OK. Binary search is perhaps the simplest of the divide and conquer algorithms, and what does that mean? It says, in order to solve a problem, cut it down to a smaller problem and try and solve that one.
好了,二分搜索也许是,最简单的分治算法,这意味着什么?,也就是说,为了解决一个问题,把它切割成小的问题,然后再来一个个解决。
Cutting involves enzymes called restriction endonucleases or restriction enzymes, which I've already mentioned and they have names.
切割用到的酶叫限制性核酸内切酶,或限制性内切酶,我已经提到过了,而且它们都有名字
He doesn't so much insist as you will see in your reading on the actual separation of functions of government putting them into separate hands.
但他其实并未坚持,如你们在阅读中会发现,政府的职权,是否真的分离,将权力切割开来。
It is both that which organizes a structure and that which isn't really qualified to organize anything, because it's not in the structure; it's outside the structure, something that imposes itself from without like a cookie cutter on the structure, right?
它既组织结构,又不真正地具有组织任何事物的资格,因为它不在结构之中,而是在结构之外,它将自己强加于结构之上,而不是像一个饼干成形切割刀一样,是吗?
In this case, this particular restriction enzyme cuts symmetrically like this, but not at the same point.
在我们这种情况下,这个限制性内切酶总是这样对称地切割,但两条链切割的位点不一样
And not just a camera but there are also tools on the end of these things so you can cut and you can do manipulations through this instrument.
除了摄像头外,在关节镜的末端还有其他的器械,你可以体外操纵这些器械进行切割等操作
That cutting is done by special proteins called restriction enzymes.
切割是由一种特别的蛋白质完成的,称为限制性内切酶
One way that you can look for that gene that you want is by making the cut in your plasmid inside of a gene that encodes for some property like resistance to an antibiotic.
一种找到成功重组质粒的方式,是在质粒控制某种特性的编码区域切割,例如,对抗生素的抗性
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
If this was a sickle patient, so they had this gene instead it wouldn't get cut and when I went to look for that presence of that gene on this gel, it would appear as one large segment instead of a large one and a smaller one.
而如果是个镰状红细胞贫血的病人,他们的基因是不会被限制酶切割的,因此他们基因的凝胶电泳结果就不会呈现,一大一小的结果,而只有一个大的片段
If you have DNA fragments, so this is DNA that you've cut up into fragments using restriction enzymes for example.
如果你有DNA片段,例如有一段你用限制酶,切割成片段的DNA
When it sees that sequence in a double stranded DNA it will bind there and it will cut.
当它在双链DNA中发现这个序列,就会与之结合并切割
Now another property of restriction enzymes is that they always cut the DNA in the same way.
限制性内切酶的另一个特性是,总是以同样的方式切割DNA
If I cut up just DNA from the chromosome, what's called genomic DNA, then I'm going to have both exons and introns within the fragments that I create.
如果我切割的恰好是染色体上的,基因组DNA,那我切成的片段上,就会同时有外显子和内含子
The first step is we had to be able to take this circular DNA and cut it to create a site for our new gene to be added.
第一步是切割环形DNA,以创造出一个整合新基因的位点
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
Restriction enzymes are just a kind of enzyme, enzymes are protein molecules that make a chemical reaction go faster, and the chemical reaction that restriction enzymes do is cutting DNA.
限制性内切酶是一种酶,而酶是加速化学反应的蛋白质分子,限制性内切酶加速的化学反应,是切割DNA
This gives you a biological mechanism for cutting, using restriction enzymes, and then you denature so that it falls apart, and then you renature so that it comes back together.
这是一种切割DNA的生物机制,用限制性内切酶,改变DNA的性质让它打开,然后让它合起来恢复它的性质
If I took this same restriction enzyme and tried to cut the chromosomal DNA of a sickle patient, it wouldn't cut at that point because the wrong sequence is there.
而如果我用同样的限制酶,去切割病人的染色体DNA,那该酶是不会起作用的,因为基因序列不对
If you cut and you open up a segment of DNA then you've left these sticky ends, for example and these sticky ends are capable of recognizing each other by the process of hybridization.
如果你进行切割打开一个DNA片段,就会留下,比如说,这些粘性末端,这些粘性末端能在杂交的过程中互相识别
There are hundreds,thousands of them known now, and each one has a specific character and one aspects of its character is that it only binds and cuts at a particular sequence of DNA.
已知的有成百上千种,每一种都有自己的特性,特性之一是,只结合和切割特定的某一种DNA序列
Well one way you could do it is by saying 'if I have this one base pair difference then this sequence is going to be cut by a specific restriction enzyme that recognizes the sequence CTGAGGA'.
一种方法是通过考虑,"如果我有这个不同的碱基对,那该序列必然会,被特定的限制酶识别并切割,这个特定的限制酶能识别,CTGAGGA "
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