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The Effect of Coding Method on Cause-of-Death Rankings
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作者 Peter Harteloh 《Open Journal of Statistics》 2023年第6期778-788,共11页
Background: Cause-of-death rankings are often used for planning or evaluating health policy measures. In the European Union, some countries produce cause-of-death statistics by a manual coding of death certificates, w... Background: Cause-of-death rankings are often used for planning or evaluating health policy measures. In the European Union, some countries produce cause-of-death statistics by a manual coding of death certificates, while other countries use an automated coding system. The outcome of these two different methods in terms of the selected underlying cause of death for statistics may vary considerably. Therefore, this study explores the effect of coding method on the ranking of countries by major causes of death. Method: Age and sex standardized rates were extracted for 33 European (related) countries from the cause-of-death registry of the European Statistical Office (Eurostat). Wilcoxon’s rank sum test was applied to the ranking of countries by major causes of death. Results: Statistically significant differences due to coding method were identified for dementia, stroke and pneumonia. These differences could be explained by a different selection of dementia or pneumonia as underlying cause of death and by a different certification practice for stroke. Conclusion: Coding method should be taken into account when constructing or interpreting rankings of countries by cause of death. 展开更多
关键词 Cause-of-Death Statistics Cause of Death RANKING Automated Coding Manual Coding EPIDEMIOLOGY Health Policy
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Efficiency Rankings of MBA Programs in Indian Top Public Colleges 被引量:3
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作者 Patrick Jaska Vedamuthu Kulandai Swamy 《Journal of Modern Accounting and Auditing》 2013年第9期1275-1279,共5页
This study examines the relative efficiency of the top 20 Indian public colleges that offer MBAs. These colleges were chosen from a list provided by Careers 360, a magazine in India known for its university rankings. ... This study examines the relative efficiency of the top 20 Indian public colleges that offer MBAs. These colleges were chosen from a list provided by Careers 360, a magazine in India known for its university rankings. The purpose of this study was to evaluate the colleges on an efficiency basis rather than on a total score ranking scale as is the common practice of most publications that rank universities or programs. The ranking method used in this study is based on data envelopment analysis (DEA), a nonparametric procedure for evaluating entities based upon examining inputs in relation to outputs achieved. The rankings using DEA were somewhat different than those given by Careers 360. The results of the DEA analysis of this study rank the universities that are the most efficient at getting students the best salaries and return on investment (ROI) based on the inputs of diversity, work experience, and residency. The authors conclude, as previous studies have shown, that DEA analysis is a useful and non-biased method of comparing university programs. 展开更多
关键词 aniversity academic rankings relative efficiency data envelopment analysis (DEA)
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Subject Area Risk Assessment of Four Hungarian Universities with a View to the QS University Rankings by Subject
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作者 Péter Sasvári Anna Urbanovics 《Journal of Data and Information Science》 CSCD 2022年第4期61-80,共20页
Purpose:The aim of our paper is to investigate the role of a mentor leading a research team in the overall scientific performance of an academic institution and the possible risks of their departure with a special att... Purpose:The aim of our paper is to investigate the role of a mentor leading a research team in the overall scientific performance of an academic institution and the possible risks of their departure with a special attention to their publication output.Design/methodology/approach:By using SciVal subject area data,we composed a formula describing the level of vulnerability of any given university in the case of losing any of its leading mentors,identifying other risk factors by dividing their careers into separate stages.Findings:It turns out that the higher field-weighed citation impact is,the better position universities reach in the rankings by subject and the vulnerability of institutions highly depends on the mentors,especially in view of their contribution to the topic clusters.Research limitations:The analysis covers the publication output of leading researchers working at four Hungarian universities,the scope of the analysis is worth being extended.Practical implications:Our analysis has the potential to give an applicable systemic approach as well as a data collection scheme to university managements so as to formulate an inclusive and comprehensive research strategy involving the introduction of a reward system aimed at publications and further encouraging national and international research cooperation.Originality/value:The methodology and the principles of risk assessment laid down in our paper are not restricted to measuring the vulnerability level of a limited group of academic institutions,they can be appropriately used for investigating the role of mentors or leading researchers at every university across the globe. 展开更多
关键词 QS rankings by Subject Scientific Competitiveness Risk Analysis Subject Area Exposure
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Switzerland Replaces United States at Top of Competitiveness Rankings
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《China Textile》 2009年第10期18-19,共2页
On Sep. 8,2009,Switzerland tops the overall ranking in The Global Competitiveness Report 2009-2010, released by the World Economic Forum ahead of its Annual Meeting of the New Champions 2009 in Dalian.
