长期应用糖皮质激素可引起
A. 低血钙
B. 高血钾
C. 低血钠
D. 高血磷
E. 钙、磷排泄减少
When we arrived at the airport, we were told our flight ().
A. cancelled
B. had cancelled
C. has been cancelled
D. had been cancelled
下列几种浅基础类型,哪种最适宜用刚性基础假定? ()
A. 独立基础
B. 条形基础
C. 筏形基础
D. 箱形基础
稀有碱基常出现于
A. rRNA
B. tRNA
C. 冈崎片段
D. huRNA
E. mRNA