offers a robust and adaptable solution for modern cloud systems,ensuring efficient resource consumption while maintaining high performance. 展开更多
关键词 Cloud computing data replication dynamic optimization multi-objective optimization gannet optimization algorithm adaptive algorithms resource efficiency SCALABILITY latency reduction energy-efficient computing
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Features and mechanisms of long-lived Myotis somatic fibroblasts in response to DNA replication stress
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作者 Xiao-Yan Huang Xiu-Yun Liu +5 位作者 Wei Wang Gao-Jing Liu You-Long Zhu Xiao Wen Kai-Qin Li Bo Zhao 《Zoological Research》 2025年第3期709-721,共13页
The DNA replication stress(RS)response is crucial for maintaining cellular homeostasis and promoting physiological longevity.However,the mechanisms by which long-lived species,such as bats,regulate RS to maintain geno... The DNA replication stress(RS)response is crucial for maintaining cellular homeostasis and promoting physiological longevity.However,the mechanisms by which long-lived species,such as bats,regulate RS to maintain genomic stability remain unclear.Also,recent studies have uncovered noncanonical roles of ribosome-associated factors in maintaining genomic stability.In this study,somatic skin fibroblasts from the long-lived big-footed bat(Myotis pilosus)were examined,with results showing that bat cells exhibited enhanced RS tolerance compared to mouse cells.Comparative transcriptome analysis under RS conditions revealed pronounced species-specific transcriptional differences,including robust up-regulation of ribosome biogenesis genes in bat cells and a markedly reduced activation of the P53 signaling pathway.These features emphasize a distinct homeostatic strategy in bat cells.Nuclear fragile X mental retardation-interacting protein 1(Nufip1),a ribosome-associated factor highly expressed in bat fibroblasts,was identified as a potential integrator of ribosomal and P53 signaling via its association with ribosomal protein S27-like(Rps27l).These findings provide direct cellular and molecular evidence for a noncanonical RS response in bats,highlighting a deeper understanding of the biological characteristics and genomic maintenance mechanisms of long-lived species. 展开更多
关键词 Long-lived species Myotis pilosus DNA replication stress Ribosome biogenesis P53 signaling Nufip1 Rps27l
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CRTC3 restricts SARS-CoV-2 replication and is antagonized by CREB
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作者 Li Yang Xiao-Tao Zeng +8 位作者 Rong-Hua Luo Ying Tang Si-Xue Ren Xin-Yan Long Xiang-Hui Fu Wan-Jiang Zhang Hai-Yan Ren Yong-Tang Zheng Wei Cheng 《Virologica Sinica》 2025年第1期92-108,共17页
Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previo... Virus-encoding RNA-dependent RNA polymerase(RdRp)is essential for genome replication and gene transcription of human coronaviruses(HCoVs),including severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).We previously identified the interaction between the catalytic subunit NSP12 of SARS-CoV-2 RdRp and the host protein CREB-regulated transcription coactivator 3(CRTC3),a member of the CRTC family that regulates cyclic AMP response element-binding protein(CREB)-mediated transcriptional activation.Currently,the implication of CRTC3 in the pathogenesis of HCoVs is poorly understood.Herein,we demonstrated that CRTC3 attenuates RdRp activity and SARS-CoV-2 genome replication,therefore reducing the production of progeny viruses.The interaction of CRTC3 with NSP12 contributes to its inhibitory effect on RdRp activity.Furthermore,we expanded the suppressive effects of two other CRTC family members(CRTC1 and CRTC2)on the RdRp activities of lethal HCoVs,including SARS-CoV-2 and Middle East respiratory syndrome coronavirus(MERS-CoV),along with the CREB antagonization.Overall,our research suggests that CRTCs restrict the replication of HCoVs and are antagonized by CREB,which not only provides new insights into the replication regulation of HCoVs,but also offers important information for the development of anti-HCoV interventions. 展开更多
关键词 Human coronaviruses(HCoVs) RNA-Dependent RNA polymerase (RdRp) CREB-regulated transcription coactivator 3(CRTC3) Virus replication Virus-host interaction Cyclic AMP response element-binding protein(CREB)
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Topoisomerase Ⅱα orchestrates secretion of IL-6 and IL-8 with human papillomavirus replication
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作者 Yanfei Liu Zi Han +7 位作者 Paul Kaminski Chengcheng Tao Xiaoge Li Mengmeng Liu Yang Li Ying Jia Junfen Xu Shiyuan Hong 《Virologica Sinica》 2025年第6期946-961,共16页
High-risk human papillomavirus(HPV)replication requires deregulation of host DNA damage response(DDR)and inflammatory pathways.DNA topoisomerase 2β(Top2β)was previously shown to promote HPV replication.We investigat... High-risk human papillomavirus(HPV)replication requires deregulation of host DNA damage response(DDR)and inflammatory pathways.DNA topoisomerase 2β(Top2β)was previously shown to promote HPV replication.We investigated whether its paralog Top2α protein acts similarly to the virus.Elevated levels of Top2α are consistently observed in cervical intraepithelial lesions and the related carcinomas,as well as in HPV-positive cell lines.Silencing Top2α with shRNA severely suppresses HPV genome maintenance and amplification,but in a DDR-independent manner.Instead,Top2α facilitates secretion of interleukin(IL)-6 and IL-8,which are necessary for HPV replication.Mechanistically,this manipulation is regulated