SSS 2011-03-22(在线收听) |
This is Scientific American’s 60-Second Science. I’m Cynthia Graber. This will just take a minute. X rays are so common today you probably never stop to think about them. They help check a broken wrist, a sprained ankle, the state of our teeth. But a little more than a century ago, x ray machines provided a revolution in medicine, allowing doctors to look inside the body. And now scientists in the Netherlands have gotten a chance to look at how the original technology functioned. A first-generation anatomical imaging x ray machine was built in the Netherlands in early 1896. Advances to the technology came quickly, and that first machine was relegated to an old warehouse. Then a year ago, a Dutch radiologist got his hands on the machine and dusted it off. He and a colleague tested it using a cadaver hand. They published their research in the journal Radiology. They found that an x ray image that requires just 21 milliseconds today would have taken 90 minutes in 1896. And the radiation exposure would have been 1,500 times greater than modern technology’s. Early x ray operators and researchers thus often suffered burns and other maladies. The scientists wrote that the images they produced with the ancient machine were severely blurred—but still awe-inspiring. Thanks for the minute. For Scientific American’s 60-Second Science, I’m Cynthia Graber. |
原文地址:http://www.tingroom.com/lesson/sasss/2011/3/143921.html |