Effect of antioxidant in endothelial cells exposed to oxidized low-density lipoproteins

Antioxidants such as probucol and alpha-tocopherol have been shown to attenuate the oxidation of low-density lipoproteins (LDL) and atherosclerotic lesions in animal models of atherosclerosis. The purpose of this study is to determine the protection effect of antioxidants on endothelial cells when exposed to oxidized and native LDL. In a cell-free system, we found that probucol, alpha-tocopherol, and ascorbic acid inhibited copper-induced LDL oxidation by a dose-dependent fashion (from 1 microM to 10 mM). In porcine aortic endothelial cells, antioxidants alone did not change basal endothelin-1 (ET-1) secretion. When porcine aortic endothelial cells were exposed to LDL and oxidized-LDL, both of them stimulated ET-1 secretion dose-dependently, whereas oxidized-LDL elicited higher ET-1 secretion. However, probucol, alpha-tocopherol, and ascorbic acid did not prevent LDL or oxidized-LDL induced ET-1 secretion. Furthermore, nimodipine inhibited both of native and oxidized LDL induced ET-1 secretion. Since Ca2+ channel blocker reduced the elevation of induced ET-1 secretion, the [Ca2+]i is possibly involved for the regulation of ET-1 secretion. Our results suggest that antioxidants can only prevent the oxidation of LDL rather than oxidized and native LDL-induced ET-1 secretion in vascular endothelial cells. The increase in the [Ca2+]i of endothelial cells through the opening of voltage-dependent Ca2+ channels may be involved in the LDL-induced ET-1 release.     

Exponential stability in mean square of neutral stochastic differential functional equations

The aim of this paper is to investigate the exponential stability in mean square for a neutral stochastic differential functional equation of the form d[x(t) − G(x_t)] = [f(t,x(t)) + g(t, x_t)]dt + σ(t, x_t)dw(t), where x_t = {x(t + s): − τ s 0}, with τ > 0, is the past history of the solution. Several interesting examples are a given for illustration.     

a—Si：H／c—Si异质结的高频C—V特性

测量了GD a-Si:H/n-c-Si异质结的高频C-V特性,由平带电压的偏移,计算了有效表面电荷和表面态密度,应用突变异质结能带模型对结果作了分析.     

HJD04系列交换机三方通话和会议电话的实现

ＨＪＤ０４系列交换机是目前国内首选的优秀机种，系统中三方通话和会议电话功能的实现有其独到之处，本文对此作一简要介绍。     

涡轮叶片材料及制造工艺的研究进展

针对航空发动机涡轮叶片的工作环境和使用要求,介绍了提高涡轮叶片耐温能力的两种途径,即加强叶片冷却和提高叶片材质自身的耐温性能。文中着重评述了用作叶片材料的合金及其制造工艺的研究进展与发展趋势。     

直接检测IT15基因（CAG）n重复对亨廷顿氏病进行基因诊断

应用巢式ＰＣＲ和变性聚丙烯酰胺凝胶电泳放射自显影鉴定ＩＴ１５基因（ＣＡＧ）ｎ串联重复序列拷贝数的技术，对４０名正常中国人以及徐州和浙江两大亨廷顿氏病家系４６名家庭成员进行了分析。结果表明，正常中国人ＩＴ１５基因（ＣＡＧ）ｎ拷贝为１６左右，而ＨＤ患者的突变基因（ＣＡＧ）ｎ拷贝数均大于４０，两者之间不重叠。     

远近围岩含水不同对套管岩压外载的影响

建立了围岩多层性受载模型，按粘弹对应原理，对均匀地应力场下及非均匀地应力场下蠕变引起的岩压外载及因远近含水量不同而引起的变化，从理论上进行了分析。     

用波形迭代法分析非均匀多导体传输线的时域响应

本文从频域电报方程出发推出了一个描述传输线ABCD矩阵的微分方程,将传输线时域响应分析从微分方程的边值问题转化为数学上更易求解的初值问题。然后利用波形迭代法数值求解非均匀传输线的ABCD矩阵,证明了一个关于迭代收敛性的定理,并据此采取了旨在加快收敛速度的将传输线分割成许多相互级联的子网络的步骤。传输线的ABCD矩阵求得后,便可借用付里叶变换和卷积技术对具有线性、非线性负载的传输线时域响应进行分析。给出的应用实例表明,诙分析方法是有效而可靠的。     

Inhibition of TNFalpha attenuates infarct volume and ICAM-1 expression in ischemic mouse brain

The family physician occupies a front-line position in the detection and treatment of emotional problems and psychiatric illnesses. The practice pattern of the family physician necessitates an efficient, effective model of psychotherapy The BATHE technique is a brief psychotherapeutic method that addresses the patient's background issues, affect and most troubling problem. The emphasis of the interview then shifts to how the patient is handling the problem and a demonstration of empathy by the physician. Some of the challenges in psychotherapy are presented, and cases in which the BATHE technique was used are described.     

相关杂波的AR谱模型及其研究

研究了相关雷达杂波功率谱特性的ＡＲ模型及其模拟方法，提出了具有约束条件的修正ＬＥＶＩＳＯＮ递推算法和ＡＲ模型阶数估计方法，并与现有功率谱估计方法进行了比较，同时给出了计算机模拟结果。