关于胆管细胞癌,下列描述哪项不对()
A.多数患者AFP阴性
B.肝硬化发生率比原发性肝癌高
C.局限性肝内胆管扩张
D.居肝脏原发性恶性肿瘤第二位
E.可有小的不规则钙化
参考答案:B
实验室制取氧气的步骤大致有①把导管移出水面 ②点燃酒精灯加热 ③检查装置的气密性 ④将反应物加入试管,用带有导管的橡皮塞塞紧并把它固定在铁架台上 ⑤排水法收集氧气 ⑥熄灭酒精灯.正确的操作顺序是( )
A.③④②⑤⑥①
B.④③②⑤①⑥
C.③④②⑤①⑥
D.④③⑤②①⑥
用所给单词的适当形式填空。
1. I don't like ______ (he) room. It's too small.
2. I need a pair of black ______ (sock) to go with my new shoes.
3. We hope ______ (arrive) at the airport around two o'clock.
4. This dictionary is not ______ (I). It's Jane's.
5. You are so _______ (luck) to have the chance to visit Michael Jordan.