RT Journal Article SR Electronic T1 Association between angiotensin blockade and COVID-19 severity in Hong Kong JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E635 OP E635 DO 10.1503/cmaj.75865 VO 192 IS 23 A1 Ka Shing Cheung A1 Ivan F.N. Hung A1 Wai K. Leung YR 2020 UL http://www.cmaj.ca/content/192/23/E635.abstract