Factual abstract knowledge of biochemistry can be used in different fields of clinical medicine. It is well known that bones, cartilage, intervertabral disks (ID), vertebras, skin, vessels, cardiac valves and other organs include connective tissue (CT).It is characterized by the fact that it does not have many cells (only 1-9% from tissue weight). It has much extracellular matrix (EM).EM contains collagenic and uncollagenic proteins as well as complexes of proteins and carbohydrates. We call them proteoglycans (PG). In the PG-composition there are special carbohydrates - glycosaminoglycans (GAG). Chondroitinsulfates (Ch-S) are one of the 7 types of GAG. Hydroxyproline (HP) is the specific molecular marker of collagen. Tyrozine (Tyr) is the specific molecular marker of uncollagenic proteins. When the destruction of CT occurs the chemical components come into blood. When CT is repaired the content of CT-macromolecules comes to the norm. In case of vertebral disease that is called osteochondrosis (OCh) the change in chemical composition occurs and as a result the biomechanical properties of one or some IDs change. In this case the ID does not play the role of a spring and the nerves are nipped and the ache appears. In the 1960s OCh was treated by the injection of plant enzyme, papaine, to destruct the defected disk and to form strong commissure between the vertebras. Biochemical reaction to the treatment was the change in the concentration of Ch-S in blood, namely the increase in its content. It was clinically stated the higher the level of Ch-S concentration was, the greater the effect of OCh treatment. It has also been revealed that the increase in the Ch-S concentration in the blood shows the formation of CT-rib in myocard that is the sign of the reparation of the acute myocardial infarction (AMI).Thus, it should be noted that the change of Ch-S content in blood helps us to monitor the level of AMI healing. The correlation between HP and Tyr in the tumor tissues in the patients having ovarian cancer (OC) gives us the prognosis of the disease. If the above coefficient is more then 150% as compared to healthy tissues it means that CT stromal component in the tumor exceeds parenchyma and the prognosis is good. In this case fibrous tissue will develop in the place of tumor ectomy. The list of biochemical results useful for medicine can be continued and we see in that the magical power of science.