by toll-like receptor 4(TLR4).Top2α binds to the TLR4 promoter to transcriptionally induce TLR4 expression.Blockade of TLR4 signaling by the specific inhibitor TAK-242 significantly reduces the secreted IL-6/IL-8 levels and HPV replication.Overall,our results reveal a novel role of Top2α to shape the inflammatory microenvironment that benefits HPV replication,making it a promising therapeutic target for HPV-associated diseases. 展开更多
关键词 Human papillomavirus(HPV) replication Topoisomerase IL-6/IL-8 secretion TLR4
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谁更像“人”?模型类型与人格设定对大语言模型复刻传播学实验准确率的影响
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作者 曾秀芹 陈珂璐 《新闻与传播评论》 北大核心 2026年第1期25-39,共15页
以ChatGPT-4o、DeepSeek-R1、豆包-1.5、Kimi-K1.5四种主流大语言模型为对象,采用2(有vs.无大五人格设定)×4(模型类型)实验设计,构建虚拟被试资料以复刻新闻传播学实验。结果显示,各模型拟合表现存在差异:DeepSeek-R1在模拟真人平... 以ChatGPT-4o、DeepSeek-R1、豆包-1.5、Kimi-K1.5四种主流大语言模型为对象,采用2(有vs.无大五人格设定)×4(模型类型)实验设计,构建虚拟被试资料以复刻新闻传播学实验。结果显示,各模型拟合表现存在差异:DeepSeek-R1在模拟真人平均趋势与行为变异性方面最优;ChatGPT-4o的总体方差拟合偏差较大,但主效应、间接效应复刻的准确性与稳定性较为突出。人格设定的影响方面,无大五人格组描述性统计更贴近真人,而有大五人格组因果效应复刻更稳定,唯一完整复刻两个主效应的模型即来自该组。中介效应复刻成功率偏低,但人格设定可在一定程度上缓解模型输出的方向与效应偏离趋势。此外,研究基于ChatGPT-4o进一步发现,实验对象类型(真人组vs.无大五人格组vs.有部分大五人格组vs.有全部大五人格组)对主效应与中介机制部分产生显著调节作用,其中大五人格设定可一定程度抑制模型极端响应。研究实现多模型横向比较与人格设定控制下的复刻实验,验证了大五人格设定对提升模型模拟精度的积极作用,同时指出模型复刻复杂心理机制的局限性,推动传播学实验向“人机共演”的新范式转变,也拓展“媒介即延伸”在智能传播语境下的现实外延。 展开更多
关键词 大语言模型 大五人格 复刻研究 硅基被试
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政策再生产视角下老旧小区改造的话语演变与治理转向
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作者 刘铮 李倩如 《风景园林》 北大核心 2026年第2期40-49,共10页
【目的】基于政策再生产理论,分析中国老旧小区改造政策的演进特征与城市差异,为推动老旧小区改造的制度完善与治理创新提供实证依据。【方法】选取2005—2025年中央及地方改造政策文本,采用主题模型提取各阶段政策主题,并结合Word2Vec... 【目的】基于政策再生产理论,分析中国老旧小区改造政策的演进特征与城市差异,为推动老旧小区改造的制度完善与治理创新提供实证依据。【方法】选取2005—2025年中央及地方改造政策文本,采用主题模型提取各阶段政策主题,并结合Word2Vec词向量模型计算主题相似度,构建政策主题演化路径。基于住建部最新颁布的八批次城镇老旧小区改造可复制政策机制清单,进一步论证现阶段政策的话语构成与制度特征。【结果】老旧小区改造政策实现了从政策实验探索向政策机制完善的阶段演化,近年来呈现出多元共治的治理转向特征。同时,各地改造政策制定从早期的差异化探索逐步走向治理机制协同深化。【结论】老旧小区改造的治理投入持续提升,已实现从政策试验向制度完善的系统演进。进入存量增效提质阶段,老旧小区改造工作应进一步以“设计治理”理念为指引,充分吸收分借鉴可复制政策机制清单的创新经验,最终实现城市空间品质与治理效能的持续提升。 展开更多
关键词 城市更新 老旧小区改造 政策再生产 可复制政策机制清单 政策文本分析 主题建模分析
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A Novel Replication-competent Adenovirus CNHK500 in the Treatment of Heptocellular Carcinoma In Vitro 被引量:1
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作者 张琪 吴孟超 +2 位作者 李月敏 彭林辉 钱其军 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第2期70-73,124,共5页
