男性，70岁。超声检查见主动脉瓣增厚、钙化．开放受限，关闭不拢_爱下问搜题

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问题单项选择题案例分析题

男性，70岁。超声检查见主动脉瓣增厚、钙化．开放受限，关闭不拢，升主动脉扩张。诊断为主动脉瓣狭窄伴关闭不全，拟行手术治疗。

该患者主动脉瓣手术的最佳方案是（）

A.置换机械瓣

B.置换生物瓣

C.自体肺动脉瓣移植

D.主动脉根部移植

E.主动脉瓣成形

答案

参考答案：B

选择题

在25℃时，分别用pH=9、pH=10的两种氨水中和同浓度、同体积的盐酸，消耗氨水的体积分别为V₁和V₂，则V₁和V₂的关系是（　　）

A．V₁=10V₂

B．V₁＞10V₂

C．V₁＜10V₂

D．V₂＞10V₁

填空题

用方框中所给的单词的适当形式填空。

noise, develop, five, harm, help

1. With the ________ of the industry, China has developed rapidly.
2. I don't like rock music because it's too ________.
3. Two ________ of the visitors come from Japan, the others are from America.
4. Light pollution is ________ to our eyes.
5. We aim ________ the poor students to come back to school.