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Peptidomimetics and metalloprotease inhibitors as anticancer drugs

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Science China Chemistry 2009年第5期52卷 535-548页

作者： su li XU WenFang School of Pharmaceutical Sciences Shandong UniversityJinan 250012China

Peptidomimetics with three types, as the structural or functional mimetics of natural active peptides, can preserve the bioactivity and improve the bioavailability and the specificity towards the targets of the lead peptides. Peptidomimetics of high bioactivity can be designed through various ways including conformation restriction, modification and non-peptide design. Recently the concentration on the de-velopment of cancer chemotherapeutic drugs was transferred from cytotoxic drugs to target-based drugs, and many proteases and peptidases that play key roles in the process of tumor genesis and development was discovered, which means that peptidomimetics as potential cancer chemotherapeu-tic drugs should be paid close attention to. Our laboratory has focused on the development of small-molecule peptidomimetic inhibitors of APN, MMPs and HDACs as target-based anticancer agents. These three zinc-dependent metalloproteinases play very important roles in the process of tumor genesis, invasion, metastasis, angiogenesis and matrix degradation, so small-molecule peptidomimetic inhibitors based on them would be quite potential in the development of chemotherapeutic drugs with high selectivity.

关键词： peptidomimetics drug design metalloproteinase inhibitors anticancer agents

Reliability analysis of urban gas transmission and distribution system based on FMEA and correlation operator

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Frontiers in Energy 2014年第4期8卷 443-448页

作者： su li Weiguo ZHOU School of Mechanical Engineering Tongji University Shanghai 200092 China

In order to improve the safety management of urban gas transmission and distribution system, failure mode and effects analysis （FMEA） was used to construct the reliability analysis system of the pipeline network. To solve the problem of subjectivity and uncertainty of the multi-expert decision making, the correlation operator was introduced into the calculation of the risk priority number （RPN）. Using FMEA along with weight analysis and expert investigation approach, the FMEA evaluation table was given, including five failure modes, risk priority numbers, failure causes and effects, as well as corrective actions. The results show that correlation operator can directly process the linguistic terms and quantify the priority of the risks.

关键词： gas transmission and distribution system risk evaluation reliability analysis failure mode and effects analysis (FMEA) correlation operator

Metallogenic Correlations for the Fe-Nb-REE Mineralization in the West Mine of the Bayan Obo Deposit, Inner Mongolia, China

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 614-626页

作者： su li PENG suping China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology College of Mining and Coal Engineering Inner Mongolia University of Science and Technology

The West Mine of the Bayan Obo deposit, located in the northern-central part of Inner Mongolia, China, is enriched in Nb, rare earth elements and iron （Nb-REE-Fe） mineral resources. This paper presents a combined method to explore metallogenic correlation of the Nb-REE-Fe mineralization at the Bayan Obo West Mine. The method integrates factor analysis and Back Propagation （BP） neural network technology into processing and modeling of geological data. In this study, the Nb and REE contents of samples were transformed into discrete values to analyze the correlations among the metallogenic elements. The results show weak mineralization correlations between Nb and REEs. Nb and U are closely related in the geochemical patterns, while Fe is closely related to both Th and Mn. LREEs are an important factor for the mineralization of the Bayan Obo deposit, while Fe and Nb can be considered as the results of passive mineralization. On the basis of a metallogenic correlation analysis, the factors affecting the Fe-REE-Nb mineralization were extracted, and the Nb mineralization model was established by the BP neural network. Based on the BP neural network data computing, the variability of the Nb concentration displays a coupled multi-factor nonlinear relationship, which can be used to reveal the inherent metallogenic elemental regularities and predict the degree of element mineralization enrichment in the mining area.

关键词： Factor analysis BP neural network metallogenic correlation mineralization prediction modeling Bayan Obo deposit

Rheological Properties of Mantle Peridotites at Yushigou in the North Qilian Mountains and Their Implicationsfor Plate Dynamics

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Acta Geologica Sinica(English Edition) 1998年第2期72卷 131-141,242页

作者： SONG Shuguang su li Xi'an Institute of Geology and Mineral Resources CAGS166 East Youyi Rd.Xi'anShaanxi 710054

Abstract: This paper discusses in detail the deformation textures, glide system, petrofabrics and olivine dislocation microstructures of mantle peridotites at Yushigou in the North Qilian Mountains, northwestern China. The peridotites have undergone high-pressure, high-temperature and low-strain rate plastic flow deformation. According to the dynamic recrystallized-grain size of olivine and the average spacing between the dislocation walls as well as the chemical composition of enstatite, the authors calculated the rheological parameters of the ancient upper mantle in the study area as follows: temperatures 1025–1093°C; pressures 3043–4278 MPa; depths 95–132 km; deviatoric stress 28–32 MPa; strain rates 0.2×10?14-2.13×10?14s?1 and equivalent viscosities 0.45×1020-4.65×1020 Pa ? s. These parameters suggest that the position where plastic flow took place was correspondent to the lowvelocity zone beneath the oceanic lithosphere and that oceanization characterized by middle-velocity (1–3 cm/a) sea-floor spreading took place in the North Qilian Mountains during the Early Palaeozoic.

