4Lieberman DA, Weiss DG; Veterans Mfairs Cooperative Study Group 380. One-time screening for eolorectal cancer with com- bined fecal occult blood testing and examination of the distal co- lon[J]. N Engl J Med,2001,345(8):555.
5Van Rossum LG,van Rijn AF,van Oijen MG,et al. False negative fecal occult blood tests due to delayed sample return in colorectal cancer screening[J]. Int J Cancer, 2009,125 : 746.
6Wilcox CM,Alexander LN,Cotsonis G.A Prospective characteriza-tion of gastrointestinal hemorrhage presenting with hematochemia[J].AmJ Gastroenterd, 1997,92(2):231-235.