Objective To investigate the riskfactorsfor development of melanosis coli.

目的:探讨结肠黑变病的相关致病因素.

Objective:To investigate the pathogenic factors of colon melanosis and its outcome.

目的：探讨结肠黑变病的致病因素及转归。

Objective: To investigate the pathogenic factors of colon melanosis and its outcome.

目的：探讨结肠黑变病的致病因素及转归。