Application and effectiveness of an improved endoscopically guided nasojejunal tube placement technique in critically ill patients: a retrospective cohort study - Liang, Wei-Ling; Ma, Ming-Zhe; Min, Xiao-Hui; Ouyang, Xia; Liu, Jie; Wu, Hai-Hua; Zhan, Chun-Xia; Li, Xiao-Mei (Translational Gastroenterology and Hepatology, 2023)