1. Chemistry Research Laboratories, Dainippon Sumitomo Pharma Co., Ltd., Enoki 33-94, Suita, Osaka, 564-0053, Japan, Animal Health Products, Dainippon Sumitomo Pharma Co., Ltd., 5-51, Ebie 1-chome, Fukushima-ku, Osaka, 553-0001, Japan, and Pharmacology Research Laboratories, Dainippon Sumitomo Pharma Co., Ltd., 3-1-98, Kasugade Naka, Konohana-ku, Osaka, 554-0022, Japan