Only hours after Mr.Karzai's victory in the tainted election, President Obama welcomed the Afghan leader's pledge to eradicate corruption, but frankly warned the proof of those efforts will be not in words,but in deeds.

VOA: standard.2009.11.17

Of course, that's not the useful application for it, it's more of a proof of principle, but it does show you that you can put it in for studies in any organisms.

当然，这不是很有用的应用，这仅仅是一个原理上的证明，但它告诉你你可以把它,放到研究任何生物体中。

麻省理工公开课 - 化学原理课程节选

Of course, that's not the useful application for it, it's more of a proof of principle, but it does show you that you can put it in for studies in any organisms.

当然，这不是很有用的应用，这仅仅是一个原理上的证明，但它告诉你你可以把它,放到研究任何生物体中。

麻省理工公开课 - 化学原理课程节选