Fig. 5 The ion map for m/z 772, m/z 734 and m/z 744 obtained
from the slices of the spinal cord for norharmane matrix with the
different number of matrix layers (A) and four different heights of
spraying nozzle (B) for the positive ionization mode (matrix: 6 mg/ml
norharmane (chloroform:MeOH:H2O))