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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Periodic acid schiff stain shows block positivity with following cell line:
assistant
The correct answer is  Leukemic lymphoblasts react with periodic acid schiff (PAS) stain gives reddish-purple clumps, sometimes more rectangular in character and referred to as "block" positivity (as opposed to the fine granular staining that can be seen in some myeloblasts and other cells). Ref: Lichtman M.A., Shafer J.A., Felgar R.E., Wang N. (2007). G. Lymphocytic Leukemias. In M.A. Lichtman, J.A. Shafer, R.E. Felgar, N. Wang (Eds), Lichtman's Atlas of Hematology.