Tom often plays basketball _____ his friends.[ ]
A. to
B. on
C. with
D. at
答案:C
桡骨干单骨折多发生在()。
A.上1/3
B.中1/3
C.下1/3
D.中下1/3交界处
E.中上1/3交界处
引起左心室后负荷增高的主要因素是()
A.肺循环高压
B.体循环高压
C.回心血量增加
D.主动脉瓣关闭不全
E.血细胞比容增大