门静脉栓塞声像图特点是（）
①门静脉内边缘不光滑的低回声或中等回声
②阻塞部门静脉管腔增宽
③阻塞部门静脉管腔变窄或闭塞
④部分梗阻门静脉内血流变细不规则，狭窄部血流速度增快
⑤阻塞段门静脉内无血流信号，周围有时可见小侧支血流及背离肝脏逆向血流
⑥阻塞段门静脉内无血流信号，周围有时可见小侧支血流及向肝血流
A.①②④⑤
B.①③④⑥
C.①③④⑤
D.①②④⑥
参考答案：A
| 用方框中所给单词的适当形式填空，使短文完整正确。(每个单词限用一次) | |
English. Many students said they learnt by using English. Some students had more specific 1 . Zeng Yike, for example said the best way to learn new words was by 2 English magazines. She said that memorizing the words of pop 3_ also helped a little. When we asked about studying grammar, she said, "I never study grammar. It's too 4 ." Yao Ming felt differently. He's been learning English for six years and really 5 it. He thought studying grammar was a great way to learn a language. He also thought that watching English movies wasn't a bad way 6 he can watch the actors say the words. Sometimes, however, he 7 watching movies frustrating. The monitor said that learning English was not 8 . He said that watching English-language TV helped a lot. He 9_ that doing lots of listening practice is one of the secrets of becoming a 10 language learner. |