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uPA纤溶途径与肝纤维化

世界华人消化杂志 2006年第21期14卷 2106-2111页

作者：安德明季光邢练军郑培永上海中医药大学附属龙华医院肝病研究室上海市200032

细胞外基质(extracellular matrix,ECM)过度沉积是肝纤维化的特征性表现,纤溶系统尤其是尿激酶型纤溶酶原激活剂(urokinase- plasminogen activator,uPA)所介导的纤溶途径与肝纤维化关系密切,其主要成分包括纤溶酶原、纤溶酶、纤溶酶原... 详细信息

细胞外基质(extracellular matrix,ECM)过度沉积是肝纤维化的特征性表现,纤溶系统尤其是尿激酶型纤溶酶原激活剂(urokinase- plasminogen activator,uPA)所介导的纤溶途径与肝纤维化关系密切,其主要成分包括纤溶酶原、纤溶酶、纤溶酶原激活剂及其抑制剂．uPA纤溶途径位于ECM降解酶系的顶端,肝纤维化时通过uPA-纤溶酶-基质金属蛋白酶(matrix metalloproteinases,MMPs)-ECM级联机制下调ECM降解,促进ECM在肝内沉积,而且可能在肝星状细胞(hepatic stellate cell,HSC)增殖、迁移以及肝细胞再生等过程中起到重要作用．

关键词： uPA纤溶途径肝纤维化肝星状细胞

Structural Types of Sea Embankment and Their Stability Analysis

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China Ocean Engineering 1998年第3期13卷 333-352页

作者： Mao, CX Duan, XB Mao, py Nanjing Hydraul Res Inst Dept Hydraul Engn Nanjing 210029 Peoples R China Natl Hydrol Res Inst River & Harbor Dept Nanjing 210024 Peoples R China

In this paper based on investigation on the structural types of sea embankments in the southeast coastal area of China, as well as the related tidal stages, waves and strength of marine soils, the finite element method (FEM) calculations for seepage flow stability, including the overall stability against sliding and local stability of sloping surface under the action of tidal stage and waves are carried out. A comparison of the computational results of FEM for single circular slip, composite circular slip and geogrid reinforcement against sliding shows that for calculation of stability against sliding of marine soft soil foundation it is even more reasonable to use the composite circular slip. The stability of sloping type sea embankment against sliding is slightly better than that of the vertical face type; for the combination of three defences (wave, scour and seepage defences) the sea embankment structural type of a composite cross section with a platform should be a good one, but it still should be suitable to local conditions. For the local stability of riprap slope blocks and wall face loose masonry blocks, according to the analyses of wave-induced seepage flow fields, calculating formulas are given and they are verified by model test on block stability of breakwaters.

关键词： sea embankment structural type tidal stage variation wave stroke seepage flow stability analysis

Synthesis of the Precursor of Tetrasaccharide from Laminin

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Chinese Chemical Letters 1996年第11期7卷 991-992页

作者： Zhu, XX Ding, py Cai, MS BEIJING MED UNIV SCH PHARMACEUT SCIDEPT ORGAN CHEMBEIJING 100083PEOPLES R CHINA

Synthesis of the protected tetrasaccharide II is reported as the key intermediate of tetrasaccharide from laminin that is an important glycoprotein on the basement membrane.

关键词： Synthesis of the Precursor of Tetrasaccharide from Laminin

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中国有色金属学会会刊：英文版 2001年第6期11卷 843-846页

作者： Yan, HG Chen, ZH Kang, ZT Chen, G Hunag, py Hunan Univ Sch Mat Sci & Engn Changsha 410082 Peoples R China Cent S Univ Dept Mat Sci & Engn Changsha 410083 Peoples R China

The phase formation regularities in nanometer powders of ternary alloys prepared by gas evaporation process with induction current as the heating source were investigated. Al-Cu-Mn and Al-Cu-Cr were chosen as the samples in this study. The experimental results show that the necessary conditions for forming ternary compound phases in a ternary alloy nanometer powder are that they must be able to form in a conventional bulk alloy. To obtain a ternary compound phase in nanometer powders, composition of the master alloy must be in a certain range. Changing the composition of the master alloy and evaporation temperature can control the kinds of the phases and their relative amount in the alloy nanometer powders. In present study, AlMn, Al8Mn5 and AlCu2Mn phases formed in as-prepared nanometer powders of Al-Cu-Mn alloy, and the highest relative amount of AlCu2Mn phase is about 99%. In nanometer powders of Al-Cu-Cr alloy,Cu9Al4, Al2Cu3, AlCr2 and Al13Cr2 phases formed without any ternary compound phase.

关键词： nanometer powder gas evaporation alloy powder

STUDIES ON THE TOTAL SYNTHESIS OF CIMICIFUGAMIDEFROM CIMICIFUGA DAHURICA

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Chinese Chemical Letters 1996年第6期7卷 545-548页

作者： Ding, py Zhu, XX Cai, MS Yu, DQ BEIJING MED UNIV SCH PHARMACEUT SCIDEPT ORGAN CHEMBEIJING 100083PEOPLES R CHINA CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Cimicifugamide, a new natural compound isolated from the roots of Cimicifuga dahurica, was totally synthesized by a reaction sequence of seven steps in an overall yield of 31 %. D-Galactose was used as starting material, trifluoroacetoxy was used as leaving group at C-1. The target product was characterized by IR, MS, H-1-NMR C-13-NMR and elemental analysis.

