Scientists Seek HIV Vaccine Using Monkey Model Traditional vaccine methods have been unsuccessful in preventing infection by HIV, the virus that causes AIDS. New techniques are being studied to boost antibodies or other parts of the immune system. Bu

发表于:2019-01-13 / 阅读(33) / 评论(0) 分类 VOA标准英语2012年(九月)

Voice 1 Welcome to Spotlight. Im Mike Procter. Voice 2 And Im Liz Waid. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live. Voice 1 Todays Spotlight program is about

发表于:2019-01-19 / 阅读(30) / 评论(0) 分类 环球英语 Spotlight

There was no way she could come to terms with death; she lay night after night in a confused terror, trying to imagine if death was perpetual night, or an abyss of flames she had to jump over to reach the golden fields on the far side, or a sphere li

发表于:2019-01-29 / 阅读(54) / 评论(0) 分类 荆棘鸟

By Lisa Schlein Geneva 24 December 2007 The World Health Organization says the most infectious type of polio could be eradicated worldwide by next year, leaving only one more strain of the disease to be tackled. WHO, which began its global polio erad

发表于:2019-01-31 / 阅读(36) / 评论(0) 分类 VOA常速英语2007年(十二月)

The second type of vaccine contains an attenuated virus. This virus is alive, but has been grown in the lab for several generations, so it isnt able to multiply very well in humans. With the attenuated virus multiplying very slowly, your body is able

发表于:2019-02-15 / 阅读(40) / 评论(0) 分类 英语时差8,16

How vain and foolish, then, thought I, 于是,我心里想, for timid untravelled man to try to comprehend aright this wondrous whale, by merely poring over his dead attenuated skeleton, stretched in this peaceful wood. 那些足不出户的胆小鬼

发表于:2019-02-17 / 阅读(44) / 评论(0) 分类 白鲸记