问题 单项选择题

洋地黄治疗房颤,减慢心室率的最主要机制是()

A.直接延长房室结的不应期

B.兴奋迷走神经

C.减慢心房的传导

D.降低心房自律性

E.降低窦房结自律性

答案

参考答案:B

选择题
问答题

Task 5
Conversation: The following are two business letters. After reading them, you should give brief answers to the 5 questions (No. 56 through No. 60) that follow. The answers should be no more than 3 words. They should be written after the corresponding numbers on the Answer Sheet.

Letter One

Dear Sirs,
On 5th October I bought one of your expensive "Apollo" fountain pens from Julian’s, a big department store of this town. Unfortunately I have been unable to use the pen because it leaks and fails to write without making blots. I am very disappointed with my purchase.
On the advice of Julian’s manager I am returning the pen to you and enclose it with this letter for correction of the fault.
Please arrange for the pen to be fixed or replace it with a new one and send it to me as soon as possible.
Letter Two

Dear Sirs,
Thank you for your letter of 9th October enlosing the defective "Apollo" fountain pen, received today. We very much regret that the pen you bought has given you trouble.
Normally each of our pens is individually examined before being passed into store and it is hard to understand why this one escaped examination. We have passed your pen to our quality control department for inspection and report. Meanwhile, we are arranging to replace your pen with a new one.
We extend our apologies for the inconvenience this matter has caused you, but are confident that the replacement pen you will be receiving will prove satisfactory.

When was the Letter One writtenIt was written ______.