便血最常见的病因是
A.局部血管损伤B.感染性疾病C.先天性畸形D.血液病E.消化道灶性病变
参考答案:E
I was awfully tired when I got home from work, but a half-hour nap ______ me.
A.revived
B.released
C.relieved
D.recovered
在分布滞后模型
称为()
A.长期影响乘数
B.过渡性乘法数
C.短期影响乘法
D.可加性乘数