Multivariate Cox regression analysis for 3-NT/Tyr and other selected possible predictors of mortality in patients with AKI.

Note: the multivariate analysis sequentially adjusted models for covariates as follows: Model 1, adjusted for age, gender; Model 2, adjusted for age, gender and APACHE II score; Model 3, adjusted for age, gender and sepsis; Model 4, adjusted for age, gender, APACHE II score and sepsis.