吗啡作为全球最著名的天然产品之一，不仅是海洛因、羟考酮等半合成阿片类药物的前体，同时亦是用于逆转过量作用的纳洛酮的基础分子。加州大学伯克利分校（University of California, Berkeley）研究员Richmond ...

LOS ANGELES, July 11 (Xinhua) -- A substantial majority of California voters believe that U.S. democracy is in serious trouble, according to a new poll recently published by the Institute of ...