英语语法分析

Objective To explore the effects of rhonchus on senile degenerated cardiac valvular disease (DCVD)and impairment features of valvular structure and function .

目的探讨鼾症对老年退行性心脏瓣膜病（DCVD）的影响和对心脏瓣膜结构和功能损害的特征。