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Gene Therapy Halts Vision Loss in Dogs Researchers have stopped vision decline in dogs with an inherited disease that causes blindness. The gene therapy technique they used may someday stop vision loss in humans. Retinitis pigmentosa (RP) is an eye d

发表于:2018-12-16 / 阅读(44) / 评论(0) 分类 VOA标准英语2012年(二月)

Sometimes it is hard to see the light, especially it lies in the invisible spectrum, like ultrared, ultraviolet radiation. But if you long to see the unseeable, you might interested to hear that under certain conditions people can catch a glimpse of

发表于:2018-12-24 / 阅读(35) / 评论(0) 分类 2015年Scientific American(一)月

[00:06.37]Some people cannot see all colors correctly. [00:10.92]They cannot see all the colors in a rainbow or a sunset. [00:16.40]They cannot tell if the meat they are cooking is done or if a fruit is ready to be eaten. [00:23.61]Poor color sight a

发表于:2018-12-26 / 阅读(35) / 评论(0) 分类 美国英语听力80篇

Night Vision And Humans: Why Cant We See Color? When we are in a fairly dark room, or outside at night away from lights, we can still see, but we cant see the colors of things very well. Why is that? There are two kinds of light-sensitive organs loca

发表于:2018-12-31 / 阅读(51) / 评论(0) 分类 英语听力文摘 English Digest

Sunscreened Plants 遮光植物 A NASA researcher is finding that alfalfa plants grow more poorly when exposed to UVB -- ultraviolet B radiation from the sun. Learn more about sunscreened plants -- today on Earth and Sky. JB: This is Earth and Sky. Eart

发表于:2019-01-02 / 阅读(104) / 评论(0) 分类 (科普英语)Earth and Sky

Cats And Colors You can look at that quilt your cat is curled up on and see a patchwork of greens, blues, and yellows. Your cat, however, cannot see color variation in the quilt. And here is why. Both humans and cats depend on the back layer of the e

发表于:2019-01-22 / 阅读(43) / 评论(0) 分类 英语时差8,16