Scientists first studied the effects of calorie restriction on aging in the nineteen thirties.

VOA: special.2009.09.01

Or you could ask the question, I have this restriction enzyme, at what regions on this plasmid will it cut?

你也可以这样问,我的这种限制性内切酶,会从质粒的哪个区域切开呢

耶鲁公开课 - 生物医学工程探索课程节选

When it cuts it leaves sticky ends or un-base paired single stranded regions on each end of the part its cut and that's just a property of many restriction enzymes; not all, some cut blunt,just right down the middle.

它切割后会留下两个粘性末端,或者未配对的单链部分,这是许多限制性内切酶的特性,但不是全部,有些限制性内切酶是从中间钝切的

耶鲁公开课 - 生物医学工程探索课程节选

For Hamas leaders, this is,in some ways, a bigger victory than persuading Israel to lift its restriction on goods entering the territory.

VOA: standard.2010.06.16

If I cut both the plasmid and my DNA of interest with the same restriction enzyme I'm going to end up with the same sticky ends on both molecules.

如果用同一种限制性内切酶,来切割质粒和我感兴趣的DNA,在两个分子上就能得到同样的粘性末端

耶鲁公开课 - 生物医学工程探索课程节选

The president refers to his proposed restriction on risky behavior as the "Volcker Rule."

VOA: standard.2010.01.21

We're going to take a chromosomal DNA, we're going to digest it with this restriction enzyme, we're going to put it in this tube and run it on a gel, and we're going to see what results down here.

我们取一条染色体DNA,然后用限制酶进行分解,接着再放,在凝胶上进行电泳,之后看看结果如何

耶鲁公开课 - 生物医学工程探索课程节选

The loss of jobs and business opportunities has perhaps been more damaging than the restriction on imports, especially for those who under the blockade - cannot cross into Israel.

VOA: standard.2010.06.16

Richard Weindruch explains. "Our data show that there is about a three-fold higher risk of developing a disease of aging in those animals fed the normal diet as opposed to those that have been on caloric restriction since they were adults."

VOA: special.2009.09.01