脑灌注显像注射显像剂前30分钟～1小时，受检者口服过氯酸钾400mg，封闭（）、（），以减少这些组织对显像剂的摄取和分泌。
参考答案：脉络丛；甲状腺和鼻黏膜
Your cousin is said _____ a new computer programme recently, but do you know when he will finish it? [ ]
A. to design
B. to be designing
C. to have been designing
D. to have designed
原状地层电阻率符号为（）。
A.Rxo
B.Ri
C.Rt
D.Ro
