“…The systems of the body in normal condition have been studied for a long time, but in pathology their structure and behavior, as well as the properties and interaction of their elements, change in different ways in different nosological forms. Sometimes the very set of pathological processes is considered to be a system, since the processes are also related to each other [3]. In practice, first of all this is achieved, through a mathematical study of the relationships (correlations) between the measured parameters of the system as whole and its elements.…”