揭开免疫的秘密：MHC如何和抗原相遇

一个受到病毒感染的细胞,是如何通过免疫系统的杀伤者T细胞,在其自身表面触发起一种攻击活动的呢?简短答案,就是T细胞通过一种型-I主要组织相容性复合(MHC)蛋白质,识别出现在受感染细胞表面上的病毒蛋白质片段,这种现象,称作"抗原表述".但是,隐匿在这种答案中的秘密,多年来一直令免疫学家     

Fourth World Conference on Women: the Namibian perspective

This consideration of some of the issues raised at the Fourth World Conference on Women (WCW) from a Namibian perspective begins by mentioning the pernicious nature of domestic violence and briefly summarizing some of the main points raised at a 1994 symposium on domestic violence. The discussion continues by noting that Namibia's report for the WCW reaffirms that it is crucial for women to be involved in the decision-making process at all levels. Next, the paper notes that traditional male attributes of strength are losing their importance in a world that values mental alertness, intuition, and traditional female qualities of love and service. This has led to a call for a transformation of society supported by the education of women and their economic empowerment. The essay ends by defining an empowered person as possessing a belief in the ability of human intervention to change the world, a sense of self-worth, a sense of the self as a viable agent of change, and a notion of what constitutes a better life.     

缺氧对脑星状细胞GAPDH和β—Actin基因表达的影响

目的：样本ＲＮＡ加样量的差异是影响Ｎｏｒｔｈｅｒｎ杂交ＲＮＡ分析和反转录ＰＣＲ（ＲＴ－ＰＣＲ）半定量分析的重要因素。因５－磷酸甘油醛脱氢酶（ＧＡＰＤＨ）和β肌动蛋白（β－ａｃｔｉｎ）ｍＲＮＡ水平一般相对恒定,常用于基因表达研究时样本加样量的校正。但有报道表明某些因素对ＧＡＰＤＨ和β－ａｃｔｉｎ的ｍＲＮＡ水平有一定影响。脑星状细胞（ＡＣ）是近年来神经科学的研究热点之一,有关其基因的研究得到广泛的重视     

静电陀螺寻北仪的力学原理

静电陀螺仪是当今世界上精度最高的陀螺仪,研制静电陀螺寻北仪是为了寻求高精度的方位测量仪器。采用静电陀螺仪组成寻北仪可采用以下两种方式：力反馈方式和自由陀螺方式。前者水平方向包含两个力反馈回路,通过测量反馈回路电流得出方位角。后者陀螺自由转动数分钟,通过测量静电陀螺水平轴偏角得出方位角。该文讨论了力反馈方式和自由陀螺方式静电陀螺寻北仪力学原理,其中包括两种方式下坐标变换及获得方位角的算法推导,并得出结论。