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基础设施是一国经济发展的基础,是发挥社会经济各个部门各项功能所必不可少的基本条件,往往需要大额、长期的资金投入.项目融资作为国际金融的一个重要分支,近30年来已经发展成为一种为大型工程项目建设开发筹集资金的卓有成效并且日趋成熟的手段.在20世纪80年代中期,项目融资被介绍到了我国,并且在一些大型的国内和国外的投资项目中得到了成功的运用.对我国基础设施项目融资结构的形成原因进行了分析,结合对中国基础设施融资环境的分析,对我国基础设施融资体制提出建议方案. 相似文献
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MG DeCastro GA Denys LL Fauerbach JK Ferranti K Hawkins LC Masters D Rimland RJ Sharbaugh J Zeller 《Canadian Metallurgical Quarterly》1999,27(1):54-55
The Association for Professionals in Infection Control and Epidemiology, Inc (APIC), is a multidisciplinary, voluntary, international organization of professionals who practice infection control and the application of epidemiology in all health settings. APIC is an international leader in prevention and control of infection transmission. 相似文献
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Transformants of Aspergillus flavus containing the Aequorea victoria gfp gene fused to a viral promoter or the promoter region and 483 bp of the coding region of A. flavus aflR expressed green fluorescence detectable without a microscope or filters. Expression of green fluorescent protein fluorescence was correlated with resistance to aflatoxin accumulation in five corn genotypes inoculated with these transformants. 相似文献
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PT Lakkakorpi I Nakamura RM Nagy JT Parsons GA Rodan LT Duong 《Canadian Metallurgical Quarterly》1999,274(8):4900-4907
Bone resorption is initiated by osteoclast attachment to the mineralized matrix, cytoskeletal reorganization, cellular polarization, and the formation of the sealing zone. The present study examines the interaction between PYK2 and p130(Cas) (Crk-associated substrate), suggested to be part of the signaling pathway initiated by osteoclast adhesion. Using murine osteoclast-like cells (OCLs) and their mononuclear precursors (pOCs), generated in a co-culture of bone marrow and osteoblastic MB1.8 cells, we show that: 1) p130(Cas) is tyrosine-phosphorylated upon adhesion of pOCs to vitronectin or ligation of beta3 integrins; 2) p130(Cas) colocalizes with PYK2 and the cytoskeletal proteins F-actin, vinculin, and paxillin in the podosomal-rich ring-like structures of OCLs plated on glass and in the sealing zone in actively resorbing OCLs on bone; 3) p130(Cas) and PYK2 form a stable complex in pOCs, independent of tyrosine phosphorylation of either molecule, and this complex is present in Src (-/-) OCLs, in which neither protein is phosphorylated or associated with the osteoclast adhesion structure; 4) the association of p130(Cas) and PYK2 is mediated by the SH3 domain of p130(Cas) and the C-terminal domain of PYK2. These findings suggest that p130(Cas) and its association with PYK2 may play an important role in the adhesion-dependent signaling that leads to cytoskeletal reorganization and formation of the sealing zone during osteoclast activation. 相似文献
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GA Candeliere Y Rao A Floh SD Sandler JE Aubin 《Canadian Metallurgical Quarterly》1999,27(4):1079-1083
A cDNA fingerprinting strategy was developed to identify genes based on their differential expression pattern during osteoblast development. Preliminary biological and molecular staging of cDNA pools prepared by global amplification PCR allowed discrim-inating choices to be made in selection of expressed sequence tags (ESTs) to be isolated. Sequencing of selected ESTs confirmed that both known and novel genes can be isolated from any developmental stage of interest, e.g. from primitive progenitors, intermediate precursors or mature osteoblasts. EST expression provides insight into possible interrelated physiological functions and putative interacting molecules during differentiation. This method offers a functional genomics approach to isolate differentiation stage-specific genes in samples as small as a single cell. 相似文献
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