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Induced temperature-dependent DNA degradation by C60 without photoactivation

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Science Bulletin 2011年第Z2期 3100-3107页

作者： WANG Chang 1,2., LIN Yan 2., WANG Ying 3 , LIANG Yong 1,3* , MENG LingZhi 4 , ZHANG Jie 2., ZHOU QunFang 1 & JIANG GuiBin 1 1 State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental sciences, chinese {2. of sciences, Beijing 100085, china 2.Key Laboratory of Subtropical Agriculture and Environment of the Ministry of Agriculture, Huazhong Agricultural university, Wuhan 430070, china 3 School of Medicine, Jianghan university, Wuhan 430056, china 4 Department of Chemistry, Wuhan university, Wuhan 430072. china

This study shows that C60can degrade pBR32. plasmid DNA at room temperature without photoactivation. The degradation was enhanced by increasing incubation temperature, reaction time or C60concentration. We also found that superoxide radical anions （O 2.· ） were formed in the C60solution. Superoxide dismutase significantly inhibited DNA cleavage and O 2.· generation induced by C60. These results suggest that DNA cleavage was caused by the formation of reactive oxygen species induced by C60at room temperature. Furthermore, we demonstrate that the DNA degradation was significantly inhibited by acid amide chemicals such as formamide, and by increased ionic strength of the reaction solution. These results indicate that the DNA conformation stability and the surface properties of C60are important factors regulating DNA degradation. We propose that C60can bind DNA, decrease DNA conformation stability, and induce the formation of reactive oxygen species and DNA cleavage at room temperature. Our results provide a possible explanation for the genotoxicity of C60, which should be considered in future use of this particular nano-material.

关键词： C60 DNA degradation reactive oxygen species genotoxicity

基于图像信息处理的蒜核仁内DNA原位排布及其结构模型的研究

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生物化学与生物物理进展 2004年第5期31卷 432-437页

作者：蔡念胡匡祜陶伟苏万芳李防震胡应雄中国科学院生物物理研究所北京100101 北京大学生命科学院北京100080 中国计算机软件与技术总公司北京100081

真核细胞核仁内的DNA超微结构对于阐述rRNA转录位点有着重要的意义 .虽然已经有许多研究者对此提出了不同的观点 ,但是都是基于直接实验观察的 .应用电子显微镜技术和改进的NAMA UrDNA特异染色方法 ,获得蒜核仁超微结构的图像 ,提出一... 详细信息

真核细胞核仁内的DNA超微结构对于阐述rRNA转录位点有着重要的意义 .虽然已经有许多研究者对此提出了不同的观点 ,但是都是基于直接实验观察的 .应用电子显微镜技术和改进的NAMA UrDNA特异染色方法 ,获得蒜核仁超微结构的图像 ,提出一种新技术定量分析核仁中DNA原位位置 .为此 ,建立多尺度形态梯度算子方法 ,编制HEREN .CELL自动分析软件 ,从而抽取出核仁超微结构的精细轮廓 ,显示出核仁DNA的原位位置 .同时 ,提出了DNA纤丝以“花瓣包迹”模式向中心外方向放射的结构模型 .

关键词：核仁 DNA原位排布数学形态学图像信息处理 “花瓣包迹”模式

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牙鲆养殖群体遗传结构的研究

海洋学报 2004年第3期26卷 102-108页

作者：黎中宝集美大学水产学院

应用聚丙烯酰胺凝胶电泳技术研究了牙鲆养殖群体(F1代)的遗传结构.结果表明,牙鲆养殖群体具有较高的遗传多样性水平.牙鲆群体平均每位点等位基因数的变化为1 19(0 11)～1 2.(0 10).多态位点百分数的变化为14 2.%～2. 81%.期望杂合度的... 详细信息

应用聚丙烯酰胺凝胶电泳技术研究了牙鲆养殖群体(F1代)的遗传结构.结果表明,牙鲆养殖群体具有较高的遗传多样性水平.牙鲆群体平均每位点等位基因数的变化为1 19(0 11)～1 2.(0 10).多态位点百分数的变化为14 2.%～2. 81%.期望杂合度的变化为0 056(0 036)～0 057(0 033).观察杂合度的变化为0 099(0 065)～0 104(0 065).牙鲆群体间遗传分化较低,群体间分化度为0 005,表明总的遗传变异中有99 5%来自群体内,有0 5%来自群体间.群体间遗传距离和遗传一致度均值分别为0 001和0 999.群体间基因流很大,等于49 75.

