1. Blood Diseases Diagnostic UnitLaboratory of Haematopathology and Immunology, National Specialised Hospital for Active Treatment of Haematological Diseases, Sofia 1756, Bulgaria
2. Blood Diseases Diagnostic UnitLaboratory of Cytogenetics and Molecular Biology, National Specialised Hospital for Active Treatment of Haematological Diseases, Sofia 1756, Bulgaria
3. Department of Clinical HaematologyNational Specialised Hospital for Active Treatment of Haematological Diseases, Sofia 1756, Bulgaria
4. Laboratory for Experimental ChemotherapyMedical University of Sofia, Sofia 1000, Bulgaria