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Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, beijing 100049, china 2. College of Chemistry and Molecular Engineering, peking university, beijing 100871, china 3. department of Occupational and Environmental Health Sciences, School of Public Health, peking university, beijing 100083, china Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China department of Occupational and Environmental Health Sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Internalization and distribution of three α1-adrenoceptor subtypes in HEK293. cells before and after agonist stimulation

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Acta Pharmacologica Sinica 2007年第3期28卷 359-366页

作者： Shu-yi WANG~2 Yao SONG~2 Ming XU~2 Qi-hua HE~3.Qi-de HAN~2 You-yi ZHANG~(2,4)2 Institute of Vascular Medicine,peking university third hospital and Key Laboratory of Molecular Cardiovascular Sciences,Ministry of Education,{3. 100083,china 2 Center of Medical Analysis,peking university,Health Science Center,{3. 100083,china Institute of Vascular Medicine Peking University Third Hospital and Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing China Center of Medical Analysis Peking University Health Science Center Beijing China

Aim:To examine the subcellular distribution of the 3.α1-adrenoceptor（α1-AR）subtypes and their internalization and trafficking upon agonist stimulation in hu-man embryonic kidney 293. ***:Confocal real-time imaging,enzymelinked immunosorbent assay（ELISA）and whole cell[3.]-prazosin binding assaywere applied to detect the distribution and localization of the 3.α1B-AR ***:α1A-AR was found both on the cell surface and in the cytoplasm;α1B-AR,however,was predominantly detected on the cell surface,while α1D-AR wasdetected mainly in the intracellular *** stimulation withphenylephrine,localization changes were detected by confocal microscopy forα1A-and α1B-AR, but the localization of α1D-AR were *** promoted a more rapid internalization of α1B-AR than α1A-AR.α1D-ARinternalization was detected only by *** cell[3.]-prazosin bindingassay showed that α1A-AR functional receptors were detected both on the cellsurface and in the cytoplasm;α1B-AR,however,were detected predominantly onthe cell surface,while α1D-AR were detected mainly in intracellular *** stimulation promoted internalization of α1A-and α***:Phenylephrine stimulation induced changes in the localization of the3.1-AR.

关键词： adrenoceptor agonist stimulation confocal image enzyme-linked immunosorbent assay [~3.]-prazosin binding assay internalization subcellular distribution subtype

L~∞ CONVERGENCE OF QUASI-CONFORMING FINITE ELEMENTS FOR THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 1995年第2期13卷 108-122页

作者： Wang Ming (department of Mathematics, peking university, beijing,{3.) 北京大学数学系北京

In this paper we consider the L∞ convergence for quasi-conforming finite ele-ments solving the boundary value probzlems of the biharmonic equation and give the nearly optimal order L∞ estimates.

关键词：双调和方程拟共形有限元 L↑∞收敛性 L↑∞估计

Oblique Derivative Problems for Second OrderNonlinear Equations of Mixed Type inMultiply Connected Domains

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Communications in Nonlinear Science and Numerical Simulation 1999年第4期4卷 281-284页

作者： Guochun WEN(department of Mathematics, peking university, beijing 100871,{3.) department of Mathematics Peking University Beijing 100871 China

1FormulationoftheProblemLetDbeNconnectedboundeddomaininthecomplexplaneCwiththeboundaryNZNOD=WUL,wherer=ZrjEn（00},L=ULi’andrhastheendj=1j=1poiatsal=0 详细信息

1FormulationoftheProblemLetDbeNconnectedboundeddomaininthecomplexplaneCwiththeboundaryNZNOD=WUL,wherer=ZrjEn（00},L=ULi’andrhastheendj=1j=1poiatsal=0

关键词： oblique derivative problems quasinonlinear equations of mixed type mul-tiply connected domains.

