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叶酸缺乏对L02细胞增殖、凋亡及纺锤体组装检查点相关蛋白表达的影响 被引量:3
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作者 任欢欢 杨瑜 +5 位作者 徐洪宝 王忠迈 程宗 梁猛 王春景 廖亚平 《蚌埠医学院学报》 CAS 2021年第5期561-565,共5页
目的:探讨叶酸缺乏对L02细胞增殖、凋亡以及纺锤体组装检查点相关蛋白基因表达的影响及其机制。方法:用不同浓度的叶酸(200 nmol/L、20 nmol/L、0 nmol/L)培养L02细胞2周后,用倒置显微镜观察L02细胞形态;流式细胞术检测细胞周期与凋亡;C... 目的:探讨叶酸缺乏对L02细胞增殖、凋亡以及纺锤体组装检查点相关蛋白基因表达的影响及其机制。方法:用不同浓度的叶酸(200 nmol/L、20 nmol/L、0 nmol/L)培养L02细胞2周后,用倒置显微镜观察L02细胞形态;流式细胞术检测细胞周期与凋亡;CCK8测定细胞增殖情况;qRT-PCR检测Mad2、Bub1、BubR1 mRNA的表达;Western blotting检测相关蛋白Mad2、Bub1、BubR1的表达。结果:与正常对照组相比,叶酸缺乏使L02细胞出现细胞体积变大、形态不规则现象;叶酸缺乏可降低L02细胞活性(P<0.01),诱导细胞发生S期阻滞(P<0.05),促进细胞凋亡(P<0.05),上调Mad2、Bub1、BubR1 mRNA及蛋白水平(P<0.01)。结论:在L02细胞培养中,叶酸浓度为200 nmol/L时导致叶酸缺乏,SAC功能受损,细胞增殖异常,严重缺乏时导致细胞发生凋亡。 展开更多
关键词 叶酸 细胞周期 纺锤体组装检查点 非整倍体
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Overexpression of the PdpapERF109 gene enhances resistance of Populus davidiana×P.alba var.pyramidalis to Fusarium oxysporum infection
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作者 Jian Diao Mingrui Li +3 位作者 Ping Zhang cheng zong Wei Ma Ling Ma 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第6期1925-1937,共13页
The key transcription factor gene PdP apE RF109 was cloned from Populus davidiana×P.alba var.pyramidalis(Pdpap),and after overexpression of P dP ap ERF109 in transformants,the gene functions in the resistance res... The key transcription factor gene PdP apE RF109 was cloned from Populus davidiana×P.alba var.pyramidalis(Pdpap),and after overexpression of P dP ap ERF109 in transformants,the gene functions in the resistance response to Fusarium oxysporum infection.Compared with the wild Pdpap,after inoculation with F.oxysporum,the physiological and biochemical characteristics,including relative fresh weight,peroxidase activity,and the percentage of electrolyte leakage showed that,after overexpression of the PdPapERF109 gene,the transformants grew well and displayed significant resistance to F.oxysporum infection.By comparing the reactive oxygen species scavenging capacity of Pdpap plants after pathogen infection,the P dPapERF109-overexpressing plants had significantly better reactive oxygen species scavenging ability than the wild plants.Comprehensive analysis of plant morphology and various physiological and biochemical parameters showed that the overexpression of the P dpapERF109 gene significantly improved the resistance of Pdpap plants to F.oxysporum root rot.Therefore,increasing the expression of the homologous ERF109 gene can be an effective strategy to increase disease resistance in hybrid poplars. 展开更多
关键词 ERF Fusarium oxysporumtolerance Gene over-expression Genetic transformation Transcription factor
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探寻式搜索路径与搜索意图转换路径的协同分析 被引量:4
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作者 赵一鸣 程宗 陈忆金 《情报资料工作》 CSSCI 北大核心 2021年第6期82-90,共9页
[目的/意义]用户搜索路径与搜索意图转换路径协同分析是深入理解探寻式搜索行为特征的关键,本文旨在揭示搜索意图改变与搜索动作变化之间的协同关系,丰富探寻式搜索的理论体系。[方法/过程]文章采用用户实验法,招募30名用户参与探寻式... [目的/意义]用户搜索路径与搜索意图转换路径协同分析是深入理解探寻式搜索行为特征的关键,本文旨在揭示搜索意图改变与搜索动作变化之间的协同关系,丰富探寻式搜索的理论体系。[方法/过程]文章采用用户实验法,招募30名用户参与探寻式任务的搜索实验,提取用户搜索行为数据,利用问卷、访谈等方法挖掘出用户的搜索意图演进模式。[结果/结论]研究发现,根据搜索活动路径和搜索意图转换的协同规律,可分辨出探寻式搜索用户交互存在不同模式:评估型、感知型、关联型和密集型四种。用户搜索意图也体现出多义性和不充分性的特征。本研究实证检验了探寻式搜索演进过程,为挖掘更多类型的探寻式搜索行为模式提供了参考。 展开更多
关键词 探寻式搜索 搜索路径 搜索意图 意图转换 协同分析
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Mutation Testing for Integer Overflow in Ethereum Smart Contracts 被引量:4
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作者 Jinlei Sun Song Huang +3 位作者 Changyou Zheng Tingyong Wang cheng zong Zhanwei Hui 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第1期27-40,共14页
Integer overflow is a common vulnerability in Ethereum Smart Contracts(ESCs)and often causes huge economic losses.Smart contracts cannot be changed once it is deployed on the blockchain and thus demand further testing... Integer overflow is a common vulnerability in Ethereum Smart Contracts(ESCs)and often causes huge economic losses.Smart contracts cannot be changed once it is deployed on the blockchain and thus demand further testing.Mutation testing is a fault-based testing method that can effectively improve the sufficiency of a test for smart contracts.However,existing methods cannot efficiently perform mutation testing specifically for integer overflow in ESCs.Therefore,by analyzing integer overflow in ESCs,we propose five special mutation operators to address such vulnerability in terms of detecting sufficiency in ESC testing.An empirical study on 40 open-source ESCs is conducted to evaluate the effectiveness of the proposed mutation operators.Results show that(1)our proposed mutation operators can reproduce all 179 integer overflow vulnerabilities in 40 smart contracts,and the generated mutants have high compilation pass rate and integer overflow vulnerability generation rate;moreover,(2)the generated mutants can find the shortcomings of existing testing methods for integer overflow vulnerability,thereby providing effective support to improve the sufficiency of the test. 展开更多
关键词 blockchain Ethereum Smart Contracts(ESCs) integer overflow mutation testing
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A Novel Cross-Project Software Defect Prediction Algorithm Based on Transfer Learning 被引量:3
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作者 Shiqi Tang Song Huang +3 位作者 Changyou Zheng Erhu Liu cheng zong Yixian Ding 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第1期41-57,共17页
Software Defect Prediction(SDP) technology is an effective tool for improving software system quality that has attracted much attention in recent years.However,the prediction of cross-project data remains a challenge ... Software Defect Prediction(SDP) technology is an effective tool for improving software system quality that has attracted much attention in recent years.However,the prediction of cross-project data remains a challenge for the traditional SDP method due to the different distributions of the training and testing datasets.Another major difficulty is the class imbalance issue that must be addressed in Cross-Project Defect Prediction(CPDP).In this work,we propose a transfer-leaning algorithm(TSboostDF) that considers both knowledge transfer and class imbalance for CPDP.The experimental results demonstrate that the performance achieved by TSboostDF is better than those of existing CPDP methods. 展开更多
关键词 Software Defect Prediction(SDP) transfer learning imbalance class cross-project
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