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Chinese Medical Sciences Journal 2012年第1期27卷 41-45页

作者： jing-hua zhang Department of Dentistry Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Objective To assess whether Community Periodontal Index (CPI) teeth and random half-mouth methods are representative of full-mouth method in gingival bleeding examination. Methods Data from 1000 untreated adults (age > 18) collected in Beijing from January 2000 to January 2001 were utilized in the analysis. Half of the subjects were examined by Gingival Bleeding Index (GBI) and the other half by Sulcus Bleeding Index (SBI). The data were sorted out and calculated according to CPI teeth and random half-mouth teeth methods. The results of the 2 methods were separately compared with those of full-mouth examination. Results There was a significant difference between CPI teeth method and full-mouth examination (P0.05), nor in diagonal half-mouth results in GBI (P>0.05) Conclusions The results of CPI teeth method on gingival bleeding could not reflect the full-mouth situation. Ipsilateral and diagonal half-mouth results can serve as a substitute for full-mouth results in SBI, while diagonal half-mouth results in GBI.

关键词： Community Periodontal Index half-mouth examination full-mouth examina-tion Gingival Bleeding Index Sulcus Bleeding Index epidemiology

Synthesis and Biological Activity of Novel Spin Labeled Derivatives of 4′-Demethyl-4-deoxypodophyllotoxin

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Chemical Research in Chinese Universities 2010年第5期26卷 753-756页

作者： XU jing SUN Xiao-hua zhang Jia-qiang zhang Zhi-wei TIAN Xuan State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

Seven novel spin labeled derivatives of 4＇-demethyl-4-deoxypodophyllotoxin with nitroxyl radi- cals（TMHPO and TMPRO） were prepared and their cytotoxic and antioxidative activities were tested. Their cytotoxic activities were tested against two tumor cell lines（A-549 and HL-60） in vitro. Among them, five compounds show higher inhibition activity against A-549 cells compared with the clinical drug VP-16（2） and parent compound 4＇-demethyl-4-deoxypodophyllotoxin（DDPT, 6）. Compounds 8, 10 and 13 show excellent inhibition activity against HL-60 cells. Furthermore, the antioxidative activities of them were tested. All the seven spin labeled compounds show stronger antioxidative activity compared with VP-16（2） and DDPT（6）. The partition coefficients P of these derivatives were determined.

关键词： 4'-Demethyl-4-deoxypodophyllotoxin Nitroxyl radical Antiturnor activity Antioxidative activity

Dynamic Microwave-assisted Extraction of Flavonoids from Radix Scutellariae

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Chemical Research in Chinese Universities 2007年第2期23卷 148-153页

作者： YOU jing-yan zhang hua-rong DING Lan XIAO Ting-ting zhang Han-qi SONG Da-qian College of Chemistry Jilin University Changchun 130012 P. R. China

Dynamic microwave-assisted extraction（DMAE） of flavonoids from Radix Scutellarie was described in this article. A TM010 microwave resonant cavity was used as the energy coupler. Several parameters of DMAE, including concentration, flow rate, volume of the extraction solvent, and irradiation power, were optimized. The extraction was performed under the optimum conditions for the extraction of total flavonoids. The total flavonoids were determined by UV-Vis spectrophotometry. The main bioactive components, including baicalin, baicalein, and wogonin, were determined by HPLC. The extraction yields of the tlavonoids obtained by DMAE were compared with those obtained by pressurized microwave assisted extraction （ PMAE）, ultrasonic extraction （ UE ）, soxhlet extraction （ SE ）, and reflux extraction（ RE）, and these results indicate that DMAE is a good alternative method for the extraction of flavonoids from Radix Scutellade.

关键词： DMAE Flavonoids UV-Vis spectrophotometry HPLC

Selective separation and enrichment of proteins in aqueous two-phase extraction system

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Chinese Chemical Letters 2009年第9期20卷 1100-1102页

作者： Feng Qu Hao Qin Min Dong Dong Xu Zhao Xin Ying Zhao jing hua zhang School of Life Science Beijing Institute of Technology Beijing 100081 China Beijing Center for Physical and Chemical Analysis Beijing 100089 China

A simple aqueous two-phase extraction system （ATPS） of PEG/phosphate was proposed for selective separation and enrichment of proteins. The combination of ATPE with HPLC was applied to identify the partition of proteins in two phases. Five proteins （bovine serum albumin, Cytochrome C, lysozyme, myoglobin, and trypsin） were used as model proteins to study the effect of phosphate concentration and pH on proteins partition. The PEG/phosphate system was firstly applied to real human saliva and plasma samples, some proteins showed obviously different partition in two phases. The primary results manifest the selective separation and enrichment of proteins in ATPS provided the potential for high abundance proteins depletion in proteomics. ~ 2009 Feng Qu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Aqueous two-phase extraction Saliva and plasma Proteins Selective separation and enrichment

