问题
单项选择题
生理情况下心脏的正常电活动起源于
A．浦肯野纤维
B．希氏束
C．房室结
D．心内膜细胞
E．窦房结
答案
参考答案：E
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生理情况下心脏的正常电活动起源于
A．浦肯野纤维
B．希氏束
C．房室结
D．心内膜细胞
E．窦房结
参考答案：E
| 用方框内所给单词的适当形式填空，每词限用一次。 | |
3______ in her room and didn't go out. Her mother asked 4______ to have lunch. She said, "No, I don't want to have lunch." Her mother was 5______ ,"Tell me,dear. What's the matter?" Mary said with tears (眼泪) 6______ her eyes,"One of my best 7______ went to another school. She's Sally. I always 8______ with her. But now I feel lonely. "Her mother said, "Mary, everyone 9______ problems in their life. We must face them and find ways to solve them. Well, let's go 10______ and go to a movie after lunch." Mary said "OK" with a smile on her face. |