关键词：牙鲆等位酶遗传结构遗传多样性遗传分化

Two crucial factors influencing quality of GaAs on Ge substrate

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chinese Physics B 2014年第4期23卷 488-491页

作者：邓闯门传玲陈达 School of Energy and Power Engineering University of Shanghai for Science and Technology State Key Laboratory of Functional Materials for Informatics Institute of Microsystem and Information TechnologyChinese Academy of Sciences

High-quality GaAs films with fine surfaces and GaAs/Ge interfaces on Ge have been achieved via molecular beam epitaxy. The influence of low temperature annealing and low temperature epitaxy on the quality of the film when GaAs is grown on a （100） 6 ° offcut towards [111] Ge substrate are investigated by analyzing and comparing the GaAs films that are fabricated via three different processes. A low temperature annealing process after high temperature annealing and a low temperature epitaxy process after the initial GaAs growth play a vital role in improving the quality of GaAs film on a Ge substrate.

关键词： molecular beam epitaxy low temperature annealing low temperature epitaxy

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盐度定义狭义性与广义性

海洋学报 2001年第2期23卷 52-56页

作者：包万友刘喜民张昊中国科学院海洋研究所山东青岛266071 山东省农业技术推广总站山东济南250100 兰开斯特大学

通过理论分析和实验验证 ,论述了“实用盐标”、“氯度盐标”定义的狭义性及应用范围 ,指出电导法和氯度法测定保守性质样品 ,数据正确 ;而测定非保守性质样品 ,测定值偏离绝对盐度Sa.笔者建议的“密度盐标”属于广义性质 ,可广泛应用... 详细信息

通过理论分析和实验验证 ,论述了“实用盐标”、“氯度盐标”定义的狭义性及应用范围 ,指出电导法和氯度法测定保守性质样品 ,数据正确 ;而测定非保守性质样品 ,测定值偏离绝对盐度Sa.笔者建议的“密度盐标”属于广义性质 ,可广泛应用于保守和非保守性质样品 .密度盐标具有的优点是 :(1 )不受样品组成变化影响 ,只与溶液质量和浮力有关 ,测定值有高度可靠性与重现性 ;(2.)测定大洋水盐度与现有实用盐度值相同 ,测定工业水盐度较实用盐度、氯度盐度值更接近绝对盐度Sa;(3)在已知溶质情况下。

关键词：盐度定义狭义广义密度盐度电导法海洋水文要素氯度法

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我国脉冲星观测研究的进展和前景

天文学进展 1999年第3期17卷 236-243页

作者：吴鑫基张晋王娜中国科学院-北京大学联合北京天体物理中心中国科学院乌鲁木齐天文站乌鲁木齐830011

介绍了脉冲星观测研究的意义，国际上所取得的重大成就和脉冲星观测最主要的技术问题。分析了我国脉冲星观测研究的现状和潜力、存在的问题和美好的前景。对正在执行的由中、澳、英合作的“利用乌鲁木齐２５ｍ射电望远镜在１８ｃｍ ... 详细信息

介绍了脉冲星观测研究的意义，国际上所取得的重大成就和脉冲星观测最主要的技术问题。分析了我国脉冲星观测研究的现状和潜力、存在的问题和美好的前景。对正在执行的由中、澳、英合作的“利用乌鲁木齐２５ｍ射电望远镜在１８ｃｍ波段上进行脉冲星脉冲到达时间的观测研究”项目，就其课题意义、接收系统的技术改造和观测灵敏度等进行了介绍。展望了ＦＡＳＴ

关键词：脉冲星观测脉冲到达时间射电望远镜

Glucose deprivation-induced IL-6 expression and release isn’t mediated through NF-κB pathway in C2.12.myocytes

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Glucose deprivation-induced IL-6 expression and release isn...

