cell receptor when complexed with MHC,are called antigens. The molecular properties of antigens and he way in which these properties ultimately contribute to immune activation are central to our understanding of the mmune system. This chapter describes some of the molecu- Complementarity of Interacting Surfaces of Antibody(left) lar features of antigens recognized by B or T cells. The chap and Antigen(rig ter also explores the contribution made to immunogenicity by the biological system of the host; ultimately the biological system determines whether a molecule that combines with a a Immunogenicity Versus Antigenicity Bor T cells antigen-binding receptor can then induce an im
投资组合( P o r t f o l i o )管理的目的是:按照投资者的需求,选择各种各样的证券和其他资产 组成投资组合,然后管理这些投资组合,以实现投资的目标。投资者的需求往往是根据风险 (r i s k)来定义的,而投资组合管理者的任务则是在承担一定风险的条件下,使投资回报率 (r e t u r n)实现最大化