1. Pharmacol.&Toxicol.Lab., Central Research Laboratories, Dong-Wha Pharm. Ind. Co., Anyang 430-017, Korea
2. Department of Biology, Faculty of Natural Science, Kyungsan University, Kyungsan, Kyungpook 712-240, Korea
3. Department of Histology, College of Veterinary Medicine, Kyungpook National University, Taegu 702-701, Korea