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991.
Xiao ZQ Chen Y Yi B Li MY Zhang PF Yi H Duan CJ Li C Li JL Tang CE Yang F Zhu GQ Chen ZC 《Proteomics. Clinical applications》2007,1(7):688-698
A proteomics-based approach has been used to identify proteins that commonly elicit a humoral immune response in nasopharyngeal carcinoma (NPC). Sera from 19 newly diagnosed NPC patients and 19 healthy individuals were analyzed for IgG autoantibodies against NPC proteins resolved by 2-DE. Protein spots that exhibited selective reactivity with sera from NPC patients were identified by MS. Among nine identified proteins, cytokeratin 19 (CK19), Erb3 binding protein (EBP1), and Rho GDP dissociation inhibitor-beta (Rho-GDI-2) induced autoantibodies in more than 36.8% of NPC patients but not in healthy individuals. Furthermore, Western blot analysis and immunohistochemical staining were performed to determine the expression and localization of CK19, EBP1, and Rho-GDI-2 in NPC and normal nasopharyngeal mucosal tissues. Up-regulated CK19 and EBP1, but not Rho-GDI-2, were observed in NPC vs. normal tissue. Subcellular localization of the three proteins in NPC tissue was same as that in the normal tissue. Thus, overexpression of CK19 and EBP1 may be one of the mechanisms for their autoantibody development in NPC. To validate the findings of a proteomic analysis, occurrence of autoantibodies against these three proteins was detected by immunoprecipitation and Western blot analysis in additional 30 NPC patients, 23 other types of cancer patients and 20 healthy individuals. Results showed that frequency of autoantibodies against CK19, EBP1 and Rho-GDI-2 in NPC patients was significantly higher than that in other types of cancer patients and healthy individuals. We conclude that CK19, EBP1 and Rho-GDI-2 may have utility in NPC screening and diagnosis. 相似文献
992.
TCP/IP协议问题透析 总被引:5,自引:0,他引:5
针对TCP/IP在无线和安全领域的应用展开论述,详细分析了TCP/IP在几个关键的地方存在的问题,并分别就慢速启动算法、初始窗口大小、初始窗口增加策略、RTO估计器、延迟响应、内核实现的不足和安全漏洞进行了研究,给出了一些建设性的解决办法,为今后的进一步研究奠定了基础。 相似文献
993.
994.
利用演化神经网络研究有机污染物色谱保留值 总被引:1,自引:1,他引:0
利用分子连接性指数作为分子的描述性参数,定量刻画两类主要环境污染物的分子结构,通过演化神经网络分别建立了多环芳烃(PAH)和酚两类有机污染物的结构与色谱保留值之间的定量关系。计算过程中,采用留十法(Ieave-10-out)对所有化合物进行了计算,并将计算值与实验值进行了比较。 相似文献
995.
996.
由于Web Services原有的消息寻址规范WSRouting存在安全隐患,W3C制定了WSAddressing规范,用于替代WSRouting。提出一种基于WSAddressing规范的解决方案,使用一致的寻址模式发送事件消息来实现消息级的安全,提高异构系统集成的安全性。 相似文献
997.
998.
999.
Ji Feng Zhang Le Yi Wang 《Automatic Control, IEEE Transactions on》2001,46(7):1137-1141
The fundamental issues of capability of robust and adaptive control in dealing with uncertainty are investigated in stochastic systems. It is revealed that to capture the intrinsic limitations of adaptive control, it is necessary to use supt types of transient and persistent performance, rather than lim supt types which reflect only asymptotic behavior of a system. For clarity and technical tractability, a simple first-order linear time-varying system is employed as a vehicle to explore performance lower bounds of robust and adaptive control. Optimal performances of nominal, robust and adaptive control are explicitly derived and their implications are discussed in an information framework. An adaptive strategy is scrutinized for its achievable performance bounds. The results indicate that intimate interaction and inherent conflict between identification and control result in a certain performance lower bound which does not approach the nominal performance even when the system varies very slowly. Explicit lower bounds are obtained when disturbances are either normally or uniformly distributed 相似文献
1000.