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***System analysis is the classification of system sub-goals, into which its main general goal is divided.***
Quotations from the book Gaides MA General theory of systems.
"This makes it possible to evaluate systems. The sufficiency or insufficiency of the interaction of the elements of the system is determined by the correspondence between the result of the action of the system (the actual value) and its purpose (the proper value). If the system can fulfill its intended goal - it is sufficient, if not - it is not enough."
"In the annex to medicine, this sounds like this. If the interaction of the systems (subsystems) of the body is sufficient to fulfill the goal (given function - the proper value), then regardless of the strength of the reaction - it's just a reaction of the body, not a disease. If the interaction of the elements is not sufficient to achieve the goal, then the reaction is inadequate and pathological, because the body systems can not perform what is required of them, they are overloaded and this leads to the destruction of their elements, to a decrease in the functions of the systems and to their inadequacy to perform the prescribed goals. But the destroyed element is not a disease, but a system defect. The process of destruction of elements and accumulation of defects is a disease. Ie, the result of the action of the body systems can be either a normal reaction, or pathological. In the latter case, it can be either based on a defect in the body's system, or on the basis of a disease."
"Deterministic (cause-effect) mathematical models are the main analytical tool of system analysis (mathematical modeling). An example of deterministic mathematical models in technology is, for example, ballistics - the science of flying a body in a medium and a gravitational field. The hit of the abandoned body in the target can also be estimated with the help of a statistical mathematical model: for example, the probability of the body falling into the target is 80%. But if we know the weight of the body, the strength of the angle and direction of the throw, as well as many other additional parameters, such as the viscosity of the air, the direction of the wind, etc., and we have an exact ballistic formula (deterministic mathematical model) falling of a body. This model is based on the use of artillery, missile launches, criminology, etc."
"An example of deterministic mathematical models in medicine is, for example, Fick's formula - the dependence of the delivery of oxygen in the tissue from the oxygen capacity of the blood and cardiac output. By this formula, it is possible to calculate accurately the values ​​of cardiac output of the left ventricle and the accuracy will depend only on the accuracy of the measurement of the initial parameters. The determinateness of the formula consists in the rigid and unambiguous dependence of each parameter of the formula on its other parameters.
The purposefulness of systems plays a decisive role in the analysis of systems of a living organism. For example, in the circulatory system there is a subsystem (system) of stabilizing blood pressure, which has a quite definite goal - to maintain blood pressure at a given level. The goal for this subsystem is the circulatory system (the neural centers of the circulatory system are located in the medulla oblongata). The purpose of the circulatory system is to distribute the blood flow to all tissue regions of the body, and this is due to a certain balance between the vascular resistance of the microcirculatory zone of various tissue regions, cardiac output, and the volume of circulating blood. Arterial pressure is the resultant function of these three arguments. If the circulatory system has "decided" that it is necessary to maintain high blood pressure (arterial hypertension), it will set this goal for stabilizing blood pressure, which will "try" to do this. The human body is governed by the laws of automation. And the automation always tries to keep the set value of the parameter, even if something knocks it down. If we "interfere" with her medical activities, she eventually finds workarounds and the old medications cease to have an effect. Therefore, we constantly have to change the treatment.
Arterial hypertension is not a disease, but is a syndrome that accompanies a large group of different normal and pathological states of the body. The physiological basis of this syndrome is general hypervolemia (fluid overflow of the vascular bed), an increase in the total peripheral vascular resistance, and a change in the ratio between cardiac output and total peripheral vascular resistance. Depending on what factor prevails and under what conditions, this syndrome can be a normal or pathological reaction of the cardiovascular system to the normal or abnormal state of any other conjugated systems, for example, muscle, or urinary.
At healthy and athletes at the peak of the load there is a significant increase in blood pressure, but this is not hypertension! Nobody will give an athlete an anti-hypertensive treatment only because at his peak the blood pressure rises to 270 mm Hg."