The researchers looked an aggressive form of Simian Immunodeficiency Virus that up to 100 times more deadly than HIV while infected monkeys usually die within two years, the scientists have developed the vaccine that can stop the virus from taking hold. After inoculating rhesus macaque monkeys, the US team then exposed them to SIV, they found that at first the infection began to establish and spread._______________________________ 研究人员观察的这种侵入式猿猴免疫病毒,其致命程度是HIV病毒的100倍,通常受到感染的猴子在两年内就会死亡.科学家们研制出的疫苗可阻止病毒存活.美国研究小组在给恒河猴注射疫苗后,将它们置于猿猴免疫病毒环境中,小组成员发现,病毒最初稳定并有扩散迹象,_______________________________