关键词： oceanic mantle rocks rheology sea-floor spreading North Qilian Mountains

Opportunistic spectrum sharing in software defined wireless network

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Journal of Systems Engineering and Electronics 2014年第6期25卷 934-941页

作者： Mao Yang Yong li Depeng Jin li su lieguang Zeng Department of Electronic Engineering Tsinghua University

Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network（SDWN）, and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is *** demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance.

关键词： software-defined network(SDN) wireless virtualiza-tion opportunistic spectrum sharing dynamic programming graph theory

Expression Patterns of Nine Ammonium Transporters in Rice in Response to N Status

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Pedosphere 2012年第6期22卷 860-869页

作者： li su-Mei li Bao-Zhen SHI Wei-Ming State Key Laboratory of Soil and sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Key Laboratory of Agro-ecological Processes in subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesHunan 410125(China)

Nitrogen use efficiency （NUE） was very low in China and a loss of as much as 7070 of the applied nitrogen fertilizers was reported in high-yielding rice fields. In order to investigate the molecular basis of high-affinity ammonium transport or uptake into rice （Oryza sativa L.）, we analyzed the expression profiles of nine ammonium transporters （AMT）, three each of OsAMT1, OsAMT2 and OsAMT3, at two different N requirement stages （young seedling stage and tillering stage） of rice growth as well as the changes in these expression patterns according to external N status using real-time reverse transcription polymerase chain reaction （RT-PCR）. The results suggested that the nine OsAMT genes were expressed in different organs of rice plants, including mature roots, new roots, stems, old leaves and new leaves and that the expression patterns were organ specific and independent of the positions of the corresponding proteins in the phylogenetic tree. OsAMT1;1, 3;2 and 3;3 were expressed in the roots and shoots, primarily old leaves, OsAMT1;2 and 1;3 mainly in the roots, and OsAMT2;1, 2;2, 2;3 and 3;1 mainly in the shoots, primarily in new leaves, and relatively more in the stems than other genes. The expression patterns at the two different N requirement stages were the same; however, at the tillering stage with greater N requirements, the OsAMTs transcript levels were greater than those at the young seedling stage with low N requirements. N starvation for 48 h up-regulated OsAMT1;1, 1;2, 3;1, 3;2, 3;3 and down-regulated OsAMT1;3 mRNA abundance. Following N starvation, NH4＋ and NH4NO3 re-supply down-regulated OsAMT1;2 and 3;3 and up-regulated OsAMT1;3, whereas NO3 re-supply down-regulated OsAMT1;1 and 1;2. These suggested that the organ-specific expression pattern of OsAMT could be regulated by N requirement and external N status.

关键词： external N level gene expression growth stage N requirement plant organ

Solutions and Conditional lie-Backlund Symmetries of Quasi-linear Diffusion-Reaction Equations

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Communications in Theoretical Physics 2009年第1期51卷 6-12页

作者： ZUO su-li QU Chang-Zheng Center for Nonlinear Studies Northwest University Xi＇an 710069 China Department of Mathematics Northwest University Xi＇an 710069 China

New classes of exact solutions of the quasi-linear diffusion-reaction equations are obtained by seeking for the high-order conditional lie-Baeklund symmetries of the considered equations. The method used here extends the approaches of derivative-dependent functional separation of variables and the invariant subspace. Behavior to some solutions such as blow-up and quenching is also described.

关键词： conditional lie-Backlund symmetry exact solution quasi-linear diffusion-reaction equation

The Significance of the Historical Materialist View of Labor in the New Era

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学术界 2020年第11期 210-217页

作者： su li li Guihua School of Marxism liaoning University Shenyang Liaoning 110036 School of Marxism Jilin University Changchun Jilin 130012

Labor has the core significance in the philosophy of historical *** concept of labor defines the nature of labor,affirms the decisive role of labor for human and social progress,demonstrates the form,intrinsic quality and inevitable result of labor under the capitalist economic system,and looks forward to the ultimate liberation of human beings brought by labor in Communist society in the *** whole social life of each particular era is fundamentally determined by labor,and labor is the final basis for historical materialism to divide the *** the new era of socialism with Chinese characteristics,historical materialism’s labor concept points out the fundamental way to realize individual value and all-round development,provides a reference path for the development of grassroots democracy,and guides the practice of realizing the great rejuvenation of the Chinese nation.

