对饮水型氟中毒病区的患者采取的预防措施是()
A.多服钙剂和维生素D
B.增强患者的抵抗力
C.采用低氟水源
D.调节膳食结构
E.杜绝使用高氟化肥
参考答案:C
颅内最常见的动脉瘤是()
A、假性动脉瘤
B、夹层动脉瘤
C、囊状动脉瘤
D、梭形动脉瘤
E、混合性动脉瘤
—If you go to the post office, would you please get me a stamp?
--I am ___ willing to.
A.no more than
B.not more than
C.more than
D.no less than