Immune responses to DNA vaccines

DNA vaccines, based on plasmid vectors expressing an antigen under the control of a strong promoter, have been shown to induce protective immune responses to a number of pathogens, including viruses, bacteria and parasites. They have also displayed efficacy in treatment or prevention of cancer, allergic diseases and autoimmunity. Immunologically, DNA vaccines induce a full spectrum of immune responses that include cytolytic T cells, T helper cells and antibodies. The immune response to DNA vaccines can be enhanced by genetic engineering of the antigen to facilitate its presentation to B and T cells. Furthermore, the immune response can be modulated by genetic adjuvants in the form of vectors expressing biologically active determinants or by more traditional adjuvants that facilitate uptake of DNA into cells. The ease of genetic manipulation of DNA vaccines invites their use not only as vaccines but also as research tools for immunologists and microbiologists. Received 26 October 1998; received after revision 3 December 1998; accepted 3 December 1998     

Immunomodulatory properties of cystatins

Cystatins are natural tight-binding reversible inhibitors of cysteine proteases. Because these cysteine proteases exist in all living organisms and because they are involved in various biological and pathological processes, the control of these protease functions by cystatins is of cardinal importance. Cystatins are found in mammals but cystatin-like molecules are also present in mammals and parasites. In the immune system, cystatins modulate cathepsin activities and antigen presentation. They also induce tumor necrosis factor α and interleukin 10 synthesis, and they stimulate nitric oxide production by interferon γ-activated murine macrophages. In turn, nitric oxide has inhibitory activity on cysteine proteases, especially those from parasitic protozoa. Cystatins isolated from parasitic nematodes also have immunomodulatory activities that are distinguishable from those induced by lipopolysacharide-like molecules from endosymbiotic bacteria. On the whole, cystatins and cystatin-like molecules belong to a new category of immunomodulatory molecules. Doubtless increasing data will improve our knowledge of this property, leading to practical applications in immunotherapy. Received 11 April 2002; accepted 18 April 2002 RID="*" ID="*"Corresponding author.     

比较法视域内立法提案权的民主化

以民主的理念和原则为衡量标准,审视我国中央立法机关各提案主体的提案权,指出其中的一些问题和不足,并在和国外比较的基础上提出了相应的措施和建议。     

数学的形态与教师的任务

数学有3种形态:原始形态、学术形态、教育形态.教师的主要任务在于把学术形态的数学转化成教育形态呈现给学生,给予学生一个“平易近人”的数学.要做好这一点,使数学生活化、立体化、简单化、结构化、美化是较为有效的做法.     

面向局部定点区域的微型气象监测系统设计与试验研究

针对大型气象监测站成本高、覆盖范围有限、灵活性差的问题,设计了一套面向局部定点区域的智能化微型气象监测系统。首先,基于树莓派Raspberry Pi 4B平台开发了一套微型气象数据采集装置,可实现多种气象参数的实时采集与传输。然后,基于Qt开发了一款服务端软件,实现了针对前端采集气象数据的接收、存储、管理和可视化显示。前端采集系统实现了多种气象信息的综合检测,且系统功能可靠稳定;服务端系统实现的大数据管理和图形化显示,增强了系统可读性和实用性。该系统不仅能为气象数据的联合分析提供可靠数据源,也为业界开发相关商业产品提供了借鉴思路。     

一种MPEG2媒体同步控制算法

针对MPEG2软件解码器,提出了一种媒体同步控制算法。该算法无需调整解码器的本地系统时钟,而是以音频流为主媒体流,视频流为从媒体流,音频的播放速率保持不变,利用基于相同时间基点的媒体单元的播放时间标签,调整视频的播放帧率来实现媒体同步。同步调整后视频的同步比例由调整前的54.84%提高到99.52%,音视频的同步比例由调整前的5.07%提高到98.36%。结果表明,该算法可以实现解码器的媒体同步,满足用户提出的感知服务质量要求。     

民间艺术中“脸”的形态表现

“脸”作为一个视觉语言，是人类始终关注的话题，自然形态中的脸只是作为个体存在的符号，是一种个体标记，人类为了满足宗教、战争和美化身心的种种需要，以符号为手段的脸的艺术造型形式是原始先民对人自身的存在形式不满足而进行的改造，新的形式从此就应运而生。脸作为一种符号，其最初的呈现状态是以纹样的方式展现出来的，被赋予了神秘的色彩，是人类实践经验、情感以及文化的交流与发展的延续。     

水文系统预算编制工作的实践及建议

阐述了水文系统部门预算的具体编制方法,针对部门预算编制工作中存在的问题提出了相应的建议。     

课堂演示型多媒体课件的优化制作

随着计算机及多媒体技术的进步,以计算机为主体的多媒体教室也越来越普及。文章主要对应用Powerpoint优化制作和优化演示效果两方面进行了探讨。     

A survey of stackelberg differential game models in supply and marketing channels

Erratum to: J Syst Sci Syst EngDOI: 10.1007/s11518-007-5058-2The presentation of Table 2 in the original version of this article contained a few typos. The corrected Table 2 is given below.