Can Opium Use Contribute to a Higher Risk of Colorectal Cancers? A Matched Case-control Study in Iran oleh Ahmad NAGHIBZADEH-TAHAMI, Vahid YAZDI FEYZABADI, Narges KHANJANI, Ahad ASHRAFI-ASGARABAD, Hosniyeh ALIZAEH, Vahid Reza BORHANINEJAD, Mohammad MORADI-JOO, Masoud ZEINALI, Mohammad Javad ZAHEDI, Mahmoud AGHAEE-AFSHAR, Ali Akbar HAGHDOOST