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Oxidative stress and peripheral skeletal muscle dysfunction in rats with emphysema

Chinese Medical Journal 2010年第1期123卷 40-44页

作者： ZHANG xiao-lei PANG Bao-sen hou xiao-li WANG Jun WANG Chen Department of Respiratory Medicine Beijing Institute ofRespiratory Medicine Beijing Chaoyang Hospital Capital MedicalUniversity Beijing 100020 China Department of Physiology Capital Medical University Beijing100069 China

Background Peripheral skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease （COPD） may be due to the disease per se or as a result of concomitant confounding factors. Although the mechanistic basis for this functional impairment is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether local oxidative stress is associated with the reduced peripheral skeletal muscle performance in rats with emphysema. Methods In situ mechanical properties of gastrocnemius were measured in Sprague-Dawley rats 5 months after intratracheal instillation of either elastase （EMP, n=-10） or normal saline （CON, n=10）. lipofuscin inclusions, myocyte apoptosis and antioxidant enzyme activities were examined in the gastrocnemius muscle. Results lipofuscin inclusions were significantly higher in the gastrocnemius muscle of EMP compared with CON （3.2_--,-0.4 vs. 1.7_＋0.4, P〈0.01 ）. The activities of antioxidant enzymes were significantly increased in muscle homogenates of EMP as compared to CON. No significant differences were found in myocyte apoptosis between EMP and CON （1.2±0.9 vs. 1.0±0.8, P 〉0.05）. EMP decreased the fatigue endurance of gastrocnemius muscle （half-time to fatigue recovery：（150.0±55.4） seconds vs. （55.2±29.3） seconds, P 〈0.01） and had no effect on maximal tetanic force （（467.4±36.6） g vs. （493.2±30.5） g, P 〉0.05）. A significantly positive correlation was found between the level of lipofuscin inclusions and the half-time to fatigue recovery of gastrocnemius muscle in EMP （r=0.664, P 〈0.05）. Conclusion Local oxidative stress may have important functional consequences for peripheral skeletal muscle in rats with EMP.

关键词： emphysema peripheral skeletal muscle dysfunction oxidative stress

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安徽省公共资源交易开评标现场管理标准化研究与应用

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中国标准化 2024年第3期 102-105页

作者：侯晓丽张靖舒方玲吴倩安徽合肥公共资源交易中心安徽省质量和标准化研究院

开标、评标环节是公共资源交易活动的核心,也是体现公共资源交易效率和公平性的重要内容,一直备受社会关注。本文在深入分析安徽省公共资源交易标准化服务现状的基础上,探讨了公共资源交易开评标现场管理过程中,运用标准化的形式对实践... 详细信息

开标、评标环节是公共资源交易活动的核心,也是体现公共资源交易效率和公平性的重要内容,一直备受社会关注。本文在深入分析安徽省公共资源交易标准化服务现状的基础上,探讨了公共资源交易开评标现场管理过程中,运用标准化的形式对实践工作的先进经验进行提炼固化的问题。提出对开评标现场管理的规范化、标准化建设的基本要求,明确现场管理内容,促进公共资源交易现场管理的标准化水平提升,为公共资源交易服务提质增效起到重要支撑作用。

关键词：公共资源交易开评标现场管理标准化

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HPLC法测定广西不同产地八角茴香中4种有机酸的含量

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广西中医药大学学报 2024年第1期27卷 53-57页

作者：欧敏潘宇陈路赵成坚侯小利谭栀恩张孟丽李晓玲吴芳芳广西壮族自治区药用植物园广西南宁530023 西南濒危药材资源开发国家工程实验室广西南宁530023 右江民族医学院广西百色533000

[目的]建立八角茴香中莽草酸、原儿茶酸、对羟基苯甲酸、对甲氧基苯甲酸的含量测定方法。[方法]采用高效液相色谱法对八角茴香进行测定,色谱柱为Kromasil 100-5-C_(18)(250 mm×4.6 mm,5μm),流动相为乙腈-3%磷酸水溶液(梯度洗脱),流速... 详细信息

