Gaining the knowledge ________ environmental protection will help you to become a qualified environmentalist.

A．addicted to

B．concerned about

C．related to

D．appealed to

强心苷治疗心衰的重要药理学基础是

A．直接加强心肌收缩力

B．增强心室传导

C．增加衰竭心脏心输出量的同时不增加心肌耗氧量

D．心排血量增多

E．减慢心率