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Evaluation and Analysis of Hospital Disaster Preparedness in Jeddah 被引量:1
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作者 Nidaa A. Bajow Shahnaz M. Alkhalil 《Health》 2014年第19期2668-2687,共20页
Introduction: Disaster damage to health systems is a human and health tragedy, results in huge economic losses, deals devastating blows to development goals, and shakes social confidence. Hospital disaster preparednes... Introduction: Disaster damage to health systems is a human and health tragedy, results in huge economic losses, deals devastating blows to development goals, and shakes social confidence. Hospital disaster preparedness presents complex clinical operation. It is difficult philosophical challenge. It is difficult to determine how much time, money, and effort should be spent in preparing for an event that may not occur. Health facilities whether hospitals or rural health clinics, should be a source of strength during emergencies and disasters. They should be ready to save lives and to continue providing essential emergencies and disasters. Jeddah has relatively a level of disaster risk which is attributable to its geographical location, climate variability, topography, etc. This study investigates the hospital disaster preparedness (HDP) in Jeddah. Methods: Questionnaire was designed according to five Likert scales. It was divided into eight fields of 33 indicators: structure, architectural and furnishings, lifeline facilities’ safety, hospital location, utilities maintenance, surge capacity, emergency and disaster plan, and control of communication and coordination. Sample of six hospitals participated in the study and rated to the extent of disaster preparedness for each hospital disaster preparedness indicators. Two hazard tools were used to find out the hazards for each hospital. An assessment tool was designed to monitor progress and effectiveness of the hospitals’ improvement. Weakness was found in HDP level in the surveyed hospitals. Disaster mitigation needs more action including: risk assessment, structural and non-structural prevention, and preparedness for contingency planning and warning and evacuation. Conclusion: The finding shows that hospitals included in this study have tools and indicators in hospital preparedness but with lack of training and management during disaster. So the research shed light on hospital disaster preparedness. Considering the importance of preparedness in disaster, it is necessary for hospitals to understand that most of hospital disaster preparedness is built in the hospital system. 展开更多
关键词 hOSPITAL DISASTER PREPAREDNESS Indicators (hDPI) hOSPITAL DISASTER PREPAREDNESS (hDP) hazard Vulnerability Analysis (hVA) Mass CASUALTY Incident (MCI) Full-Scale Exercises (FSE) Emergency Medical Services (EMS) Joint Commission on Accreditation of healthcare Organizations (JCAhO) Pan American health Organization (PAhO) hypothesis (h)
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A breakthrough approach to hydrogen peroxide synthesis:Defect-enhanced catalysis in SnSe nanosheets
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作者 Ziyan Wang Yihe Gao Chao Han 《Chinese Journal of Structural Chemistry》 2025年第10期1-2,共2页
Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its... Hydrogen peroxide(H_(2)O_(2)),as a green oxidant,plays a vital role in various applications,including environmental remediation,disinfection,and chemical synthesis[1].The conventional anthraquinone process,despite its industrial maturity and high yield,suffers from high energy consumption,carbon emissions,safety risks,and reliance on precious metals[2].Despite ongoing optimizations,a more sustainable alternative is urgently needed.The direct synthesis of hydrogen peroxide from water and oxygen has long been considered as an ideal alternative due to its theoretical 100%atom efficiency and environmental sustainability. 展开更多
关键词 SnSe nanosheets hydrogen peroxide h o hydrogen peroxide synthesis chemical synthesis anthraquinone processdespite environmental remediationdisinfectionand hydrogen peroxide direct synthesis
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Boosting interfacial charge-transfer kinetics via core-shell MOF heterostructures with shared metal nodes
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作者 Weilai Yu 《Chinese Journal of Catalysis》 2025年第6期8-11,共4页
Artificial photosynthesis presents a sustainable and cost-effective approach to harnessing solar energy to produce value-added chemicals[1,2].In particular,the simultaneous photocatalytic conversion of CO_(2)and H_(2)... Artificial photosynthesis presents a sustainable and cost-effective approach to harnessing solar energy to produce value-added chemicals[1,2].In particular,the simultaneous photocatalytic conversion of CO_(2)and H_(2)O into formic acid(HCOOH)and hydrogen peroxide(H2O2)has emerged as a promising strategy to mitigate global warming driven by CO_(2)emissions.HCOOH is a versatile chemical and hydrogen carrier,offering economic and practical advantages due to its compatibility with existing industrial processes and energy storage/conversion systems.Meanwhile,H_(2)O_(2)is among the world’s top 100 essential chemicals,with a global market valued at$4.0 billion in 2020 and projected to grow to$5.2 billion by 2026. 展开更多
关键词 interfacial charge transfer artificial photosynthesis mitigate global warming core shell formic acid hcooh photocatalytic conversion chemical hydrogen carrieroffering hydrogen peroxide h o
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Precision and trueness of a method for determing antimony content in groundwater using hydride generation-atomic fluorescence spectrometry
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作者 Bing-bing Liu Lin Zhang Ke Li 《Journal of Groundwater Science and Engineering》 2026年第1期49-58,共10页
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema... At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater. 展开更多
关键词 Mandel's h and k statistics Grubbs test Cochran test Repeatability limit Reproducibility limit Method bias value
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Many-Body Enhancement of Excitonic Electron–Hole Recombination in Two-Dimensional Transition Metal Dichalcogenides
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作者 Li Yao Xiang Jiang +1 位作者 Qijing Zheng Jin Zhao 《Chinese Physics Letters》 2026年第1期134-141,共8页
Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-... Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-mediated e–h recombination the dominant decay pathway.In this work,nonradiative e–h recombination within excitons in monolayer MoS2 is investigated using first-principles simulations that combine nonadiabatic molecular dynamics with𝐺𝑊and real-time Bethe–Salpeter equation(BSE)propagation.A two-step process is identified:rapid intervalley redistribution induced by exchange interaction,followed by slower phonon-assisted recombination facilitated by exciton binding.By selectively removing the screened Coulomb and exchange terms from the BSE Hamiltonian,their respective contributions are disentangled—exchange interaction is found to increase the number of accessible recombination pathways,while binding reduces the excitation energy and enhances nonradiative decay.A reduction in recombination lifetime by over an order of magnitude is observed due to the excitonic many-body effects.These findings provide microscopic insights for understanding and tuning exciton lifetimes in 2D transition-metal dichalcogenides. 展开更多
关键词 energy dissipation tightly bound excitons many body effects excitonic recombination nonadiabatic molecular dynamics e h recombination decay pathwayin monolayer mos
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考虑V2H的智能社区能量交易方案
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作者 刘迪迪 姚欣欣 +3 位作者 廖志贤 杨文宇 沈阳 胡聪 《华北电力大学学报(自然科学版)》 北大核心 2026年第1期71-81,105,I0005,I0006,共14页
针对含光伏(photovoltaic,PV)、电动汽车(electric vehicle,EV)及家庭电器负荷的智能社区,以车入户(vehicle to home,V2H)的形式将EV纳入家庭需求响应框架,利用EV的双向输能特性并考虑EV充/放电带来的电池容量退化成本,协同PV、电网的... 针对含光伏(photovoltaic,PV)、电动汽车(electric vehicle,EV)及家庭电器负荷的智能社区,以车入户(vehicle to home,V2H)的形式将EV纳入家庭需求响应框架,利用EV的双向输能特性并考虑EV充/放电带来的电池容量退化成本,协同PV、电网的实时电价和用户需求的可容忍时延,基于Lyapunov优化理论提出随机环境下V2H用户的EV充/放电调度策略和每户家庭的负荷响应策略,最小化家庭用户的长期平均购电成本。并提出一种智能社区在线能量交易方案,旨在最小化智能社区总的购电成本、最大限度提高社区能源利用率。理论分析和仿真结果表明,所提算法无需实时电价、PV出力、用户负荷需求的先验概率信息,仅基于当前系统状态就可使优化目标趋于最优值,实现家庭用户的能量调度和家庭用户之间的能量共享,减少家庭购电成本,提高用户之间能量交易的灵活性。 展开更多
关键词 智能社区 Lyapunov优化 电动汽车 V2h 能量共享
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温阳益气方通过GAS/CCKBR抑制肠道NHE3活性调节钠吸收治疗慢传输型便秘的作用机制
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作者 吴本升 何宗琦 +1 位作者 周青 王晓鹏 《辽宁中医杂志》 北大核心 2026年第1期168-173,I0004,I0005,共8页
目的研究温阳益气方(Wenyang Yiqi Formula,WYF)对胃泌素(gastrin,GAS)/胆囊收缩素B受体(cholecystokinin B receptor,CCKBR)及钠氢交换体3(Na^(+)/H^(+)exchanger3,NHE3)的影响,并探讨其治疗慢传输型便秘(slow transit constipation,S... 目的研究温阳益气方(Wenyang Yiqi Formula,WYF)对胃泌素(gastrin,GAS)/胆囊收缩素B受体(cholecystokinin B receptor,CCKBR)及钠氢交换体3(Na^(+)/H^(+)exchanger3,NHE3)的影响,并探讨其治疗慢传输型便秘(slow transit constipation,STC)的机制。方法采用STC大鼠和Caco-2细胞作为体内和体外模型。评估下列指标:肠道转运率(ITR)、结肠组织病理学、粪便特征,从而评价WYF的疗效。此外,检测细胞活力、NHE3活性及表达量和GAS/CCKBR水平。同时检测PI3K/PLC/PKC通路中的关键蛋白表达,并进行PI3K抑制剂实验。结果与正常对照组相比,STC大鼠ITR下降、粪便排出减少并呈干结,结肠组织病理损伤加重,WYF可缓解上述情况;体外实验显示,WYF含药血清可抑制Caco-2细胞NHE3活性及蛋白表达,呈剂量依赖性;高浓度在24-72 h可降低细胞活力。机制方面,GAS上调CCKBR并激活PI3K/PLC/PKC相关信号,同时抑制NHE3活性;LY294002抑制上述信号并上调NHE3活性,而WYF可部分逆转LY294002效应并降低NHE3活性。CCKBR沉默后NHE3活性升高,加入GAS后NHE3活性受抑,提示GAS/CCKBR轴参与NHE3调控。结论WYF可能通过调控GAS-CCKBR及其下游PI3K/PLC/PKC依赖性信号,抑制肠上皮NHE3表达,进而减少NHE3介导的Na^(+)/H^(+)交换与Na^(+)吸收,增加肠腔水分并改善排便表型;其因果关系仍需离子通量及特异性阻断实验进一步验证。 展开更多
关键词 温阳益气方 钠氢交换体3 Na^(+)/h^(+)离子转运 胃泌素 胆囊收缩素B受体 慢传输型便秘
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Significance of dormant forms of Helicobacter pylori in ulcerogenesis 被引量:24