Variations of helioseismic parameters due to magnetic field generated by a flux transport model

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Research in Astronomy and Astrophysics 2021年第4期21卷 235-242页

作者： Shao-Lan Bi Tan-Da Li Kang Liu Jie Jiang Ya-Guang Li jing-hua zhang Xian-Fei zhang Ya-Qian Wu Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Physics and Astronomy University of BirminghamEdgbastonBirminghamB152TTUK School of Space and Environment Beihang UniversityBeijing 100871China Sydney Institute for Astronomy(SIfA) School of PhysicsUniversity of SydneyNSW 2006Australia Stellar Astrophysics Centre Department of Physics and AstronomyAarhus UniversityNy Munkegade 120DK-8000 Aarhus CDenmark National Astronomical Observatories Chinese Academy of SciencesBeijing

The change of sound speed has been found at the base of the convection during the solar cycles,which can be used to constrain the solar internal magnetic *** aim to check whether the magnetic field generated by the solar dynamo can lead to the cyclic variation of the sound speed detected through *** basic configuration of magnetic field in the solar interior was obtained by using a Babcock-Leighton(BL)type flux transport *** reconstructed one-dimensional solar models by assimilating magnetic field generated by an established dynamo and examined their influences on the structural *** results show that magnetic field generated by the dynamo is able to cause noticeable change of the sound speed profile at the base of the convective zone during a solar *** features of this theoretical prediction are also similar to those of the helioseismic results in solar cycle 23 by adjusting the free parameters of the dynamo model.

关键词： Sun:oscillations Sun:activity Sun:interior

Triple-transforming gel prepared byβ-cyclodextrin,diphenylamine and lithium chloride in N,N-dimethylacetamide

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Chinese Chemical Letters 2010年第10期21卷 1251-1254页

作者： Yuan Yuan Li Wen jing Zhao hua Cheng zhang Tao Sun Wei An Fei Fei Xin Ai You Hao School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China

This paper describes a triple-transforming gel system （gel-sol-gel＇） for the first time, which is a thermo-responsive and multi- component organogel prepared by β-cyclodextrin （β-CD）, diphenylamine （DPA） and lithium chloride （LiCl） in N,N-dimethyla- cetamide （DMAC） in a suitable proportion based on the supramolecular interactions. In the triple-transfomaing gel system, a gel （gel A） could be formed by β-CD, DPA and LiCl in DMAC at room temperature based on stirring, then the gel could transform into a clear solution based on heating, and then the other gel （gel B） can be formed at a relatively high temperature （Tget, the gelation temperature by heating）. The two gel states in the triple-transforming gel system have different microstructures. This gel system was characterized by OM, SEM, IR and theology.

关键词： Gel Triple-transforming β-Cyclodextrin Lithium N,N-Dimethylacetamide

Dual antiplatelet therapy increases pocket hematoma complications in Chinese patients with pacemaker implantation

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Journal of Geriatric Cardiology 2015年第4期12卷 383-387页

作者： Yan DAI Ke-Ping CHEN Wei hua jing-Tao zhang Shu zhang State Key Laboratory of Cardiovascular Disease Arrhythmia Center Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China

Objective To assess the prevalence of the bleeding complications in pacemaker implanted patients receiving different antiplatelet regimens, and the influence of each regimen on hospital stays after device implantation. Methods We prospectively enrolled 364 patients receiving the cardiac rhythm device implantations in Fuwai Hospital from July 2012 to December 2013. Bleeding complications including pocket hematoma, hemothorax, cardiac tamponade and blood transfusion requirement were measured as endpoints. Post operation hospital stay was also included in the endpoints. Results Bleeding complications were detected in 15 patients （14 with hematoma, one with hemothorax） out of all 364 patients （4.12%）. Dual antiplatelet therapy （DAT） significantly increased hematoma （19.3%） compared with aspi- fin treatment （ASA）（3.2%, P = 0.001） and no antiplatelet therapy （1.9%, P 〈 0.001）. There was no significant difference in incidence of pocket hematoma between the ASA group and the control group （P = 0.45）. The post procedure hospital stay was longer in DAT group （5.45 ± 2.01 days） compared to those in the ASA group （3.65 ± 1.37 days, P 〈 0.05） or control group （3.99 ± 2.27 days, P 〈 0.05）. Pocket hema- toma was considered an independent predictor of hospital stay prolongation （OR： 5.26; 95% CI： 1.56-16.64; P = 0.007）. Conclusions Among the Chinese patients undergoing device implantation in this study, the use of dual antiplatelet agents significantly increased the risk of pocket hematoma complications and led to a longer hospital stay. Use of aspirin alone did not increase the risk.

