R-3-甲基-2-丁醇的Fischer投影式是().
参考答案:
How surprising ______ he should have refused to come !
A.is he that
B.he is that
C.is it that
D.it is that
癫痫的诊断原则是()
A.只要确定是否为癫痫即可
B.只要确定是何类型即可
C.只要确定是原发还是继发即可
D.首先确定是否癫痫,其次制定类型和病因
E.首先确定病因和类型