Objective: To evaluate the therapeutic efficacy of replicative adenovirus CNHK500 in the treatment of hepatocellular carcinoma. Methods: Virus proliferation assay, cell viability assay and Western blot were performed ... Objective: To evaluate the therapeutic efficacy of replicative adenovirus CNHK500 in the treatment of hepatocellular carcinoma. Methods: Virus proliferation assay, cell viability assay and Western blot were performed to assess the selective replication and cytolysis of CNHK500 in telomerase positive liver cancer cells Hep3B, HepGII, SMMC7721 and in normal cells. Results: The replicative multiples of CNHK500 in HepGII, Hep3B and SMMC7221 after 96 h of virus proliferation were 52 000, 396 984.9 and 632 911.3 fold respectively, similar to those of wtAd5. However, CNHK500 demonstrated more significant attenuated replicative ability in normal cell lines than wtAd5. CNHK500 replicated only 3.1-100 fold at 96 h, while the wtAd5 still reached 3160-17 357 fold. CNHK500 could cause half of HepGII cells death within 7 days at MOI 2, in Hep3B cell lines the IC50 was as low as MOI 0.01, whereas the IC50 in BJ cell was as high as MOI 1000. CNHK500 E1A protein could only be detected in hepatocellular cancer cells but not in normal cells under normoxia. E1B protein could only be detected under hypoxia condition at a MOI of 1. Conclusion: CNHK500 can efficiently replicate in and kill liver cancer cells as well as wtAd5 do while it is severely attenuated in proliferation and cytolysis among normal cells. It would be a prominsing strategy for liver cancer tratment. 展开更多
关键词 replicative adenovirus hepatocellular carcinoma VIROTHERAPY TELOMERASE HYPOXIA
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SQL Server CE中RDA与Replication的研究 被引量:5
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作者 苏伟 陈敏 李紧 《现代计算机》 2010年第2期108-112,共5页
介绍移动数据库SQL Server CE及其特点,详细分析RDA(远程数据访问)和Replica-tion(合并复制)数据同步技术,探讨两种技术的各自特点和应用环境,描述两种数据同步技术的实现过程,比较这两种技术适合的环境。
关键词 移动数据库 SQL Server CE 数据同步技术 RDA replication
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Replication-selective Oncolytic Adenovirus CNHK300 in the Treatment of Breast Cancer Cell Lines in vitro
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作者 李月敏 宋三泰 +3 位作者 江泽飞 徐建明 张琪 钱其军 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第6期334-337,共4页
Objective: To evaluate the tumor selectivity and therapeutic efficiency of replication-competent adenovirus CNHK300 on human breast cancer cells. Methods: RT-PCR was used to detect the hTERT mRNA activity in various... Objective: To evaluate the tumor selectivity and therapeutic efficiency of replication-competent adenovirus CNHK300 on human breast cancer cells. Methods: RT-PCR was used to detect the hTERT mRNA activity in various breast cancer and normal fibroblast cell lines. Virus proliferation assay, cell viability assay and Western blot were applied to evaluate the proliferation and cytolysis selectivity of CNHK300. Results: The telomerase activity of MCF-7, BT-549 and SK-BR-3 was positive, while telomerase in MRC-5 and BJ was negative. The progeny virus titers in MCF-7, BT-549 and SK-BR-3 after 48 h of CNHK300 exposure was 40 625, 1 265 and 20 000 fold higher than those of 0 h, even