关键词 World Switzerland Replaces United States at Top of Competitiveness rankings
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Are University Rankings Statistically Significant?A Comparison among Chinese Universities and with the USA 被引量:1
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作者 Loet Leydesdorff Caroline SWagner Lin Zhang 《Journal of Data and Information Science》 CSCD 2021年第2期67-95,共29页
Purpose:Building on Leydesdorff,Bornmann,and Mingers(2019),we elaborate the differences between Tsinghua and Zhejiang University as an empirical example.We address the question of whether differences are statistically... Purpose:Building on Leydesdorff,Bornmann,and Mingers(2019),we elaborate the differences between Tsinghua and Zhejiang University as an empirical example.We address the question of whether differences are statistically significant in the rankings of Chinese universities.We propose methods for measuring statistical significance among different universities within or among countries.Design/methodology/approach:Based on z-testing and overlapping confidence intervals,and using data about 205 Chinese universities included in the Leiden Rankings 2020,we argue that three main groups of Chinese research universities can be distinguished(low,middle,and high).Findings:When the sample of 205 Chinese universities is merged with the 197 US universities included in Leiden Rankings 2020,the results similarly indicate three main groups:low,middle,and high.Using this data(Leiden Rankings and Web of Science),the z-scores of the Chinese universities are significantly below those of the US universities albeit with some overlap.Research limitations:We show empirically that differences in ranking may be due to changes in the data,the models,or the modeling effects on the data.The scientometric groupings are not always stable when we use different methods.Practical implications:Differences among universities can be tested for their statistical significance.The statistics relativize the values of decimals in the rankings.One can operate with a scheme of low/middle/high in policy debates and leave the more fine-grained rankings of individual universities to operational management and local settings.Originality/value:In the discussion about the rankings of universities,the question of whether differences are statistically significant,has,in our opinion,insufficiently been addressed in research evaluations. 展开更多
关键词 RANKING UNIVERSITY China Significance of differences INDICATORS
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Does a Country/Region's Economic Status Affect Its Universities' Presence in International Rankings?
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作者 Esteban Fernandez Tuesta Carlos Garcia-Zorita +1 位作者 Rosario Romera Ayllon Elias Sanz-Casado 《Journal of Data and Information Science》 CSCD 2019年第2期56-78,共23页
Purpose: Study how economic parameters affect positions in the Academic Ranking of World Universities' top 500 published by the Shanghai Jiao Tong University Graduate School of Education in countries/regions with ... Purpose: Study how economic parameters affect positions in the Academic Ranking of World Universities' top 500 published by the Shanghai Jiao Tong University Graduate School of Education in countries/regions with listed higher education institutions. Design/methodology/approach: The methodology used capitalises on the