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41.
Activation of Kupffer cells (KCs) induced that inflammatory cytokine production plays a central role in the pathogenesis of HBV infection. The previous studies from our and other laboratory demonstrated miRNAs can regulate TLR-inducing inflammatory responses to macrophage. However, the involvement of miRNAs in HBV-associated antigen-induced macrophage activation is still not thoroughly understood. Here, we evaluated the effects and mechanisms of miR-155 in HBV-associated antigen-induced macrophage activation. First, co-culture assay of HepG2 or HepG2.2.15 cells and RAW264.7 macrophages showed that HepG2.2.15 cells could significantly promote macrophages to produce inflammatory cytokines. Furthermore, we, respectively, stimulated RAW264.7 macrophages, mouse primary peritoneal macrophages, or healthy human peripheral blood monocytes with HBV-associated antigens, including HBcAg, HBeAg, and HBsAg, and found that only HBeAg could steadily enhance the production of inflammatory cytokines in these cells. Subsequently, miRNAs sequencing presented the up- or down-regulated expression of multiple miRNAs in HBeAg-stimulated RAW264.7 cells. In addition, we verified the expression of miR-155 and its precursors BIC gene with q-PCR in the system of co-culture or HBeAg-stimulated macrophages. Meanwhile, the increased miR-155 expression was positively correlation with serum ALT, AST, and HBeAg levels in AHB patients. Although MAPK, PI3K, and NF-κB signal pathways were all activated during HBeAg treatment, only PI3K and NF-κB pathways were involved in miR-155 expression induced by HBeAg stimulation. Consistently, miR-155 over-expression inhibited production of inflammatory cytokines, which could be reversed by knocking down miR-155. Moreover, we demonstrated that miR-155 regulated HBeAg-induced cytokine production by targeting BCL-6, SHIP-1, and SOCS-1. In conclusion, our data revealed that HBeAg augments the expression of miR-155 in macrophages via PI3K and NF-κB signal pathway and the increased miR-155 promotes HBeAg-induced inflammatory cytokine production by inhibiting the expression of BCL-6, SHIP-1, and SOCS-1.  相似文献   
42.
熵用于信息评价的进一步探讨   总被引:17,自引:1,他引:16  
从三个不同角度分析了信息的内在特征, 定义了信息的灵敏度、信息的价值灵敏度和信息的准确度,为不同信息的比较提供了主要的参考指标.  相似文献   
43.
基于正交试验的迷宫流道灌水器参数化设计研究   总被引:8,自引:0,他引:8  
采用正交试验设计方法,取三角形迷宫流道灌水器的关键参数为因素,利用光固化快速成形技术制作出各参数组合的灌水器与外管一体化结构原型,并进行了灌水器水力性能的试验研究.流量和流态指数的极差和方差分析结果均显示出流道转角对流态指数的影响最显著,而流道单元数对灌水器流量的影响最大,这一结果有助于解决流道经优化后带来的流量增大问题.应用多元线性回归法拟合出灌水器流量系数和流态指数与参数的关系式,进而得到了流量与压力的回归方程.验证试验结果表明,回归方程能较好地预测迷宫流道灌水器流量与压力的关系,从而实现了灌水器参数化的结构设计.  相似文献   
44.
As more strict regulations on soot emission with increasing emphasis on the emitted soot particle size have been imposed, diesel engine partially premixed combustion had been proven to achieve ultra-low NOx and soot emissions with high thermal efficiency simulta- neously, by synergy control of mixing and chemical parameters. It calls for further study in the effect of com- bustion boundaries on soot formation. In this study, soot formation characteristic was investigated by CFD code coupled with reduced n-heptane model and improved multistep soot model. History of acetylene, which is taken as the main species of PAH formation and soot surface growth, plays more important roles on soot prediction. The revised parameter of fraction of active sites αCH was introduced as the indicator of soot surface activity in diesel soot formation. The effects of combustion boundaries on soot surface activity and soot surface growth were explored in this study. When the mixture was quite homogeneous, lowered combustion temperature was the main factor for reduced soot formation due to the lowered specific surface growth rate RCH, in spite of ec/4 increasing slightly due to the slowed decay rate of surface activity. As the inhomo- geneity of the mixture was increased, more unburned hydrocarbons were produced, promoting the formation of acetylene and soot surface activity. It was the dominated reason for higher soot surface growth rate, resulted wors- ened engine-out soot. In addition, residual of CO in later combustion phase impeded the re-oxidation of soot.  相似文献   
45.
