Possible reason:Cells are adhered together

Recommended solution:Shorten the digesting time

Possible reason:Cells are seriously fragmented

Recommended solution:Too many necrotic areas in the sample, the section thickness is inaccurate, and the time for the digestion step is too long 

Possible reason:The outlines of cells are not clear, or cloud-like matter covers the cells 

Recommended solution:The time for the digestion step is too short

Possible reason:Improper glass slides are used

Recommended solution:Use the positively charged glass slides 

Possible reason:The glass slide is baked incorrectly

Recommended solution:Check the temperature of the slide warmer

Possible reason:Pretreatment and denaturation are excessive 

Recommended solution:Shorten the pretreatment and denaturation time