Fig. 1From: Evaluation of serum amino acids and non-enzymatic antioxidants in drug-naïve first-episode major depressive disorderChanges in serum levels of amino acids (μmol/L) in the study population. Boxplot showing the median, maximum, and minimum value range. a Methionine, b Phenylalanine, c Tryptophan, d Tyrosine are lower in the patient group. Mann-Whitney U test was performed to present p valuesBack to article page