Robert,
This usually happens to lymphoid tissue. It is from freezing it. We had run 
into this problem many times and now trim and soak block in soapy solution or 
ammonia solution very dilute with cold water. Blocks usually cut nicely 
after. 
Do not pick up first 3 or for sections on ribbon. This has worked for us. 
Hope it works for you.
RetTek2000

<< ---------
 > From:    SALA,ROBERT[SMTP:SALAR@siouxvalley.org]
 > Sent:    Friday, March 17, 2000 10:34 AM
 > To:  'HistoNet'
 > Subject:     Nuclear Staining
 > 
 > Please forgive me if I am going over old discussions.
 > 
 > We are having a problem with our nuclear staining.  It especially occurs
 > on
 > tiny biopsies and on lymphoid tissue.  It is that hazy washed out nuclear
 > pattern.  We have tried about everything to correct the problem.  One our
 > paths is adamant that it is a heat artifact, I am leaning to incomplete
 > dehydration.  We have no heat above 63 C. in any of our procedure, we
 > dehydrate in ethanol and clear in a xylene substitute called Clear-Rite
 > III.
 > This artifact in intermittent and does not affect all tissues on the run.
 > It appears to get worse towards the bottom of the slides.  VERY
 > FRUSTRATING!
 > 
 > If anyone has any suggestions on how to correct this please let me know.
 > Thanks everyone.
 > 
 > 
 > Robert M. Sala M.T.(ASCP)
 > Histology Supervisor
 > Sioux Valley Hospital
 > 1100 S. Euclid Ave.
 > Sioux Falls, SD  57117-5039
 > 
  >>