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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

Association of prealbumin with short-term and long-term outcomes in patients with acute ST-segment elevation myocardial infarction

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Journal of Geriatric Cardiology 2024年第4期21卷 421-430页

作者： jing TAN Jin SI Ke-Ling XIAO Ying-hua zhang Qi hua jing LI Department of Cardiology Xuanwu Hospital Capital Medical UniversityBeijingChina Department of Geriatric Medicine Xuanwu Hospital Capital Medical UniversityNational Clinical Research Center for Geriatric DiseasesBeijingChina

BACKGROUND Prealbumin is considered to be a useful indicator of nutritional status. Furthermore, it has been found to be associated with severities and prognosis of a range of diseases. However, limited data on the association of baseline prealbumin level with outcomes of patients with acute ST-segment elevation myocardial infarction(STEMI) are *** We analyzed 2313 patients admitted for acute STEMI between October 2013 and December 2020. In-hospital outcomes and mortality during the 49 months(interquartile range: 26–73 months) follow-up period were compared between patients with the low prealbumin level(< 170 mg/L) and those with the high prealbumin level(≥ 170 mg/L).RESULTS A total of 114 patients(4.9%) died during hospitalization. After propensity score matching, patients with the low prealbumin level than those with the high prealbumin level experienced higher incidences of heart failure with Killip class Ⅲ(9.9%vs. 4.4%, P = 0.034), cardiovascular death(8.4% vs. 3.4%, P = 0.035) and the composite of major adverse cardiovascular events(19.2%vs. 10.3%, P = 0.012). Multivariate logistic regression analysis identified that the low prealbumin level(< 170 mg/L) was an independent predictor of in-hospital major adverse cardiovascular events(odds ratio = 1.918, 95% CI: 1.250–2.942, P = 0.003). The cutoff value of prealbumin level for predicting in-hospital death was 170 mg/L(area under the curve = 0.703, 95% CI: 0.651–0.754, P< 0.001;sensitivity = 0.544, specificity = 0.794). However, after multivariate adjustment of possible confounders, baseline prealbumin level(170 mg/L) was no longer independently associated with 49-month cardiovascular death. After propensity score matching, Kaplan-Meier survival curves revealed consistent *** Decreased prealbumin level closely related to unfavorable short-term outcomes. However, after multivariate adjustment and controlling for baseline differences, baseline prealbumin level was not independently assoc

关键词： patients admitted infarction

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

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin Sheng-Da Zhao Zhi-Xin Liu jing zhang Xing-hua zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

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

Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality

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Petroleum Science 2024年第3期21卷 2139-2153页

作者： Zhen-hua zhang Dan Ling Qin-Xin Yang Yan-Chao Feng jing Xiu School of Economics Lanzhou UniversityLanzhou 730000GansuChina Institute of Green Finance Lanzhou UniversityLanzhou 730000GansuChina School of Management Lanzhou UniversityLanzhou 730000GansuChina School of Business Zhengzhou UniversityZhengzhou 450001HenanChina Institute of Economics Jilin Academy of Social SciencesChangchun130033JilinChina

Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction *** study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each *** research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI *** the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary ***,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy *** study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy.

关键词： Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction

Corrosion Behavior of Graphene Nanosheets Reinforced Magnesium Matrix Composites in Simulated Body Fluids

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 525-536页

作者： Liwen Chen Jianhui jing Lulu zhang jing Li Weipeng Chen Limin Li Yuan Zhao hua Hou Yuhong Zhao School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Shanxi Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringNorth University of ChinaTaiyuan 030051China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Magnesium(Mg)alloy is considered as a promising biodegradable implant material but restricted to rapid ***,the new strategies based on thixomolding process had been explored to utilize the outstanding anti-permeability of graphene nanosheets(GNPs)while inhibit its galvanic corrosion with the matrix,so as to improve the corrosion resistance of *** agglomerate of GNPs with 0.9 wt%content is the main reason for the deterioration of corrosion performance due to the formation of micro-galvanic *** grain refinement of composites with 0.6 wt%content had positive effects on the better corrosion *** process adjusting,the unique distributions of GNPs along grain boundaries play a vital role in improving the corrosion *** can be ascribed to the following mechanisms:(I)The barriers can be established between the Mg matrix and corrosive medium,hence blocking the charge transfer at the interface;(II)The GNPs can effectively promote apatite deposition on the Mg matrix,leading to form dense apatite layers and prevent the further invasion of SBF;(III)The GNPs acting as reinforcements exists in the corrosion layer and apatite layer,impede the apatite layer falling off from the Mg *** findings broaden the horizon for biomedical applications in Mg matrix composites to realize desired performances.

关键词： Magnesium matrix composite Graphene nanosheets Corrosion resistance

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