METHODS: Keloids and normal skins(negative controls) were obtained from 6 patients and 6 normal people who operated in the Department of Plastic Surgery, Peking University Third Hospital.
方法：瘢痕疙瘩和正常皮肤（作为阴性对照）均来自北京大学第三医院成形科手术患者各6例。
2
Plans, organises, directs, controls and coordinates a primary health organisation that provides a broad range of out-of-hospital health services.
初级卫生机构管理者负责企划、组织、指导、控制和协调初级卫生机构，提供大范围的院外医疗服务。
3
The incidence of complications following endoscopy was decreased as compared to the controls, so was the decline of days of hospital stay and medical expense.