Inverse ratio between bacilli and cocci, the number of bacteria decrease were associated with kinds and treatment course of antimicrobial application, but fungus infection had no relation with kinds and treatment course of antimicrobial application.

• 粪便杆菌和球菌比例倒置、细菌计数减少与抗菌药物应用种数及疗程相关；真菌感染与用药种数及疗程无相关性。