1. Department of Parasitology and Tropical Medicine, and Institute of Endemic Disease, Seoul National University College of Medicine, Seoul 110-799, Korea.
2. Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
3. Department of Parasitology, College of Medicine, Yanbian University, Yanji, Jilin Province 133000, P.R. China.