苯胺盐酸盐与瓜环主客体包结物的晶体结构

用X射线单晶衍射方法研究六元瓜环和八元瓜环与苯胺盐酸盐的相互作用及其结构特征。从主客体包结配合物的晶体结构,可以看出苯胺的苯环进入了六元瓜环空腔,形成1：1包结配合物,两分子苯胺以相反的方向平行地进入八元瓜环空腔,形成了2：1包结配合物;表明苯胺与两种瓜环有不同的作用模式。     

Exclusion of germ plasm proteins from somatic lineages by cullin-dependent degradation

In many animals, establishment of the germ line depends on segregation of a specialized cytoplasm, or 'germ plasm', to a small number of germline precursor cells during early embryogenesis. Germ plasm asymmetry involves targeting of RNAs and proteins to a specific region of the oocyte and/or embryo. Here we demonstrate that germ plasm asymmetry also depends on degradation of germline proteins in non-germline (somatic) cells. We show that five CCCH finger proteins, components of the Caenorhabditis elegans germ plasm, are targeted for degradation by the novel CCCH-finger-binding protein ZIF-1. ZIF-1 is a SOCS-box protein that interacts with the E3 ubiquitin ligase subunit elongin C. Elongin C, the cullin CUL-2, the ring finger protein RBX-1 and the E2 ubiquitin conjugation enzyme UBC5 (also known as LET-70) are all required in vivo for CCCH finger protein degradation. Degradation is activated in somatic cells by the redundant CCCH finger proteins MEX-5 and MEX-6, which are counteracted in the germ line by the PAR-1 kinase. We propose that segregation of the germ plasm involves both stabilization of germline proteins in the germ line and cullin-dependent degradation in the soma.     

陕西省房地产价格波动特点、原因及对策

采用定理和定性结合的方法,分析陕西省房地产价格波动特点及影响因素.实证结果显示,陕西省新建住宅、新建商品住宅及二手住宅价格均呈平稳中温和上涨的整体运行态势.房地产价格波动的主要影响因素为政府的宏观调控政策、保障房供应、土地供给加大等.根据分析结果提出稳定房地产价格、促进陕西房地产市场健康发展的政策建议.     

三频共塔1KW中波广播发射机网络

探讨天馈匹配网络的设计,元件选取以及匹配网络的调试方法.