Enhancement of cardiomyocyte differentiation from human embryonic stem cells

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Science china(Life Sciences) 2010年第5期53卷 581-589页

作者： WANG YanXia1,2,CHEN GuiAn1,2,SONG TianRan1,2,MAO GenHong1,2 & BAI HaiYan1,2 1Reproductive Medicine Center,peking university third hospital,{3. 100083,china 2Stem Cell Research Center,peking university third hospital,{3. 100083,china Reproductive Medicine Center Peking University Third Hospital Beijing China Stem Cell Research Center Peking University Third Hospital Beijing China

Several approaches have been used to encourage the differentiation of cardiomyocytes from human embryonic stem ***,the differentiation efficiency is low,and appropriate culture protocols are needed to produce adequate numbers of cardiomyocytes for therapeutic cell *** study investigated the effects of serum on cardiomyocyte differentiation in suspension culture medium during embryoid body(EB) formation by human embryonic stem *** addition of ascorbic acid,dimethylsulfoxide and 5-aza-2'-deoxycytidine during days 5-7 at the EB-forming stage resulted in an increase in the numbers of rhythmically contracting clusters of derived *** with 0.1 mmol L-1 ascorbic acid alone,or more notably in combination with 10 μmol L-1 5-aza-2'-deoxycytidine,induced the formation of beating cells within *** of the beating clusters had spontaneous contraction rates similar to those found in human adults,and their contractile ac-tivity lasted for up to 194 days.

关键词： human embryonic stem cells cardiomyocyte differentiation serum ascorbic acid 5-aza-dC

CALCULATING MODELS OF MASS ACTION CONCENTRATIONSFOR MATTES (Cu_2S-FeS-SnS)INVOLVING EUTECTIC

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 392-397页

作者： J. Zhang (department of Metallurgy, university of Science and Technology beijing,{3., china) Univ of Science and Technology Beijing Beijing China

Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts and basic oxide solid solutions, the calculating models of mass action concentrations for binary and ternary mattes involving eutectic have been formulated. The results of calculation agree well with the values measured;this in turn shows that the calculating models can reftect the structural characteristics of the mattes concerned.

关键词： matte activity eutectic mass action concentration

Implantable CMOS neuro-stimulus chip for visual prosthesis

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Science china(Information Sciences) 2011年第4期54卷 898-908页

作者： ZHANG Xu 1,PEI WeiHua 1,HUANG BeiJu 1,WANG ShuJing 1,GUAN Ning 1,GUO Kai 1,WANG Yu 1,GUI Qiang 1,CHEN Jin 1,WANG Kai 2,WU HuiJuan 2,LI XiaoXin 2,LI Kai 3.& CHEN HongDa 1 1 State Key Laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,beijing 100083,china 2 {3. of Ophthalmology,People’s hospital of peking university,beijing 100044,china 3.{3. of Epidemiology and Biostatistics,Health Science Center,peking university,beijing 100083,china State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China department of Ophthalmology People’s Hospital of Peking University Beijing China department of Epidemiology and Biostatistics Health Science Center Peking University Beijing China

A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pixel integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3.bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.18-μm N-well CMOS (complementary metal oxide semiconductor) 1P6M Mix-signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex- periment electrical evoked potential (EEP) test

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of Chemistry, Qingdao university, Qingdao 266071, china 2. department of Chemistry, Tsinghua university, beijing 100084, china 3. department of Physics, Qingdao university, Qingdao 266071, china department of Chemistry Qingdao University Qingdao China department of Chemistry Tsinghua University Beijing China department of Physics Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Prevention and treatment of hepatitis B recurrence after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2003年第4期2卷 500-503页

作者： Jian-Ping Zhu Tong-Lin Zhang Lei Li Jiong Yuan Shi-Bing Song Dian-Rong Xiu Kuan-Yong Hou Tong Li Hui Zhuang From the department of surgery, third hospital of{3., beijing 100083, china department of Microbiology,{3. Health Science Center, beijing 100083, china department of surgery Third Hospital of Peking University Beijing 100083 China. zhujianpingwz@***

OBJECTIVE: To study the efficacy of liver transplantation on end-stage hepatitis B related liver diseases, and the prevention and treatment strategies of hepatitis B recurrence after the transplantation. METHODS: The efficacy of combined treatment of lamivudine and hepatitis B immune globulin (HBIG) therapy on 24 patients who had received liver transplantation was retrospectively studied. RESULTS: All the 24 patients with end-stage hepatitis B-related liver diseases treated with lamivudine alone or combined therapy of lamivudine and HBIG showed normal liver function and 21 of them lost hepatitis B virus (HBV) markers. However, the remaining 3.patients became HBsAg positive again soon after liver transplantation. CONCLUSIONS: Liver transplantation is effective for patients with end-stage hepatitis B-related liver diseases. Combined treatment of lamivudine and HBIG may prevent the recurrence of hepatitis B after the operation.

关键词： liver transplantation hepatitis B virus hepatitis B recurrence lamivudine hepatitis B immune globulin