[目的]建立八角茴香中莽草酸、原儿茶酸、对羟基苯甲酸、对甲氧基苯甲酸的含量测定方法。[方法]采用高效液相色谱法对八角茴香进行测定,色谱柱为Kromasil 100-5-C_(18)(250 mm×4.6 mm,5μm),流动相为乙腈-3%磷酸水溶液(梯度洗脱),流速为1.0 ml/min,进样量为10μl,检测波长为254 nm,柱温为40℃。[结果]广西11个不同产地的八角茴香中莽草酸含量为6.34%~7.41%,原儿茶酸含量为0.28%~0.98%,对羟基苯甲酸含量为0.73%~1.90%,对甲氧基苯甲酸含量为0.07%~0.23%。[结论]本研究建立的方法操作简单,稳定性强,重复性好,可用于八角茴香中有效成分的含量测定。

关键词：八角茴香莽草酸原儿茶酸对羟基苯甲酸对甲氧基苯甲酸高效液相色谱法含量测定

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Comprehensive understanding of glioblastoma molecular phenotypes:classification,characteristics,and transition

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Cancer Biology & Medicine 2024年第5期21卷 363-381页

作者： Can Xu Pengyu hou Xiang li Menglin xiao Ziqi Zhang Ziru li Jianglong Xu Guoming liu Yanli Tan Chuan Fang School of Clinical Medicine Hebei UniversityDepartment of NeurosurgeryAffiliated Hospital of Hebei UniversityBaoding 07100China Hebei Key Laboratory of Precise Diagnosis and Treatment of Glioma Baoding 071000China School of Basic Medical Sciences Hebei UniversityBaoding 07100China Department of Pathology Affiliated Hospital of Hebei UniversityBaoding 07100China

Among central nervous system-associated malignancies,glioblastoma(GBM)is the most common and has the highest mortality rate.The high heterogeneity of GBM cell types and the complex tumor microenvironment frequently lead to tumor recurrence and sudden relapse in patients treated with temozolomide.In precision medicine,research on GBM treatment is increasingly focusing on molecular subtyping to precisely characterize the cellular and molecular heterogeneity,as well as the refractory nature of GBM toward therapy.Deep understanding of the different molecular expression patterns of GBM subtypes is critical.Researchers have recently proposed tetra fractional or tripartite methods for detecting GBM molecular subtypes.The various molecular subtypes of GBM show significant differences in gene expression patterns and biological behaviors.These subtypes also exhibit high plasticity in their regulatory pathways,oncogene expression,tumor microenvironment alterations,and differential responses to standard therapy.Herein,we summarize the current molecular typing scheme of GBM and the major molecular/genetic characteristics of each subtype.Furthermore,we review the mesenchymal transition mechanisms of GBM under various regulators.

关键词： Glioblastoma molecular phenotype classification characteristic mesenchymal transition

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Novel insights into immune-related genes associated with type 2 diabetes mellitus-related cognitive impairment

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World Journal of Diabetes 2024年第4期15卷 735-757页

作者： Jing Gao Ying Zou xiao-Yu Lv li Chen Xin-Guo hou Department of Endocrinology Qilu Hospital of Shandong UniversityCheeloo College of MedicineShandong UniversityJinan 250012Shandong ProvinceChina Institute of Endocrine and Metabolic Diseases Shandong UniversityJinan 250012Shandong ProvinceChina Key Laboratory of Endocrine and Metabolic Diseases Shandong Province Medicine&HealthJinan 250012Shandong ProvinceChina Department of Endocrinology Jinan Clinical Research Center for Endocrine and Metabolic DiseaseJinan 250012Shandong ProvinceChina

