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Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4DPG, in tumor cells

Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2,4), Fan LIAO~(2,4), Chang-qi ZHAO~2, Yong-da LIN~2, Ming-xue ZUO~(2,3,5) ~2 College of Life sciences, beijing Normal University, beijing 100875 china ~3 Key laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, china College of Life sciences Beijing Normal University Beijing 100875 China

Aim: To define the in vitro cytotoxic activities of 4-demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4DPG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4DPG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562 cell lines）. For the K562 cell line, the antiproliferation effect of 4DPG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4DPG vs 2.2.x 10（-5） mol/L for etoposide). Further, 4DPG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4DPG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4DPG. Conclusion: The cytotoxicity of 4DPG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4DPG to be a potential antitumor drug.

关键词： 4-demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

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Size and distribution of Te inclusions in detector-grade CdZnTe ingots

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Progress in Natural science:Materials International 2011年第1期21卷 66-72页

作者： Ya-dong XU~(1,2),Wan-qi JIE~1,Yi-hui HE~1,Rong-rong GUO~1,Tao WANG~1,Gang-qiang ZHA~1 1.State Key laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,china 2.School of Materials science and Engineering,Northwestern Polytechnical University,Xi'an 710072,china [a] State Key laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China [b] School of Materials science and Engineering Northwestern Polytechnical University Xi'an 710072 China

To observe the Te inclusions distribution along the axial direction of CdZnTe ingots,batches of as-grown detector-grade CdZnTe crystals grown by vertical Bridgman method,were investigated using IR transmission ***,there is not a rigorous regularity for the micron-scale Te inclusions distribution along the axial direction of CdZnTe ingots according to the measurements of the present *** size and distribution variations of Te inclusions are attributed to the growth velocity, furnace temperature situation and morphological changes at the liquid-solid interface during crystal *** mobility lifetime products were discussed in conjunction with Te ***,no strict correlations are identified between the sizes and concentrations of Te inclusions and theγ-ray spectroscopy *** defects in CdZnTe crystals,which are not visible via IR transmission imaging,potentially attribute to CdZnTe detectors performance degrades.

关键词： CdZnTe Te inclusions IR imaging crystallization interface

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Bifunctional enzyme FBPase/SBPase is essential for photoautotrophic growth in cyanobacterium Synechocystis *** 6803

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Progress in Natural science:Materials International 2008年第2期18卷 149-153页

作者： Chunlan Yan,Xudong Xu The State Key laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of sciences,Wuhan 430072,china The State Key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

From a random insertion mutant library of Synechocystis sp. PCC 6803,a mutant defective in photoautotrophic growth was obtained. The interrupted gene was identified to be slr2094 (fbp1),which encodes the fructose-1,6-biphosphatase (FBPase)/sedoheptu-lose-1,7-biphosphatase (SBPase) bifunctional enzyme (F-I). Two other independently constructed slr2094 mutants showed an identical phenotype. The FBPase activity was found to be virtually lacking in an slr2094 mutant,which was sensitive to light under mixotrophic growth conditions. These results indicate that slr2094 is the only active FBPase-encoding gene in this cyanobacterium. Inactivation of photosystem Ⅱ by interrupting psbB in slr2094 mutant alleviated the sensitiveness to light. This report provides the direct genetic evi-dence for the essential role of F-I in the photosynthesis of Synechocystis sp. PCC 6803.

关键词： FBPase Photoautotrophic growth Light sensitivity Synechocystis sp.

