女,16岁,发现左颈部肿块两年,CT如图所示,最可能的诊断为()
A.囊状水瘤
B.咽部神经鞘瘤
C.咽旁脓肿
D.左侧鳃裂囊肿
E.囊性转移癌
参考答案:D
在检查控制臂过程中,控制臂不应()。
She had never been to the Great Wall before.Today she saw it the first time. [ ]
A. at
B. for
C. in
D. by