1 A. Tsyb Medical Radiological Research Center - branch of the National Medical Research Radiological Center of the Ministry of Health of the Russian Federation, Obninsk, Russia.
2 Federal State Autonomous Educational Institution of Higher Education ''People's Friendship University of Russia'', Medical Institution, Moscow, Russia.
3 A. Tsyb Medical Radiological Research Center - branch of the National Medical Research Radiological Center of the Ministry of Health of the Russian Federation, Obninsk, Russia; Federal State Autonomous Educational Institution of Higher Education ''People's Friendship University of Russia'', Medical Institution, Moscow, Russia. Electronic address: dr_gordon@yahoo.com.