Relationship between fetal cardiac axis angle and congenital heart defects in the second trimester of pregnancy
Su Fangfei, Wang Jingjing, Yin Chenghong, Yue Wentao, Wu Qingqing
Journal of Capital Medical University . 2019, (6): 838 -841 .  DOI: 10.3969/j.issn.1006-7795.2019.06.006