CJCP     2011 13 (11):  859-862    ISSN: 1008-8830  CN: 43-1301/R Factors influencing the bone mineral density in preterm infants YANG Wen-Xu, YANG Hui-Ming Department of Pediatrics, West China Second Hospital of Sichuan University, Chengdu 610041 China. yanghuiming03@163.com Received: null  Revised: null  Online: null Supporting info