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Protein & Cell 2015年第12期6卷 919-923页

作者： Jia Wang (1) (2) (3) Weiguang Wang (1) (2) Wen Song (2) (3) (4) Zhifu Han (2) (3) (4) Heqiao Zhang (2) (3) (4) Jijie Chai (2) (3) (4) Hongwei Wang (2) (3) (4) Jiawei Wang (1) (2) 1.State Key Laboratory of Membrane Biology School of Life Sciences Tsinghua University Beijing 100084 China 2.Center for Structural Biology School of Life Sciences Tsinghua University Beijing 100084 China 3.Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China 4.Ministry of Education Key Laboratory of Protein Science School of Life Sciences Tsinghua University Beijing 100084 China

Cryo-electron microscopy （cryo-EM） and macromolecular crystallography （MX） both allow the creation of three-dimensional images of biological macromolecules. EM data usually provide access to three-dimensional reconstructions of large biological complexes at low resolution, whereas MX usually delivers atomic or quasi-atomic resolution structures （1-3 A）.

关键词： Phase Error Molecular Replacement Histogram Match TLR13 Molecule Solvent Flatten

Biofilm inhibition and corrosion resistance of 2205-Cu duplex stainless steel against acid producing bacterium Acetobacter aceti

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Journal of Materials Science & Technology 2019年第11期35卷 2494-2502页

作者： Dan Liu Ru Jia Dake Xu Hongying Yang Ying Zhao Msaleem Khan Songtao Huang Jiankang Wen Ke Yang Tingyue gug School of Metallurgy Northeastern UniversityShenyang110819China Mary Kay O'Connor Process Safety Center Artie McFerrin Department of Chemical EngineeringTexas A&M UniversityCollege StationTX 77843USA Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518055China Institute of Metal Research Chinese Academy of SciencesShenyang110016China General Research Institute for Nonferrous Metals Beijing100088China Department of Chemical and Biomolecular Engineering Institute for Corrosion and Multiphase TechnologyOhio UniversityAthensOH 45701USA

Acid producing bacterium Acetobacter aceti causes pitting corrosion of stainless steel(SS).This work investigated the enhanced resistance of 2205-Cu duplex stainless steel(DSS)against biocorrosion by *** in comparison with 2205 DSS using electrochemical and surface analysis *** the addition of Cu to 2205 DSS,biofilms on the 2205-Cu DSS surface were inhibited *** largest pit depth on 2205-Cu DSS surface in the presence of A aceti was 2.6μm,smaller than 5.5μm for 2205 DSS *** i(corr)was 0.42±0.03μA cm^-2 for 2205-Cu DSS in the biotic medium,which was much lower than that for 2205 DSS(3.69±0.65μA cm^-2).All the results indicated that the A aceti biofilm was considerably inhibited by the release of Cu^2+ions from the 2205-Cu DSS matrix,resulting in the mitigation of biocorrosion by A aceti.

关键词： Duplex stainless steel Acid producing bacteria Microbiologically influenced corrosion Pitting corrosion

Preparing a re-sequencing DNA library of 2 cancer candidate genes using the ligation-by-amplification protocol by two PCR reactions

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Science China(Life Sciences) 2009年第5期52卷 483-491页

作者： SU YeYang1,2,3, LIN Lin1,2,3, TIAN Geng1,2,3, CHEN Chen2,3, LIU Tao2,3, XU Xingya3, QI XinPeng1,2,3, ZHANG XiuQing2,3& YANG HuanMing2,3 1 Graduate School of Chinese Academy of Sciences, Beijing 100049, China 2 Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100029, China 3 Beijing Genomics Institute, Beijing 101300, China Graduate School of Chinese Academy of Sciences Beijing 100049 China Beijing Institute of Genomics Chinese Academy of Sciences Beijing 100029 China Beijing Genomics Institute Beijing 101300 China

