满族尊敬的动物有()。
A.狗
B.喜鹊
C.乌鸦
D.马
参考答案:A, B, C
I _____ the way to his office because I didn’t know how to get there.
A. was showing
B. showed
C. am shows
D was shown
IPF的发病机制尚不清楚,可能参与作用的细胞因子包括()
A.PDGF
B.IGF-1
C.ET-1
D.TGF-β
E.TNF-α