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World Journal of Gastrointestinal Oncology 2017年第4期9卷 153-159页

作者： Zheng-Yun Liang Xing Kang hong Chen meng Wang Wen-xian Guan Department of General Surgery Qianxinan People’s Hospital Department of General Surgery Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical School

AIM To investigate the effects of Clostridium perfringens enterotoxin(CPE) on gastric cancer cells which highly expressed claudin-4(CL4) *** In this study, we detected expression of CL4 protein in different gastric cancer cell lines. Then, we investigated the effects of CPE on SGC7901 cells which highly expressed CL4 protein and the effects of CPE on sub-cutaneous tumor in nude mice *** CL4 are highly expressed in SGC7901 cells. CPE expressedsignificant cytotoxicity in SGC7901 cells. Suppression of CL4 expression significantly decreased CPE-mediated cytotoxicity. CPE also inhibited tumor growth in subcutaneous tumor xenograft *** CPE showed CL4 mediated cytotoxicity on gastric cancer cells SGC7901 and inhib-ited tumor growth in nude mice models.

关键词： Gastric cancer Clostridium perfringens enterotoxin Claudin-4 protein Cytotoxicity Tight junction

Synthesis of Terpyridine Derivatives Containing β-Cyclodextrin

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Chinese Chemical Letters 2003年第5期14卷 445-447页

作者： xian hong YIN Department of Chemistry Guangxi University for NationalitiesNanning 530006

A novel b-cyclodextrin-based terpyridine derivatives has been prepared by the coupling of 4-(4-bromomethyl phenyl)- 2, 2:6, 2-terpyridine with mono-6-hydroxy permethylated b- cyclodextrin. The cyclodextrin dimmer appending a 4-phenyl-2,2:6,2- terpyridine spacer on the primary faces was synthesized by reaction of 4-phenyl-2,2:6,2-terpyridine-6,6-dicarbonitrile with an excess of 6-deoxy-6-O-tosyl-b-cyclodextrin.

关键词： Cyclodextrin terpyridine synthesis.

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自激式电感耦合等离子体光源设计及光谱分析

光谱学与光谱分析 2025年第1期45卷 66-71页

作者：卢思贤龙开红詹陈锐李明北方工业大学电气与控制工程学院北京100144 益阳职业技术学院电子与信息工程学院湖南益阳413055

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电... 详细信息

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电路复杂、体积庞大、阻抗匹配速度较慢、最大输出功率有限。设计了一种基于镀金工艺的高功率MOSFET和变频实现阻抗匹配的自激式ICP光源,该光源采用射频放大和阻抗匹配一体化的设计,把从负载线圈采样的频率信号f_(1)以及功率放大电路放大后的频率相位f_(0)进行相位比较,再根据两者相位差的变化,进而控制频率的变化,实现阻抗匹配;设计上采用了镀金工艺的金属化硅N通道型高功率的MOSFET实现功率放大,具有更大的功率密度、更小的体积,最大输出功率超过2400 W。对研制的ICP光源进行了电学静态测试,给出了鉴相器、压控振荡器以及功率的输出特性,验证了各电路在相应工作状态下的性能表现;同时结合光谱仪进行了包含Ba、Na和Li元素标准溶液的测试,获得了目标元素的光谱信号;另外,对获得的光谱信号进行了处理,使用了基于EEMD特征增强的方法对目标元素光谱信号进行有效增强,信号的线性决定系数(R^(2))从0.97降至0.99,相对标准偏差(RSD)从6.47%降至1.07%,增强了信号的准确性和可用性。本文所研制的自激式ICP光源,通过射频放大和阻抗匹配一体化设计缩小了体积,变频技术使阻抗匹配速度从毫秒级提升到纳秒级,镀金工艺的MOSFET技术使最大输出功率从原来的1800 W增加到2400 W,为ICP光源的进一步优化和应用奠定了基础,具有重要的科学研究和工程实践意义。

关键词：自激式ICP光源阻抗匹配光谱信号 EEMD算法

Synthesis and application of chiral N,N'-dialkylated cyclohexanediamine for asymmetric hydrogenation of aryl ketones

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Chinese Chemical Letters 2011年第2期22卷 155-158页

作者： meng Lin Ma Chuan hong Ren Ya Jing Lv Hua Chen xian Jun Li Department of Chemistry Xihua UniversityChengdu 610039China Key Lab of Green Chemistry and Technology Ministry of EducationThe Institute of Homogeneous Catalysis Faculty of ChemistrySichuan UniversityChengdu 610064China

Chiral N,N＇-dialkylated cyclohexanediamine derived ligands have been synthesized and used in the asymmetric hydrogenation of aryl *** active alcohols with up to 90%enantiomeric excess were obtained in high yields.

