45 research outputs found

    Surface Electrochemical Studies of Ferrocene and Its Interaction with DNA

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    在研究碳纳米管电极上二茂铁电化学性质的基础上,应用二茂铁修饰电极和DNA修饰电极研究了二茂铁与小牛胸腺DNA的相互作用。结果表明,修饰电极上的二茂铁都呈现一对明显的氧化还原峰,二茂铁修饰电极与DNA的作用表现为氧化还原峰电流减小,与溶液中的两者作用情况类似,而DNA修饰电极与二茂铁的作用则表现为氧化还原峰电流增大。扫描电镜结果也证实了两种修饰电极上的二茂铁与DNA间的作用。此外,还讨论了二茂铁与DNA间的作用模式。The interaction of ferrocene with calf thymus DNA has been investigated by using the ferrocene and/or DNA modified electrodes based on the electrochemical properties of ferroceneon on the carbon nanotube_modified electrode. The results show that an obvious redox peak for ferrocene is exhibited on the modified electrode. There exists a decrease for the redox peak currents on the electrode modified by ferrocene in the presence of DNA, which is similar to their interaction in solution. However, when the electrode modified by DNA is used as the working electrode, the redox peak current appears an increase compared with that by using the carbon nanotube_modified electrode. The interaction between ferrocene and DNA is also proved by SEM. In addition, the interaction mode of ferrocene with DNA is discussed.广东省教育厅自然科学基金(Z03020);; 广州市科委(2004J1-C0091)资助项

    南极海冰区冰藻类群及兴衰过程

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    本文总结了国际上对南极冰藻类群及其生理生态特性的多年研究成果 ,结合我国科学家在南极长城站以及在戴维斯和中山站的越冬研究 ,阐述了南极海冰区的冰藻类群及其形成机理 ,对冰藻的形成、存活、旺发和消亡过程进行讨论 ,并对大洋浮冰区和近岸固定冰区冰藻类群的生态特性进行对比 ,提出了今后有待进一步深入研究的领域 【英文摘要】 Combining with the research results obtained from the Great Wall and Zhongshan Stations of China, the thesis reviews the different ice algal assemblages occurring in the Antarctic sea ice and their formation, survival, growth and disappearance, compares the difference between the pack and fast sea ice zones and brings forward some scientific questions which are needed for further research. There are surface, interior, bottom and sub ice assemblages within ice, and each composes of some types. Because of ...国家自然科学基金项目 ( 30 2 70 112 ;4 0 0 0 6 0 10 )资

    The progress in the study of Arctic pack ice ecology

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    The sea ice community plays an important role in the Arctic marine ecosystem. Because of the predicted environmental changes in the Arctic environment and specifically related to sea ice, the Arctic pack ice biota has received more attention in recent years using modern ice-breaking research vessels. Studies show that the Arctic pack ice contains a diverse biota and besides ice algae, the bacterial and protozoan biomasses can be high. Surprisingly high primary production values were observed in the pack ice..

    旋转玻碳电极上二茂铁的电化学阻抗行为及其与DNA的相互作用

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    应用旋转圆盘电极和电化学阻抗法研究了二茂铁在Tris-NaC l(pH=7.2)缓冲溶液中于旋转玻碳电极上的电化学阻抗行为及其与DNA的相互作用.结果表明,二茂铁于旋转电极的伏安曲线呈现明显的极限电流平阶,而其交流阻抗谱则出现两个电容弧.二茂铁与DNA的作用,若受扩散过程控制则其极限扩散电流随DNA浓度增大而减小,而在电化学控制过程中则表现为电化学反应电阻随DNA浓度增大而增大.根据旋转圆盘电极和电化学阻抗谱测试,表明由这两种方法数据拟合求得的二茂铁条件电位速率常数能够很好地相互吻合,但如存在DNA时,则其条件电位速率常数有一定程度的减小

    Expression and Localization of hnRNP A2/B1 during Differentiation of Human Osteosarcoma MG-63 Cells Induced by HMBA

