多根多处肋骨骨折的反常呼吸,在吸气时下列哪项不正确()
A.软化区胸壁内陷
B.纵隔摆向健侧
C.膈肌上升
D.患侧气道内的气体进入健侧肺脏
E.影响静脉血液回流
参考答案:D
男性,20岁,1周来四肢对称性出现紫癜,略突出皮面伴瘙痒。该患者出现紫癜最可能的机制是()
A.血管异常
B.血小板数量减少
C.血小板功能异常
D.凝血因子缺乏
E.抗凝物质增多
I _________ my homework last night when I heard a loud knock on the door.[ ]
A. did
B. was doing
C. have done
D. had done