【单选题】
7. 普萘洛尔不具有的作用
①
阻断心脏β受体，降低窦房结、房室结的自律性
②
大剂量或高浓度是可抑制窦房结及浦氏纤维的传导
③
治疗量时可促进K+外流，缩短APD和ERP，相对延长ERP
④
治疗量时可产生膜稳定作用，延长APD和ERP
⑤
高浓度或大剂量时可产生膜稳定作用，而延长APD和ERP
【单选题】
7. She is poor ______ she can hardly get anything to eat.
①
as much as
②
too much so that
③
so much so that
④
much more than
【单选题】
7. ______ the help of my teacher, I caught up with the other students.
①
Under
②
In
③
With
④
On