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Keggin type heteropolyacids-catalyzed synthesis of quinoxaline derivatives in water

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Chinese Chemical Letters 2009年第2期20卷 161-164页

作者： Tai Kun Huang Lin Shi Rui Wang xing Zhou guo xiao Xia Lu Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 PR China

Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in excellent yields in water. This method provides a new and efficient protocol in terms of small quantity of catalyst, a wide scope of substrates, and simple work-up procedure.

关键词： Keggin type heteropolyacids 1,2-Diamines 1,2-Diketones Quinoxaline derivatives Water

Comparison of white-light endoscopy,optical-enhanced and aceticacid magnifying endoscopy for detecting gastric intestinal metaplasia:A randomized trial

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World Journal of Clinical Cases 2021年第16期9卷 3895-3907页

作者： Ying-Hao Song Li-Dong Xu Meng-Xuan xing Kun-Kun Li xing-guo xiao Yong Zhang Lu Li Yan-Jing xiao Yu-Lei Qu Hui-Li Wu Xinxiang Medical University Xinxiang 453000Henan ProvinceChina Department of Gastroenterology Zhengzhou Central Hospital Affiliated to Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Pathology Zhengzhou Central Hospital Affiliated to Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Gastroenterology People's Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

BACKGROUND Gastric intestinal metaplasia(GIM)is a precancerous lesion of the stomach,which severely affects human life and ***,a variety of endoscopic techniques are used to screen/evaluate *** white-light endoscopy(WLE)and acetic-acid chromoendoscopy combined with magnifying endoscopy(MEAAC)are the interventions of choice due to their diagnostic efficacy for ***-enhanced magnifying endoscopy(ME-OE)is a new virtual chromoendoscopy technique to identify GIM,which combines bandwidth-limited light and image enhancement processing technology to enhance the detection of mucosal and vascular *** hypothesized that ME-OE is superior to WLE and MEAAC in the evaluation of *** To directly compare the diagnostic value of WLE,ME-AAC,and ME-OE for detection of *** A total of 156 patients were subjected to consecutive upper gastrointestinal endoscopy examinations using WLE,ME-AAC,and *** findings were utilized as the reference ***,sensitivity,specificity,and positive and negative predictive values of the three endoscopy methods in the diagnosis of GIM were ***,the time to diagnosis with MEAAC and ME-OE was *** experts and two non-experts evaluated the GIM images diagnosed using ME-OE,and diagnostic accuracy and intra-and inter-observer agreement were *** GIM was detected in 68 of 156 patients(43.6%).The accuracy of ME-OE was highest(91.7%),followed by ME-AAC(86.5%),while that of WLE(51.9%)was ***-site analysis showed that the overall diagnostic accuracy of ME-OE was higher than that of ME-AAC(P=0.011)and WLE(P<0.001).The average diagnosis time was lower in ME-OE than in ME-AAC(64±7 s vs 151±30 s,P<0.001).Finally,the inter-observer agreement was strong for both experts(k=0.862)and non-experts(k=0.800).The internal consistency was strong for experts(k=0.713,k=0.724)and moderate for non-experts(k=0.667,k=0.598).CONCLUSION For endoscopists,especially experi

关键词： Magnifying endoscopy Optical-enhanced Acetic-acid Gastric intestinal metaplasia

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： Yiyang Qin Wenzhen Zhu Tingting guo Yiran Zhang Tingting xing Peng Yin Shihua Li xiao-Jiang Li Su Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor

南黄海北部盆地中、新生代构造热演化史模拟研究

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地球物理学报 2017年第8期60卷 3177-3190页

作者：庞玉茂张训华郭兴伟肖国林朱晓青中国科学院海洋研究所青岛266071 中国科学院大学北京100049 海洋国家实验室海洋矿产资源评价与探测技术功能实验室青岛266071 山东省沉积成矿作用与沉积矿产重点实验室山东科技大学青岛266590 国土部海洋油气资源与环境地质重点实验室青岛海洋地质研究所青岛266071

盆地深部地球动力学过程控制和影响着浅部的构造热演化过程,针对南黄海北部中、新生界断陷盆地,将地球动力学模拟技术与传统古温标法相结合,对研究区中、新生代伸展断陷期演化以来的构造热演化史进行了研究.对基于改进McKenzie模型的数... 详细信息

盆地深部地球动力学过程控制和影响着浅部的构造热演化过程,针对南黄海北部中、新生界断陷盆地,将地球动力学模拟技术与传统古温标法相结合,对研究区中、新生代伸展断陷期演化以来的构造热演化史进行了研究.对基于改进McKenzie模型的数值模拟的原理、方法和过程进行了探讨,包括理论与计算构造沉降趋势拟合、伸展系数计算与误差校正、模拟参数定义及一维模拟结果的三维初步应用等方面.研究表明,南黄海北部盆地中生代以来伴随裂陷拉张过程其古热流整体呈现升高趋势,至晚白垩世末到古新世期间最高可达80 mW·m^(-2),古地温梯度最高可达49℃/km,部分单井构造沉降史模拟结果显示多期拉张特征,裂后期热流持续降低,至渐新世末到中新世热流约为65 mW·m^(-2),与现今热流值相当.利用一维数值模拟获取的相应参数及热史恢复结果,对盆地的古地温场进行了三维模拟恢复,取得了较好的应用效果,研究方法和成果对于盆地构造演化、油气资源评价及成藏模拟等均有重要意义.