To meet the needs of large-scale genomic/genetic studies, the next-generation massively parallelized sequencing technologies provide high throughput, low cost and low labor-intensive sequencing service, with subsequent bioinformatic software and laboratory methods developed to expand their applications in various types of research. PCR-based genomic/genetic studies, which have significant usage in association studies like cancer research, haven't benefited much from those next-generation sequencing technologies, because the shortgun re-sequencing strategy used by such sequencing machines as the Illumina/Solexa Genome Analyzer may not be applied to direct re-sequencing of short-length target regions like those in PCR-based genomic/genetic studies. Although several methods have been proposed to solve this problem, including microarray-based genomic selections and selector-based technologies, they require advanced equipment and procedures which limit their applications in many laboratories. By contrast, we overcame such potential drawbacks by utilizing a ligation by amplification (LBA) protocol, a method using a pair of Universal Adapters to randomly ligate target regions in a two-step-PCR procedure, whose Long LBA products were easily fragmented and sequenced on the next-generation sequencing machine. In this concept-proven study, we chose the consensus coding sequences of two human cancer genes: BRCA1 and BRCA2 as target regions, specifically designed LBA primer pairs to amplify and randomly ligate them. 70 target sequences were successfully amplified and ligated into Long LBA products, which were then fragmented to construct DNA libraries for sequencing on both a conventional Sanger sequencer ABI 3730xl DNA Analyzer and the next-generation 'synthesis by sequencing technology' Illumina/Solexa Genome Analyzer. Bioinformatic analysis demonstrated the utility and efficiency (including the coverage and depth of each target sequence and the SNPs detection effectiveness) o

关键词： health genomics the next-generation sequencing techonology sequencing technology large-scale genomics PCR

Anticancer effect of two diterpenoid compounds isolated from Annona glabra Linn

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Acta Pharmacologica Sinica 2004年第7期25卷 91-96页

作者： Yong-hong ZHANG2, Hai-yan PENG3, Guo-hao XIA3, Ming-yan WANG3, Ying HAN4 First Clinical College 3Basic Medicine College, Nanjing University of TraditionalChinese Medicine, Nanjing 210029 4Jiangsu Institute of Materia Medica, Nanjing 210009, China First Clinical College Basic Medicine College Nanjing University of Traditional Chinese Medicine Jiangsu Institute of Materia Medica

AIM: To study the inhibitory effect of two diterpenoid compounds isolated from Annona glabra Linn (Cunabic acid and ent-kauran-19-al-17-oic acid) on the proliferation of Human Liver Cancer (HLC) cell line SMMC-7721 and its mechanism. METHODS: Inhibition of cell proliferation was measured by MTT assay. The morphological changes of SMMC-7721 cells were observed under inverted phase-contrast microscope, fluorescent microscope, transmission electron microscope (TEM), and scanning electron microscope (SEM). Flow cytometer (FCM) was used to calculate the cell apoptotic rate, and immunohistochemical staining was used to observe the regulation of gene expression. RESULTS: The proliferation of SMMC-7721 cells was obviously inhibited after being treated with Cunabic acid at the concentration >5 μmol/L and ent-kauran-19-al-17-oic acid >10 μmol/L. The biggest inhibitory effect was 81.05 % when treated with Cunabic acid at the concentration of 25 μmol/L. The effect had a linear relationship with concentration. The result indicated that drug-treated cells exhibit typical morphological changes of apoptosis, including condensed chromatin and a reduction in volume. Sub-G0/G1 peak was found by FCM analysis and the cell cycle was arrested at G0/G1 stage. The apoptotic rates of the cells treated by Cunabic acid and ent-kauran-19-al-17-oic acid were 43.31 % and 24.95 %, respectively. It was visualized by immunohis- tochemical staining that the drugs down-regulated the gene expression of bcl-2 gene and up-regulated that of bax gene. CONCLUSION: The two diterpenoid compounds isolated from Annona glabra Linn, Cunabic acid and ent- kauran-19-al-17-oic acid can obviously inhibit the proliferation of HLC cell line SMMC-7721. The mechanism is correlated with the induction of cell apoptosis by down-regulating the gene expression of bcl-2 gene and up- regulating that of bax gene.

关键词： Annona glabra Linn diterpenes hepatocellular carcinoma apoptosis gene expression

Design of a 400 N and 12 mm Mechanical Air Gap High Temperature Superconducting Linear Synchronous Motor

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稀有金属材料与工程 2011年第S3期40卷 319-321页

作者： Yen Fei1,2,3, Li Jing1,2,3, Zheng Shijun1,2,3, Jiang Donghui1,2,3, Liu Lu1,2,3, Liu Wei1,2,3, Ma Guangtong1,2,3, Wang Jiasu1,3, Wang Suyu1,3 1 Applied Superconductivity Laboratory, Southwest Jiaotong University, Chengdu 610031, China 2 State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China 3 National Laboratory for Rail Transit, Chengdu 610031, China SW Jiaotong Univ Appl Superconduct Lab Chengdu 610031 Peoples R China SW Jiaotong Univ State Key Lab Tract Power Chengdu 610031 Peoples R China Natl Lab Rail Transit Chengdu 610031 Peoples R China

The static thrust output on a superconducting coated conductor coil at different excitation and alternating current suspended above a three phase alternating current long-stator comprised of copper coils is presented. Excitation current up to 45 A was applied through the superconducting coil acting as the excitation system of the superconducting linear synchronous motor (SLSM), alternating current up to 9 A was applied to the armature and magnetic air gaps of 10 and 15 mm were investigated for four different cases; coreless, with an iron core or yoke and both a core and yoke. By scaling up and converting the studied superconducting single pancake racetrack coil into a double pancake coil and connecting four of such coils in series, an SLSM prototype capable of generating 400 N of thrust output and 1 kW of power output with a 12 mm mechanical air gap operating at 77 K is proposed.

