1. Department of Histology, Cytology and Embryology, Kazan State Medical University, Kazan 420012, Russia
2. Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan 420008, Russia
3. Asklepios-Med (Private Medical Practice and Research Center), H-6722 Szeged, Hungary
4. Tokaj-Hegyalja University, H-3910 Tokaj, Hungary