电子束熔融直接金属成型工艺的研究   总被引:1,自引:0,他引:1  
研究了工艺参数对电子束熔融工艺过程的影响,采用线性回归分析建立了一个数学模型.研究结果表明,扫描线宽与电子束电流、加速电压和扫描速度呈明显的线性关系,当搭接率为0.5时,所获得的层面质量优于搭接率小于0.5时的层面质量,回旋扫描路径可以减少热量的积累,有效地防止金属小液滴的飞溅,从而得到较好的层面质量.针对实验中出现的电子与粉末碰撞造成的未熔粉末的飞溅,采用优化的工艺参数对粉层进行预热,从而大大减少了未熔粉末的飞溅.对于扫描线的球化,采用功率与扫描速度的比值大于0.1的工艺参数进行扫描,获得了连续的扫描线.通过对工艺参数的优化,得到了性能优异的一维扫描线和二维层面,为三维实体的成型奠定了基础.  相似文献   
46.
高速动静压轴承支承主轴系统动特性测试研究   总被引:1,自引:0,他引:1  
以自行设计的高速主轴水润滑动静压轴承为基础,采用不平衡质量法识别出转子系统支撑轴承的动特性系数,通过轴承性能测试实验得到了供水压力、主轴转速等运行参数对轴承-转子系统动特性的影响.结果表明:轴承-转子系统动特性系数随系统供水压力和主轴工作转速的增加而增大;在供水压力较低时,工作转速对轴承动特性影响较小;当供水压力升高到一定程度时,工作转速对轴承的动特性产生较大影响,此项研究对轴承-转子系统结构参数的改进以及不同工况下最佳运行参数的确定具有一定的指导意义.  相似文献   
47.
风险因子的模糊综合评判法   总被引:43,自引:1,他引:42  
第一部分对风险间的关系进行了研究,归纳和定义了风险之间的五种基本关系;第二部分介绍风险因子评价法,给出了风险的模糊综合评判算法,并通过一个例子说明算法的应用.  相似文献   
48.
决策分析中一类极大熵问题的求解算法与应用   总被引:4,自引:1,他引:3  
提出了决策分析中一类极大熵问题的求解算法。与求解极大熵问题常采用的Lagrange数乘法相比, 此算法更加简便、省时, 不仅适用于决策分析, 而且对非线性规划中的基准点测试也有一定的参考价值。文章最后应用此算法对一个投资决策问题进行了求解。  相似文献   
49.
提出一种新的钢材含碳量无损检测方法,设计了可靠性材较高的检测系统,以钢材的磁特性为基础,用Autolisp语言编制计算机接口软件,测绘出钢材的磁化曲线和磁滞回线,应用神经网络理论,建立碳量和磁性特征量间的非线性映射,实现含碳量的智能化检测  相似文献   
50.
ORDERED WEIGHTED AVERAGINGAGGREGATION METHOD FOR PORTFOLIO SELECTION   总被引:1,自引:0,他引:1  
Portfolio management is a typical decision making problem under incomplete,sometimes unknown, information. This paper considers the portfolio selection problemsunder a general setting of uncertain states without probability. The investor's preferenceis based on his optimum degree about the nature, and his attitude can be described by anOrdered Weighted Averaging Aggregation function. We construct the OWA portfolio selec-tion model, which is a nonlinear programming problem. The problem can be equivalentlytransformed into a mixed integer linear programming. A numerical example is given andthe solutions imply that the investor's strategies depend not only on his optimum degreebut also on his preference weight vector. The general game-theoretical portfolio selectionmethod, max-min method and competitive ratio method axe all the special settings of thismodel.  相似文献   
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