multi-variate characteristics of the data analysed. The multi-colinearity problem posed is solved by running principal components prior to regression analysis, using both classical(OLS) and robust(Huber and Tukey) methods. Findings: Our results revealed that countries/regions with long ranking traditions are highly competitive. Findings also showed that some countries/regions such as Germany, United Kingdom, Canada, and Italy, had a larger number of universities in the top positions than predicted by the regression model. In contrast, for Japan, a country where social and economic performance is high, the number of ARWU universities projected by the model was much larger than the actual figure. In much the same vein, countries/regions that invest heavily in education, such as Japan and Denmark, had lower than expected results.Research limitations: Using data from only one ranking is a limitation of this study, but the methodology used could be useful to other global rankings. Practical implications: The results provide good insights for policy makers. They indicate the existence of a relationship between research output and the number of universities per million inhabitants. Countries/regions, which have historically prioritised higher education, exhibited highest values for indicators that compose the rankings methodology; furthermore,minimum increase in welfare indicators could exhibited significant rises in the presence of their universities on the rankings.Originality/value: This study is well defined and the result answers important questions about characteristics of countries/regions and their higher education system. 展开更多
关键词 Academic Ranking of World Universities Socio-economic indicators Regression analysis
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Rankings of Universities and Power in the Digital Age
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作者 Mario Alberto Velazquez Garcia Lilian lvetthe Salado Rodriguez 《Sociology Study》 2015年第4期269-281,共13页
This paper will discuss one topic in the current debate on higher education: How power is exercised between universities? How do colleges determine what the best college is? What are the differences in the excersis... This paper will discuss one topic in the current debate on higher education: How power is exercised between universities? How do colleges determine what the best college is? What are the differences in the excersise of power in the digital age? The authors analyze one of the mechanisms of relationship and contact between different universities: the rankings. They will discuss the practices that allow certain values and organizations they are becoming central nodes between universities and the influences of the information and communication technologies in the measurement mechanisms. The authors seek to show the rankings serve as mechanisms to exercise power among universities. These measurements become a tool and justification in competition between universities for resources such as funding, prestige, and student demand. The analysis is based on the University of Mexico, the authors use the ranking of the best universities in Latin America and the best universities in Mexico. 展开更多
关键词 TECHNOLOGY POWER UNIVERSITY RANKING Mexico
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全氟辛酸对成骨细胞骨形成和破骨细胞骨吸收作用研究
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作者 薛黎明 林元杰 +3 位作者 金玉娥 徐佳乐 卢大胜 汪国权 《日用化学工业(中英文)》 CAS 北大核心 2024年第6期648-655,共8页
