CJCP     2021 23 (6):  569-574    ISSN: 1008-8830  CN: 43-1301/R Risk factors for the first ventilator weaning failure in preterm infants receiving invasive mechanical ventilation LIU Xiao-Yi, TONG Xiao-Mei Department of Neonatology, Peking University Third Hospital, Beijing 100191, China Received: 2021-03-12  Revised: 2021-04-14  Online: null Supporting info