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Functional protection of pentoxifylline against spinal cord ischemia/reperfusion injury in rabbits： necrosis and apoptosis effects

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Chinese Medical Journal 2008年第23期121卷 2444-2449页

作者： ZHU Dan-jie xia bing BI qing ZHANG Shui-jun QIU Bin-song ZHAO Chen Department of Orthopedics Zhejiang Provincial People's Hospital Hangzhou Zhejiang 310014 China

Background Little is known about neuronal death mechanisms following spinal cord ischemia. The present study aimed to investigate the protective effect of pentoxifylline （PTX） against spinal cord ischemia/reperfusion （I/R） injury. Methods Rabbits sustained spinal cord ischemia following 45 minutes cross-clamping of the infrarenal aorta. Experimental groups were as follows： the first group of animals （sham, n=-8） underwent laparotomy alone and served as the sham group; the second group （I/R, n=20） received carrier （3 ml saline solution） and served as the control group; the third group （PTX-A, n=20） received PTX intravenously 10 minutes prior to ischemia; and the fourth group （PTX-B, n=20） received PTX intravenously at the onset of reperfusion. Rabbits were evaluated for hind-limb motor function with the Tarlov scoring system at 48 hours. Serum was assayed with enzyme-linked immunosorbent assay for tumor necrosis factor α （TNF-α） and spinal cords were harvested for myeloperoxidase （MPO） activity, histopathological analysis, terminal deoxynucleotidyl transferase （TdT）-rnediated dUTP nick end labeling staining, platelet/endothelial ceU adhesion molecule-1 （PECAM-1） and caspase-3 immunohistochemistry, and the number of necrotic and apoptotic neuron were counted and data analyzed at 12, 24, 48 and 72 hours of reperfusion. Spinal cords were studied by electron microscopy. Results Improved Tarlov scores were seen in PTX-treated rabbits as compared with ischemic control rabbits at 48 hours. A significant reduction was found in TNF-α in serum, activity of MPO and immunoreactivity of the PECAM-1 and caspase-3 in PTX-treated rabbits. There were fewer apoptotic neurons than necrotic neurons （P 〈0.05）. A significant decrease in both necrotic and apoptotic neurons was observed in the PTX-treated groups （PTX-A and PTX-B） compared with the I/R group （P 〈0.05）. Both necrotic and apoptotic neurons were found with the electron microscope. Conclusions PTX may induce protection aga

关键词： spinal cord injury pentoxifylline necrosis apoptosis

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计算与算计：数据标注劳动中的算法补足组织

社会学评论 2023年第6期11卷 66-86页

作者：吴桐雨夏冰青浙江大学社会学系华东师范大学传播学院

本研究以人工智能数据标注产业为案例，解析中国平台劳动的再嵌入现象。通过分析为期两年的田野调查和154个半结构性访谈资料，构建了“算法补足组织”的概念框架，探讨了“补足组织”如何衔接算法与平台劳动，使之再嵌入回社会关系。... 详细信息

本研究以人工智能数据标注产业为案例，解析中国平台劳动的再嵌入现象。通过分析为期两年的田野调查和154个半结构性访谈资料，构建了“算法补足组织”的概念框架，探讨了“补足组织”如何衔接算法与平台劳动，使之再嵌入回社会关系。由地方政府介入的算法补足组织依据自身组织资源和逻辑，弥合了算法控制所带来的部分潜在劳工问题。在特定情景下，算法补足组织还可能与劳工形成利益同盟，调动组织资源消减算法黑箱特性，联合对抗过度算法控制，这一事实挑战了算法冷漠性等相关理论。

关键词：平台劳动算法控制数据标注人工智能数字劳动

MLKL forms cation channels

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中国药理学与毒理学杂志 2016年第10期30卷 1047-1047页

作者： xia bing-qing FANG Sui CHEN Xue-qin HU Hong CHEN Pei-yuan WANG Hua-yi GAO Zhao-bing State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences

The mixed lineage kinase domain-like(MLKL)protein is a key factor in tumor necrosis factor-induced *** studies on necroptosis execution revealed a commitment role of MLKL in membrane ***,our knowledge of how MLKL functions on membrane remains very *** we demonstrate that MLKL forms cation channels that are permeable preferential y to Mg2+rather than Ca2+in the presence of Na+and K+.Moreover,the N-terminal domain containing six helices(H1-H6)is sufficient to form *** the substituted cysteine accessibility method,we further determine that helix H1,H2,H3,H5 and H6 are transmembrane segments,while H4 is located in the ***,MLKL-induced membrane depolarization and cell death exhibit a positive correlation to its channel *** Mg2+-preferred permeability and five transmembrane segment topology distinguish MLKL from previously identified Mg2+-permeable channels and thus establish MLKL as a novel class of cation channels.

关键词： cation channels mixed lineage kinase domain-like

机械合金化结合热压制备不同Si含量硅铝合金的摩擦磨损性能

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粉末冶金材料科学与工程 2013年第5期18卷 669-674页

作者：窦玉海刘咏刘延斌夏庆兵中南大学粉末冶金国家重点实验室长沙410083

通过机械合金化结合热压致密化的工艺制备Al-30Si、Al-40Si、Al-50Si 3种成分的高硅铝合金,采用金相、SEM、EDS、压缩实验、摩擦磨损试验等对合金的组织、抗压强度及摩擦磨损性能等进行研究。结果表明:合金显微组织中呈现Al相富集区、S... 详细信息

通过机械合金化结合热压致密化的工艺制备Al-30Si、Al-40Si、Al-50Si 3种成分的高硅铝合金,采用金相、SEM、EDS、压缩实验、摩擦磨损试验等对合金的组织、抗压强度及摩擦磨损性能等进行研究。结果表明:合金显微组织中呈现Al相富集区、Si相富集区和铝硅混合区3种区域,且合金中Si颗粒细小,没有明显长大的现象。合金的抗压强度随Si含量的增加先升高后降低。Al-40Si合金具有最佳的耐磨性和减摩性,其磨损机理主要是磨粒磨损和氧化磨损。除磨粒磨损外,Al-30Si合金磨损初期存在粘着磨损,后期则以氧化磨损为主,而Al-50Si则存在较严重的剥层磨损。

关键词：高硅铝合金机械合金化热压抗压强度摩擦磨损性能

机械合金化结合热压制备高硅铝合金的组织及性能

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粉末冶金材料科学与工程 2013年第4期18卷 566-571页

作者：窦玉海刘咏刘延斌夏庆兵徐菲中南大学粉末冶金国家重点实验室长沙410083

采用机械合金化结合热压的工艺制备Al-30Si、Al-40Si、Al-50Si三种成分的高硅铝合金,通过扫描电镜(SEM)、能谱分析仪(EDS)、X射线衍射仪(XRD)、密度及布式硬度测定仪等对机械合金化粉末的形貌及其演化,以及热压块体的组织与性能进行研... 详细信息

采用机械合金化结合热压的工艺制备Al-30Si、Al-40Si、Al-50Si三种成分的高硅铝合金,通过扫描电镜(SEM)、能谱分析仪(EDS)、X射线衍射仪(XRD)、密度及布式硬度测定仪等对机械合金化粉末的形貌及其演化,以及热压块体的组织与性能进行研究。结果表明:机械合金化8h的粉末细化效果较好,氧含量较低;合金的致密度随Si含量的增加逐渐降低;合金组织呈现Al相富集区和Si相富集区,Si颗粒粒径小于5μm,没有出现明显长大现象;Al2O3、SiO2等氧化物颗粒分布在铝硅界面和基体中;合金的布氏硬度随Si含量的增加先升高后降低;Al-40Si的硬度高达144 HB,比压力熔渗法制得的Al-40Si高50%。因此,机械合金化结合热压致密化的制备工艺可显著提高高硅铝合金的力学性能。