考察全氟辛酸(PFOA)对成骨细胞骨形成和破骨细胞骨吸收的作用和机制,为探索PFOA暴露引起骨丢失提供科学依据。采用原代新生大鼠颅盖骨分离成骨细胞,考察1,10和100μmol/L PFOA对成骨细胞增殖,碱性磷酸酶(ALP)活性和骨结节形成的影响;采... 考察全氟辛酸(PFOA)对成骨细胞骨形成和破骨细胞骨吸收的作用和机制,为探索PFOA暴露引起骨丢失提供科学依据。采用原代新生大鼠颅盖骨分离成骨细胞,考察1,10和100μmol/L PFOA对成骨细胞增殖,碱性磷酸酶(ALP)活性和骨结节形成的影响;采用巨噬细胞集落刺激因子(M-CSF)及核因子κB受体激活因子配体(RANKL)诱导大鼠骨髓单核细胞分化破骨细胞模型,考察1,10和100μmol/L PFOA对破骨细胞活力,抗酒石酸酸性磷酸酶(TRAP)活性和骨吸收陷窝形成指标的影响;采用Western blot考察成骨细胞护骨素(OPG)和RANKL蛋白表达。PFOA在1和10μmol/L时促进成骨细胞活力,但对ALP活性和骨结节形成无影响。100μmol/L PFOA可显著抑制细胞增殖,ALP活性和骨结节形成,同时抑制OPG/RANKL蛋白表达的比例。PFOA对破骨细胞活力无影响,10和100μmol/L PFOA可显著抑制促进TRAP活性和骨吸收陷窝形成面积。PFOA抑制成骨细胞骨形成作用可能通过下调Wnt通路,通过抑制OPG/RANKL/RANK通路,促进破骨细胞骨吸收作用。 展开更多
关键词 全氟辛酸 骨丢失 成骨细胞 破骨细胞 OPG/RANKL/RANK通路
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酒花提取物调控Wnt/β-catenin信号通路对去卵巢骨质疏松大鼠的作用及机制研究
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作者 李敏 扎克艳·地力夏提 +1 位作者 胡君萍 杨建华 《中药新药与临床药理》 CAS CSCD 北大核心 2024年第9期1337-1343,共7页
目的探讨酒花提取物对去卵巢骨质疏松大鼠的作用及机制。方法将60只雌性SD大鼠随机分为假手术组、模型组、阳性对照组(戊酸雌二醇,0.105 mg·kg^(-1))和酒花提取物低、中、高剂量组(65.625、131.120、196.875 mg·kg^(-1)),每... 目的探讨酒花提取物对去卵巢骨质疏松大鼠的作用及机制。方法将60只雌性SD大鼠随机分为假手术组、模型组、阳性对照组(戊酸雌二醇,0.105 mg·kg^(-1))和酒花提取物低、中、高剂量组(65.625、131.120、196.875 mg·kg^(-1)),每组10只。除假手术组外,其余各组大鼠均切除双侧卵巢,术后灌胃给药,每日1次,连续给药90 d。采用HE染色法观察大鼠骨组织病理形态变化,测定骨形态计量学参数,计算骨小梁数目(Tb.N)、骨小梁厚度(Tb.Th)、骨小梁分离度(Tb.Sp)和骨小梁面积百分数(Tb.Ar);测定大鼠骨组织生物力学指标:最大载荷、弹性模量、断裂强度;采用ELISA法测定大鼠血清雌激素(E_(2))、抗酒石酸酸性磷酸酶(TRACP5b)、骨钙素(OC)、骨特异性碱性磷酸酶(BALP)含量;采用全自动生化仪测定大鼠血清碱性磷酸酶(ALP)含量;采用RT-PCR及Western Blot法检测大鼠胫骨组织OPG、RANKL、ERα、ERβ、Wnt16、β-catenin mRNA及蛋白表达水平。结果与假手术组相比,模型组大鼠胫骨骨小梁断裂,骨髓腔变大,呈现骨质疏松结构;胫骨Tb.N、Tb.Th、Tb.Ar明显降低(P<0.05),Tb.Sp明显升高(P<0.05);股骨的最大载荷、弹性模量和断裂强度均明显降低(P<0.05);血清E_(2)含量明显降低(P<0.05),TRACP5b、OC、ALP、BALP含量均明显升高(P<0.05);胫骨组织的OPG、OPG/RANKL、ERα、ERβ、β-catenin、Wnt16 mRNA及蛋白表达明显下调(P<0.05),RANKL mRNA及蛋白表达明显上调(P<0.05)。与模型组相比,阳性对照组及酒花提取物高剂量组的上述指标均明显回调(P<0.05)。结论酒花提取物对绝经后骨质疏松症具有一定的防治作用,其作用机制可能与调控Wnt/β-catenin信号通路,进而调控OPG/RANK/RANKL信号通路有关。 展开更多
关键词 酒花提取物 骨质疏松症 去卵巢大鼠 WNT/Β-CATENIN信号通路 OPG/RANK/RANKL信号通路
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OPG/RANKL/RANK信号通路在脓毒症相关急性肾损伤小鼠中的研究
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作者 李辉 陈蔚霖 牛新荣 《海南医学院学报》 CAS 北大核心 2024年第3期168-174,共7页
目的:探讨骨保护素(OPG)/核因子⁃κB受体活化因子配体(RANKL)/核因子⁃κB受体激活因子(RANK)信号通路因子在脓毒症相关急性肾损伤(SA⁃AKI)小鼠中的改变及可能的作用,为SA⁃AKI的机制研究探索新的思路。方法:通过盲肠结扎穿孔手术(CLP)建... 目的:探讨骨保护素(OPG)/核因子⁃κB受体活化因子配体(RANKL)/核因子⁃κB受体激活因子(RANK)信号通路因子在脓毒症相关急性肾损伤(SA⁃AKI)小鼠中的改变及可能的作用,为SA⁃AKI的机制研究探索新的思路。方法:通过盲肠结扎穿孔手术(CLP)建立SA⁃AKI模型组(CLP组),对照组为假手术组(Sham组),只行开腹不做盲肠结扎穿孔操作。术后24 h采血并处死留取小鼠肾脏组织,用试剂盒检测血清Scr、BUN水平,酶联免疫测定法(ELISA)检验血清中IL⁃6、TNF⁃α、IL⁃1β水平,苏木精⁃伊红染色(HE)观测肾组织病理学变化,聚合酶链反应(RT⁃qPCR)和蛋白质印迹实验(Western blotting)检验小鼠肾组织中OPG、RANKL、RANK的mRNA和蛋白水平。结果:与Sham组对比,CLP组Scr、BUN、IL⁃6、TNF⁃α、IL⁃1β水平显著升高,差异均具有统计学意义(P<0.05);与Sham组对比,CLP组肾小球充血水肿,部分缺血皱缩,球囊间隙扩大,部分肾小管中可见坏死的上皮细胞,管腔扩大,肾间质水肿,少量炎性细胞浸润;与Sham组相比较,CLP组肾组织中OPG和RANK的mRNA表达显著上调,而RANKL的mRNA表达明显下降,差异均具有统计学意义(P<0.05);与Sham组相比较,CLP组肾脏组织中OPG及RANK的蛋白表达均升高,而RANKL的蛋白表达明显下降,差异均具有统计学意义(P<0.05)。结论:在脓毒症的小鼠模型中OPG及RANK表达升高,RANKL表达下降,表明OPG/RANKL/RANK信号通路可能参与了SA⁃AKI的病理生理过程。 展开更多
关键词 脓毒症 急性肾损伤 OPG/RANKL/RANK信号通路
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miR-26a在血管钙化中的作用机制
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作者 吴伟 尚玉强 +2 位作者 程龙 王杰 杨传蕾 《中国老年学杂志》 CAS 北大核心 2024年第4期893-896,共4页
