甲状腺功能亢进症患者血清甲状腺激素浓度高于正常，血清TSH浓度常为（）
A.增高
B.变化无规律
C.正常
D.减低
E.明显增高
参考答案：D
____ is often the case, we can't find the things when we need them. [ ]
A. Which
B. When
C. What
D. As
下列腺体中既是外分泌腺，又是内分泌腺的是[ ]
A．垂体
B．性腺
C．胰腺
D．甲状腺
