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“专精特”小巨人 1

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“专精特”小巨人企业培育路径研究——以苏南地区为例

张睿,石晓鹏,陈英武

《中国工程科学》 2017年第19卷第5期页码 97-102 doi: 10.15302/J-SSCAE-2017.05.017

摘要：

加快发展“专精特”小巨人企业是提升我国企业整体竞争力、走创新驱动与内生增长道路的重要载体和抓手，是一条符合中国实际、有利于制造业持续健康发展的必由之路，是提高全要素生产率、落实供给侧结构性改革要求的战略举措。本文对“专精特”小巨人企业的重要集聚区域——苏南地区展开专题研究，梳理省市两级政府长期以来培育小巨人企业的思路、政策和成果，为全国范围内“专精特”小巨人企业培育工作提供经验借鉴，为创新驱动和工业强基战略深入实施提供决策参考。

关键词： “专精特”小巨人工业基础政策体系

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Analyses of the seismic responses of soil layers with deep deposits

LOU Menglin, LI Yuchun, LI Nansheng

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 188-193 doi: 10.1007/s11709-007-0021-3

摘要： Several typical problems in the seismic response analysis of soil layers with deep deposits have been studied according to the seismic response analysis of the soil layer in the Shanghai region. The problems include the effect of the inclination of the bedrock under the soil layer on the seismic responses of the soil layer, the rationality of the artificial horizontal bedrock boundary in the soil layer, and the effect of the wave velocity of the bedrock and dynamic characteristics of the soil media on the seismic responses of the soil layer. Some results are obtained by numerical analysis. In the seismic response analysis, the effect of angle of inclination of the rock surface under the soil layer can be neglected if the angle is not more than two degrees. A significant error will be introduced in the calculation when the artificial horizontal rock surface is assumed in the soil layer according to the shear velocity of the soil media. The elasticity of the solid rock has little influence on the seismic response of the deep soil layer. The field investigation on the soil dynamic property should be paid more attention to.

关键词： little influence layer calculation Shanghai dynamic

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Immunohistochemical characterization of hepatic stem cell-related cells in developing human liver

XU Jun, HU Yong, WANG Jian, ZHANG Taiping, ZHOU Ji, YU Hongyu

《医学前沿（英文）》 2007年第1卷第3期页码 264-268 doi: 10.1007/s11684-007-0050-2

摘要： Little is known about the expression characteristics of the various kinds of possible markers in hepatic stem cells (HSCs) and other HSC-related cells in human fetal liver in various developmental stages. It is significant to investigate the immunohistochemical expression for better understanding of the origin, differentiation and migration of HSCs in the developing human liver. H-E staining and immunohistochemical methods were used to observe the expression of hepatic/cholangiocellular differentiation markers (AFP, GST-, CK7, CK19) and hematopoietic stem cell markers (CD34 and c-kit) in several kinds of HSC-related cells in thirty cases of fetal liver samples (4–35 weeks after pregnancy). AFP expression appears in fetal hepatocytes at four weeks’ gestation. It peaks at 16–24 weeks’ gestation and decreases gradually afterwards. Finally, weak signals were only found in some ductal plate cells and a few limiting plate cells. GST- was detected in hepatic cord cells from the sixth week and in the ductal plate cells from the eighth week. Twenty-six weeks later, only some ductal plate cells and a few limiting plate cells show positive signals. CK19 expression peaks during the 6th–11th weeks in hepatic cord cells and decreases gradually afterwards, except for the ductal plates. CK7 expression was limited in the ductal plate cells and bile ducts cells from the 14th week. CD34 and c-kit were detected at the eighth week in some ductal plate cells and a few mononuclear cells in the hepatic cords/mesenchymal tissue of portal areas. After 21 weeks, CD34 and c-kit were found only in ductal plate cells and a few mononuclear cells in the hepatic mesenchymal tissue of portal areas. Fetal hepatocytes at 4–16 weeks’ gestation are mainly constituted by HSCs characterized with bi-potential differentiation capacity. At 16 weeks’ gestation, most hepatic cord cells begin to differentiate into hepatocytes and abundant HSCs remain in ductal plate (the origin site of Hering canals). It is also indicated that the hematopoietic stem cells may give rise to some HSCs in embryonic liver. These indirectly support the hypothesis about the location and origin of HSCs in liver valley hypothesis reported previously.

关键词： origin Little mesenchymal tissue cords/mesenchymal tissue CD34