<正> IntroductionCurrently,there are at least 850,000 peo-ple living with human immuno-deficiency virus(HIV) and acquired immuno-deficiency syn-drome (AIDS) in China.Among them 16-29years old account for about 65%.Accordingto the Chinese health authorities,if the pre-ventive measures are not effective,the figurecould reach as many as 10 million by the year2010.Since there are currently no cure or