slightly higher than those of wtAd5 (except in SK-BR-3). ONYX-015 virus proliferation ability was weaker than that of CNHK300 in cancer cells. However, CNHK300 exhibited attenuated replicative ability as compared with wtAd5 in MRC-5 and BJ. The CNHK300 replicatative multiple was 63 and 192 fold at 48 h respectively, while the wtAd5 still multiplied 3 160-4 846 fold. CNHK300 could cause about half of breast cancer cells to die within 7 days at MOI 10 pfu/cell and below, whereas the IC50 in BJ and MRC-5 was as high as MOI 100 pfu/cell. CNHK300 E1A protein could be detected in breast cancer cells and 293 cells but not in normal fibroblast cells. Conclusion: hTERT promoter can successfully modulate the CNHK300 to be selectively replicated in breast cancer cells positive for telomerase, which may be a potential treatment strategy in breast cancer. 展开更多
关键词 gene therapy VIROTHERAPY replicative adenovirus breast cancer
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一种基于Active Replication的TCP连接容错技术
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作者 程斌 金海 徐婕 《计算机工程与科学》 CSCD 2005年第9期71-73,共3页
本文提出一种基于ActiveReplication的TCP连接容错技术(ARTCP),采用两层的Cluster结构,并通过前端的分发器和聚合网关机维持多个同步的TCP连接副本,达到了相互容错的效果。测试结果表明,该技术不仅保证网络服务连接级的高可用性,而且具... 本文提出一种基于ActiveReplication的TCP连接容错技术(ARTCP),采用两层的Cluster结构,并通过前端的分发器和聚合网关机维持多个同步的TCP连接副本,达到了相互容错的效果。测试结果表明,该技术不仅保证网络服务连接级的高可用性,而且具有恢复时间短、开销小的优势。 展开更多
关键词 TCP 容错 ACTIVE replication 同步
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人腺病毒受体及复制相关宿主因子研究进展
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作者 经玲 林颖 +2 位作者 朱云 雷晓波 谢正德 《病毒学报》 北大核心 2026年第1期281-298,共18页
人腺病毒(Human adenovirus,HAdV)是一种引发多种人类疾病的病原体,因其高传染性、在高度密闭、拥挤的环境中容易导致暴发流行,对人类健康构成严重威胁。HAdV的入侵依赖于宿主细胞表面的特定受体,这些受体在病毒附着和入侵过程中扮演关... 人腺病毒(Human adenovirus,HAdV)是一种引发多种人类疾病的病原体,因其高传染性、在高度密闭、拥挤的环境中容易导致暴发流行,对人类健康构成严重威胁。HAdV的入侵依赖于宿主细胞表面的特定受体,这些受体在病毒附着和入侵过程中扮演关键角色。此外,宿主细胞内的多种因子在病毒复制周期的不同阶段发挥重要功能,包括病毒基因组转录、翻译、复制,以及子代病毒的组装。这些宿主因子涉及细胞分化、信号传导、免疫调控等多个细胞生命过程。本文综述了HAdV入侵所依赖的宿主受体及病毒复制相关的关键宿主因子的最新研究进展,以期加深对HAdV致病机制的理解,并为新型抗病毒药物的开发提供参考。 展开更多
关键词 人腺病毒 细胞受体 宿主因子 病毒复制
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POP基因敲除PK-15细胞系的建立及其对口蹄疫病毒增殖的影响
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作者 卢炳州 李建斌 +10 位作者 王姿逸 杨洋 赵陇和 李亚军 刘华南 李明桂 马坤 郑海学 郭建宏 茹毅 郝荣增 《中国兽医科学》 北大核心 2026年第1期27-32,共6页
为探索脯氨酰寡肽酶(POP)缺失对口蹄疫病毒(FMDV)增殖的影响,采用CRISPR/Cas9基因编辑技术,通过慢病毒包装、嘌呤霉素筛选及有限稀释法单克隆培养,构建POP基因敲除的PK-15细胞系(POP-KO),并以野生型PK-15(WT-PK-15)细胞为对照,接种FMDV... 为探索脯氨酰寡肽酶(POP)缺失对口蹄疫病毒(FMDV)增殖的影响,采用CRISPR/Cas9基因编辑技术,通过慢病毒包装、嘌呤霉素筛选及有限稀释法单克隆培养,构建POP基因敲除的PK-15细胞系(POP-KO),并以野生型PK-15(WT-PK-15)细胞为对照,接种FMDV后采用实时荧光定量RT-PCR检测FMDV RNA水平,通过Western-blot分析病毒结构蛋白VP1表达量及病毒滴度测定(TCID50)方法综合评估POP缺失对FMDV增殖的影响。结果表明,与WT-PK-15细胞相比,POP-KO细胞中VP1蛋白表达水平显著降低(P<0.001),病毒滴度降低了1.24 lg TCID50/m L(P<0.001),FMDV RNA拷贝数显著低于对照细胞(P<0.001)。本研究成功建立了POP基因敲除的PK-15细胞系,证实POP缺失可显著抑制FMDV的增殖,揭示POP是FMDV复制的关键宿主促进因子。 展开更多
