清华大学工会电子会务系统研究与实践

清华大学工会电子会务平台采用J2EE技术架构,以网络为手段,为工会会员和社会公众提供了网上信息发布、会员信息管理、运动会管理、网上报名、教代会电子提案、意见与答复等服务内容.该文就屯电子会务平台系统的概念、组成模型和设计进行了论述.该平台已经在清华大学工会日常工作及各项重大活动中使用,取得了良好的应用效果.     

大学英语四、六级考试改革及其启示

大学英语四、六级考试在考试内容、记分系统和考务管理上发生了重大改革。如何预测和认识英语四、六级考试改革的潜在影响对把握改革良机、提高大学英语教学质量和减少应试教育负面影响有重要意义。在此基础上要重视听说和写等技能的培养;要加强不断线教学,提高教学资源利用率;要正确对待分数,实现科学评估。     

论胡适的妇女解放思想

胡适认为传统的“男尊女卑”、“三从四德”等封建纲常礼教是中国妇女解放的最大障碍。他反对缠足,反对片面的贞节观,主张男女平等、婚姻自由。他特别强调通过教育培养中国妇女的“自立”精神和能力,使妇女全而自由的发展,成为具有独立意志的、社会的人,从而使近代中国社会愚昧、落后的面貌有所改观。     

IPv6 技术及其安全机制研究

IPv6协议是新一代互联网协议，有效地解决了当今IPv4协议面临的各种问题，特别是在网络安全方面IPv6提供了更完善的安全机制。本文讨论了IPv6的基本技术原理和核心技术，并着重对IPv6安全机制进行了详细分析，提出了IPv6安全机制仍存在的若干问题。     

Influence of green tea polyphenols on mitochondrial permeabi lity transition pore and Ca2+ transport

The authors investigated the influence of green tea polyphenols (GTPs) on the liver mitochondria permeability transition pore (PTP) opening through mit ochondria swelling and change of mitochondria membrane potential. The data showe d that GTPs had obvious protective effect on the Ca2+-induced PTP opening in a d ose-dependent manner detected by mitochondria swelling. The results were obtain ed by measuring the change of mitochondria membrane potential through Rh 123. Further experiments were conducted to examine the detailed influence of GTP s on Ca2+import and export of mitochondria. The results showed that GTPs h ad rem arkably inhibitory effect on the Ca2+-induced Ca2+ import in mitoch ondria; and t hat they could accelerate Ca2+-release from mitochondria. Our data provid e an al ternate interpretation of the potent protective function of GTPs on cell against apoptosis.     

阳离子鉴定实验中"异常"现象的探讨

在进行阳离子分析实验的操作时,由于实验中溶液介质的变化或外界环境的影响,使部分阳离子Bi3 、Cd2 、AsⅢ等鉴定实验出现"异常"现象,提出了如何得到正确实验现象和结论的具体措施.     

智能建筑在我国崛起后的思索

智能建筑是信息时代的必然产物,建筑物智能化程度随科学技术的发展而逐步提高。发展我国智能建筑应树立“以人为本,按需集成”的思想,并逐渐规范行业术语,加速制定相关标准,充分利用当今的信息科技,加强与国际间的合作与交流,不断提高我国智能建筑技术水平。     

可数性公理与分离性公理关系的几个结论

通过几个常见特殊空间拓扑性质的讨论,给出几个结论,说明可数性公理与分离性公理是互相独立的,它们刻画的空间没有必然的联系.     

Review:DNA-damage response network at the crossroads of cell-cycle checkpoints, cellular senescence and apoptosis

Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycle, cellular senes- cence, apoptosis regulation, cancer development and tumor responses to cancer treatment has become eminently apparent. Extensive research on tumor suppressor genes, oncogenes, the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways, referred to as the DNA-damage response network, are tied to cell proliferation, cell-cycle arrest, cellular senescence and apoptosis. DNA-damage responses are complex, involving “sensor” proteins that sense the damage, and transmit signals to “transducer” proteins, which, in turn, convey the signals to numerous “effector” proteins implicated in specific cellular pathways, including DNA repair mechanisms, cell-cycle checkpoints, cellular senescence and apoptosis. The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation. In addition, several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle, DNA repair/recombination and cellular senescence, effects that are generally distinct from their function in apoptosis. In this review, we report progress in understanding the molecular networks that regulate cell-cycle checkpoints, cellular senescence and apoptosis after DNA damage, and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.     

Molecular dynamics simulation study on behaviors of liquid 1,2-dichloroethane under external electric fields

ＩＮＴＲＯＤＵＣＴＩＯＮＭｏｌｅｃｕｌａｒｄｙｎａｍｉｃｓ (ＭＤ)ｓｉｍｕｌａｔｉｏｎｗａｓｆｏｕｎｄｔｏｂｅａｎｉｍｐｏｒｔａｎｔｍｅｔｈｏｄｏｌｏｇｙｆｏｒｓｔｕｄｙｏｆｃｏｎｄｅｎｓｅｄｍａｔｔｅｒ (Ｔｓｕｚｕｋｉｅｔａｌ.,1 996) .Ｋｉｓｅｌｅｖａｎ