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1.
Objective To investigate the change of protein expression of lung tissue of rabbit after ischemic preconditioning (IP) and try to elucidate the potential protective mechanism of IP. Methods 12 domestic rabbits were randomly divided into group IP and group control (6 rabbits in each group). All the left lungs were afflicted by ische mia-reperfusion injury except that those in group IP were subject to IP prior to ischemic phase. 2-DE was employed to separate the total protein of the lung tissue. PDQuest analysis software was used to distinguish the differently expressed protein spot. MALDI-TOF-MS and Mascot database searching were exploited to identify these proteins. Results 1) IP attenuated the ischemia-reperfusion lung injury. 2) The proteomic analysis showed 35 target proteins, of which 17 were characterized such as phosphatidylinositol 3-kinase(PI3k) delta catalytic subunit. Conclusions 1) Proteomic is a promising tool to investigate the IP and ischemia-reperfusion lung injury. 2) That IP inhibits inflammatory cascades through phosphatidylinositol 3-kinase signal transduction pathway may be one of its protective mechanism. Foundation item: Project(2004036433) supported by the Postdoctoral Science Foundation of China; project(B2004024) supported by the Science Foundation of Public Health Bureau of Hunan Province  相似文献   
2.
Effects of outcome-alone pretraining and posttraining exposure were investigated in conditioned suppression experiments conducted within a sensory preconditioning preparation with rats. Experiment 1 found that interference by outcome postexposure was stronger than that by outcome preexposure, suggesting a recency effect. Experiment 2 found that after a long retention interval, outcome preexposure produced more interference than outcome postexposure, suggesting a shift from recency to primacy with increasing retention interval. Experiment 3 showed that presentation of a priming stimulus that had been embedded within the earlier phase of treatment also caused a shift from recency to primacy. These results suggest that, at least in a sensory preconditioning paradigm, retrievability of outcome-alone exposure memory is an important determinant of any outcome-alone exposure effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
A new class of normalized approximate inverse matrix techniques, based on the concept of sparse normalized approximate factorization procedures are introduced for solving sparse linear systems derived from the finite difference discretization of partial differential equations. Normalized explicit preconditioned conjugate gradient type methods in conjunction with normalized approximate inverse matrix techniques are presented for the efficient solution of sparse linear systems. Theoretical results on the rate of convergence of the normalized explicit preconditioned conjugate gradient scheme and estimates of the required computational work are presented. Application of the new proposed methods on two dimensional initial/boundary value problems is discussed and numerical results are given. The parallel and systolic implementation of the dominant computational part is also investigated.  相似文献   
4.
Preconditioning methods based on Calderon's formulae for the periodic fast multipole method for elastodynamics in 3D are investigated. Three different types of formulations are proposed. The first type is a preconditioning just by appropriately ordering the coefficient matrix without multiplying preconditioners. The other two types utilise preconditioners constructed using matrices needed in the main fast multipole method algorithms. We make several numerical experiments with proposed preconditioners to confirm the efficiency of these proposed methods. We also conclude that the preconditioning of the first type is faster with respect to the computational time than other preconditioning methods discussed in this article. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
5.
There are many situations in engineering where we need to calculate the eigensystem of a matrix A which is given as a product of matrices, that is, A = A 1 A 2···A p . Since, usually, we first perform the multiplication of the factors, the matrix A often becomes very ill-conditioned. Actually this happens even when A is a symmetric matrix, which will be our concern here. In this article we introduce a new approach to calculate the eigensystem of A without performing the indicated multiplication, or performing only partially the multiplication of the factors.  相似文献   
6.
燃煤电厂在推广"超低排放"CEMS气态污染物监测系统监测低量程SO2和NOx中,低温、高湿度的烟气条件是极为严峻的挑战。Nafion干燥管独特的气态膜除湿、能保留目标气体的特点,为冷干直抽法CEMS提出了一个样气处理的新方案。Nafion管为核心的GASS样气处理系统,集絮凝过滤、除酸雾、Nafion管干燥和在线酸性气体露点监测为一体,可彻底解决冷干直抽法CEMS中冷凝水析出和低量程SO2易溶于冷凝水的难题,是一种创新的冷干直取法CEMS样气处理技术。通过实验室试验,手持式CEMS应用实验,和嘉兴发电厂8号机组"超低排放"CEMS的应用,证明GASS样气处理系统非常适合在燃煤电厂"超低排放"CEMS中应用。  相似文献   
7.
针对经典的S809翼型,耦合基于低速预处理的流场求解方法和序列二次规划方法,开展针对翼型升阻比的翼型气动外形优化设计研究。优化结果显示优化翼型具有较大的翼型前缘半径和较平坦的上表面。数值计算结果表明,优化翼型在设计点1的状态下升阻比提高43.3%,在设计点2的状态下升阻比提高48.9%。进一步数值验证表明,优化翼型在雷诺数为5.0×105状态下的最大升力系数从S809翼型的1.140增大到1.297,在雷诺数为1.0×106状态下的最大升力系数从1.236增大到1.418。在优化翼型的基础上,开展翼型气动外形人工修型研究,数值模拟表明修型翼型能更好地消除气流分离,从而进一步增大翼型升力系数、减小翼型阻力系数。  相似文献   
8.
简述了小波包变换的基本原理及利用小波包对电压信号进行分解的方法。针对铝电解槽电压波动信号的频谱特点。采用小波包分析方法提取了电压信号的特征向量。将信号分解到8个频段内。进行预处理得到频段能量特征向量。应用BP神经网络建立了特征向量到振针信息元之间的映射。仿真结果表明,小波包分析能够有效地将隐藏在正常电压信号之中的早期弱故障信号提取出来,从而发现槽子的早期不良症状。  相似文献   
9.
阙肖峰  聂在平  胡俊 《电子学报》2007,35(11):2062-2066
针对组合目标电磁散射问题,采用一类新的混合场积分方程进行分析.通过合理选择比例系数组合表面电场和磁场积分方程,构造出具有良好收敛性的阻抗矩阵.MLFMA的迭代求解采用广义最小残差方法(GMRES),结合预条件技术进一步减少迭代次数,加速计算并提高处理电大尺寸导体介质复合目标的能力.研究了几类典型目标电磁散射特性并比较了计算效率,数值算例验证了该方法的准确性和高效性.  相似文献   
10.
目的:观察川芎嗪预处理对大鼠视网膜缺血再灌注损伤后视网膜电流图的影响.方法:采用前房灌注法建立大鼠视网膜缺血再灌注损伤模型,设置正常组、缺血再灌注组、5min缺血预适应组、川芎嗪预处理组,分别于缺血前,缺血30min时,再灌注1h,12h,24h,72h,168h检测双眼各时期FERGb波及OPs(O2)波波幅,分别计...  相似文献   
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