咖啡因与解热镇痛药合用治疗头痛,其机制主要是
A.扩张外周血管,增加散热
B.抑制大脑皮质
C.收缩脑血管
D.抑制痛觉感受器
E.使镇痛药在体内灭活减慢
参考答案:C
乳牙期矫治适应症有 ()
A.前牙反牙合,下颌前突
B.后牙反牙合
C.深覆牙合
D.扭转牙
E.开牙合
—Welcome to our city! I hope you can have a good time here.
— I'm sure I will . _______ . [ ]
A. Thank you
B. Never mind
C. That's 'right
D. Good idea