RT Journal Article SR Electronic T1 Proton pump inhibitors and the risk of severe COVID-19: a post-hoc analysis from the Korean nationwide cohort JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 2013 OP 2015 DO 10.1136/gutjnl-2020-323672 VO 70 IS 10 A1 Seung Won Lee A1 Jee Myung Yang A1 In Kyung Yoo A1 Sung Yong Moon A1 Eun Kyo Ha A1 Abdullah Özgür Yeniova A1 Joo Young Cho A1 Min Seo Kim A1 Jae Il Shin A1 Dong Keon Yon YR 2021 UL http://gut.bmj.com/content/70/10/2013.abstract AB