目的探讨血管钙化过程中miR-26a表达差异及其作用机制。方法通过体内和体外实验构建血管钙化模型,利用分子生物学、病理生物学及细胞生物学检测方法,验证血管钙化过程中miR-26a表达差异及可能作用机制。结果与模型组和mimic NC组相比较,... 目的探讨血管钙化过程中miR-26a表达差异及其作用机制。方法通过体内和体外实验构建血管钙化模型,利用分子生物学、病理生物学及细胞生物学检测方法,验证血管钙化过程中miR-26a表达差异及可能作用机制。结果与模型组和mimic NC组相比较,miR-26a mimic组碱性磷酸酶活性显著降低(P<0.05)。而inhibitor NC组和miR-26a inhibitor组碱性磷酸酶无显著变化(P>0.05)。与mimic NC组比较,miR-26a mimic组miR-26a、骨保护素(OPG)表达水平显著升高(P<0.05),而骨桥蛋白(OPN)、骨形态发生蛋白(BMP)-2和胶原蛋白(Collagen)Ⅱ表达水平显著降低(P<0.05)。与inhibitor NC组比较,miR-26a inhibitor组miR-26a、OPG、OPN、BMP-2和CollagenⅡ表达水平无显著差异(P>0.05)。结论miR-26a在血管钙化中的作用机制可能与OPG/核因子κB受体激活剂(RANK)/细胞核因子κB受体活化因子配体(RANKL)信号通路有关。 展开更多
关键词 miR-26a 骨保护素(OPG)/核因子κB受体激活剂(RANK)/细胞核因子κB受体活化因子配体(RANKL)信号通路 血管钙化
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膝关节置换术后患者血清RANKL、sVCAM-1、ESR表达水平及其与预后的相关性
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作者 张文 杨卫兵 《中国骨科临床与基础研究杂志》 2024年第3期183-188,共6页
目的 探讨膝关节置换术后患者血清核因子-κB受体活化因子配基(RANKL)、可溶性血管细胞黏附分子-1(sVCAM-1)、红细胞沉降率(ESR)的表达意义及其与预后的关系。方法 回顾性分析2020年1月至2022年9月安阳市人民医院收治的118例膝关节置换... 目的 探讨膝关节置换术后患者血清核因子-κB受体活化因子配基(RANKL)、可溶性血管细胞黏附分子-1(sVCAM-1)、红细胞沉降率(ESR)的表达意义及其与预后的关系。方法 回顾性分析2020年1月至2022年9月安阳市人民医院收治的118例膝关节置换手术患者的临床资料,根据术后6个月Lysholm评分将患者分为预后不良组(总分<70分,27例)和预后良好组(总分≥70分,91例)。比较两组术后1、3个月血清RANKL、sVCAM-1、ESR表达水平,分析其与Lysholm评分的相关性,评估上述血清学指标联合检测对患者术后预后不良的预测价值。结果 术后1、3个月预后不良组血清RANKL、sVCAM-1、ESR水平高于预后良好组(P <0.05),术后1、3个月血清RANKL、sVCAM-1、ESR水平与Lysholm评分呈负相关(P <0.05),联合预测患者术后预后不良的曲线下面积(AUC)优于各血清指标单独预测(P <0.05)。结论 血清RANKL、sVCAM-1、ESR水平升高可提示膝关节置换术患者预后不良风险的增加,联合检测可作为预测预后不良、判断病情转归的参考依据。 展开更多
关键词 关节成形术 置换 预后 RANK配体 血管细胞黏附分子1 血沉
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脱氢胆酸调控OPG/RANK和TRAF3抑制破骨细胞分化 被引量:2
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作者 朱禹潼 张晓楠 +1 位作者 关溪 尚东 《中国骨质疏松杂志》 CAS CSCD 北大核心 2024年第1期12-16,共5页
目的探讨脱氢胆酸(dehydrocholic acid,DHCA)对破骨细胞(osteoclasts,OCs)分化及功能的影响。方法采用粒细胞-巨噬细胞集落刺激因子和核因子κB受体活化因子配体(receptor activator of nuclear factor kappa B(NF-κB)-ligand,RANKL)... 目的探讨脱氢胆酸(dehydrocholic acid,DHCA)对破骨细胞(osteoclasts,OCs)分化及功能的影响。方法采用粒细胞-巨噬细胞集落刺激因子和核因子κB受体活化因子配体(receptor activator of nuclear factor kappa B(NF-κB)-ligand,RANKL)诱导成熟骨髓来源的巨噬细胞分化为OCs。通过抗酒石酸酸性磷酸酶(tartrate-resistant acid phosphatase,TRAP/ACP5)染色,确定DHCA抑制OCs形成的最佳浓度。qRT-PCR检测OCs分化和功能相关基因TRAP/ACP5、组织蛋白酶K(cathepsin K,CTSK)和基质金属蛋白酶9(matrix metalloproteinase 9,MMP9)的基因表达。Western blot检测OCs中TNF受体相关因子3(TNF receptor-associated factor 3,TRAF3)、NF-κB受体活化因子(receptor activator of NF-κB,RANK)和骨保护素(osteoprotegerin,OPG)的蛋白水平。结果DHCA浓度为200μmol/L是抑制OCs形成的最佳剂量(P<0.01)。DHCA抑制OCs分化和功能相关基因ACP5、CTSK和MMP9的表达(P<0.01)。DHCA通过下调RANK蛋白和增加TRAF3和OPG蛋白的表达来抑制OCs的分化(P<0.01)。结论DHCA通过调控OPG/RANK和TRAF3抑制OCs分化,这可能是一种有效的骨质疏松前体药物。 展开更多
关键词 脱氢胆酸 破骨细胞 OPG/RANK TRAF3 骨质疏松
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Geological characteristics and exploration breakthroughs of coal rock gas in Carboniferous Benxi Formation,Ordos Basin,NW China 被引量:2
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作者 ZHAO Zhe XU Wanglin +8 位作者 ZHAO Zhenyu YI Shiwei YANG Wei ZHANG Yueqiao SUN Yuanshi ZHAO Weibo SHI Yunhe ZHANG Chunlin GAO Jianrong 《Petroleum Exploration and Development》 SCIE 2024年第2期262-278,共17页
