男性患者，45岁。有动脉粥样硬化病史。突然感到剧烈刀割样胸痛2小时，向背部放射。查体发现主动脉瓣区可闻及舒张期杂音。考虑为主动脉夹层可能。下列哪一项是其常见的胸片表现（）
A.主动脉弓部和降主动脉上部影增宽
B.主动脉影狭小
C.主动脉搏动增强
D.主动脉影位置改变
E.主动脉影外形改变
参考答案：A
解析：根据病史，可以诊断为主动脉夹层，其影像表现为主动脉弓部和降主动脉上部影增宽。
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| Li Lei gets an e-mail __1__ Jackson Wilson. Jack is a high school student in Canada. He wants to __2__Chinese. Dear friend, My name is Jack Wilson. I am from Toronto, __3__. I am 13 years old. I'm a schoolboy. I know China is a great __4__. I want to __5__ friends in China and I want to learn Chinese. There are nineteen students in __6__ class. My classmates are from six countries. They are learning English. My parents are from France. They __7__ French. I speak English and French. There are many Chinese __8__ in Toronto. I want to learn Chinese, __9__ I don't have any Chinese textbooks. Could you __10__ me? Please write back soon. Thank you. Jack Wilson | |||
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