Proteomic analysis of human umbilical vein endothelial cells exposed to PM<Subscript>2.5</Subscript>     

Ji Zhu  Lin-wen-si Zhu  Jin-huan Yang  Ying-ling Xu  Cui Wang  Zhuo-yu Li  Wei Mao  De-zhao Lu 《Journal of Zhejiang University. Science. B》2018,19(6):458-470

Exposure to fine ambient particulate matter (PM_2.5) is known to be associated with cardiovascular disease. To uncover the molecular mechanisms involved in cardiovascular toxicity of PM_2.5, we investigated alterations in the protein profile of human umbilical vein endothelial cells (HUVECs) treated with PM_2.5 using two-dimensional electrophoresis in conjunction with mass spectrometry (MS). A total of 31 protein spots were selected as differentially expressed proteins and identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. The results demonstrated that DNA damage and cell apoptosis are important factors contributing to PM_2.5-mediated toxicity in HUVECs. It is further proposed that PM_2.5 can inhibit superoxide dismutase (SOD) activity and increase reactive oxygen species (ROS) and malonaldehyde (MDA) production in a concentration-dependent manner. Induction of apoptosis and DNA damage through oxidative stress pathways may be one of the key toxicological events occurring in HUVECs under PM_2.5 stress. These results indicated that the toxic mechanisms of PM_2.5 on cardiovascular disease are related to endothelial dysfunction.  相似文献   

现代家庭经济活动的资源约束与新经济人假定   总被引：3，自引：0，他引：3  

刘茂松 《湖南师范大学社会科学学报》2001,30(6):65-70,87

在市场经济条件下，家庭是一个集生产、投产和消费为一体的微观经济主体，家庭的这些经济活动要耗用大量的资源，包括人力资源、物质资源和时间资源。然而资源总是有限的，存在一个配置效益问题。这样，如何合理使用资源以使家庭获得的效用达到最大，这便成为家庭经济行为合理化的一个重要命题，也是直接影响整个国民经济效果的重要因素。  相似文献   

短跗星花金龟体表元素的X射线荧光光谱检测     

孙家美  毛振伟 《科技通报》1997,13(6):410-412,418

采用Ｘ射线荧光光谱仪对体表为古铜色并有金属光泽的短跗星花金龟进行了体表（背、腹面）无损多元素定性检测。样品灰化后，对其灰又进行了多元素定性检测。结果发现，此种金龟子体表所呈现的金属光泽与虫体含有较多的Ｃｕ、Ｚｎ有关。  相似文献   

ON THE REE ACROSS THE PERMIANTRIASSIC BOUNDARY IN SOUTH CHINA     

Zhou Yaoqi Chai Chifang Mao Xueying Ma Shulan Ma Jiangguo 《中国科学院研究生院学报》1992,(2)

This paper discusses the INAA results of REE in clays atand near some Permian/Triassic boundaries of South China.It showsthat the REE patterns of boundary clays differ from those of non-boundary clays.One difference is that the boundary clays are moreenriched in LREE,with steeper slope of REE and a smaller Eu nega-tive anomaly than the non-boundary clays.Another difference is that theboundary clays show a small Ce negative anomaly,but no Ce anomalyoccurs in the non-boundary clays.From these REE patterns and some other experimental facts,it isproposed that the P/T boundary clay may be a mixed product consistingof the acidic-intermediate ash and the upper crust substance representingsputtering component,and the calculated fraction of the former andlatter is 7/3.  相似文献   

房地产企业绩效管理的问题与改进措施     

毛志皓 《科技创业月刊》2007,20(2):104-104,125

随着人力资源管理在我国企业中的广泛应用,作为其重要部分之一的绩效管理越来越被管理者所重视。然而很多企业对绩效管理的认识和运用均与其本质有所偏差。通过对房地产企业的调研,分析了现阶段房地产企业在绩效管理时所存在的问题,并提出了解决方法。  相似文献   

我国经济发展状况的聚类分析   总被引：3，自引：0，他引：3  

毛小兵 《科技广场》2007,(2):23-25

改革开放以来,我国经济取得了前所未有的快速发展,但同时也存在地区经济发展极不平衡的问题。本文利用聚类分析方法对我国31个省(直辖市、自治区)的经济发展状况进行聚类分析,探讨我国各区域之间经济发展的差异,从而为我国区域协调发展提供有效决策的依据。  相似文献   

智力资本度量的记分卡方法评述   总被引：11，自引：0，他引：11  

武志伟  茅宁 《科研管理》2003,24(4):46-53

知识经济时代,企业的价值关键在于其拥有的智力资本,对智力资本实施有效的管理对于企业建立持久的竞争优势至关重要。但智力资本的管理离不开对智力资本的度量,只有明确企业现有智力资本存量的基础上,才可能真正地对智力资本实施有效的管理。本文简单介绍了一类智力资本度量方法——记分卡方法中各个模型的基本思路和使用方法。  相似文献   

智慧阅读服务概念界定及国内相关研究评析     

茆意宏  朱玲玲  韩燕 《图书情报工作》2020,64(1):131-138

[目的/意义] 对智慧阅读服务概念进行界定,梳理国内近3年的相关研究成果,为该领域的研究发展提供参考。[方法/过程] 在CNKI对2017年以来国内的相关研究成果进行检索,梳理相关研究文献,分析研究热点,归纳智慧阅读服务的分析框架,并对未来的研究进行展望。[结果/结论] 2017年以来国内智慧阅读服务研究成果主要包括智慧阅读服务系统与平台、用户、服务内容与策略、服务评价、服务管理等,智慧阅读服务内容与策略、用户是其中两个研究热点方向,研究较多的热点信息技术是大数据与人工智能技术、虚拟现实技术。智慧阅读服务将是未来的研究热点,技术与用户是未来研究的重点方向。  相似文献   

Effects of osmotic stress on antioxidant enzymes activities in leaf discs of P<Subscript>SAG12</Subscript>-<Emphasis Type="Italic">IPT</Emphasis> modified gerbera     

Lai QX  Bao ZY  Zhu ZJ  Qian QQ  Mao BZ 《Journal of Zhejiang University. Science. B》2007,8(7):458-464

Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance （TBARS） and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant （wild type）. Leaf discs were incubated in 20%, 40% （w/v） polyethylene glycol （PEG） 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/（m^2·s）]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase （SOD）, catalases （CAT）, ascorbate peroxidase （APX）, guaiacol peroxidase （GPX） and dehydroascorbate reductase （DHAR） were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation （TBARS content） was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress.  相似文献   

在线社区用户承诺影响因素研究：一项元分析     

朱玲玲  茆意宏 《图书情报工作》2023,67(3):106-118

[目的 /意义]对在线社区用户承诺影响因素的相关实证研究进行梳理和再分析,以解释影响在线社区用户承诺的一般性因素,为后续研究提供参考。[方法 /过程]运用元分析方法,选取以用户承诺为研究主题、以在线社区为研究情境的文献作为样本文献,归纳和识别在线社区的用户承诺影响因素,并进一步探索影响异质性的调节变量。[结果 /结论 ]显著影响在线社区用户承诺的因素包括系统外部、需求动机及用户感知三个类别的10个变量,与在线社区用户承诺为中度相关关系的有情感依恋、信息性动机、感知娱乐性、信息质量,而社交动机、社会互动、满意度、信任、感知收益、社区认同与用户承诺高度相关。在线社区类型会对情感依恋、社会互动、感知娱乐性等变量与用户承诺之间的关系产生调节。研究结果对未来深入研究和不同情境研究具有借鉴意义,也对在线社区运营具有实践指导作用。  相似文献