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[科技前沿] 【整理】2010-02-28&03-03 手心大小的癌症检测装置

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[Homework]【整理】2010-02-28&03-03 手心大小的癌症检测装置

HW
Now from the Boston Museum of Science, Sci-tech Today, on NECN.
--Sci-tech Today. The device that could make the cancer testing more available world-wide. It's called Nuclear Magnetic Resonance System and it's actually been ran for decades. So what's new, a Harvard researcher has found a way to shrink it from 250 pounds to this device which weighs less than a quarter of a pound. Nano technology correspondent Alex join us live, from the museum of science in Boston. Welcome Alex, how could this device help find cancer?
--Well, Chad, this is the device that detects cancer in the blood. So tumors release certain markers into the blood and by detecting them, we can do a much better job of diagnosing and monitering cancer. Uh, so unfortunately the techniques we used to do these tests can be pretty inconvenient. So they often involve a laboratory equipment that's very expensive and isn't available to everyone. So for today, what we're looking at is a different way of testing blood for cancer called Nuclear Magnetic Rsonance or NMR. And basically what NMR use is, it's like MIR scan. Except it scan the whole body, you only scan a tiny sample of someone's blood.
--All right. So this is based on an MIR scan, but those aren't exactly cheap or convenient. How is this NMR different?
--Well, in many cases they are actually not that much different. So I have a picture here of an actual commercial an NMR machine. And you can see, that is a pretty bulky device and also it's quiet expensive, so this  really doesn't help make this testing more available to people. Uh, however, uh, so, so, we are talking back here is a scientist's name, &&&&&, who's an electronic engineer from Harvard University. And, &&& saw that real problem with this big MRI devices was the giant magnet inside them. So, there are 2 main components that every NMR machine: a magnet which pours on your blood sample with the magnetic field, and a transceiver which examines the sample and receives the back signal to detect what is in the sample. So, normally, the magnet is by far the biggest and the most expensive piece of the MIR machine, and so a real MIR magnet would be many many times bigger than this, and it would weigh hundreds of pounds. But, &&& and his advisor Don realized that this expensive magnet really won't necessary, a tiny magnet would work just as well. You just need the other component, the transceiver, to be sensitive enough. So &&& went to work on this, he's an electronic engineer, so he completely redesign the MIR's transceiver. And within a few months he created this, which is basically the same device, it got magnet and transceiver. But this is 1,200 times smaller, 150 times more sensitive, and 4,000 times cheaper than the commercial MIR machine.
--Well, that's pretty amazing, so it just rework in the transceivevr that allowed it to  shrink that device down to what you just showed us.
--Yeah, pardon me, Chad.
--No, go ahead.
--I was just goona say that so shrink it down was a huge part of what made this possible, but also  Doc. uh, excuse me, &&& borrowed a technique from other researchers at Harvard. And that was to add magnetic nano particle to blood samples, so it explains why exactly he wanna do that. Let's take a look at this model I have right here: so imagine that this red area is your blood sample, and you add to it these magnetic nano particles, although in reality the magetic nano particles are hundreds of thousands of times smaller than this. But, if there is no evidence of cancer in your blood sample, then the nano particles just scan it around; but if you do have a cancer marker presence in your blood, then the nano particles are tracked to it, they stick to it and they form a cluster around it, this cluster is very very easy to detect using MIR. So, what we done here is make this test much more sensitive. Instend of trying to find this one little cancer marker, you're able to find the big magnetic cluster that's surrounding it.
--All right, Alex, that's a fascinating stuff. Alex, thanks for joining us live today from the museum of science.
--Thanks for having me, Chad.

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