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Use-wear analysis confirms the use of Palaeolithic bone tools by the Lingjing Xuchang early human

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Chinese science Bulletin 2010年第21期55卷 2282-2289页

作者： LI ZhanYang 1,4 & SHEN Chen 2,3,4 1 Henan Provincial Institute of Cultural Relics and Archaeology,Zhengzhou 450000,china 2 The Joint laboratory of Human Evolution and Archaeometry,Chinese Academy of sciences,beijing 100044,china 3 The Royal Ontario Museum,Toronto ON M5S2C6,Canada 4 Oriental Archaeology Research Center of Shandong University,Jinan 250100,china Henan Provincial Institute of Cultural Relics and Archaeology Zhengzhou 450000 China Oriental Archaeology Research Center of Shandong University Jinan 250100 China The Joint laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing 100044 China The Royal Ontario Museum Toronto ON M5S2C6 Canada

During 2007-2008 excavations at the Lingjing site near Xuchang,Henan Province,dated back to around 100-80 ka ago,a large quantity of mammalian fossil remains were recovered along with a remarkable cluster of Early Modern Human(EMH) skull fragments in *** some of those animal bones were probably modified into tools.A use-wear analysis was carried out to examine the functions of modified bone *** results suggest that Lingjing bone tools were used for drilling,penetrating,and scraping animal substances,and that some might have been hafted during the *** study confirms that early existence ofintentionally-modified bone tools at human occupations of the early Late Pleistocene in northern *** discovery suggests making and use of bone tools were inevitably a part of early human behaviors and cultural development,as such of stone tools.

关键词：早期人类磨损分析旧石器时代工具许昌哺乳动物化石现代人类动物骨头

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Capped carbon nanotube-based molecular switch

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science Bulletin 2010年第13期55卷 1227-1230页

作者： ZHAO Peng1, WANG PeiJi1, ZHANG Zhong1 & LIU DeSheng2 1 School of science, University of Jinan, Jinan 250022, china 2 School of Physics, State Key laboratory of Crystal Materials, Shandong University, Jinan 250100, china School of science University of Jinan Jinan 250022 China School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

Using the Landauer formalism that combines both the non-equilibrium Green's function (NEGF) and first-principles density functional theory (DFT), the electron transport characteristics of one-dimensional molecular switching device based on the capped carbon nanotubes have been investigated. The results show that the transmission can be efficiently tuned within two orders of magnitude just by changing 0.2 nm of the tube-tube separation. Moreover, the electron transport is insensitive to the topology of the facing conformations which can improve the practical stability of the chosen system as a molecular switch.

关键词： carbon nanotube molecular switch non-equilibrium Green function density functional theory

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PREDICTION OF R IN SINTER PROCESS BASED ON GREY NEURAL NETWORK ALGEBRA

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微计算机信息 2007年第28期23卷 219-221页

作者： (School of Computer science and technology,Wuhan Uni-versity of technology,Wuhan 430070)) Wang Ai-min(Computer science department,Anyang normal college,anyangHeNan province,455000,china) Wang Aimin(Mechanical engineering department of Anyang institute oftechnology ,Anyang 455002)Song Qiang School of Computer science and technology Wuhan University of technology Wuhan 430070 Mechanical engineering department of Anyang institute of technology Anyang 455002

A grey neural network model was proposed on the basis of the *** fluctuation of data sequence is weakened by thegrey theory and the neural network is capable of processing non-linear adaptable information,and the GNN is a combination of thoseadvantages. The results reveal,the alkalinity of sinter can be accurately predicted through this model by reference to small sampleand information. It was concluded that the GNN model is effective with the advantages of high precision,less requirement of samplesand comparatively simple calculation.

关键词： alkalinity of sinter grey neural network prediction the sintering process grey model

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Assembly of gold nanoparticles with H_(10)TTPR (3a, 4, 5, 8, 9, 9a, 10, 11-octa-hydro-2H,3H-1,6,7,12-tetrathia-perylene) as the rigid cross-linker

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Chinese science Bulletin 2004年第8期49卷 789-792页

作者： SHAO Xiangfeng1,2, WANG Tongxin1, ZHANG Deqing1, XU Wei 1 & ZHU Daoben1 1. Organic Solids laboratory, Center for Molecular sciences, Institute of Chemistry, Chinese Academy of sciences, beijing 100080, china 2. Graduate School, Chinese Academy of sciences, beijing 100080, china Correspondence should be addressed to Zhu Daoben or Zhang Deqing (e-mail: dqzhang@***) Organic Solids laboratory Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100080 China

