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{{B}}New Attempts to Eradicate AIDS
Virus{{/B}} A high-profile attempt to eradicate the AIDS virus in a few patients continues to show promise. But researchers won’t know for a year or more whether it will work, scientist David Ho told journalists this Wednesday for the Fourth Conference in Viruses and Infections. "This is a study that’s in progress," says Ho, head of the Aaron Diamond AIDS Research Center, New York. The study involves 20 people who started combinations of anti-HIV drugs very early in the course of the disease, within 90 days of their infections. They’ve been treated for up to 18 months. Four others have dropped out because of side effects or problems complying with the exacting drug system. The drugs have knocked the AIDS virus down to undetectable levels in the b A. continues to be hopeful B. will be successful in a year C. will be successful in future D. will stop being hopeful 更多"{{B}}第三篇{{/B}}"的相关试题: [单项选择]第三篇
Water
The second most important constituent (构成成份) of the biosphere (生物圈) is liquid water. This can only exist in a very narrow range of temperatures, since water freezes at 0℃ and boils at 100℃. Life as we know it would only be possible on the surface of a planet which had temperatures somewhere within this narrow range.
The earth’s supply of water probably remains fairly constant in quantity. The total quantity of water is not known very accurately, but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers. Most of it is in the form of the salt water of the oceans about 97 percent. The rest is fresh, but three quarters of this is in the form of ice at the Poles and on mountains, and cannot be used by living systems until melted. Of the remaining fractional which is somewhat less than one per cent of the whole, there is 10—20 times as much stored underground water as t
A. in the center of the earth. B. on the surface of our planet. C. in a very narrow range of temperatures. D. in the coastal areas of the earth. [单项选择]{{B}}第三篇{{/B}}
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