免疫印迹（immunoblot）
参考答案：
蛋白质样品经聚丙烯酰胺凝胶电泳分离后转移到硝酸纤维膜上，然后用标记抗体揭示特异抗原存在的分析测定方法。
The witnesses(证人) of the accident said that the lorry _______ very fast at the crossroads when the accident happened.
A．is traveling
B．had travelled
C．was to travel
D．was travelling
_______ could be judged from her eyes that she was terribly sorry for what she _______.
A．As…had done
B．That…did
C．As…did
D．It…had done
