硝酸甘油为临床常用抗心绞痛药物，常与β受体阻断剂合用，其重要理由为（）
A.二者均可使心率减慢
B.在心室压力改变方面可相互拮抗
C.二者均可使心室容积减小
D.二者均可使心肌收缩减弱
E.二者均可使心肌耗氧量下降有协同作用
参考答案：E
解析：硝酸甘油扩张冠脉降低容量负荷，降低心肌耗氧，但增加心率与β受体阻滞剂合用，有协同作用使心肌耗氧量下降
根据短文内容，用方框中所给词的适当形式填空
There are many different ways to spend our free time. Almost everyone has some kind of 3 . It may be something from colleting stamps to 4 model planes. Some hobbies are very expensive, but others don't cost anything at all. Some collections are worth 5 of money, others are valuable only to their owners. I know a man who has a coin collection worth several 6 dollars. A short time ago he bought a rare fifty-cent piece which cost him $ 250! He was very happy about this collection and thought the price was all right. On the other hand, my youngest brother collects match boxes. He has almost 600 kinds of them, but I wonder 7 they are worth any money. However, to my brother they are quite valuable. 8 makes him happier than to find a new match box for his collection. That's what a hobby means, I think. It is something we 9 to do in our free time just for the fun of it. The value in dollars is not 10 , but the pleasure it gives us is. |