1. Department of Laboratory Service; Senriyama Hospital; Toyonaka Osaka 560 Japan
2. Department of Life Science; Kyoto University of Education; Kyoto Kyoto 612 Japan
3. Department of Preventive Medicine; Kyoto Prefectural University of Medicine; Kyoto Kyoto 602 Japan
4. Department of Zoology, Faculty of Science; Kyoto University; Kyoto Kyoto 606 Japan