虽然科学家还不确定安慰剂效应的具体原理，但他们也已经积累了一些相关知识，知道如何触发这些效应。
Though scientists do not know how exactly how placebos work, they have accumulated a fair bit of knowledge about how to trigger the effect.
本篇文献回顾发现在一般的情况下，不同种类的非处方人工泪液间或与安慰剂相比时，是否会提供相似缓解的征兆和症状是不确定的。
The review found that, in general, there was uncertainty whether different OTC artificial tears provide similar relief of signs and symptoms when compared with each other or placebo.
应用推荐