关键词：南黄海盆地构造沉降构造热演化史地温场数值模拟

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干旱荒漠区天然砂砾路基填料压实特性分析

中国公路学报 2017年第2期30卷 18-24页

作者：包卫星郭小龙杨万精交通运输部公路科学研究院北京100088 清华大学土木工程系北京100083 新疆交通建设管理局新疆乌鲁木齐830049 北京交通大学土木建筑工程学院北京100044 西安市城乡建设委员会陕西西安710003

为研究天然砂砾路基填料的振动压实特性,首先采用筛分法对干旱荒漠地区多条在建高速公路的天然砂砾路基填料进行颗粒组成分析,其次进行表面振动压实试验,采用湿土法分析含水量对天然砂砾干密度的影响,采用干土法分析含石量、级配特性和... 详细信息

为研究天然砂砾路基填料的振动压实特性,首先采用筛分法对干旱荒漠地区多条在建高速公路的天然砂砾路基填料进行颗粒组成分析,其次进行表面振动压实试验,采用湿土法分析含水量对天然砂砾干密度的影响,采用干土法分析含石量、级配特性和振动时间对天然砂砾压实效果的影响。基于不同粗颗粒组含量下的最大干密度结果,拟合了天然砂砾最大干密度与粗颗粒中各粒组含量之间的关系式,并利用粗颗粒粒组含量确定天然砂砾的最大干密度。研究结果表明:新疆干旱荒漠区天然砂砾路基填料为不均匀土,级配不良的主要原因为曲率系数较小,填料中细粒含量较少;天然砂砾的干密度随着含水量增大会有谷值与峰值,与黏性土的单峰值变化有明显区别;天然砂砾含石量对最大干密度有显著影响,其最大干密度随含石量的变化分为明显的3个阶段,当含石量为60%时,可以得到最大干密度的最大值;不同级配的天然砂砾的干密度对振动时间的敏感性有明显区别。

关键词：道路工程压实特性振动压实天然砂砾含石量最大干密度

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政府公司——我国PPP项目理想模式之证成

税务与经济 2017年第3期 18-23页

作者：邢栋郭晓珍吉林大学法学院吉林长春130012 厦门理工学院经济管理学院福建厦门361024

近年来,PPP项目在我国发展迅速,已经作为一种重要的公共产品提供方式在全国各地推广。但在其迅速发展的同时,如何为之选择科学有效的载体并依法运行,成为学界探索的热点。源自美国的政府公司,以其灵活的机制、科学的授权、公平的分配、... 详细信息

近年来,PPP项目在我国发展迅速,已经作为一种重要的公共产品提供方式在全国各地推广。但在其迅速发展的同时,如何为之选择科学有效的载体并依法运行,成为学界探索的热点。源自美国的政府公司,以其灵活的机制、科学的授权、公平的分配、适度的监管等特征,应该成为我国PPP项目建设的良好载体的选择之一。因此,在法律保障层面,应在立法、执法、司法等方面为政府公司这一模式进入PPP创造条件。在赋权与控权相结合的权利和权力博弈中,实现项目的健康发展。

关键词： PPP项目政府公司公法人公共产品

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数据库系统的优化并行控制算法

计算机科学 2003年第10期30卷 172-174页

作者：赵若韵黄国兴肖晶华东师范大学计算机科学技术系上海200062

1.引言所谓事务就是可以保持数据库一致性的任何原子操作序列.操作可以是对数据库实体的读或写.为了一组事务可以同时执行,要引入并行控制机制[3],以保证多个事务对数据库操作后,数据库仍保持一致性.

关键词：数据库系统优化并行控制算法数据对象事务处理

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新形势下农村贿选的成因与治理措施

山西大同大学学报（社会科学版） 2016年第4期30卷 6-9页

作者：邢叶荣郭晓刚山西大同大学政法学院山西大同037009

我国实践了将近30年的全国范围内的农村基层选举,民主选举取得了一定成绩,但近年来,村委会选举中出现了严重的"贿选"现象是个不争的事实。农村贿选问题必须放置在取消农业税、粮食直补、建设新农村、发展城镇化等一系列国家政策的新形... 详细信息

我国实践了将近30年的全国范围内的农村基层选举,民主选举取得了一定成绩,但近年来,村委会选举中出现了严重的"贿选"现象是个不争的事实。农村贿选问题必须放置在取消农业税、粮食直补、建设新农村、发展城镇化等一系列国家政策的新形势下加以分析。村庄人口规模和人口流动、姓氏家族力量、村庄经济和区位优劣、村庄经济政治分层、乡镇干部权力寻租等诸因素影响农村的基层选举。因此,提出相应治理贿选的措施,以有效预防和遏止农村贿选。

关键词：村委会选举贿选治理措施

Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang Ye Haoxi Chai Yujia Jiang Teng Wang Xia Ran Qimin Xia Ziye Xu Yuting Fu guodong Zhang Hanyu Wu guoji guo Hongshan guo Yijun Ruan Yongcheng Wang Dong xing Xun Xu Zemin Zhang Beijing Advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research Bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for Advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University Department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. Furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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