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61.
M Pan J Suárez de Lezo A Medina M Romero E Hernández J Segura F Melian F Wangüemert M Landin F Benítez M Amat F Velasco A Torres 《Canadian Metallurgical Quarterly》1997,80(10):1336-1338
Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation. 相似文献
62.
K Hashimoto M Noshiro S Ohno T Kawamoto H Satakeda Y Akagawa K Nakashima A Okimura H Ishida T Okamoto H Pan M Shen W Yan Y Kato 《Canadian Metallurgical Quarterly》1997,1355(3):303-314
Malignant human gliomas are the most common forms of primary tumors in the central nerve system. Due to their location and invasive nature, treatment so far has been mainly palliative. Thus, understanding the molecular detail of tumor transformation and progression is crucial for developing effective therapeutic strategy for this fetal tumor. Among the genetic alternations found in these tumors, p53 inactivation and PDGF/PDGFR activation represent the early events, and the loss of chromosome 10 and gene amplification and rearrangement of EGFR represent the late events. Studies with both glioma cell lines and primary tumor tissues have strongly suggested that TGF-alpha and EGFR function as an important autocrine loop in supporting proliferation of human glioma, especially in high grade glioma, since elevated TGF-alpha expression is also found in these high grade tumors. Furthermore, down regulation of the expression of TGF-alpha by antisense constructs has been shown to inhibit several types of human tumor cell growth including glioma. Other means of therapeutic approaches using this autocrine loop as a target also include the use of monoclonal antibodies and their cytotoxic conjugated. Considerable understanding of the EGFR-mediated signal transduction pathways has become available recently, which including GRB2/mSOS1 mediated MAP kinase activation; JAK/STATs pathway; PLC-gamma pathway. However, much work still needs to be done before a specific component of these pathways can be applied for effective control of tumor growth in the clinic. 相似文献
63.
The stress and velocity fields ahead of a grain-boundary crack in a material which deforms by Coble creep are investigated for a series of grain sizes using the numerical analysis technique established by Cocks [1–3]. The numerical results are compared with the linear viscous fields obtained by the boundary element method and the finite element method. It is demonstrated that a detailed knowledge of the micromechanical processes of material transport and deformation are required to determine the stress and displacement fields for the grains which immediately surround the crack tip. But the response of the surrounding material can be adequately described from a conventional linear viscous analysis of the problem. 相似文献
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65.
从理论上研究了纸张背衬不同衬底的光反射率,得出下列表达式:Rb=Ro+(R∞-Ro)×(1/R∞-Ro)/(1/B-Ro)(B为衬底的光反射率),该式简单实用且物理意义明确。利用上述公式,可将Tappi标准列出的Tappi不透明度C0.89的换算公式简化,并可从理论上定性地讨论纸张不透明度与印刷透印性的关系。 相似文献
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68.
一个实用、高效网络攻防训练模拟系统的设计与实现 总被引:1,自引:0,他引:1
随着信息技术的发展,网络安全问题日益生要,它已经渗透到国家各个领域, 并在未来信息战中扮演不可替代的角色。网络攻防是信息战不可缺少的部分,为了提高安全管理人员的素质,需要构造一个融合安全理论、实践训练于一体的安全体系,因此我们提出了建立网络攻防训练模拟系统,主要由数据库子系统、网上理论学习及考试子系统、网络攻防仿真训练子系统,成果评估子系统组成。这四部分联动融合、形成体系, 构建了以数据库子系统为基础、交互式仿真训练子系统为框架的分市式、全方位、多层次的网上学习、训练、考核体系,可实现网络攻防训练、对抗、理论学习及考核评估等功能。 相似文献
69.
Interpretation of scatterometer ocean surface wind vector EOFs over the Northwestern Pacific 总被引:1,自引:0,他引:1
Jiayi Pan Xiao-Hai Yan Quanan ZhengW.Timothy Liu Victor V Klemas 《Remote sensing of environment》2003,84(1):53-68
Satellite scatterometer winds over the northwestern Pacific were analyzed with the vector empirical orthogonal function (VEOF) method. The Hilbert-Huang transform (HHT), a newly developed non-linear and non-stationary time series data processing method, was also employed in the analysis. A combination of European Remote Sensing Satellite (ERS) −1/2 scatterometer, NASA Scatterometer (NSCAT) and NASA's Quick Scatterometer (QuikSCAT) winds covering the period from January 1992 to April 2000 and the area of 0-50°N, 100-148°E constitutes the baseline for this study. The results indicate that annual cycles dominate the two leading VEOF modes. The first VEOF shows the East Asian monsoon features and the second represents a spring-autumn oscillation. We removed the annual signal from the data set and calculated the interannual VEOFs. The first interannual VEOF represents the interannual variability existing in the spring-autumn oscillation. The temporal mode is correlated with the Southern Oscillation Index (SOI), but has a half-year lag with respect to the SOI. The spatial mode of the first interannual VEOF reflects the response of the tropical and extratropical winds to ENSO events. The second interannual VEOF is another ENSO related mode, and the temporal VEOF mode is correlated with the SOI with a correlation coefficient of 0.78, revealing the wind variability over mid-latitudes, which is associated with ENSO events. Further analysis indicated that the wind variability over the coast of East Asia represents anomalies of a Hadley cell. The quasi-biennial oscillation (QBO) was found in the temporal mode, indicating and verifying that the QBO in the wind fields is related to ENSO events. The third VEOF shows the interannaul variability in the winter-summer mode and displays the interannual variability of the East Asian monsoon. The three leading interannual VEOFs are statistically meaningful as confirmed by a significance test. 相似文献
70.
详述了国内外最新渣油催化裂化、多产柴油催化裂化、低碳烯烃催化裂化、生产清洁燃料催化裂化及催化剂的技术进展,同时根据我国实际情况对今后催化裂化技术的发展提出了建议。 相似文献