Figure 2.

OPLS-DA scatter plot generated from ¹H nuclear magnetic resonance spectra of plasma from patients with chronic obstructive pulmonary disease with abnormal Savda syndrome (gray circles) and healthy controls (black squares). The model parameters were R²X[1]=0.153587, R²X[2]=0.230561, R²Y=0.83 and Q²=0.68. OPLS-DA, orthogonal projection to latent structure-discriminate analysis. t[1]P, the principal component of the three-dimensional figure; Num, the percentage of the principal component.