【英语时差8,16】移除大肠毒素分子(在线收听) |
It's three in the morning and you're awakened out of a deep sleep by a terrible pain in the gut. Was it something you ate? And then it hits you--that burger you had the other day was a little undercooked. And there have been several cases of e-coli poisoning reported in your area. If you do have e-coli toxins coursing through your bloodstream, the symptoms can be distressing, particularly the bloody diarrhea. And, unfortunately, there's no antidote. All you can do is wait it out. But that may change. Scientists at the University of Alberta, in Canada, have engineered a molecule to seek out e-coli toxins in the blood and flush them out of the system. The molecule works like a kind of molecular barb: it cruises around in the blood, and when it finds an e-coli toxin it snags the toxin and attaches it to an immune system protein. The protein then neutralizes the toxin. So far the molecule has been tested in mice and been found to be effective. But because e-coli poisoning is relatively rare, it's unlikely that the molecule will be used to manufacture a marketable drug any time soon. The research is still useful, though, because it models a promising way to treat a potentially wide range of bacterial infections. For example, the e-coli toxin is shaped similarly to the cholera toxin. So there could be a molecular solution to treating cholera--a disease that affects millions of people around the world. |
原文地址:http://www.tingroom.com/lesson/englishtimeover/341357.html |