³í¹®) Cumulative Dose Threshold for the Chemopreventive Effect of Aspirin Against Gastric Cancer ¼¿ï´ëº´¿ø °¡Á¤ÀÇÇаú ¹Ú»ó¹Î ±³¼ö(»çÁø)ÆÀ(1ÀúÀÚ ±è¹ÎÇü ¿¬±¸¿ø)