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　　So mang people use the cell phone so frequantly every day,But ___47__little is certain adout he health effects of its use.Macufacturers___48___that cell phones meet government standards for safe radio-frequency radiation omission,but enough studies are beginning to document a possible ___49___in rare brain tumour(肿瘤)：bendaches and behavioral disorders in children to cause coneem.So far,the avidence isn't___50___on whether the use of cell phones __51__to any uncased risk of cancer.In a new
trial,researchers asked 47 yolunteers to ___52__in a project to measure glucose(葡萄糖)consurnption in the brain by scanning the brain to see how cells use energy.For both 50-minute scans,the volunteers had a cell phone __53__to each ear.During be first scan,the devices were turned off,but for the second scan,the phone on the right ear as___54____on and received a recorded-message call,although the yolume was muted(消毒)so the dise wouldn't bias the results.The results of the second scan abowed that the__55__of the brain rarest to the device had higher rales of glucose consumption than the rest of the brain.The study ows that cell phones can change brain activity,and __56__a whole new avenue for scientific quiry,tuough it doesn't say anything about whether cell-phone radiation can cause cancer.
　　注意：此部分试题请在答题卡2上作答。
　　A)conclusive 　　I)mission
　　B)contributes 　 J)participate
　　C)derive　　　　 K)particular
　　D)expresses 　　L)provides
　　E)fixed 　　　　　M)regions
　　F)immensely 　　N)surprisingly
　　G)increase 　　　O)switched
　　H)maintain

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