BACKGROUND The cognitive impairment in type 2 diabetes mellitus(T2DM)is a multifaceted and advancing state that requires further exploration to fully comprehend.Neu-roinflammation is considered to be one of the main mechanisms and the immune system has played a vital role in the progression of the disease.AIM To identify and validate the immune-related genes in the hippocampus associated with T2DM-related cognitive impairment.METHODS To identify differentially expressed genes(DEGs)between T2DM and controls,we used data from the Gene Expression Omnibus database GSE125387.To identify T2DM module genes,we used Weighted Gene Co-Expression Network Analysis.All the genes were subject to Gene Set Enrichment Analysis.Protein-protein interaction network construction and machine learning were utilized to identify three hub genes.Immune cell infiltration analysis was performed.The three hub genes were validated in GSE152539 via receiver operating characteristic curve analysis.Validation experiments including reverse transcription quantitative real-time PCR,Western blotting and immunohistochemistry were conducted both in vivo and in vitro.To identify potential drugs associated with hub genes,we used the Comparative Toxicogenomics Database(CTD).RESULTS A total of 576 DEGs were identified using GSE125387.By taking the intersection of DEGs,T2DM module genes,and immune-related genes,a total of 59 genes associated with the immune system were identified.Afterward,machine learning was utilized to identify three hub genes(H2-T24,Rac3,and Tfrc).The hub genes were associated with a variety of immune cells.The three hub genes were validated in GSE152539.Validation experiments were conducted at the mRNA and protein levels both in vivo and in vitro,consistent with the bioinformatics analysis.Additionally,11 potential drugs associated with RAC3 and TFRC were identified based on the CTD.CONCLUSION Immune-related genes that differ in expression in the hippocampus are closely linked to microglia.We validated the expression of three hub genes

关键词： Bioinformatics analysis Type 2 diabetes mellitus Cognitive impairment Hippocampus Immune Microglia

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Investigation of high rate mechanical flow followed by ignition for high-energy propellant under dynamic extrusion loading

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Defence Technology（防务技术） 2024年第2期32卷 336-347页

作者： liying Dong Yanqing Wu Kun Yang xiao hou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Investigating the ignition response of nitrate ester plasticized polyether(NEPE) propellant under dynamic extrusion loading is of great significant at least for two cases. Firstly, it helps to understand the mechanism and conditions of unwanted ignition inside charged propellant under accident stimulus.Secondly, evaluates the risk of a shell crevice in a solid rocket motor(SRM) under a falling or overturning scene. In the present study, an innovative visual crevice extrusion experiment is designed using a dropweight apparatus. The dynamic responses of NEPE propellant during extrusion loading, including compaction and compression, rapid shear flow into the crevice, stress concentration, and ignition reaction, have been firstly observed using a high-performance high-speed camera. The ignition reaction is observed in the triangular region of the NEPE propellant sample above the crevice when the drop weight velocity was 1.90 m/s. Based on the user material subroutine interface UMAT provided by finite element software LS-DYNA, a viscoelastic-plastic model and dual ignition criterion related to plastic shear dissipation are developed and applied to the local ignition response analysis under crevice extrusion conditions. The stress concentration occurs in the crevice location of the propellant sample, the shear stress is relatively large, the effective plastic work is relatively large, and the ignition reaction is easy to occur. When the sample thickness decreases from 5 mm to 2.5 mm, the shear stress increases from 22.3 MPa to 28.6 MPa, the critical value of effective plastic work required for ignition is shortened from 1280 μs to 730 μs, and the triangular area is easily triggering an ignition reaction. The propellant sample with a small thickness is more likely to stress concentration, resulting in large shear stress and effective work, triggering an ignition reaction.

关键词： NEPE propellant Crevice extrusion Shear flow Sample thickness Ignition reaction

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Effects of arsenic on seed germination and physiological activities of wheat seedlings

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Journal of Environmental Sciences 2007年第6期19卷 725-732页

作者： li Chun-xi FENG Shu-li SHAO Yun JIANG li-na LU Xu-yang hou xiao-li College of life Sciences Henan Normal University Xinxiang 453007 China

