麻黄碱的生物活性有
A.收缩血管
B.兴奋中枢神经
C.缓解平滑肌痉挛
D.增加汗腺分泌
E.解毒
参考答案:A,B,C,E
Reality is not the way you wish things to be, nor the way they appear to be, _________ the way they actually are.
A.as
B.or
C.but
D.and
简述线型高分子量缩聚物生产中影响分子量的主要因素。