Usually it's done by taking all or part of the infectious agent, and showing them to your immune system in some way.

通常它会带着全部或部分抗原介质,并以某种方式呈递给你的免疫系统

耶鲁公开课 - 生物医学工程探索课程节选

This was my first glance at plum pudding, and I guess you can see that this must be that positive part -- most of the plums are within that, and you can see all these little raisins or plums in here, that would be that negative charge.

我想你们可以，看到着一定是正电部分,大部分的李子,都在这里面，你们也可以看到,这些小的葡萄干或李子，这就是负电荷。

麻省理工公开课 - 化学原理课程节选

And I can obviously do the other direction which is I can say skip to index 2 and all the remaining pieces. This lets me slice out, if you like, the front part or back part or a middle part of the tuple as I go along.

很明显我可以从索引2开始切片,所有剩下的元素，这可以让我2,如果你喜欢我这么说的话,取得元素的前面的或者后面的,或者中间的部分。

麻省理工公开课 - 计算机科学及编程导论课程节选