To explore the geological characteristics and exploration potential of the Carboniferous Benxi Formation coal rock gas in the Ordos Basin,this paper presents a systematic research on the coal rock distribution,coal ro... To explore the geological characteristics and exploration potential of the Carboniferous Benxi Formation coal rock gas in the Ordos Basin,this paper presents a systematic research on the coal rock distribution,coal rock reservoirs,coal rock quality,and coal rock gas features,resources and enrichment.Coal rock gas is a high-quality resource distinct from coalbed methane,and it has unique features in terms of burial depth,gas source,reservoir,gas content,and carbon isotopic composition.The Benxi Formation coal rocks cover an area of 16×104km^(2),with thicknesses ranging from 2 m to 25 m,primarily consisting of bright and semi-bright coals with primitive structures and low volatile and ash contents,indicating a good coal quality.The medium-to-high rank coal rocks have the total organic carbon(TOC)content ranging from 33.49%to 86.11%,averaging75.16%.They have a high degree of thermal evolution(Roof 1.2%-2.8%),and a high gas-generating capacity.They also have high stable carbon isotopic values(δ13C1of-37.6‰to-16‰;δ13C2of-21.7‰to-14.3‰).Deep coal rocks develop matrix pores such as gas bubble pores,organic pores,and inorganic mineral pores,which,together with cleats and fractures,form good reservoir spaces.The coal rock reservoirs exhibit the porosity of 0.54%-10.67%(averaging 5.42%)and the permeability of(0.001-14.600)×10^(-3)μm^(2)(averaging 2.32×10^(-3)μm^(2)).Vertically,there are five types of coal rock gas accumulation and dissipation combinations,among which the coal rock-mudstone gas accumulation combination and the coal rock-limestone gas accumulation combination are the most important,with good sealing conditions and high peak values of total hydrocarbon in gas logging.A model of coal rock gas accumulation has been constructed,which includes widespread distribution of medium-to-high rank coal rocks continually generating gas,matrix pores and cleats/fractures in coal rocks acting as large-scale reservoir spaces,tight cap rocks providing sealing,source-reservoir integration,and five types of efficient enrichment patterns(lateral pinchout complex,lenses,low-amplitude structures,nose-like structures,and lithologically self-sealing).According to the geological characteristics of coal rock gas,the Benxi Formation is divided into 8 plays,and the estimated coal rock gas resources with a buried depth of more than 2000 m are more than 12.33×10^(12)m^(3).The above understandings guide the deployment of risk exploration.Two wells drilled accordingly obtained an industrial gas flow,driving the further deployment of exploratory and appraisal wells.Substantial breakthroughs have been achieved,with the possible reserves over a trillion cubic meters and the proved reserves over a hundred billion cubic meters,which is of great significance for the reserves increase and efficient development of natural gas in China. 展开更多
关键词 coal rock gas coalbed methane medium-to-high rank coal CLEAT Ordos Basin Carboniferous Benxi Formation risk exploration
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基于RANKL/RANK/OPG信号轴探讨骨痹通消颗粒对激素性股骨头坏死模型小鼠的治疗作用
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作者 方祥 周正新 +3 位作者 朱磊 芮仞 许茂玉 朱彩玉 《中国现代医学杂志》 CAS 2024年第7期27-33,共7页
