title: [Variability of the heart rhythm during mental work of varying intensity].
mesh_terms: D000328:Adult; D004562:Electrocardiography; D006339:Heart Rate; D006801:Humans; D005222:Mental Fatigue / Q000503:physiopathology; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D011674:Pulse; D011890:Railroads; D013315:Stress, Psychological / Q000503:physiopathology*; D014586:USSR
vernacular_title: Variabel'nost' serdechnogo ritma pri umstvennoĭ rabote raznoĭ napriazhennosti.