Patient:I bleed quite a bit when I have a bowel movement .I ’ m really worried about it .患者:我大便时出了不少血,我真担忧。患者:鲜红色的。医生:血和大便混在一起?Doctor:Do you have constipation often ?医生:你经常便秘吗?Doctor:Have there been any change in the pattern of your feces ?医生:粪便形态有变化吗?医生: ......