Figure 1

Scatter plot of plasma BDNF levels with the number of years of heroin use.
(A) Representative linear regression of plasma BDNF levels with the number of years of heroin use. (B) Representative plasma BDNF levels with the number of years of heroin use. Patients were divided into 3 three groups: ≤5 years, 6–15 years, ≥16 years.