关键词： Chiral diamine Aryl ketone Asymmetric hydrogenation Ruthenium complex

The maximal Lyapunov exponent of a co-dimension two-bifurcation system excited by a bounded noise

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Acta Mechanica Sinica 2012年第2期28卷 511-519页

作者： Sheng-hong Li xian-Bin Liu State Key Lab of Mechanics and Control for Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics210014 NanjingChina School of Mathematics and Physics Jiangsu University of Science and Technology212003 ZhenjiangChina

In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise. By using a perturbation method, the expressions of the invari- ant measure of a one-dimensional phase diffusion process are obtained for three cases, in which different forms of the matrix B, that is included in the noise excitation term, are assumed and then, as a result, all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed. Via Monte-Carlo simulation, we find that the an- alytical expressions of the invariant measures meet well the numerical ones. And furthermore, the P-bifurcation behav- iors are investigated for the one-dimensional phase diffusion process. Finally, for the three cases of singular botmdaries for one-dimensional phase diffusion process, analytical ex- pressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system.

关键词： Maximal Lyapunov exponent Perturbationmethod. Bounded noise. Diffusion process

Synergistic Effects of Activin A and Fibroblast Growth Factor 2 in the Modulation of Insulin Expression

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Chemical Research in Chinese Universities 2006年第2期22卷 229-232页

作者： BAO Yong-li JIANG hong-yu Ji Shou-xian WU Yin meng xiang-ying LI Yu-xin Institute of Genetics and Cytology Northeast Normal University Changchun 130024 P. R. China The First Affiliated Hospital Jilin University Changchun 130021 P. R. China The Second Affiliated Hospital Jilin University Changchun 130041 P. R. China

Diabetes is the most prevalent and serious metabolic disease, and the number of diabetic patients worldwide is increasing. The reduction of insulin biosynthes is in pancreatic E-cells is closely associated with the onset and progression of diabetes, therefore, it is important to search for ways to induce insulin-producing cells in non-E-cells. In the present study, it has been reported that activin A and a basic fibroblast growth factor 2 （ FGF2）, can synergistically increase the insulin mRNA level, in both mouse El4 striatal primary cell cultures and the hippocampal neuronal cell line HT22. Activin A and FGF2 can jointly stimulate the nuclear translocation of Smad3 and specifically activate ERK1/2. It is interesting to note that a specific inhibitor for MEK, U0126, can efficiently block the induction of an insulin promoter activity by activin A and FGF2. This indicates that activin A collaborates with FGF2, giving a signal to induce the insulin gene through selective activation of the ERK-type MAP kinase and Smad3 in mouse striatal and HT22 cells. These data suggest that activin A may act in concert with FGF2 for the development of insulin -positive neurons

关键词： Activin A Fibroblast growth factor 2 (FGF2) Insulin

NDUFA8 potentially rescues Wolbachia-induced cytoplasmic incompatibility in Laodelphax striatellus

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Insect Science 2023年第6期30卷 1689-1700页

作者： Jie Chen meng-Ke Wang Qi-xian Xie Xiao-Li Bing Tong-Pu Li Xiao-Yue hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

The endosymbiont Wolbachia manipulates host reproduction by several strategies, one of the most important of which is cytoplasmic incompatibility (CI). CI can be rescued when Wolbachia-infected males mate with females infected with the same Wolbachia strain. However, the potential rescue mechanism of CI in the small brown planthopper Laodelphax striatellus is unclear. In this study, comparative transcriptome analysis was applied to explore the effect of Wolbachia on L. striatellus eggs. A total of 1387 differentially expressed genes were identified. RNA interference of 7 Wolbachia-upregulated key planthopper genes reduced egg reproduction, suggesting that Wolbachia might improve fecundity in L. striatellus by affecting these 7 genes. Suppressing the expression of another upregulated gene, NDUFA8 (encoding NADH dehydrogenase [ubiquinone] 1 α subcomplex subunit 8-like) by RNA interference significantly increased the mortality of early embryos without affecting the number of deposited eggs. Wolbachia infection upregulated the mRNA level of NDUFA8, and dsNDUFA8 treatment of Wolbachia-infected females recreated CI-like symptoms, suggesting that NDUFA8 is associated with the rescue phenotype. Because all L. striatellus populations worldwide are infected with Wolbachia, NDUFA8 is a potential pest control target.

关键词： cytoplasmic incompatibility Laodelphax striatellus NDUFA8 reproduc-tion rescue Wolbachia

联合FOD-sCARS的土壤有机质高光谱机器学习估测模型

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光谱学与光谱分析 2025年第1期45卷 204-212页

作者：吴梦红窦森林楠姜然哲陈思李佳璇付佳伟梅显军吉林农业大学资源与环境学院吉林长春130118 吉林建筑大学测绘与勘查工程学院吉林长春130118 吉林大学生物与农业工程学院吉林长春130115

土壤有机质(SOM)含量是表征土壤质量的关键指标,在全球碳循环系统中发挥重大作用。快速准确的SOM估算和空间制图对土壤碳库估算、作物生长监测和耕地规划管理具有重要意义。利用传统方法监测区域性SOM含量耗时费力,基于高光谱遥感影像建... 详细信息

