单词：purine nucleotide
单词：purine nucleotide 相关文章
Worlds within Worlds First of all let us consider the earth (that is to say, the world) as a planet revolving round the sun. The earth is one of mine planets which move in orbit round the sun. These n
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The Dry Lands In most peoples minds the term desert conjures up an image of undulating sand dunes beneath the hot sun. There are, however, many other kinds of desert. Antarctica, Greenland and the polar ice packs are cold deserts where the water is l
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Also: Reduction in snow hurts Switzerland's winter-sports industry. Transcript of radio broadcast: 07 July 2008 VOICE ONE: This is SCIENCE IN THE NEWS in VOA Special English. I'm Steve Ember. VOICE TWO: And I'm Faith Lapidus. Hot weather has returne
VOA慢速英语2008年（七）月
AS IT IS 2015-07-12 Israel Helps California Deal with Water Shortages 以色列帮助加州对付水短缺问题 Israel knows how to deal with drought. The small Middle Eastern country has experienced dry weather conditions and water shortages for ma
2015年VOA慢速英语(七)月
Last October, a NASA rocket, traveling at a speed of 9,000 kilometers per hour, smashed into a dark crater on the moon's south pole. Upon impact, the Centaur rocket kicked up a cloud of debris and elements from the moon's surface, creating a so-calle
VOA标准英语2010年(十)月
I am a Hazara, and the homeland of my people is Afghanistan. Like hundreds of thousands of other Hazara kids, I was born in exile. The ongoing persecution and operation against the Hazaras forced my parents to leave Afghanistan. This persecution has
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