I ____ a poem last night. [ ]
A. wrote
B. writes
C. writing
答案:A
某病人2小时呕血,量多,有血块,测血压仅在60mmHg处听到1次搏动,其失血量为总血容量的()
A.小于15%
B.15%~20%
C.20%~30%
D.30%~40%
E.>40%
细胞内途径