患者，男性，70岁，74kg。13年前行二尖瓣生物瓣置换术。入院前两个月出现过短暂头晕；一周前自己突然闻及响亮的心脏杂音同时伴有胸闷、气促、尿少、乏力等症状；查体心尖部闻及Ⅲ级鸥鸣样收缩期杂音。心功能Ⅲ～Ⅳ级。心电图示：窦性心律，Ⅰ度房室传导阻滞。胸部X片示：两肺淤血并间质性肺水肿，右上腔静脉影增宽，肺容积缩小，心脏呈二尖瓣-主动脉型。超声心动图示：二尖瓣生物瓣撕裂反流；肺动脉高压（中度）。拟在全身麻醉下行二尖瓣瓣膜置换术。
该患者主要的病理生理改变为（）
A.右心室和左心房压力负荷过重
B.左心房和左心室容量负荷过重
C.左心房和肺静脉压增高
D.左心房和左心室压力负荷过重
E.一部分血液在左心房和左心室之间进行无效交流
F.左心室前向性血流减少
参考答案：B, C, E, F
| 完形填空，并完成相关练习。 | ||||
| Peter is my classmate. He is 1__________ American boy. He is from 2__________. He is tall. He has a round (圆的) face and 3__________ big blue eyes. His 4__________ is not black. It is blond (淡黄色的). Peter can 5__________ English. He can speak a little Chinese, too. It's Friday. Peter and I are 6__________ duty. We are in the classroom. We are 7__________ our homework. We are 8__________ the classroom. Peter 9__________ the blackboard and I 10__________ the floor.
11. Is Peter English? ________________________________________________ 12. What colour are his eyes? ________________________________________________ 13. Can he speak Chinese? ________________________________________________ 14. What are they doing in the classroom? ________________________________________________ |