Fig. 1From: Rationale and design of REGULATE: an observational study protocol for relationship between plasma metabolome and the efficacy of systemic glucocorticoid in acute exacerbation of chronic obstructive pulmonary diseaseFlow chart of REGULATE study. AECOPD: acute exacerbation of chronic obstructive pulmonary disease; BGAV: a scoring system for AECOPD patients, B: bronchodilator; G: glucocorticoid; A: antibiotic; V: ventilation;Back to article page