关键词： Complication Dual antiplatelet therapy Hematoma Pacemaker

Free vibration of functionally graded beams based on both classical and first-order shear deformation beam theories

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Applied Mathematics and Mechanics(English Edition) 2014年第5期35卷 591-606页

作者：李世荣万泽青张静华 School of Civil Science and Engineering Yangzhou University

The free vibration of functionally graded material （FGM） beams is studied based on both the classical and the first-order shear deformation beam theories. The equations of motion for the FGM beams are derived by considering the shear deforma- tion and the axial, transversal, rotational, and axial-rotational coupling inertia forces on the assumption that the material properties vary arbitrarily in the thickness direction. By using the numerical shooting method to solve the eigenvalue problem of the coupled ordinary differential equations with different boundary conditions, the natural frequen- cies of the FGM Timoshenko beams are obtained numerically. In a special case of the classical beam theory, a proportional transformation between the natural frequencies of the FGM and the reference homogenous beams is obtained by using the mathematical similarity between the mathematical formulations. This formula provides a simple and useful approach to evaluate the natural frequencies of the FGM beams without dealing with the tension-bending coupling problem. Approximately, this analogous transition can also be extended to predict the frequencies of the FGM Timoshenko beams. The numerical results obtained by the shooting method and those obtained by the analogous transformation are presented to show the effects of the material gradient, the slenderness ratio, and the boundary conditions on the natural frequencies in detail.

关键词： functionally graded material (FGM) Timoshenko beam free vibration,shooting method analogous transformation

Binary Star Fractions from the LAMOST DR4

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Research in Astronomy and Astrophysics 2018年第5期18卷 47-58页

作者： Zhi-Jia Tian Xiao-Wei Liu Hai-Bo Yuan Bing-Qiu Chen Mao-Sheng Xiang Yang huang Chun Wang hua-Wei zhang Jin-Cheng Guo Juan-Juan Ren Zhi-Ying Huo Yong Yang Meng zhang Shao-Lan Bi Wu-Ming Yang Kang Liu Xian-Fei zhang Tan-Da Li Ya-Qian Wu jing-hua zhang Department of Astronomy Peking University Beijing 100871 China Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China Department of Astronomy Yunnan University Kunming 650091 China

Stellar systems composed of single, double, triple or higher-order systems are rightfully regarded as the fundamental building blocks of the Milky Way. Binary stars play an important role in formation and evolution of the Galaxy. Through comparing the radial velocity variations from multiepoch observations, we analyze the binary fraction of dwarf stars observed with LAMOST. Effects of different model assumptions, such as orbital period distributions on the estimate of binary fractions,are investigated. The results based on log-normal distribution of orbital periods reproduce the previous complete analyses better than the power-law distribution. We find that the binary fraction increases with Teff and decreases with [Fe/H]. We first investigate the relation between α-elements and binary fraction in such a large sample as provided by LAMOST. The old stars with high [α/Fe] dominate with a higher binary fraction than young stars with low [α/Fe]. At the same mass, earlier forming stars possess a higher binary fraction than newly forming ones, which may be related with evolution of the Galaxy.

关键词： binaries general- binaries spectroscopic - Galaxy stellar content - stars statistics- surveys

Stellar parameters of main sequence turn-off star candidates observed with LAMOST and Kepler

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Research in Astronomy and Astrophysics 2017年第1期17卷 55-70页

作者： Ya-Qian Wu Mao-Sheng Xiang Xian-Fei zhang Tan-Da Li Shao-Lan Bi Xiao-Wei Liu Jian-Ning Fu Yang huang Zhi-Jia Tian Kang Liu Zhi-Shuai Ge Xin He jing-hua zhang Department of Astronomy Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University

Main sequence turn-off （MSTO） stars since their ages can be robustly estimated from have advantages as indicators of Galactic evolution atmospheric parameters. Hundreds of thousands of MSTO stars have been selected from the LAMOST Galactic survey to study the evolution of the Galaxy, and it is vital to derive accurate stellar parameters. In this work, we select 150 MSTO star candidates from the MSTO star sample of Xiang that have asteroseismic parameters and determine accurate stellar parameters for these stars by combining asteroseismic parameters deduced from Kepler photometry and atmospheric parameters deduced from LAMOST spectra. With this sample, we examine the age determination as well as the contamination rate of the MSTO star sample. A comparison of age between this work and Xiang shows a mean difference of 0.53 Gyr （7%） and a dispersion of 2.71 Gyr （28%）. The results show that 79 of the candidates are MSTO stars, while the others are contaminations from either main sequence or sub-giant stars. The contamination rate for the oldest stars is much higher than that for younger stars. The main cause for the high contamination rate is found to be the relatively large systematic bias in the LAMOST surface gravity estimates.

关键词： stars: fundamental parameters - stars evolution - stars asteroseismology