[Chronobiology and practical medicine]

In present time, to classify the healthy as potencional possibility of the organism to accept variable environment influences without the break of the biological important functions is not satisfactory. Examples from the different field of the clinical medicine refer to importance of the knowledge's of the circadian rhythmicity concerning many diseases, symptoms or significant remissions. Therefore, clinical trials considering the biological variability differ from the convectional studies by assumption that biology of patient is dynamic, that time of the diagnostic test running is significant and that drugs can influence safety and therapeutic effect in the dependence on the day-time. In paper, it is showed on some examples from the clinical practice that respection of the chronobiological principles may play the important role in the medical diagnostics as well as in therapy and may improve accuracy of the whatever functional examination. For terms, which are often used in the chronobiological texts, no suitable terms were available and therefore it was necessary to introduce the descriptive phrases, which would be accepted by specialists in the field. Many of the introduced terms are still unknown to many investigators and physicians who might benefit from the application of chronobiologic principles to their work.