目的观察骨痹通消颗粒对激素性股骨头坏死模型小鼠的治疗作用,并从核因子-κB受体活化因子配体/核因子-κB受体活化因子/骨保护素(RANKL/RANK/OPG)信号轴探讨其作用机制。方法采取腹腔注射脂多糖和臀肌注射醋酸泼尼松龙复制激素性股骨... 目的观察骨痹通消颗粒对激素性股骨头坏死模型小鼠的治疗作用,并从核因子-κB受体活化因子配体/核因子-κB受体活化因子/骨保护素(RANKL/RANK/OPG)信号轴探讨其作用机制。方法采取腹腔注射脂多糖和臀肌注射醋酸泼尼松龙复制激素性股骨头缺血坏死(SONFH)动物模型,经核磁共振鉴定后,将模型复制成功的60只小鼠分成模型(MC)组、骨痹通消颗粒(GBTX)组及通络生骨胶囊(PC)组,每组20只,另设12只正常小鼠作为空白对照(NC)组。分别予以对应组灌胃相应药物12周后麻醉状态下取材,观察各组小鼠治疗前后的一般行为;酶联免疫吸附试验(ELISA)检测各组小鼠的骨碱性磷酸酶(BALP)和I型氨基端延长肽(PINP)含量;Western blotting和实时荧光定量聚合酶链反应(qRT-qPCR)检测各组RANK、RANKL、OPG、磷脂酰肌醇特异性磷脂酶Cγ2(PLCγ2)、组织蛋白酶K(CTSK)、抗酒石酸酸性磷酸酶(TRAP)的蛋白和基因表达。结果核磁共振显示,模型复制成功后的小鼠左侧髋部呈高信号状态。与NC组比较,MC组BALP、PINP水平,以及OPG蛋白和基因相对表达量均降低(P<0.05),RANK、RANKL、PLCγ2、CTSK、TRAP蛋白和基因相对表达量均升高(P<0.05);与MC组比较,GBTX组和PC组BALP、PINP水平,以及OPG蛋白和基因相对表达量均升高(P<0.05),RANK、RANKL、PLCγ2、CTSK、TRAP蛋白和基因相对表达量均下降(P<0.05);与GBTX组比较,PC组OPG、RANK、RANKL、CTSK、TRAP蛋白和基因相对表达量,以及PLCγ2蛋白相对表达量差异均无统计学意义(P>0.05),而PC组PLCγ2基因相对表达量较GBTX组下降(P<0.05)。结论骨痹通消颗粒可能通过上调OPG表达,抑制RANK、RANKL、PLCγ2、CTSK和TRAP表达,从而改善股骨头坏死情况。 展开更多
关键词 激素性股骨头坏死 骨痹通消颗粒 RANKL/RANK/OPG信号轴
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肉苁蓉苷A通过JNK/MAPK通路抑制破骨细胞活性
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作者 李岳尧 张民 杨家驹 《中国组织工程研究》 CAS 北大核心 2025年第6期1144-1151,共8页
背景:研究证实肉苁蓉苷A具有抗炎、抗氧化和抗骨质疏松的作用,但其对破骨细胞分化和功能的影响及潜在的机制尚缺少研究。目的:探讨肉苁蓉苷A对核因子κB受体活化因子配体诱导的体外破骨细胞分化和骨吸收功能的影响及作用机制。方法:提... 背景:研究证实肉苁蓉苷A具有抗炎、抗氧化和抗骨质疏松的作用,但其对破骨细胞分化和功能的影响及潜在的机制尚缺少研究。目的:探讨肉苁蓉苷A对核因子κB受体活化因子配体诱导的体外破骨细胞分化和骨吸收功能的影响及作用机制。方法:提取与培养4-6周龄C57BL/6小鼠股骨和胫骨中的骨髓巨噬细胞,采用CCK-8毒性实验检验不同浓度的肉苁蓉苷A(5,10,20,40,80,160μmol/L)对骨髓巨噬细胞的毒性,抗酒石酸酸性磷酸酶染色观察不同浓度的肉苁蓉苷A干预破骨细胞的分化情况,确定药物的有效干预浓度。将实验分为阳性对照组、肉苁蓉苷A低、中、高剂量组(40,80,160μmol/L),细胞贴壁后各组均加入50 ng/mL的核因子κB受体活化因子配体诱导破骨细胞分化,肉苁蓉苷A低、中、高剂量组分别加入相应剂量的肉苁蓉苷A进行干预。采用肌动蛋白环鬼笔环肽染色和DAPI染色检测肉苁蓉苷A对破骨细胞形成的影响;骨磨片甲苯胺蓝染色观察肉苁蓉苷A对破骨细胞骨吸收功能的影响;Western blot检测JNK/MAPK通路上下游蛋白的表达情况;RT-qPCR检测抗酒石酸酸性磷酸酶、DC-STAMP、Nfatc-1、Ctsk和c-Fos等破骨细胞分化和骨吸收功能相关基因的表达情况。结果与结论:①抗酒石酸酸性磷酸酶染色、肌动蛋白环染色和骨陷窝甲苯胺蓝染色结果表明,与阳性对照组相比,肉苁蓉苷A对核因子κB受体活化因子配体诱导的体外破骨细胞的分化和骨吸收功能具有呈剂量依赖性的显著抑制作用;②RT-qPCR结果表明,与阳性对照组相比,肉苁蓉苷A高剂量组和低剂量组的抗酒石酸酸性磷酸酶、DC-STAMP、Nfatc-1、Ctsk和c-Fos等的mRNA表达量均显著降低,且肉苁蓉苷A高剂量组的降低效果更加显著;③Western blot结果显示,高剂量肉苁蓉苷A干预10,20,30和60 min时显著抑制p-JNK蛋白的表达;与阳性对照组相比,肉苁蓉苷A低、中、高剂量组显著抑制Nfatc1和c-Fos蛋白的表达,且呈剂量依赖性;④结果说明,肉苁蓉苷A能够通过降低p-JNK蛋白水平,抑制MAPK通路的激活和破骨细胞关键基因的表达,进而抑制破骨细胞的形成和骨吸收功能。 展开更多
关键词 肉苁蓉苷A 破骨细胞 MAPK JNK RANKL RANK 骨质疏松 苯乙醇苷
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miR-34a-5p、OPG、RANK、RANKL在肌少-骨质疏松症患者中的作用机制研究
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作者 杨靖元 杨物鹏 +1 位作者 刘昊 王永江 《中文科技期刊数据库(引文版)医药卫生》 2024年第10期0096-0102,共7页
探究miR-34a-5p和OPG/RANK/RANKL在肌少症及骨质疏松中的作用与机制。方法 选取80名患者分为2组,实验组44人肌少-骨质疏松症患者,对照组36人为仅患有骨质疏松症患者。检测血清OPG、RANK、RANKL表达及miR-34a基因含量,采用Excel 2019和SP... 探究miR-34a-5p和OPG/RANK/RANKL在肌少症及骨质疏松中的作用与机制。方法 选取80名患者分为2组,实验组44人肌少-骨质疏松症患者,对照组36人为仅患有骨质疏松症患者。检测血清OPG、RANK、RANKL表达及miR-34a基因含量,采用Excel 2019和SPSS 25.0软件进行数据整理和统计学分析。结果 (1)80名患者中,男性30名,女性50名,性别x2=1.458,年龄年龄x2=-1.225,骨质疏松分为骨质疏松和严重骨质疏松症,骨质疏松症患者p<0.05。(2)实验组和对照组中miR-34a均表达上调,但差异无统计学意义。(3)实验组中miR-34a与OPG、RANK、RANKL表达均有差异,与OPG成正相关,与RANKL成负相关。(4)对照组中miR-34a与OPG、RANK、RANKL表达均有差异,与OPG成正相关,与RANKL成负相关。(5)OPG在对照组中表达上调,RANKL在实验组中表达增加,RANK在两组中表达有差异。结论 (1)miR-34a可能不占主导地位,不能影响肌少症发生,但可通过OPG/RANK/RANKL信号通路影响骨质疏松症。(2)OPG/RANK/RANKL信号通路参与调节骨质疏松症及肌少症罹患过程。 展开更多
关键词 骨质疏松症 肌少症 信号通路 MICRORNA OPG RANK RANKL
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骨质疏松症的相关信号通路及其药物研究进展
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作者 胡晟 梁杰 《临床医学进展》 2024年第3期1853-1858,共6页
骨质疏松症(Osteoporosis, OP)是一种常见的老年性骨病,由于骨的形成和吸收之间的平衡被破坏导致损伤骨的微观结构,最终骨脆性增加从而造成骨折风险上升和骨折率增加。骨骼的吸收与形成与骨骼代谢的动态和平衡息息相关,可通过不同的方... 骨质疏松症(Osteoporosis, OP)是一种常见的老年性骨病,由于骨的形成和吸收之间的平衡被破坏导致损伤骨的微观结构,最终骨脆性增加从而造成骨折风险上升和骨折率增加。骨骼的吸收与形成与骨骼代谢的动态和平衡息息相关,可通过不同的方式来影响骨骼代谢的动态和平衡进而影响骨骼重建。在其涉及的机制中,骨代谢和信号通路是紧密相连的,它们都对骨质疏松症做出了重要贡献。为了进一步治疗骨质疏松症,在本文中探究了与骨代谢有关的信号通路的研究,重点是OPG/RANKL/RANK、Wnt/β-catenin和组蛋白酶K信号通路,以及相关的靶点和抗骨质疏松症药物。 展开更多
关键词 骨质疏松 OPG/RANKL/RANK WNT/Β-CATENIN 组织蛋白酶K 信号通路 骨代谢 骨质疏松症药物
