二氢叶酸还原酶抑制剂为（）
A.甲氨蝶呤
B.环己亚硝脲
C.长春新碱
D.阿霉素
E.6-巯基嘌呤
参考答案：A
可以出现肌强直的周期性瘫痪属于()
A．高钾型周期性瘫痪
B．低钾型周期性瘫痪
C．正常血钾型周期性瘫痪
D．心律失常型周期性麻痹
E．甲亢型周期性麻痹
The place ___ I often visit is a place ___ salves used to be sold.
A．which ; where
B．where ; where
C．which; which
D．where; which