土壤有机质(SOM)含量是表征土壤质量的关键指标,在全球碳循环系统中发挥重大作用。快速准确的SOM估算和空间制图对土壤碳库估算、作物生长监测和耕地规划管理具有重要意义。利用传统方法监测区域性SOM含量耗时费力,基于高光谱遥感影像建立SOM估测模型是现在较为合理有效的方法。为探索解决目前高光谱遥感影像建立SOM含量估测模型存在光谱数据冗余、光谱数据特征提取精度低、小样本模型泛化能力不强的问题,选择位于青海省湟中县的研究区,共采集67个土壤样本。获取资源1号02D(ZY1-02D)高光谱遥感影像并进行预处理得到样点像元光谱数据,采用分数阶微分变换(FOD)方法挖掘与SOM含量具有响应关系的敏感波段,以0.2为一个步长,利用相关性阈值法对比分析不同阶次微分处理数据挖掘能力;运用稳定性竞争性自适应重加权采样算法(sCARS)去除高光谱冗余数据获取建模特征波段,选择随机森林(RF)、极端梯度提升树、极限学习机和岭回归机器学习作为建模算法,以全波段和特征波段光谱数据分别作为模型输入变量构建SOM估测模型进行高光谱反演研究工作;最后根据最优特征变量和建模算法,基于ZY1-02D遥感影像进行了SOM空间分布制图。结果表明:采用FOD变换相比整数阶可以大大提高波段与SOM含量间的相关性,挖掘出更多细微的与SOM含量产生响应关系的光谱波段,其中0.8阶微分变换效果最优,较原始波段相比相关系数最大值提高了0.546;相较于全波段光谱数据,采用sCARS特征提取方法获取特征波段构建模型的估测精度得到较大提升,说明sCARS可以有效提升建模数据的质量,提升模型预测精度。建模算法中RF表现最优,R_(p)^(2)(模型决定系数)达到0.766,RPD达到1.86,较全波段建模结果R_(p)^(2)提升约7.58%;基于FOD-sCARS和RF实现了区域SOM含量估测制图。研究进一步验证利用星载高光谱遥感影像是实现区域SOM估测制图的可靠途径,研究结果可为估测区域SOM含量提供新思路,为利用星载高光谱遥感影像绘制SOM含量空间分布图提供了数据支持。

关键词：高光谱遥感影像分数阶微分变换稳定性竞争性自适应重加权采样算法土壤有机质随机森林

Real-time monitoring of DNAzyme cleavage process using fluorescent assay

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Chinese Chemical Letters 2009年第8期20卷 990-994页

作者： xiang xian meng Xiao Hai Yang Ke Min Wang Wei hong Tan Qiu Ping Guo State Key Laboratory of Chemo/Biosensing and Chemometrics Engineering Center for BiomedicineKey Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan ProvinceCollege of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

Detection of deoxyribozyme （DNAzyme） cleavage process usually needs complex and time-consuming radial labeling, gel electrophoresis and autoradiography. This paper reported an approach to detect DNAzyme cleavage process in real time using a fluorescence probe. The probe was employed as DNAzyme substrate to convert directly the cleavage information into fluorescence signal in real time. Compared with traditional approach, this non-isotope method not only brought a convenient means to monitor the DNAzyme cleavage reaction, but also offered abundant dynamic data for choosing potential gene therapeutic agents. It provides a new tool for DNAzyme research, as well as a new insight into research on human disease diagnosis. Based on this method, 8- 17deoxyribozyme （8-17DNAzyme） against hepatitis C virus RNA （HCV-RNA） was designed and the cleavage process was studied in real time. ？2009 Ke Min Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： DNAzyme Cleavage Real time HCV-RNA

Effect of Si addition on microstructure and mechanical properties of Al-Mg-Si-Zn alloy

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China Foundry 2020年第1期17卷 15-20页

作者： Fan-bo meng hong-jun Huang Xiao-guang Yuan Ze-wen Cui xian-lei Hu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China School of Materials Science and Engineering Liaoning Technology UniversityFuxin 123000China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004China

The effect of Si addition on the microstructure and mechanical properties of Al-Mg-Si-Zn aluminum alloys were *** show that the microstructure of Al-Mg-Si-Zn alloy with low Si contents is mainly composed of Mg2Si and Mg5Si6 *** the increasing of Si content,Si and Al3.21Si0.47 phases precipitate in the form of eutectic phases in the alloys,at the same time,the mean shape factor of the second phase firstly increases and then *** analysis results show that the Si content has the main influence and the mean shape factor has the least influence on tensile *** strength increases significantly with the addition of Si,however,there is a remarkable drop in the elongation of the *** elongation is related to the formation of monotonous Al(200)structure and the enlargement of interplanar spacing of(111)and(200)crystalline planes.

关键词： Si content mean shape factor area fraction tensile strength aluminum alloy