当前的方法使用病毒或者化学物质向细胞中引入外来dna，但是这些操作将带来永久性的改变，会引起其特有的并发症。
Current methods use viruses or chemicals to bring foreign DNA inside cells, but these make permanent changes, which could have their own complications.
虽然吸取移民是唯一的可以阻止欧洲人口缩减的方法，但是流入的外来移民不会对年龄结构产生很大的改变。
And although migration is the only thing which prevents many European populations from shrinking, an influx of outsiders will not change age-structures by much.
那坏消息就是，由于所有的限制，对与外来人没有什么方法能够兑现索赔。
The bad news is that with all the restrictions, there are few ways for outsiders actually to cash in on the claim.
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