Gold nanoparticles were assembled with the rigid cross-linker, H10TTPR. The assembly process was stud-ied with the UV-vis spectroscopy and TEM. By adjusting the amount of H10TTPR added to the gold nanoparticle solutio... 详细信息

关键词：纳米金粒子集成刚性交叉连接 TEM UV-力光谱学

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Neutron Diffraction Studies of the Magnetic Structure of Ho_2Fe_9Ga_(8～x)Alx

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Chinese journal of nuclear physics 1997年第1期19卷 44-47页

作者： Chen Dongfeng Gou Cheng Sun Kai china Institute of Atomic Energy,P.O.Box 275-30,beijing 102413Yan Qiwei Zhang Panlin Shen Baogen Cheng Zhaohua State Key laboratory of Magnetism,Intstitute of Physics,the Chinese Academy of sciences,P.O.Box 603,beijing 100080 中国原子能科学院北京中科院物理所磁学国家重点实验室北京

The crystallographic and magnetic structures of Ho2Fe9Ga8～xAlx（x=2,4 and 6）arestudied by powder neutron diffraction at room *** atom fractional occupancies ofGa and AI and the atom magnetic moments of Ho and Fe are obtained by Rietveld *** magnetic structure of the phase with x=2 shows an easy-axis anisotropy and themagnetic moments of all atoms are parallel to c *** saturation magnetization and Curietemperatures of samples with x in the range 0～8 are investigated.

关键词： Neutron diffraction Magnetic structure

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Simulation Experiments of Land Surface Physical Processes and Ecological Effect over Different Underlying Surface

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地球科学进展 2004年第S1期19卷 15-20页

作者： LIU Shu-hua~(1,2), JIANG Hao-yu, HU Fei~2 LIU Hui-zhi~2 LIANG Fu-ming~1, WANG Jiang-hua~1(1. Group of Atmosphere Boundary Layer and turbulence, Ministry laboratory of Storm and Drought Flood Damage, Department of Atmospheric sciences the School of Physics Peking University, beijing 100871, china 2. State Key Laboratories of Atmosphere Physics and Chemistry, Institute of Atmospheric Physics, Chinese Academy of science, beijing 100029, china)

Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth's surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas...

关键词： Comprehensive land surface Physical process model (CLSPPM) Simulation experiment Land surface physical process Ecological effect.

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A comparative study of magnetic properties between whole cells and isolated magnetosomes of Magnetospirillum magneticum AMB-1

A comparative study of magnetic properties between whole cel...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： LI JinHua~(1,2,3),PAN YongXin~(1,3*),LIU QingSong~(3,4),QIN HuaFeng~4,DENG ChengLong~4, CHE RenChao~5 & YANG XinAn~5 1 Key laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100029,china 2 Graduate University of Chinese Academy of sciences,beijing 100049,china 3 Franco-Chinese Biomineralization and Nano-structures laboratory,beijing 100029,china 4 State Key laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100029,china 5 beijing national laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of sciences,beijing 100080,china

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment,as well as novel nano-biomaterials in biotechnological and biomedical *** carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated *** revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arranged in the form of linear fragmental *** distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic *** the whole cells,the strong intra-chain interactions and weak inter-chain interactions generate behaviors of non-interacting uniaxial single-domain ***δ-ratio is 3.0 and passes the Moskowitz *** contrast,the isolated magnetosome sample has reduced values of coercivity andδ-ratio(1.5),due to increasing three-dimensional magnetostatic interactions and collapse of magnetosome *** observations provide useful insights into applications of the biogenic magnetite(magnetosomes)in magnetic nano-materials and magnetofossils in the paleomagnetic and environmental magnetism.

关键词： Magnetospirillum magneticum AMB-1 isolated magnetosomes hysteresis loop FORC Verwey transition Moskowitz test

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