TY - JOUR AN - 7 AU - Otori,K. AU - Oda,Y. AU - Sugiyama,K. TI - High frequency of K-ras mutations in human colorectal hyperplastic polyps. JO - Gut PY - 1997 VL - 40 SP - 660-663 M2 - 660 DO - 10.1136/gut.40.5.660 ER -