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作者 Vasiliy Ivanovich Reshetnyak Tatiana Magomedalievna Reshetnyak 《World Journal of Gastroenterology》 SCIE CAS 2017年第27期4867-4878,共12页
Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ul... Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability. 展开更多
关键词 helicobacter pylori Forms of h. pylori Dormant forms of h. pylori Viable forms of h. pylori Non-viable forms of h. pylori Physiological states of h. pylori Culturable forms of h. pylori Unculturable forms of h. pylor Resuscitation of dormant h. pylori Ulcerogenesis
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基于5W2H分析法的高校图书馆口述历史特藏资源建设路径探析
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作者 高冕 戴子涵 王鹏 《传播与版权》 2026年第2期71-75,共5页
文章运用5W2H分析法,从类型与内容、价值与意义、主体构成与角色分工、空间规划与资源获取、时序规划与进度管理、实施路径、投入与回报等七个维度,对我国高校图书馆口述历史特藏资源建设展开系统分析。基于此,文章提出多方协同采集口... 文章运用5W2H分析法,从类型与内容、价值与意义、主体构成与角色分工、空间规划与资源获取、时序规划与进度管理、实施路径、投入与回报等七个维度,对我国高校图书馆口述历史特藏资源建设展开系统分析。基于此,文章提出多方协同采集口述资源以构建区域性馆藏网络体系、拓宽筹资渠道并加强职业培训、挖掘口述专题资源并整合创新服务等路径,以期为高校图书馆口述历史特藏资源建设的专业性、规范化和可持续性发展提供参考和借鉴。 展开更多
关键词 高校图书馆 口述历史 特藏资源 5W2h分析法
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Iron-catalyzed C-H activation:A sustainable approach to efficient organic synthesis
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作者 Qiao Song Xue Peng +1 位作者 Zhouyu Wang Leyong Wang 《Chinese Chemical Letters》 2025年第5期1-2,共2页
The activation of carbon-hydrogen(C-H)bonds is of great scientific importance and offers broad applications in modern organic chemistry[1].In recent years,strategies for C-H bond activation have made notable advances,... The activation of carbon-hydrogen(C-H)bonds is of great scientific importance and offers broad applications in modern organic chemistry[1].In recent years,strategies for C-H bond activation have made notable advances,particularly in the efficient construction of complex molecular architectures.However,most existing C-H activation systems rely on expensive noble metal catalysts,including palladium,rhodium,ruthenium,and iridium.These metals not only come at a high cost but are also often associated with significant toxicity,which further limits their viability and sustainability in industrial applications. 展开更多
关键词 organic chemistry C h activation carbon hydrogen bonds organic synthesis sustainable approach complex molecular architectures noble metal catalystsincluding iron catalyzed
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H型高血压病人血清CCL21、MIP-1α表达水平及其临床意义
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作者 刘晓艳 金缨 +1 位作者 刘林 贾辉 《中西医结合心脑血管病杂志》 2026年第2期260-264,共5页
目的:探讨趋化因子21(CCL21)、巨噬细胞炎性蛋白1α(MIP-1α)在H型高血压病人血清中的表达水平及临床意义。方法:选取大庆市人民医院2019年9月—2022年9月就诊的原发性高血压病人224例作为研究对象,根据同型半胱氨酸(Hcy)水平将病人分为... 目的:探讨趋化因子21(CCL21)、巨噬细胞炎性蛋白1α(MIP-1α)在H型高血压病人血清中的表达水平及临床意义。方法:选取大庆市人民医院2019年9月—2022年9月就诊的原发性高血压病人224例作为研究对象,根据同型半胱氨酸(Hcy)水平将病人分为H型高血压组(159例)和非H型高血压组(65例);根据H型高血压组Hcy水平将病人分为轻度组(83例)、中度组(42例)、重度组(34例),另选取同期于医院体检的健康人员163名作为对照组。收集研究对象基本资料,采用酶联免疫吸附法(ELISA)检测血清CCL21、MIP-1α水平;随访记录H型高血压病人发生主要心脏不良事件(MACE)的情况。比较各组血清CCL21、MIP-1α水平,采用受试者工作特征(ROC)曲线分析血清CCL21、MIP-1α水平对H型高血压病人发生MACE的预测价值;多因素Logistic回归分析H型高血压病人发生MACE的影响因素。结果:H型高血压组、非H型高血压组与对照组血清CCL21、MIP-1α水平比较,差异均有统计学意义(P<0.05);H型高血压组血清CCL21、MIP-1α水平高于非H型高血压组与对照组,非H型高血压组血清CCL21、MIP-1α水平高于对照组,差异均有统计学意义(P<0.05)。轻度组、中度组和重度组血清CCL21、MIP-1α水平比较,差异有统计学意义(P<0.05);重度组血清CCL21、MIP-1α水平高于中度组与轻度组,中度组血清CCL21、MIP-1α水平高于轻度组,差异均有统计学意义(P<0.05)。MACE组血清CCL21、MIP-1α水平均高于非MACE组,差异均有统计学意义(P<0.05);MACE组病人LDL-C、MAP高于非MACE组,差异有统计学意义(P<0.05)。血清CCL21与MIP-1α单独及联合预测H型高血压病人发生MACE的ROC曲线下面积(AUC)分别为0.826,0.811,0.918,二者联合诊断优于CCL21、MIP-1α单独诊断(Z值分别2.864,3.382,P<0.001)。多因素Logistic回归分析结果表明,CCL21与MIP-1α是影响H型高血压病人发生MACE的危险因素(P<0.001)。结论:H型高血压病人血清CCL21、MIP-1α水平升高与预后密切相关,可能成为H型高血压病人诊断与预后评估的标志物。 展开更多