关键词： Labor historical materialist view of labor the New Era significance

藤黄酸下调蛋白C受体表达杀伤三阴性乳腺癌干细胞的作用机制

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中国组织工程研究 2025年第23期29卷 4888-4898页

作者：李溯王清华达梦婷杨蕊陈道桢南京医科大学附属无锡妇幼保健院优生优育医学遗传研究所江苏省无锡市214002 江南大学附属妇产医院优生优育医学遗传研究所江苏省无锡市214002 青海大学附属医院乳腺疾病诊疗中心青海省西宁市810000 青海省海东市第二人民医院院长办公室青海省海东市810600

背景:藤黄酸对乳腺癌具有很强的细胞毒性,可有效杀伤三阴性乳腺癌干细胞,但潜在的机制尚不清楚。目的:探讨藤黄酸对三阴性乳腺癌干细胞的杀伤作用及可能的机制。方法:使用PharmMapper数据库预测藤黄酸的靶点蛋白,使用String网站构建各... 详细信息

背景:藤黄酸对乳腺癌具有很强的细胞毒性,可有效杀伤三阴性乳腺癌干细胞,但潜在的机制尚不清楚。目的:探讨藤黄酸对三阴性乳腺癌干细胞的杀伤作用及可能的机制。方法:使用PharmMapper数据库预测藤黄酸的靶点蛋白,使用String网站构建各药物靶点蛋白互作网络关系,使用Cytoscape软件构建活性成分-作用靶点网络,通过R语言软件对潜在靶点进行KEGG信号通路富集分析。采用CCK-8法检测不同浓度藤黄酸对人乳腺癌细胞株MDA-MB-231活力的影响,筛选适宜的作用浓度。采用细胞球培养法富集MDA-MB-231细胞干细胞,经过不同浓度(0,0.5,1.0,2.0μmol/L)藤黄酸作用24 h,TUNEL荧光染色与流式细胞仪检测干细胞凋亡,qPCR与Western blot检测蛋白C受体表达,Western blot检测p-PI3K、p-AKT、Caspase-3和Cleaved Caspase-3蛋白表达;将干细胞分4组培养:空白对照组(干细胞不做任何处理)、siRNA-NC组、siRNA-蛋白C受体组和siRNA-蛋白C受体+PI3K激动剂组,培养36 h后,采用Western blot法检测p-PI3K、p-AKT、Caspase-3和Cleaved Caspase-3蛋白表达。结果与结论:(1)网络药理学发现,三阴性乳腺癌干细胞标志物蛋白C受体是藤黄酸的作用靶点之一;KEGG富集分析涉及细胞凋亡、上皮生长因子受体、RAS和PI3K-AKT信号通路等;(2)CCK-8检测结果显示,藤黄酸可抑制MDA-MB-231细胞活力,半数抑制浓度IC50值为(1.18±0.34)μmol/L,因此后续实验选择浓度0.5,1.0,2.0μmol/L;(3)TUNEL荧光染色和流式细胞术检测证实,藤黄酸以剂量依赖的方式诱导三阴性乳腺癌干细胞凋亡(P <0.05);qPCR和Western blot检测证实,藤黄酸可下调蛋白C受体mRNA和蛋白表达,下调Caspase-3、p-PI3K和p-AKT蛋白表达,上调Cleaved Caspase-3蛋白表达(P <0.05);siRNA-蛋白C受体转染实验也进一步证实,敲低三阴性乳腺癌干细胞蛋白C受体表达可提升Cleaved Caspase-3蛋白表达(P <0.05)、下调PI3K/AKT信号通路磷酸化水平(P <0.05),而应用PI3K激动剂740 Y-P能够降低Cleaved Caspase-3蛋白表达(P <0.05)、提升p-PI3K和p-AKT的磷酸化水平(P <0.05),一定程度上改善细胞凋亡情况;(4)结果表明,藤黄酸可能通过下调蛋白C受体来发挥三阴性乳腺癌及干细胞杀伤及诱导凋亡作用,进一步的分子机制可能和PI3K/AKT信号通路抑制有关。

关键词：三阴性乳腺癌干细胞网络药理学藤黄酸分子机制信号通路