[1] CENT RES INST TAKARA SHUZO,OTSU 52021,JAPAN
[2] OSAKA BIOSCI INST,SUITA,OSAKA 565,JAPAN
[3] KYOTO UNIV,INST VIRUS RES,KYOTO 606,JAPAN
[4] KYOTO INST TECHNOL,DEPT BIOTECHNOL,KYOTO 606,JAPAN
[5] OSAKA UNIV,MICROBIAL DIS RES INST,DEPT VIROL,SUITA,OSAKA 565,JAPAN