中文摘要：

随着化学和生物技术的飞速发展，多糖已经成为生命科学研究的热点领域之一，其结构和生物活性的关系对于新药的研发显得尤其重要。本文从多糖结构与其三大活性抗肿瘤、抗病毒、抗凝血的角度，具体阐述多糖的结构如主链结构、取代基修饰、分子量、聚合度等对生物功能的影响，为定向合成设计糖类药物和先导化合物的改造提供参考。

英文摘要：

In the past several years, a lot of novel polysaccharides have been discovered, and their biological and pharmacological functions have also been detected. This paper reviews the recent researches on the relationship of structure and function of polysac- charides, especially on the activity of anti-tumor, antivirus and anti-coagulant. The relationships of structures of polysaccharides such as the main chain, substitution groups, molecular weight and polymerization degree, and the activities are summarized. It is expected to be helpful for the target-oriented synthesis of polysaccharide drugs and lead compounds optimization.