1. Institute of Cardiological Research, Saratov State Medical University, B. Kazachaya str., 112, Saratov 410012, Russia
2. Institute of Physics, Saratov State University, Astrakhanskaya str., 83, Saratov 410012, Russia
3. National Medical Research Center for Therapy and Preventive Medicine, 10, Petroverigsky per., Moscow 101953, Russia