关键词 h型高血压 趋化因子21 巨噬细胞炎性蛋白1Α
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Spontaneous and Bleomycin-Induced <i>&gamma;</i>H2AX Signals in CHO9 Metaphase Chromosomes
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作者 María Vittoria Di Tomaso Silvia Basso +4 位作者 Laura Lafon-Hughes Gustavo Saona Beatriz López-Carro Ana Laura Reyes-ábalos Pablo Liddle 《Advances in Bioscience and Biotechnology》 2014年第7期603-616,共14页
In eukaryotes, a cascade of events named DNA damage response (DDR) has evolved to handle DNA lesions. DDR engages the recruitment of signaling, checkpoint control, repair and chromatin remodeling protein complexes, al... In eukaryotes, a cascade of events named DNA damage response (DDR) has evolved to handle DNA lesions. DDR engages the recruitment of signaling, checkpoint control, repair and chromatin remodeling protein complexes, allowing cell cycle delay, DNA repair or induction of apoptosis. An early DDR event involves the phosphorylation of the histone variant γH2AX on serine 139 (H2AX139 phosphorylation) originating the so-called γH2AX. DDR-related H2AX139 phosphorylation have been extensively studied in interphase nuclei. More recently, γH2AX signals on mitotic chromosomes of asynchronously growing cell cultures were observed. We performed a quantitative analysis of γH2AX signals on γH2AX immunolabeled cytocentrifuged metaphase spreads, analyzing the γH2AX signal distributions of CHO9 chromosomes harboring homologous regions both in control and bleomycin (BLM)-treated cultures. We detected γH2AX signals in CHO9 chromosomes of controls which significantly increase after BLM-exposure. γH2AX signals were uniformly distributed in chromosomes of controls. However, the γH2AX signal distribution in BLM exposed cells was significantly different between chromosomes and among chromosome regions, with few signals near the centromeres and a tendency to increase towards the telomeres. Interestingly, both basal and BLM-induced γH2AX signal distribution were statistically equal between CHO9 homologous chromosome regions. Our results suggest that BLM exerts an effect on H2AX139 phosphorylation, prevailing towards acetylated and gene-rich distal chromosome segments. The comparable H2AX139 phosphorylation of homologous regions puts forward its dependence on chromatin structure or function and its independence of the position in the karyotype. 展开更多
关键词 h2AX Phosphorylation on Serine 139 γh2AX SIGNALS METAPhASE Chromosomes homologous Chromosome Regions ChO9 Chinese hAMSTER Cell Line
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3,4-二氢-2(1H)喹啉酮衍生物的合成研究 被引量:4
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作者 吴纯鑫 戴立言 +1 位作者 陈英奇 翁志学 《高校化学工程学报》 EI CAS CSCD 北大核心 2003年第5期534-539,共6页
