Methods Ambulatory 24 h esophageal pH monitoring was performed in 36 NCCP cases ( patient group ) with recurrent chest pain and without respiratory diseases and musculoskeletal abnormalities in chest, and 20 of them underwent gastric endoscopy. 方法对36例(病例组)诊断为NCCP并排除呼吸系统和胸部肌肉骨骼病变患儿进行24h食管pH值监测,其中20例行胃镜检查。