1. Laboratory of Internal Medicine II, School of Veterinary Medicine, Azabu University, 1–17–71 Fuchinobe, Chuoku, Sagamihara, Kanagawa 252–5201, Japan
2. Research Institute of Biosciences, School of Veterinary Medicine, Azabu University, 1–17–71 Fuchinobe, Chuoku, Sagamihara, Kanagawa 252–5201, Japan