6Hellman CA. Respiratory syncytial and parainfluenza viruses [J ]. J Infect Dis, 1990; 161 (3): 402~406
7Mcintosh EDG,Silva LMD, Oates RK. Clinical severity of respiratory syncytial virus group A and B infection in sydney, australia[J].Pediatr Infect Dis J, 1993; 12(10) :815~819
8McConnochie KM , Roghrmann KJ. Bronchiolitis as a possible cause of wheezing in childhood: new evidence[J ]. Pediatrics , 1984; 74(1):1~10