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    背景与目的:核基质蛋白的差异表达与细胞癌变和增殖分化调控关系密切。本研究观察了hnRNP A2/B1在诱导分化处理前后人成骨肉瘤MG-63细胞核基质中的存在和分布,及其与Actin、Prohibitin的共定位关系。方法:选择性抽提经环六亚甲基双乙酰胺(hexamethylene bisacetamide,HMBA)诱导处理前后的MG-63细胞核基质,并运用双向电泳、质谱分析、蛋白质印记杂交、免疫荧光、激光共聚焦等技术检测hnRNP A2/B1在核基质中的表达与定位变化,及其与相关蛋白的共定位关系。结果:双向电泳及蛋白质印迹杂交结果证实了hnRNP A2/B1存在于MG-63细胞核基质蛋白组分中,并在HMBA处理后细胞核基质中表达下调;免疫荧光显微镜观察显示hnRNP A2/B1定位在核基质上,经HMBA处理后hnRNP A2/B1表达减弱。激光共聚焦显微镜观察结果显示,hnRNP A2/B1与细胞核基质蛋白组分Actin、细胞增殖相关调控因子Prohibitin具有共定位关系,但在诱导处理后细胞内的共定位关系减弱。结论:hnRNP A2/B1在MG-63细胞诱导分化过程中的表达分布,及其与Actin、Prohibitin的共定位关系的改变对MG-63细胞分化具有重要影响,值得进一步探索和研究。BACKGROUND & OBJECTIVE: The differentially expressed nuclear matrix proteins have great effects on canceration and regulation of cell differentiation. This study was to explore the existence and distribution of ribonucleoprotein hnRNP A2/B1 in nuclear matrix and its co-localization with Actin and Prohibitin in human osteosarcoma MG-63 cells before and after hexamethylene bisacetamide (HMBA) treatment. METHODS: The nuclear matrix of MG-63 cells before and after treatment of HMBA were selectively extracted. The expression and localization of hnRNP A2/B1 in nuclear matrix were detected by 2-D PAGE, MALDI-TOF-MS, Western blot, and immunofluorescent staining. The co-localization of hnRNP A2/B1 with Actin and Prohibitin was observed under laser scanning confocal microscope (LSCM). RESULTS: hnRNP A2/B1 was detected in the component of nuclear matrix proteins of MG-63 cells by Western blot and immunogold staining and its expression was decreased after treatment of HMBA. hnRNP A2/B1 was located in the nuclear matrix, and its expression was weakened after HMBA treatment. hnRNP A2/B1 was co-localized with Actin or Prohibitin in MG-63 cells, while the co-localization relationship was weakened during differentiation of MG-63 cells. CONCLUSIONS: hnRNP A2/B1 is a kind of nuclear matrix protein, and localizes in the nuclear matrix. The distribution and expression of hnRNP A2/B1 and its co-localization with Actin and Prohibitin play important roles during the differentiation of MG-63 cells.国家自然科学基金项目(No.30470877)~

    应用调整的膳食平衡指数评价厦门市区成年居民膳食质量

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    目的利用调整的中国膳食平衡指数(dbI-07)综合评价厦门市城区18~65岁居民膳食质量,为开展营养干预提供依据。方法采用多阶段分层整群抽样方法于2010年10—12月对厦门市区6个社区居委会成年居民进行调查,采用连续3天24 H回顾法对其中的520人进行了膳食调查,采用dbI-07的评分方法评价厦门城区成年居民膳食质量水平。结果被调查的厦门市城区成年居民的膳食质量处于中度失衡状态,摄入不足和摄入过量并存;女性的摄入不足程度高于男性;各年龄段中,40~50岁人群摄入不足程度最高,摄入过量程度最低。结论被调查的厦门市城区成年居民水果、奶类及豆类摄入不足,肉类、食用油及盐类摄入过量;成年居民的主要膳食模式为A模式,且A模式反映了膳食中摄入不足与摄入过量的问题均较少,为最优模式。中央财政转移支付地方项

    学校流感暴发疫情防控措施动力学模型效果分析

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    目的探讨学校流感暴发疫情的最佳控制方式,为制定停课标准提供参考。方法通过SEIAR模型对流感暴发疫情隔离和停课效果进行分析。结果本起流感暴发疫情基本再生数R0为7.6180,无干预措施下疫情会持续20天,1 169名学生和教职工(99.74%)会感染流感。第5~10天开始隔离措施,疫情持续时间介于35~44天,第10天开始隔离感染人数是第5天开始隔离的6.9倍。与单独采取隔离措施相比,停课1天、3天、5天、7天可以减少4.51%~10.92%、13.41%~29.31%、19.46%~45.40%和24.82%~57.47%的感染人数,持续时间并没有太大变化;停课14天疫情持续时间都会明显下降,感染人数下降33.43%~65.52%。结论隔离措施越早实施对疫情控制效果越好,显性感染人数达到20%以上时可以停课,出现重症或死亡病例时要将停课时间延长

    ——记享受国务院政府特殊津贴专家李冠盛馆长

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    采访图书馆李冠盛馆长在图书馆自动化、网络化、数字化建设的历程

    藻类的生物控制技术研究进展

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    大面积的藻类暴发,严重破坏了水生生态系统的平衡与稳定,给人类的生产和生活造成了极大影响,而且藻毒素已构成对人类生存环境的威胁。生物控藻是一种生态修复技术,它借助于溶藻细菌、水生植物分泌的化感物质、滤食藻类的微小动物以及鲢鱼和鳙鱼等滤食性鱼类对藻类的共同作用,从而达到控制藻类生长的目的。本文概述了藻类生物控制技术的研究进展,并对该技术今后的发展方向进行了展望
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