嗜水气单胞菌HEC毒素苗对鲫鱼的免疫效果的初步研究

用嗜水气单胞菌强毒株BSK－10和TPS－30的HEC毒素苗分别免疫鲫鱼,以不同嗜水气单胞菌菌株攻毒,测定免疫保护率,结果显示：BSK－10HEC毒素苗对同型菌株攻击保护率达90％－100％,对异型菌株攻击的保护无效,为0－20％;TPS－30HEC毒素苗对,同源菌株攻击的保护率达100％,对同型菌的保护率为75．5％－100％,对异型菌株的保护率为44．4％－100％,经统计检验,TPS－30毒素苗对10株攻毒株的保护除1株无效外,其余均效果极显著或显著,对血清型不同的菌株的免疫保护率没有区别。     

实现远程访问需要考虑的因素及其方案

给出了远程用户访问企业网的几种方式，分析了实现远程访问需要考虑的各种因素，给出了基于WindowsNT的企业网远程访问具体解决方案。     

两种常用加密算法的研究

本文介绍了DES算法和RSA算法的实现过程,DES算法实现简单,但KEY容易泄露;RSA算法很好地解决了DES算法的缺点,但实现困难。     

Angiotensin-converting enzyme 2 in acute respiratory distress syndrome

Angiotensin-converting enzyme (ACE) and ACE2 are highly homologous metalloproteases that provide essential catalytic functions in the renin-angiotensin system (RAS). Angiotensin II is one key effector peptide of the RAS, inducing vasoconstriction and exerting multiple biological functions. ACE cleaves angiotensin I to generate angiotensin II, whereas ACE2 reduces angiotensin II levels. Accumulating evidence has demonstrated a physiological and pathological role of ACE2 in the cardiovascular systems. Intriguingly, the SARS coronavirus, the cause of severe acute respiratory syndrome (SARS), utilizes ACE2 as an essential receptor for cell fusion and in vivo infections. Moreover, recent studies have demonstrated that ACE2 protects murine lungs from acute lung injury as well as SARS-Spike protein-mediated lung injury, suggesting a dual role of ACE2 in SARS infections and protection from ARDS. Received 18 May 2006; received after revision 12 March 2007; accepted 24 April 2007     

Pancreatic islet β-cell deficit and glucose intolerance in rats with uninephrectomy

This study was performed to examine the effect of chronic renal impairment and renin-angiotensin system (RAS) activation induced by unilateral nephrectomy (UNX) on the development of pancreatic islet β-cell deficit and glucose intolerance. Sprague-Dawley rats were randomized into three groups: untreated UNX (n = 10), UNX treated with the angiotensin-converting enzyme inhibitor lisinopril (n = 8) and sham operation (n = 10). Blood glucose, serum insulin, renal function and histological changes of kidney and pancreas were examined 8 months postoperation. Compared with the sham rats, UNX rats developed renal impairment, insulin deficiency and glucose intolerance. Histological staining revealed an islet β-cell deficit associated with increased immunoreactivity for angiotensin and angiotensin type 1 receptor in UNX rats. Treatment with lisinopril significantly improved renal dysfunction, hyperglycemia, insulin secretion and islet RAS expression. These data suggest that chronic renal impairment and RAS activation may contribute to islet β-cell loss and glucose intolerance. RAS blockade may therefore prevent these disorders. Received 29 August 2007; received after revision 25 September 2007; accepted 27 September 2007     

不同水文模型在半干旱地区的应用比较研究

分别采用新安江模型、HEC模型和TOPMODEL模型对滦河宽城流域进行洪水模拟计算,认为蓄满产流模型可以进行半干旱地区洪水模拟和预报分析,在计算时段为3 h的情况下,采用历史水文资料无法区别出产流模式.如果采用超渗产流一类的模型,计算时段要小于0.5 h.     

我国产业结构变迁的RAS分析

技术进步与投入相对价格的变化都将导致整个国民经济生产结构变化, 然而, 从已知投入产出系数矩阵变化反向推导出引致变化的原因并不容易. 本文试图将经典的投入产出表更新与调平技术RAS拓展为产业结构变化的分析模型, 在事先不预设产业结构变化是需求驱动还是供给驱动的条件下, 把投入系数矩阵的变化分解为列变化、行变化和特定变化. 从而, 定量分析我国产业结构变动及其原因. 我们的研究发现, 我国产业结构在向高度化发展的同时, 劳动密集型产业仍在高速增长, 这反映出我国区域经济发展的不平衡性, 产业升级内化为地区间产业转移的效应.     

投入产出分析的RAS方法的加权修正和推广——RTALS方法及其数学模型

确定了Ｉ／Ｏ中直耗系数变动对“全局”的影响程度因子，并把该因子作为直耗系数的权重，对ＲＡＳ法进行修正推广。提出了ＲＴＡＬＳ方法及其数学模型。     

序列投入产出表的研究

探讨如何根据离散的投入产出表生成逐年连续的投入产出表,即序列投入产出表的方法,以扩大静态投入产出理论的应用.在对于基本RAS法、二阶段RAS法等进行了系统研究的基础上,提出了分块应用RAS法.该方法首先对于直接消耗系数矩阵A按变化类型的不同分块,然后对于每块分别应用RAS法.按照本文中提出的方法进行比较,结果是分块RAS法优于二阶段RAS法,二阶段RAS法优于基本RAS法.     

基于多语言编程的拨号上网管理方法与实现

通过对Windows API中网络服务函数(RAS)的调用,深入Windows内核,实现了应用程序对系统"网络与拨号连接"的直接控制.并利用VC 将其封装在动态连接库中,然后再通过Delphi的套接字机制在局域网内服务器和客户机之间建立起一种通信模式,最终实现了用户在客户端对服务器拨号连接的间接操作和自动管理.当服务器端应用程序处于后台运行时,客户端用户在本地机上就可通过发送各种命令及参数对服务器端的RAS连接进行直接操作,同时服务器端应用程序还可进行自动管理,为RAS的维护带来了很多方便.