COVID-19(3) Pneumonia(2) Patient(2) mortality rate(2) COVID-19 prognosis(2) blood gas(2) onset of symptom(2) diagnosis of COVID-19(2) Hospitalized(2) male(2) endocan(2) early stage(2) venous blood(2) indicated(2) were measured(2) Endothelial dysfunction(2) Prognostic marker(2) severe pneumonia(2) Lactate(2) positive correlation(2) was determined(2) Prognosis(2) female(2) Follow-up(2) patients(2) Correlation analysis(2) the disease(2) Can(2) SARS-CoV-2(2) serum(2)