As of 1 April 2026, the PSJD database will become an archive and will no longer accept new data. Current publications from Polish scientific journals are available through the Library of Science: https://bibliotekanauki.pl
A modified method for chromosome preparation from bone marrow aspirates of normal individuals and leukaemic patiens is described for immediate clinical investigation. Hanks' balanced salt solution at different concentrations was used for in vitro incubation and hypotonic treatment. The method yields quite a high mitotic index with good metaphase spreads.