1. T. Shirakawa and J. M. Hopkin, Lung Research Laboratory, Osler Chest Unit, Churchill Hospital, Oxford OX3 7LJ, UK.
2. T. Enomoto, Department of Otolaryngology, Japanese Red Cross Society, Wakayama Medical Center, Wakayama, Japan.
3. S. Shimazu, Department of Pediatrics, National Waka-yama Hospital, Wakayama, Japan.