When ________different cultures, we often pay attention only to the differences without

noticing the many similarities.[      ]

A. compared    

B. being compared

C. comparing    

D. having compared

动脉导管未闭的特征性体征是

A．左心房、左心室增大

B．水冲脉

C．股动脉枪击音

D．胸骨左缘第2肋间连续性机器样杂音

E．肺动脉瓣区第二音亢进、分裂