对3,4-二氢-2(1H)喹啉酮衍生物1,2,3(R= NO2,NH2,OH;R= H,NO2,NH2)的合成进行了研究。以苯胺和3-氯丙酰氯为原料,制得N-苯基-3-氯丙酰胺,然后经环合得到3,4-二氢-2(1H)喹啉酮,再经由硝化、还原、重氮化水解合成了一系列3,4-二氢-2(1H)... 对3,4-二氢-2(1H)喹啉酮衍生物1,2,3(R= NO2,NH2,OH;R= H,NO2,NH2)的合成进行了研究。以苯胺和3-氯丙酰氯为原料,制得N-苯基-3-氯丙酰胺,然后经环合得到3,4-二氢-2(1H)喹啉酮,再经由硝化、还原、重氮化水解合成了一系列3,4-二氢-2(1H)喹啉酮衍生物:6-硝基-3,4-二氢-2(1H)喹啉酮(1a),6,8-二硝基-3,4-二氢-2(1H)喹啉酮(1b),6-氨基-3,4-二氢-2(1H)喹啉酮(2a),6,8-二氨基-3,4-二氢-2(1H)喹啉酮(2b),6-氨基-8-硝基-3,4-二氢-2(1H)喹啉酮(2c),6-羟基-3,4-二氢-2(1H)喹啉酮(3a)和6-羟基-8-硝基-3,4-二氢-2(1H)喹啉酮(3b),其中化合物(2c)及(3b)为新化合物。单步产率均在86%以上,路线简单,操作简便,反应条件温和。采用MS,1HNMR对产品进行了定性及结构表征。 展开更多
关键词 3 4-二氢-2(1h)喹啉酮衍生物 6-硝基-3 4-二氢-2(1h)喹啉酮 6 8-二硝基-3 4-二氢-2(1h)喹啉酮 6-氨基-3 4-二氢-2(1h)喹啉酮 6 8-二氨基-3 4-二氢-2(1h)喹啉酮 6-氨基-8-硝基-3 4-二氢-2(1h)喹啉酮 6-羟基-3 4-二 氢-2(1h)喹啉酮 6-羟基-8-硝基-3 4-二
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Liposome-encapsulated 1,4-DPCA enhances anti-tumor immunity and suppresses P3H4-mediated progression in oral squamous cell carcinoma
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作者 Shaochen Nie Yumin Chen +3 位作者 Mei Mei Yuan Zhou Xiao Li Shengjie Jiang 《Nano Research》 2026年第1期874-885,共12页
Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify pr... Oral squamous cell carcinoma(OSCC)is typified by extensive stromal fibrosis and an immunosuppressive microenvironment,both of which impede effective responses to immune checkpoint blockade.In this study,we identify prolyl 3-hydroxylase family member 4(P3H4)as a critical mediator of extracellular matrix(ECM)remodeling,epithelial-mesenchymal transition(EMT),and the exclusion of cytotoxic CD8+T lymphocytes.Elevated P3H4 expression correlates with unfavorable clinical outcomes and resistance to immunotherapy.Genetic ablation of P3H4 significantly attenuates tumor progression and promotes CD8^(+)T cell infiltration.To pharmacologically target P3H4,we engineered a liposomal formulation of 1,4-dihydrophenanthroline-2,5-dicarboxylic acid(1,4-DPCA),a small-molecule prolyl hydroxylase inhibitor.This nanomedicine,designated Lipo-1,4-DPCA,effectively downregulates P3H4 expression,mitigates tumor-associated fibrosis,reprograms the immune microenvironment,and elicits robust anti-tumor responses in vivo.Collectively,our findings establish P3H4 as a promising therapeutic target and highlight Lipo-1,4-DPCA as a dualfunctional nanotherapeutic candidate capable of enhancing the efficacy of immunotherapy in OSCC. 展开更多
关键词 P3h4 extracellular matrix remodeling epithelial-mesenchymal transition Lipo-1 4-DPCA nanomedicine 9
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H–He Demixing Driven by Anisotropic Hydrogen Diffusion 被引量:1
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作者 Xiaoju Chang Dongdong Kang +1 位作者 Bo Chen Jiayu Dai 《Chinese Physics Letters》 2025年第5期33-42,共10页
The dynamics of phase separation in H–He binary systems within gas giants such as Jupiter and Saturn exhibit remarkable complexity, yet lack systematic investigation. Through large-scale machine-learning-accelerated ... The dynamics of phase separation in H–He binary systems within gas giants such as Jupiter and Saturn exhibit remarkable complexity, yet lack systematic investigation. Through large-scale machine-learning-accelerated molecular dynamics simulations spanning broad temperature-pressure-composition(2000–10000 K, 1–7 Mbar,pure H to pure He) regimes, we systematically determine self and mutual diffusion