COVID‐19(22) therapy(22) MSC(21) MSCs(19) Cell(17) stem cell(17) acute respiratory distress(15) ARDS(15) tissue(14) syndrome(14) death(13) Treatment(13) pandemic(12) Mesenchymal stem cells(12) mesenchymal stem cell(11) COVID‐19(11) clinical trials(11) determine(10) Bone marrow(10) umbilical(10) adipose(10) COVID-19(10) clinical trial(10) acute respiratory distress syndrome(10) Effect(10) ACE2(9) SARS‐CoV‐2(9) virus(9) Efficacy(9) evaluate(9)