目的对一个三代四人发病的DDH家系进行研究，以期发现与DDH发病相关的致病基因或易感基因。方法对一个三代四人发病的DDH家系中的3个......

Turnip mosaic virus (TuMV) which has several strains causes the most important virusdisease in Chinese cabbage in terms ......