Figure 4. A, An unbiased counting frame laid on the image of the sections to estimate the numerical density (Nv) of the fibroblasts. The nuclei are unclear at the first 5 µm optical section (height of dissector). B, As above, any nucleus which lies in the counting frame or touches the inclusion borders (dotted lines), does not touch the exclusion borders (continuous lines), and comes into the maximal focus within the next traveling 5 µm optical section (height of Dissector) are counted (the two arrows, Hedenhain’s azan stain × 2000).