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Er,Cr:YSGG激光治疗对高糖环境下微螺钉周围炎症及对RANK/RANKL信号通路的影响
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作者 刘阳 牛家慧 《口腔颌面修复学杂志》 2024年第3期170-174,共5页
目的:探讨铒铬铱钪镓石榴石(Er,Cr:YSGG)激光治疗对高糖环境下微螺钉周围炎症治疗的疗效,并分析与RANK/RANKL信号通路的关系。方法:20只正常健康雄性新西兰兔随机分为A组(微螺钉周健康组)、B组(微螺钉周围炎症组)、C组(微螺钉周围炎症... 目的:探讨铒铬铱钪镓石榴石(Er,Cr:YSGG)激光治疗对高糖环境下微螺钉周围炎症治疗的疗效,并分析与RANK/RANKL信号通路的关系。方法:20只正常健康雄性新西兰兔随机分为A组(微螺钉周健康组)、B组(微螺钉周围炎症组)、C组(微螺钉周围炎症激光治疗组),皮下注射2%四氧嘧啶建立糖尿病模型,下颌双侧无牙区植入微螺钉种植体,3个月后,A组进行菌斑控制,B组、C组用丝线拴结于微螺钉种植体颈部基台处引入炎症,C组予以Er,Cr:YSGG激光治疗。记录菌斑指数、探诊深度、牙龈指数和龈沟液量;ELISA检测龈沟液炎性细胞白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)和白细胞介素6(IL-6)水平;CBCT检查微螺钉种植体周围炎周围骨吸收状态;Western blot检测牙龈组织中核因子κB(NF-κB)/NF-κB受体性活化因子(RANK)/NF-κB受体活化因子配体(RANKL)通路相关蛋白表达。结果:CBCT检查显示与A组比较,B组微螺钉种植体周围牙槽骨有明显的炎性吸收,微螺钉种植体-骨界面愈合差,骨附着不足;与B组比较,C组一侧牙槽骨有少量新生纤维成骨。与A组比较,B组PI、PD、GI水平较高,龈沟液量较多,龈沟液中IL-1β、TNF-α和IL-6水平较高,牙龈中NF-κBp65、RANK、RANKL蛋白表达水平较高(P<0.05);与B组比较,C组PI、PD、GI水平较低,龈沟液量较少,龈沟液中IL-1β、TNF-α和IL-6水平较低,牙龈中NF-κBp65、RANK、RANKL蛋白表达水平较低(P<0.05)。结论:Er,Cr:YSGG激光治疗糖尿病兔颌骨微螺钉种植体周围炎的疗效显著,且在NF-κB/RANK/RANKL通路表达调控上可能发挥一定作用。 展开更多
关键词 铒铬铱钪镓石榴石激光 糖尿病 微螺钉周围炎 核因子κB(NF-κB)/NF-κB受体性活化因子(RANK)/NF-κB受体活化因子配体(RANKL)通路
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Low rank optimization for efficient deep learning:making a balance between compact architecture and fast training
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作者 OU Xinwei CHEN Zhangxin +1 位作者 ZHU Ce LIU Yipeng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期509-531,F0002,共24页
Deep neural networks(DNNs)have achieved great success in many data processing applications.However,high computational complexity and storage cost make deep learning difficult to be used on resource-constrained devices... Deep neural networks(DNNs)have achieved great success in many data processing applications.However,high computational complexity and storage cost make deep learning difficult to be used on resource-constrained devices,and it is not environmental-friendly with much power cost.In this paper,we focus on low-rank optimization for efficient deep learning techniques.In the space domain,DNNs are compressed by low rank approximation of the network parameters,which directly reduces the storage requirement with a smaller number of network parameters.In the time domain,the network parameters can be trained in a few subspaces,which enables efficient training for fast convergence.The model compression in the spatial domain is summarized into three categories as pre-train,pre-set,and compression-aware methods,respectively.With a series of integrable techniques discussed,such as sparse pruning,quantization,and entropy coding,we can ensemble them in an integration framework with lower computational complexity and storage.In addition to summary of recent technical advances,we have two findings for motivating future works.One is that the effective rank,derived from the Shannon entropy of the normalized singular values,outperforms other conventional sparse measures such as the?_1 norm for network compression.The other is a spatial and temporal balance for tensorized neural networks.For accelerating the training of tensorized neural networks,it is crucial to leverage redundancy for both model compression and subspace training. 展开更多
关键词 model compression subspace training effective rank low rank tensor optimization efficient deep learning
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