Characterization of LC-MS based urine metabolomics in healthy children and adults oleh Xiaoyan Liu, Xiaoyi Tian, Shi Qinghong, Haidan Sun, Li Jing, Xiaoyue Tang, Zhengguang Guo, Ying Liu, Yan Wang, Jie Ma, Ren Na, Chengyan He, Wenqi Song, Wei Sun