关键词： high temperature superconductivity linear synchronous motor long stator motor superconducting coil force measurements

Complex dynamic behaviors of a discrete predator-prey model with stage structure and harvesting

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International Journal of Biomathematics 2017年第1期10卷 233-257页

作者： Boshan Chen 3iejie Chen College of Mathematics and Statistics Hubei Normal UniversityHuangshi 435002 Hubei P. R. China College of Computer Science and Technology Hubei Normal University Huangshi 435002 Hubei P. R. China

First, a discrete stage-structured and harvested predator-prey model is established, which is based on a predator-prey model with Type III functional response. Then the~ oretical methods are used to investigate existence of equilibria and their local proper- ties. Third, it is shown that the system undergoes flip bifurcation and Neimark-Sacker bifurcation in the interior of R~_, by using the normal form of discrete systems, the center manifold theorem and the bifurcation theory, as varying the model parameters in some range. In particular, the direction and the stability of the flip bifurcation and the Neimark -Sacker bifurcation are showed. Finally, numerical simulations are presented not only to illustrate our results with the theoretical analysis, but also to exhibit the com- plex dynamical behaviors, such as cascades of period-doubling bifurcation and chaotic sets. These results reveal far richer dynamics of the discrete model compared with the continuous model. The Lyapunov exponents are numerically computed to confirm fur- ther the complexity of the dynamical behaviors. In addition, we show also the stabilizing effect of the harvesting by using numerical simulations.

关键词： Stability flip bifurcation Neimark-Sacker bifurcation chaos discrete dyna-mical system predator-prey model harvesting.

Anisotropic HDDR-treated Nd_2Fe_(14)B-type powder

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Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1590-1593页

作者： LIU Min1,3,HAN BaiPing2,3,HAN GuangBing3 & GAO RuWei3 1 Department of Electronic Science,Huizhou University,Huizhou 516007,China 2 College of Mathematical and Physical Sciences,Xuzhou Institute of Technology,Xuzhou 221008,China 3 School of Physics,Shandong University,Jinan 250100,China 1. Department of Electronic Science Huizhou University Huizhou 516007 China3. School of Physics Shandong University Jinan 250100 China2. College of Mathematical and Physical Sciences Xuzhou Institute of Technology Xuzhou 221008 China

Effects of the wheel speeds v and disproportionation time during the SC-HDDR process on the properties of Nd-Fe-B magnetic powders are *** is found that the remanence Br,coercivity Hcj and energy products(BH)max of magnetic powders all first increase to the maximum at v=3 m/s,and then decrease with enhancing *** is attributed to the fact that the SC alloy flakes prepared by the wheel speed of 3 m/s display the optimized *** optimized SC alloy flakes without homogenizing treatment which carried out a short duration disproportionation treatment can prepare the evidently anisotropic *** prolonging disproportionation time,the alignment degree of anisotropy of magnetic powders gradually *** is due to the fact that a short duration disproportionation reaction is beneficial to the disproportionated microstructure displaying the lamella crystals,and the lamella disproportionated microstructure is helpful to the formation of *** results confirm that the anisotropic HDDR Nd-Fe-B magnetic powders prepared directly from the SC alloy flakes without homogenizing treatment can be obtained.

关键词： SC-HDDR process SC alloy flakes disproportionated microstructure anisotropic powders

Pre-LOI trajectory maneuvers of the CHANG'E-2 libration point mission

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Science China(Information Sciences) 2012年第6期55卷 1249-1258页

作者： WU WeiRen 1,LIU Yong 2,3,LIU Lei 2,3,ZHOU JianLiang 3,TANG GeShi 2,3 & CHEN YongZhi 3 1 Chinese Lunar Exploration and Space Project Center,Beijing 100037,China 2 Science and Technology on Aerospace Flight Dynamics Laboratory,Beijing 100094,China 3 Beijing Aerospace Control Center,Beijing 100094,China 1. Chinese Lunar Exploration and Space Project Center Beijing 100037 China2. Science and Technology on Aerospace Flight Dynamics Laboratory Beijing 100094 China3. Beijing Aerospace Control Center Beijing 100094 China

