MOLECULAR EPIDEMIOLOGICAL INVESTIGATION ON CO-INFECTION OF INTESTINAL PROTOZOA IN GASTROINTESTINAL CANCER PATIENTS Journal title: Acta Parasitologica et Medica Entomologica Sinica Authors: Nan ZHANG, Hong-bo ZHANG, Xiu-yan YU, Yan-hui YU, Peng-tao GONG, Jian-hua LI, Xiao-cen WANG, Xin LI,... Subject(s): Biological Sciences