coefficients in H–He systems and establish a six-dimensional framework correlating temperature, pressure, helium abundance, phase separation degree, diffusion coefficients, and anisotropy. Key findings reveal that hydrogen exhibits active directional migration with pronounced diffusion anisotropy, whereas helium passively aggregates in response. While the conventional mixing rule underestimates mutual diffusion coefficients by neglecting velocity cross-correlations,the assumption of an ideal thermodynamic factor(Q = 1) overestimates them due to unaccounted non-ideal thermodynamic effects—both particularly pronounced in strongly phase-separated regimes. Notably, hydrogen's dual role, anisotropic diffusion and bond stabilization via helium doping, modulates demixing kinetics. Large-scale simulations(216,000 atoms) propose novel phase-separation paradigms, such as “hydrogen bubble/wisp” formation, challenging the classical “helium rain” scenario, striving to bridge atomic-scale dynamics to planetary-scale phase evolution. 展开更多
关键词 molecular dynamics simulations gas giants helium diffusion h he systems hydrogen diffusion determine self mutual diffusion coefficients h he binary systems dynamics phase separation
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Targeted activation of junctional adhesion molecule-like protein+CD8+T cells enhances immunotherapy in hepatocellular carcinoma 被引量:1
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作者 Huan Chen Zhaofeng Xiao +3 位作者 Zhengyang Lu Nan Xu Qiang Wei Xiao Xu 《Chinese Journal of Cancer Research》 2025年第2期212-226,共15页
Objective:Cytotoxic T lymphocytes(CTLs)play a crucial role in the therapeutic approach to hepatocellular carcinoma(HCC).Recent research has indicated that junctional adhesion molecule-like protein(JAML)enhances the an... Objective:Cytotoxic T lymphocytes(CTLs)play a crucial role in the therapeutic approach to hepatocellular carcinoma(HCC).Recent research has indicated that junctional adhesion molecule-like protein(JAML)enhances the antitumor activity of CD8+T cells.Our study investigates the role of JAML+CD8+T cells in HCC.Methods:We utilized time-of-flight mass cytometry and an orthotopic mouse model of HCC to examine histone modifications in tumor-infiltrating immune cells undergoing immunotherapy.Flow cytometry was used to assess CD4+T cells differentiation and JAML expression in CD8+T cells infiltrating HCC.Correlation analysis revealed a strong positive correlation between lactate dehydrogenase A+(LDHA+)CD4+T cells and JAML+CD8+T cells.Subsequently,we evaluated the therapeutic effects of an agonistic anti-JAML antibody,both alone and combined with immunotherapy.Finally,RNA sequencing was conducted to identify potential regulatory mechanisms.Results:Immunotherapy significantly increased the percentage of CD8+T cells infiltrating HCC and induced histone modifications,such as H3K18 lactylation(H3K18la)in CD4+T cells.Flow cytometry analysis revealed that lactate promotes the differentiation of CD4+T cells into Th1 cells.LDHA,an enzyme that converts pyruvate to lactate,plays a key role in this process.Correlation analysis revealed a strong positive relationship between LDHA+CD4+T cells and JAML+CD8+T cells in patients who responded to immunotherapy.Moreover,high