关键词 脯氨酰寡肽酶 CRISPR/Cas9 基因敲除 口蹄疫病毒 病毒增殖
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Replication Server数据复制技术及实例
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作者 毕利 汤效琴 《铁路计算机应用》 2007年第9期55-56,共2页
3实例下面介绍在Sybase Workspace 1.5开发平台上,如何开发一个完整的Replication Server系统应用。实例是大型超市的POS系统数据库到经理办公室的销售数据分析数据库的复制。超市的销售数据在数据库(server_1.source)中,进行数据分... 3实例下面介绍在Sybase Workspace 1.5开发平台上,如何开发一个完整的Replication Server系统应用。实例是大型超市的POS系统数据库到经理办公室的销售数据分析数据库的复制。超市的销售数据在数据库(server_1.source)中,进行数据分析的是数据仓库(server_2.IQ)。各个超市的销售数据在数据库中是相当繁多的,但对于提供决策支持来说,只需要分析部分数据就够了。 展开更多
关键词 replication SERVER系统 数据复制技术 实例 分析数据库 SYBASE 销售数据 大型超市
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Replication Server数据复制技术及实例
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作者 毕利 汤效琴 《铁路计算机应用》 2007年第8期56-57,共2页
介绍Replication Server的复制模型和应用程序体系结构,并举例如何利用Sybase Workspace构建一个完整的Replication Server系统应用,希望能给开发和管理Replication Server系统的管理员一些借鉴。
关键词 数据复制模型 replication SERVER SYBASE WORKSPACE 数据库开发
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Sybase Replication Server12.0的复制服务器技术研究及应用 被引量:1
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作者 朱跃龙 洪筱菡 《计算机与现代化》 2002年第12期59-61,64,共4页
介绍了分布式数据库数据复制的概念和方法 ,着重探讨了SybaseReplicationServer 12 .0复制服务器机制的基本原理和主要功能 ,给出了一个基于异构数据类型支持 (HDS)的应用实例。
关键词 SybasereplicationServer12.0 复制服务器 分布式数据库 数据复制
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端粒延长替代机制在端粒酶阴性肿瘤和衰老细胞中的作用与机制
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作者 贾同欣 熊梦婕 +4 位作者 侯凯龙 刘嘉华 张昊楠 贾舒婷 刘静 《生物化学与生物物理进展》 北大核心 2026年第1期92-104,共13页
端粒延长替代机制(alternative lengthening of telomeres,ALT)是一种高度依赖于同源重组的DNA损伤修复过程,其通过DNA修复机制介导端粒DNA的合成,因此该过程也伴随着一些独特的表型:比如复制压力累积、小分子泛素相关修饰物蛋白(small ... 端粒延长替代机制(alternative lengthening of telomeres,ALT)是一种高度依赖于同源重组的DNA损伤修复过程,其通过DNA修复机制介导端粒DNA的合成,因此该过程也伴随着一些独特的表型:比如复制压力累积、小分子泛素相关修饰物蛋白(small ubiquitin-related modifier protein,SUMO)依赖的ALT相关早幼粒细胞白血病(promyelocytic leukemia,PML)蛋白小体(ALT-associated PML bodies,APBs)上调以及染色质的动态重塑等。大部分的肿瘤细胞主要通过重新激活端粒酶延长端粒,而大约10%~15%的肿瘤细胞由于缺失端粒酶活性,则是通过启动ALT来维持端粒长度。与端粒酶阴性肿瘤类似,绝大多数体细胞由于端粒酶活性低或缺失导致细胞在分裂增殖过程中端粒逐渐缩短最终进入衰老状态。值得注意的是,有研究发现,在细胞衰老的进程中也伴随着复制压力积累和APBs的增加等类似“ALT激活”的现象,提示衰老细胞与端粒酶阴性肿瘤之间可能具有某些共同的调控机制。尽管这些“ALT激活”的衰老细胞中端粒长度并未有效延长,但ALT可能是衰老细胞逃逸衰老进而肿瘤化的途径之一。因此,本文针对端粒酶阴性肿瘤和衰老细胞典型特征的相关性进行较全面的综述,阐明ALT在调控细胞衰老和肿瘤发生过程中的潜在机制,为临床上端粒酶阴性肿瘤的治疗提供潜在的靶点和策略。 展开更多
关键词 端粒延长替代机制 端粒酶阴性肿瘤 衰老细胞 复制压力 染色质可及性
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北京地区埃可病毒18型基因组及细胞感染特征分析
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作者 韩振志 贾立平 +4 位作者 蔺晨博 朱汝南 黄辉 邓莉 赵林清 《病毒学报》 北大核心 2026年第1期14-22,共9页