关键词：高硅铝合金机械合金化热压力学性能

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing Xue Yuejia Ma Ke Ye Xue Zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang qing xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

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高中英语课堂教师话语重复的调查与分析

湖南广播电视大学学报 2013年第2期 76-79页

作者：夏冰清李湄江西师范大学外国语学院江西南昌330022

重复是话语结构中的重要组成部分。为了了解英语教师课堂话语重复的现状,本研究采用课堂录音的方式,以课堂实录转写成的文字材料为语料,对教师课堂话语重复的四个维度进行分析。结果表明:英语教师在高中课堂中还是存在话语重复的随意性... 详细信息

重复是话语结构中的重要组成部分。为了了解英语教师课堂话语重复的现状,本研究采用课堂录音的方式,以课堂实录转写成的文字材料为语料,对教师课堂话语重复的四个维度进行分析。结果表明:英语教师在高中课堂中还是存在话语重复的随意性和简单化等问题;教师应正视不恰当的话语重复,优化教师话语;教师应提升话语重复的科学性和实效性,从而促进课堂教学效果和学生的二语习得。

关键词：高中英语英语教师话语重复

Near-infrared organic photosensitizers with aggregation-induced emission and switchable fluorescence for fungal infection therapy

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Science China Chemistry 2025年

作者： Xinzhe Yang Zixuan Huang Keke Ding Huili Yang Lirong Wang qing xia Rong Hu Guang Shi bingjia Xu Anjun Qin School of Chemistry South China Normal University State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute South China University of Technology Department of Urology The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College) School of Chemistry and Chemical Engineering University of South China

The development of near-infrared (NIR) photosensitizers with aggregation-induced emission (AIE) properties,switchable luminescence colors,and satisfactory photodynamic therapy (PDT) effects on the treatment of fungal infection is of great importance but very ***,two ionic organic luminogens are constructed by employing diphenylamine,diphenylacrylonitrile/1,2-diphenylethene,and methylated quinoline cation as building *** is found that the resulting compounds TCQF and TQF show apparent AIE properties and produce intense fluorescence with high photoluminescence quantum yields of up to 31.2%in the solid *** the meantime,their emission colors can be switched between red and NIR and in the NIR region by mechanical force and solvent vapor,respectively,thereby enabling remarkable and reversible mechanochromism with emission variations of up to 104 *** excitingly,TCQF and TQF can efficiently generate ROS under the illumination of white light and show excellent antimicrobial activities and satisfactory PDT *** by the unique anti-fungus properties,TCQF is employed as a biocompatible NIR photosensitizer for treating wound infection with ***,and apparent PDT effects are *** work provides a new direction for the development of multifunctional NIR materials with AIE properties.

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薄壁钢-混凝土组合墙板的剪切屈曲分析

建筑技术开发 2013年第2期40卷 9-12页

作者：夏冰青戴卜云董军南京工程学院建筑工程学院南京216667 南京工业大学土木工程学院南京210009 江苏省化工设计院有限公司南京210024

研究了设置自攻螺钉连接件的薄壁钢-混凝土组合墙板中钢面板的受剪屈曲问题。栓钉的设置有效抑制了钢板过早发生局部屈曲,提高了组合板的承载能力。提出新的位移函数,利用能量法分析钢面板的受剪屈曲,分析了屈曲系数随栓钉间距变化的规... 详细信息

研究了设置自攻螺钉连接件的薄壁钢-混凝土组合墙板中钢面板的受剪屈曲问题。栓钉的设置有效抑制了钢板过早发生局部屈曲,提高了组合板的承载能力。提出新的位移函数,利用能量法分析钢面板的受剪屈曲,分析了屈曲系数随栓钉间距变化的规律。针对板件的不同使用功能要求,给出了各种厚度板件的栓钉间距限值,供设计参考。

关键词：组合墙板钢面板剪切屈曲能量法