JAML expression in CD8+T cells was associated with a more favorable prognosis.In vivo experiments demonstrated that agonistic anti-JAML antibody therapy reduced tumor volume and significantly prolonged the survival of tumor-bearing mice,independent of the effects of anti-programmed cell death protein ligand-1 antibody(αPD-L1)-mediated immunotherapy.Pathway enrichment analysis further revealed that JAML enhances CTL responses through the oxidative phosphorylation pathway.Conclusions:Activation of JAML enhances CTL responses in HCC treatment,independent ofαPD-L1-mediated immunotherapy,providing a promising strategy for advanced HCC. 展开更多
关键词 hepatocellular carcinoma IMMUNOThERAPY h3K18la junctional adhesion molecule-like protein oxidative phosphorylation
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核电316H奥氏体不锈钢疲劳损伤机制与温度敏感性研究
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作者 董贺展 余婷 +5 位作者 宋宇轩 王志强 蔡智会 金伟娅 蒋炎尧 高增梁 《材料导报》 北大核心 2026年第2期189-196,共8页
316H奥氏体不锈钢具有优异的高温性能,是第Ⅳ代核电高温气冷堆一回路管道的候选材料之一。然而,其结构构件在高温下仍然存在非预期疲劳开裂现象,亟需深入分析其疲劳失效机制,揭示其高温下的疲劳损伤机理。本工作开展不同温度的316H不锈... 316H奥氏体不锈钢具有优异的高温性能,是第Ⅳ代核电高温气冷堆一回路管道的候选材料之一。然而,其结构构件在高温下仍然存在非预期疲劳开裂现象,亟需深入分析其疲劳失效机制,揭示其高温下的疲劳损伤机理。本工作开展不同温度的316H不锈钢拉伸试验,发现屈服强度与抗拉强度随试验温度的升高逐渐降低,但延伸率则在常温至300℃的范围内随温度的升高而降低,在300~550℃之间出现平台,在550℃以上随试验温度的升高而增大。通过开展常温和高温气冷堆服役温度600℃条件下的316H不锈钢低周疲劳实验,获得了常温与高温下的循环应力-应变特征,分别构建了S-N曲线,通过微观表征技术对拉伸与疲劳的微观组织结构演化、断口形貌进行分析,研究其断裂机理。结果表明:300℃以下晶界结构稳定,主要为穿晶断裂机制;而550℃以上晶界出现析出物,拉伸断口呈现出部分沿晶断裂特征。在常温与高温下均呈现出循环硬化、循环软化、快速失效三个阶段,且高温实验后晶粒尺寸变大,而常温下晶粒无明显变化,但几何必须位错密度(GND)增加明显。此外,常温下疲劳裂纹的启裂机制为滑移带累积导致材料表面出现疲劳裂纹源;而高温下,裂纹启裂位置氧化严重,呈现出疲劳-氧化协同启裂特征。研究结果对高温气冷堆一回路管道的设计、运维与表面强化延寿有重要科学意义。 展开更多
关键词 高温气冷堆 316h奥氏体不锈钢 疲劳 高温 疲劳损伤机制
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H型血管在不同骨骼疾病中研究热点的可视化分析 被引量:2
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作者 彭皓 陈奇刚 申震 《中国组织工程研究》 北大核心 2026年第3期760-769,共10页
背景:H型血管(CD31hiEmcnhi)因独特的功能为深入理解血管介导的骨代谢调控机制提供了新的视角和切入点,引发了骨科学研究范式从“骨本位”向“骨-血管整合”的重要转变。目的:基于H型血管领域的文献数据进行可视化分析,探讨该领域的研... 背景:H型血管(CD31hiEmcnhi)因独特的功能为深入理解血管介导的骨代谢调控机制提供了新的视角和切入点,引发了骨科学研究范式从“骨本位”向“骨-血管整合”的重要转变。目的:基于H型血管领域的文献数据进行可视化分析,探讨该领域的研究热点和前沿趋势。方法:系统检索CNKI和Web of Science核心合集中与H型血管相关的中英文文献,文献检索时限为2014-2024年。采用CiteSpace 6.2.R4信息可视化软件对文献的发表国家、作者、机构、关键词、时间线视图等进行可视化分析。结果与结论:①共纳入中文文献59篇、英文文献185篇。自2014年提出H型血管概念以来,相关研究文献数量逐年增加,中国在该领域的研究处于领先地位,主要研究机构包括南方医科大学、四川大学和上海交通大学等。关键词分析揭示,当前研究热点主要集中在H型血管的生成与调控机制、H型血管在骨生成和骨重塑过程中的作用以及H型血管与骨质代谢相关疾病的关系;此外,出现“诱导膜”“软骨修复”“中医药”等新兴关键词,表明研究正在向多样化和多学科交叉的方向发展。②H型血管在骨骼疾病的发生发展中发挥着关键作用,相关研究对深入理解骨组织的生理与病理过程具有重要意义。未来应进一步探讨H型血管在不同疾病背景下的具体作用机制,推动基础研究成果的临床转化,为骨骼疾病的预防和治疗提供新的思路与策略。 展开更多
关键词 h型血管 骨骼疾病 热点与趋势 CiteSpace 可视化分析 工程化骨材料
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H形钢构件复杂加载下的双向压弯极限状态分析
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作者 吴二强 程欣 +1 位作者 杜辉波 赵金辉 《太原理工大学学报》 北大核心 2026年第1期112-121,共10页
【目的】为获取H形截面钢构件在不同加载路径下的极限状态性能,以弹塑性稳定理论为基础,提出构件的极限状态判定方法。【方法】采用经试验结果校核的ABAQUS有限元建模方法,建立不同宽厚比组配下的H形钢构件在多种加载条件下,包括四种滞... 【目的】为获取H形截面钢构件在不同加载路径下的极限状态性能,以弹塑性稳定理论为基础,提出构件的极限状态判定方法。【方法】采用经试验结果校核的ABAQUS有限元建模方法,建立不同宽厚比组配下的H形钢构件在多种加载条件下,包括四种滞回加载和三种不同地震波时程分析的参数化分析模型。【结果】参数化分析结果验证了极限状态判定方法在双向压弯滞回加载路径和时程分析下的适用性。进一步探究了双向压弯加载下H形钢构件的极限状态发展机理,得到了H形截面钢构件在复杂加载路径下的极限状态破坏特征及规律。为大宽厚比薄柔H形截面钢构件的双向压弯抗震设计方法提供理论基础。 展开更多
关键词 极限状态判定准则 h形截面 双向压弯 滞回加载 时程分析
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