The effects of arsenic （As） were investigated on seed germination, root and shoot length and their biomass and some other factors to elucidate the toxicity of As. The results showed low concentrations of As （0-1 mg/kg） stimulated seed germination and the growth of root and shoot, however, these factors all decreased gradually at high concentrations of As （5-20 mg/kg）. The contents of O2^-, MDA, soluble protein and peroxidase （POD） activity all increased with increasing As concentrations. Soluble sugar content, ascorbate peroxidase （APX）, and superoxide dismutase （SOD） activities decreased at low concentrations of As, and increased at high concentrations of As. While acetylsalicylic acid （ASA） and chlorophyll contents, catalase （CAT） activity displayed increasing trend when the concentrations of As was lower than 1 mg/kg, and then decreasing trend. By polyacrylamide gel electrophoresis （PAGE）, As induced the expression of POD isozymes of wheat seedlings. As induced the expression of CAT isozymes but inhibited the expression of SOD isozymes of wheat seedlings at concentrations lower than 1 mg/kg. However, As inhibited the expression of CAT isozymes but induced the expression of SOD isozymes at concentrations higher than 5 mg/kg. The results indicated As could exert harmfulness in the early development stage of wheat at inappropriate concentrations.

关键词： arsenic wheat germination physiological activities

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A Transient-Pressure-Based Numerical Approach for Interlayer Identification in Sand Reservoirs

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Fluid Dynamics & Materials Processing 2024年第3期20卷 641-659页

作者： Hao Luo Haibo Deng Honglin xiao Shaoyang Geng Fu hou Gang Luo Yaqi li Tight Oil and Gas Exploration and Development Project Department PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Energy College Chengdu University of TechnologyChengdu610059China

Almost all sandstone reservoirs contain interlayers. The identification and characterization of these interlayers iscritical for minimizing the uncertainty associated with oilfield development and improving oil and gas recovery.Identifying interlayers outside wells using identification methods based on logging data and machine learning isdifficult and seismic-based identification techniques are expensive. Herein, a numerical model based on seepageand well-testing theories is introduced to identify interlayers using transient pressure data. The proposed modelrelies on the open-source MATLAB Reservoir Simulation Toolbox. The effects of the interlayer thickness, position,and width on the pressure response are thoroughly investigated. A procedure for inverting interlayer parametersin the reservoir using the bottom-hole pressure is also proposed. This method uses only transient pressuredata during well testing and can effectively identify the interlayer distribution near the wellbore at an extremelylow cost. The reliability of the model is verified using effective oilfield examples.

关键词： Sand reservoir interlayer identification transient pressure analysis numerical well test

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Stark splitting of intense red emission for Er^(3+)in O_(h) symmetry sites realizing optical temperature sensing in biological applications

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Rare Metals 2024年第3期43卷 1263-1274页

作者： Yue Guo lin-Jun Qin Jing Xu xiao-Ping Jiang xiao-Yu Yue Yi hou Hao Shi li-Xi Wang Qi-Tu Zhang Collage of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing211816China

Optical temperature sensing based on the fluorescence intensity ratio(FIR)of red emission for lanthanide ions holds significant relevance in non-contact temperature measurement for biological application.In this study,the perovskite-structured KZnF_(3)is utilized as a host material for Er^(3+)to achieve a high-purity upconversion(UC)red emission.The observed Stark splitting of the red emission peak provides evidence of the energy level splitting of Er^(3+).Group theory is employed to decompose the spectral branching of Er^(3+)under the point group symmetry of KZnF_(3),allowing for the derivation of Stark splitting energy levels induced by the crystal field effect.The optical temperature-sensing behavior of the red UC luminescence was investigated,specifically examining the FIR of the splitting sub-peaks,which exhibited an exponential relationship with temperature.The KZnF_(3):Yb^(3+),Er^(3+)demonstrated a relative sensitivity(S_(r))of 0.00182%·K^(-1)at 298 K,highlighting its excellent response to temperature.Ex vivo bio-thermometry experiments conducted on chicken breast validated the material's ability to penetrate biological tissues and showed its significant sensitivity of the FIR to temperature.These results establish KZnF_(3):Yb^(3+),Er^(3+)as a promising material for optical thermometry in various biological applications.

关键词： KZnF_(3) Er^(3+) Upconversion luminescence Stark splitting Temperature sensing

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An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-Time Switched LQR Problem

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Journal of Systems Science & Complexity 2024年第1期37卷 22-39页

作者： hou Tan li Yuanlong liN Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR problem.In particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value function.This method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing methods.Three numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

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