营养性巨幼细胞性贫血的病因是（）
A.缺乏VitB12
B.缺乏VitB6
C.缺乏VitB1
D.缺乏乙酸
E.缺乏草酸
参考答案：A
I think the boy ______________ tomorrow.[ ]
A. going to plant a tree
B. is go to school
C. is going to playing chess
D. is going to join them
肝门内三结构是
A．肝动脉、肝静脉和肝门
B．门静脉、肝动脉和胆总管
C．脾静脉、门静脉和肝静脉
D．胆总管、胆囊管和左右肝管
E．肝动脉、肝静脉、胆总管
