英语语法分析

Does sildenafil cause myocardial infarction or sudden cardiac death?

伟哥会引起心肌梗死或心源性猝死吗？

He said sildenafil worked at least as well as melatonin, a jet-lag treatment.

他还认为昔多芬的作用至少和目前用于治疗时差综合症的退黑激素的作用类似。

In the study, researchers administered small doses of sildenafil to hamsters before adjusting the cycles of light and dark they lived in.

在这项研究中，研究者在调整仓鼠所处环境的白昼规律前，给其小剂量的昔多芬。