慢性支气管炎发展成阻塞性肺气肿的过程中最先发生的病理改变是( )。
A．肺泡膨胀
B．细支气管不完全阻塞
C．肺泡壁弹性减退
D．肺小动脉痉挛
E．肺纤维化
参考答案：B
解析： 慢性细支气管炎时，管壁纤维组织增生，引起细支气管不完全阻塞，导致阻塞性通气障碍。吸气时，空气尚易进入肺泡，但呼气时，支气管回缩，阻塞加重，气体呼出困难，使肺内储气量增加而致肺气肿。
| 阅读下面短文，掌握其大意。然后从A、B、C、D四个选项中选出最佳选项。 | ||||
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