关键词： TOTAL STUDIES ON THE TOTAL SYNTHESIS OF CIMICIFUGAMIDEFROM CIMICIFUGA DAHURICA

Timing is everything:does early and late germination favor invasions by herbaceous alien plants?

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Journal of Plant Ecology 2018年第1期11卷 4-16页

作者： Margherita Gioria Petr pyšek Bruce A.Osborne Institute of Botany Department of Invasion EcologyThe Czech Academy of SciencesCZ-25243 PrůhoniceCzech Republic UCD School of Biology and Environmental Science University College DublinBelfieldDublin 4Ireland Department of Ecology Faculty of ScienceCharles University in PragueViničná7CZ-12844 Prague 2Czech Republic UCD Earth Institute University College DublinBelfieldDublin 4Ireland

Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution *** a superior competitive ability has often been proposed as a major driver of successful plant invasions,its significance depends crucially on the timing of any competitive *** assess whether a mismatch in germination phenology can favor the establishment of alien species,allowing them to exploit vacant niches where competition is *** well as having important effects on the survival,growth and fitness of a species,asymmetric competition and potential soil legacies resulting from early or late germination can also impact on species ***,early or late germination comes at a cost,increases the risks of exposure to unfavorable conditions and requires an enhanced abiotic resistance if it is to lead to successful *** Findings While there are several anecdotal accounts of early and late ger-mination for invasive species,there are limited comparative data with resident species growing under natural *** evidence from grassland communities indicates that a short-term germination advantage or priority(few days/weeks)provides inva-sive species with a strong competitive advantage over native species and is a critical factor in many *** the exploitation of periods of low competition is a plausible mechanism for the suc-cessful establishment of many invasive plants,direct evidence for this strategy is still *** is particularly true with regard to the exploitation of late germination ***,long-term comparative monitoring of the germination phenology of invasive and native plants in situ is needed to assess its significance in a range of ecosystems and its impact on community dynamics.

关键词： competition germination invasive plants phenology temporal niche

Synthesis and Crystal Structure of a Novel Complex [Ag(NIT3py)_3]·(ClO_4)(H_2O)

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Chinese Journal of Structural Chemistry 2005年第6期24卷 625-628页

作者： ZHANGChen-Xia LIAODai-zheng JIANGZong-Hui YANShi-Ping SchoolofMaterialsScienceandEngineering TianjinUniversityTianjin300072China／／DepartmentofChemistryNankaiUniversityTianjin300071China DepartmentofChemistry NankaiUniversityTianjin300071China DepartmentofChemistry NankaiUniversityTianjin300071China／／StateKeyLaboratoryofCoordinationChemistryNanjing210093China

A novel complex [Ag(NIT3py)3]?(ClO4)(H2O) has been synthesized and structurally characterized by X-ray diffraction method. It crystallizes in the rhombohedral system, space group R 3 with a = 15.8227(17), b = 15.8227(17), c = 31.445(3) ?, γ = 120°, V = 6817.8(12) ?3, Dc = 1.370 g/cm3, Z = 6, μ = 0.566 mm-1, Mr = 937.18, F(000) = 2916, R = 0.0715, wR = 0.2115 and GOF = 1.086. The structure consists of Ag(NIT3py)3+ cation moiety, one water molecule and one perchloric ion. The Ag(I) ion is in a trigonal planar coordination environment formed by three nitrogen atoms from three NIT3py ligand molecules.

关键词： crystal structure nitronyl nitroxide radical Ag(I) complex magnetism ferromagnetic interactions

Successful conservative management of Class III iatrogenic aortic dissection

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Journal of Geriatric Cardiology 2018年第3期15卷 235-237页

作者： Wai Kin Chi Gary Tse Bryan py Yan Department of Medicine and Therapeutics Faculty of Medicine The Chinese University of Hong Kong Hong Kong China Division of Cardiology Prince of Wales Hospital Shatin Hong Kong China Li Ka Shing Institute of Health Sciences Faculty of Medicine The Chinese University of Hong Kong Hong Kong China

Iatrogenic aortic dissection （IAD） is a rare complication of percutaneous coronary intervention （PCI） with an estimated incidence of 0.02%--0.04%. lAD occurs more frequently in the setting of urgent PCI for acute myocardial infarction （AMI）（0.19%） than for elective procedures （0.01%）.[11 The mortality risk associated with IAD is high （16%） and is comparable to that for spontaneous aortic dissection （16%）.Urgent surgery is the treatment of choice for extensive dissection or hemodynamic instability. In this report, we present a case of severe IAD that was managed conservatively with good clinical outcome.

关键词： Conservative management Iatrogenic aortic dissection Percutaneous coronary intervention

First Total Synthesis of Four Benzodioxane Neolignans

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Chinese Chemical Letters 2000年第10期11卷 875-878页

作者： Jing, XB Gu, WX Bie, py Ren, XF Pan, XF Lanzhou Univ Dept Chem Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Four 1,4-benzodioxane neolignans were first synthesized from pyrogallol, in which the Claisen rearrangement was used to afford three important C-6-C-3 units.

关键词： synthesis neolignans Eusiderin K Eusiderin J Eusiderin E Eusiderin F