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Anna D. Kostadinova
St. Ivan Rilski University Hospital, Internal department, Medical University, Sofia, Bulgaria
Marian Y. Mihaylov
St. Ivan Rilski University Hospital, Internal department, Medical University, Sofia, Bulgaria
Irena D. Ivanova
St. Ivan Rilski University Hospital, Department of clinical laboratory and immunology, Sofia, Bulgaria
Rayna T. Robeva
St. Ivan Rilski University Hospital, Internal department, Medical University, Sofia, Bulgaria