中国生理学会第2.届全国会员代表大会暨生理学学术大会

作者： Xue-Lin ZHANG~1,Min-Hao XIE~2.Fan ZHANG~1,Yan-Fang WU~3 1 Capital Institute of Physical Education,Beijing 100088,china 2.Beijing Sport university,Beijing 100084,china 3 Institute of Biophysics,chinese academy of sciences,Beijing 100101,china

＜正＞Introduction:IL-6 is a pleiotropic cytokine secreted by many different *** muscle is one of important sources of IL-6,which might have relationship with energy *** the present research,we explore the effect of glucose deprivation（GD,glucose deprivation results in low intramuscular glycogen status） on skeletal muscle-derived IL-6 expression and release,and its signaling regulation by NF-kB pathway in C2.12.myocytes in ***:（1） C2.12.mouse myoblast was differentiated into myotube.（2. Differentiated C2.12.myotubes were replaced with DMEM medium containing 4.5 g/L glucose（glucose control,GC） or DMEM medium not containing glucose（glucose deprivation,GD） for 2. ***-6 mRNA level was analyzed by Real-Time ***-6 protein level in the medium was analyzed by ELISA.（3） 2.0 nmol/L NF-κB activation inhibitor was added into medium at the condition of glucose deprivation and glucose ***-6 protein in the medium was analyzed by ELISA after 2. h *** are expressed as mean±***:（1） As compared to glucose control, glucose deprivation was able to enhance IL-6 mRNA expression,and IL-6 mRNA expression was significantly increased by glucose deprivation at 2. h（0.87±0.36 vs 2.80±0.96,P＜0.05）.（2. As compared to glucose control, glucose deprivation was able to enhance protein release,IL-6 protein level in medium was significantly increased in glucose deprivation at 2. h（12.5.38±118.62.vs 2.17.11±389.2.,P＜0.05）.（3） IL-6 protein level in glucose control + NF-κB activation inhibitor decreased compared with glucose control,but had no significantly effect（12.5.38±118.62.vs 941.46±7.09,P＞0.05）.IL-6 protein level in glucose deprivation + NF-κB activation inhibitor decreased compared with glucose deprivation,but also had no significantly effect（2.17.11±389.2. vs 2.39.02.753.52.P＞0.05）. Conclusion:（1） Glucose deprivation was able to enhance skeletal muscle IL-6 mRNA expression.（2. Glucose deprivation was able to enhance skeletal muscle-derived

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非线性控制系统可逆性改善问题研究

四川大学学报（自然科学版） 2002年第2期39卷 205-208页

作者：贺昌政肖红英四川大学工商管理学院成都610064 中国科学院数学与系统科学研究院北京100080

基于多轨线思想 ,提出了系统可逆性改善问题 ,给出了系统可逆性可改善的充要条件 .

关键词：非线性控制系统逆系统方法可逆性改善问题多轨线思想判别定理充要条件

BL Lac Objects and Unified Model

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天文研究与技术 1999年第S1期 210-212页

作者： Fan J.H. (Yunnan Observatory, The chinese academy of {2., Kunming 650011, china) (National Astronomical Observatories, The chinese academy of {2.) (Center for Astrophysics, Guangzhou Normal university, Guangzhou 510400, china e mail: jhfan@g

In this paper: 1. The assumption of the dependence of Doppler factor on the emission frequency (δ v≈δ 0 18logvv o , Fan et al. 1993, ApJ., 415, 113) is used to explain the observational differences between the radio selected BL Lac objects (RBLs) and the X Ray Selected BL lac objects (XBLs): a) Hubble relation; b) different multiwavelength correlations; c) different regions in the effective spectral index (α RO - α OX ) diagram; d) different polarization. The results suggest that RBLs and XBLs are the same. 2. From the analysis of the relation between infrared magnitude and redshift, it is proposed that the parent population of BL Lac objects should be FRI radio galaxies and FRII(G) radio galaxies showing the optical spectra of a galaxy. 3. From the superluminal motion, the assumption (δ v≈δ 0 18+logvv 0 ) is confirmed. 4. Based on the relation between polarization and Doppler factor (Fan et al. 1997a), it is proposed that the f, ratio of the beamed luminosity to the unbeamed luminosity in the source frame of OVVs/HPQs is smaller than that of BL Lac objects: f RBLs ～ 6f FSRQs .

关键词： BL Lac Objects and Unified Model