This paper addresses pre-LOI (before Lissajous orbit insertion) trajectory maneuvers for the libration point mission of CHANG'E-2,which is the first Chinese satellite to fly to the Sun-Earth L2 libration point and the first satellite ever to fly to the L2 point from lunar ***,a transfer trajectory for the mission is designed based on InterPlanetary Superhighway theory under the constraint of the remaining propellant,TT&C (telemetry,track and command) and sunlight *** effects of trajectory maneuver errors on the mission are also ***,based on the analysis results,the article investigates the trajectory maneuver schemes for the lunar escape and transfer trajectory maneuvers employing mathematical models and operational *** mission status based on our maneuver schemes is then presented,and the results of control operation and corresponding analysis are provided in ***,the future trajectory maneuver in the Lissajous orbit is *** to the analysis of the CHANG'E-2 TT&C data,the trajectory maneuver schemes proposed in the article work properly and efficiently.

关键词： CHANG’E-2 libration point trajectory maneuver escape trajectory transfer trajectory

Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3 plus nicotine in rats

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Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3 Bin GENG~3 Jing ZHAO~3 Fang YU~3 Yong-zheng PANG~3 Chao-shu TANG~4 Yong-fen QI~(3,4,5) ~2Institute of Cardiovascular Disease,Peking University First Hospital.Beijing 100034 ~3Department of Physiology and Pathophysiology,Peking University Health Science Center,Beijing 100083,China,~4Key Laboratory of Molecular Cardiovascular Science,Ministry of Education,Beijing 100083,China 2Institute of Cardiovascular Disease Peking University First Hospital Beijing 100034 China 3Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China 4Key Laboratory of Molecular Cardiovascular Science Ministry of Education Beijing 100083 China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3 plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,45Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,45Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.42-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P34.8%,40.75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P3.9%,37.8 % and 46.2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

Distinct actions of intermittent and sustained β-adrenoceptor stimulation on cardiac remodeling

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Science China(Life Sciences) 2011年第6期54卷 493-501页

作者： MA XiaoWei1,3,SONG Yao1,3,CHEN Chao1,3,FU YongNan1,3,SHEN Qiang2,3,LI ZiJian1,3 & ZHANG YouYi1,3 1Institute of Vascular Medicine,Peking University Third Hospital,Beijing 100191,China 2Institute of Cardiovascular Science,Peking University,Beijing 100191,China 3Key Laboratory of Molecular Cardiovascular Sciences,Ministry of Education,Beijing 100191,China 1. Institute of Vascular Medicine Peking University Third Hospital Beijing 100191 China3. Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China2. Institute of Cardiovascular Science Peking University Beijing 100191 China

Heart disease is associated with increased sympathetic nerve activity and elevated levels of circulating catecholamines,resulting in chronic stimulation of the β-adrenergic receptors (β-AR) and consequent pathological cardiac ***,chronic administration of the β-AR agonist isoproterenol (ISO) has been most commonly used to model β-AR-induced cardiac ***,it remains unclear whether β-AR-mediated cardiac remodeling and dysfunction differs between sustained versus pulsatile (intermittent) exposure to a β-***,we compare the effects of intermittent versus sustained administration of ISO on cardiac remodeling and function in *** were administered 5 mg (kg d)-1 ISO for 2 weeks either by daily subcutaneous injection,or continuous infusion via an implanted osmotic *** function and remodeling were determined by echocardiography,micromanometry and ***,Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were utilized to define the proteins and genes *** sustained and intermittent administration of ISO resulted in a similar degree of cardiac hypertrophy (16% and 19%,respectively).However,mice receiving ISO by daily injection developed more severe ventricular systolic and diastolic dysfunction and myocardial fibrosis compared with mice receiving ISO via the osmotic *** disparity in results between the delivery methods is suggested to be due,at least in part,to increased expression of fibrogenic factors,including connective tissue growth factor (CTGF) and NADPH oxidase (NOX4),in mice receiving intermittent application of *** summary,compared with sustained exposure to a β-AR agonist,intermittent β-AR stimulation leads to more severe cardiac dysfunction and *** findings not only further our understanding of β-AR function in the setting of cardiac pathophysiology,but also highlight that significant differences can result dependent upon the mod

关键词： β-adrenoceptor reactive oxygen species NADPH oxidase cardiac hypertrophy cardiac fibrosis