目的探讨北京地区流行的埃可病毒18型(Echovirus 18,E18)基因组、病毒进化及体外感染特征。方法对2010年3月至2019年10月收集的首都医科大学附属首都儿童医学中心诊断为手足口病、疱疹性咽峡炎等的患儿咽拭子样本通过实时荧光定量PCR(rR... 目的探讨北京地区流行的埃可病毒18型(Echovirus 18,E18)基因组、病毒进化及体外感染特征。方法对2010年3月至2019年10月收集的首都医科大学附属首都儿童医学中心诊断为手足口病、疱疹性咽峡炎等的患儿咽拭子样本通过实时荧光定量PCR(rRT-PCR)进行了通用型肠道病毒(pan-Enterovirus,pan-EV)及肠道病毒A组71型(Enterovirus A71,EV-A71)、柯萨奇病毒A(Coxsackievirus A,CVA)组16型(CVA16)、CVA6及CVA10回顾性筛查;对确定为pan-EV阳性但不能确定血清型的样本,经RT-PCR扩增VP1编码区,通过序列分析进行分型;确定为埃可病毒18型(E18)阳性的样本接种RD细胞,获得分离株,进行宏基因组测序获得全长基因组序列,确定基因型;多方法(RDP4、SimPlot、系统进化树)进行重组事件分析。通过rRT-PCR绘制生长曲线,比较RD与Hep-2细胞中代表株感染特征。结果7652例样本中,E18阳性17例(0.20%,17/7652);RD细胞中成功分离到14株,VP1编码区全序列分析显示所有分离株均属C2基因亚型,与我国既往流行株聚为一簇。以s6868为代表株,基因组全长7412 nt,与原型株(Metcalf)核苷酸序列相似性为80.30%,7种算法均提示其在P3编码区(4006-6592 nt)与CVB5重组。增殖实验表明,在RD细胞中E18 RNA拷贝数在感染12h后从lg6.5934±0.1714拷贝/μL增加至lg8.1852±0.2712拷贝/μL,在48h(lg9.3356±0.3829拷贝/μL)达到平台期,高于其在感染Hep-2细胞12h后的lg5.7121±0.1585拷贝/μL。结论2010-2019年北京地区流行的E18分离株均属于C2基因亚型,s6868毒株在P3编码区与CVB5可能存在重组。E18在RD细胞中的增殖效率高于Hep-2细胞,RD细胞可作为E18体外研究细胞模型。 展开更多
关键词 埃可病毒18型(E18) 进化分析 重组 增殖特征
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多聚胞嘧啶结合蛋白2在大别班达病毒感染中的作用及机制
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作者 郁心怡 戴艳 +4 位作者 史梦琦 蒲琴琴 胡南南 金柯 李军 《南京医科大学学报(自然科学版)》 北大核心 2026年第1期47-54,67,共9页
目的:探究多聚胞嘧啶结合蛋白2[poly(C)-binding protein 2,PCBP2]如何通过调节铁死亡参与大别班达病毒(Dabie Banda virus,DBV)感染后的致病过程及其作用机制。方法:以人单核细胞系THP-1为模型,采用qRT-PCR和Western blot技术检测DBV... 目的:探究多聚胞嘧啶结合蛋白2[poly(C)-binding protein 2,PCBP2]如何通过调节铁死亡参与大别班达病毒(Dabie Banda virus,DBV)感染后的致病过程及其作用机制。方法:以人单核细胞系THP-1为模型,采用qRT-PCR和Western blot技术检测DBV感染的THP-1细胞中PCBP2的mRNA及蛋白表达水平。通过透射电镜观察病毒感染下的线粒体结构变化,在THP-1细胞中构建了慢病毒介导的PCBP2过表达和敲低稳转细胞系。FerroOrange荧光探针检测Fe^(2+)水平,2,7-二氯荧光素二乙酸酯(2,7-dichlorofluorescein diacetate,DCFH-DA)探针测定活性氧(reactive oxygen species,ROS)水平,Western blot检测铁死亡相关溶质载体家族7成员11(solute carrier family 7 member 11,SLC7A11)和谷胱甘肽过氧化物酶4(glutathione peroxidase 4,GPX4)蛋白表达,以评估PCBP2调控对铁死亡的影响。使用铁死亡诱导剂(RSL3、erastin)和抑制剂(Fer-1、Lip-1)处理细胞,qRT-PCR和免疫荧光检测病毒复制水平变化,探索PCBP2是否可以通过调控铁死亡影响DBV复制。结果:在DBV感染的细胞模型中,PCBP2的mRNA和蛋白表达水平显著下调,DBV感染诱导典型铁死亡特征(线粒体嵴减少、肿胀)。通过qRT-PCR和Western blot验证,PCBP2敲低和过表达的THP-1细胞系构建成功,PCBP2敲低下调了铁死亡相关基因SLC7A11和GPX4的表达,导致ROS和Fe^(2+)水平升高;相反,PCBP2过表达使得SLC7A11和GPX4的表达水平升高,ROS和Fe^(2+)的水平降低。半数组织培养感染剂量与蛋白水平的检测进一步证实:铁死亡诱导剂可部分抵消PCBP2过表达促病毒复制的效应,铁死亡抑制剂可部分逆转PCBP2敲低抑制病毒复制的效应。结论:研究发现PCBP2可以通过维持SLC7A11/GPX4系统功能抑制铁死亡,从而限制DBV复制。这不仅阐明了PCBP2在DBV感染中的调控作用,为发热伴血小板减少综合征(severe fever with thrombocytope-nia syndrome,SFTS)的发病机制提供了新见解,同时靶向PCBP2-铁死亡通路可能成为SFTS治疗的潜在策略,为抗病毒药物的研发提供新思路。 展开更多
关键词 发热伴血小板减少综合征 大别班达病毒 铁死亡 多聚胞嘧啶结合蛋白2 病毒复制
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Standards lead the high-quality development of intelligent construction in China
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作者 Cheng Zhijun 《China Standardization》 2026年第1期49-49,共1页
To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction fou... To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial). 展开更多
关键词 STANDARDS technical guidelines high quality development Ministry Housing Urban Rural Development intelligent constructionstandards replicable experience intelligent construction
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