Research methods in pathophysiology

2021-04-26 03:29 PM

Scientific experiments often build experimental models on animals from clinical observations to support the proposed hypotheses.

GS. Thomas "Experiment on animals and observing in patients is the basic method of pathophysiology". Experimental methods in Medicine, developed and summarized by Claude Bernard nearly 200 years ago, have helped medical researchers in general and the pathophysiology, in particular, an important weapon in research. The purpose of experimental medicine is to detect the operating rules of the diseased body through experimental models on animals.

The experimental method is a research method that derives from objective observation from natural phenomena (pathological phenomena occurring), and then uses previous knowledge to try to explain them (called a hypothesis); Then use one or more experiments to prove the correct or false hypothesis (can be experimented on animal models).

Steps of empirical research

Figure: Diagram of research in pathophysiology.

Observe and hypothesize

Before a pathological phenomenon, whether it is a traditional medicine or modern medicine, people observe and comment on pathological phenomena. After observing (subjectively or objectively), people seek to interpret and explain what observed. Observers can detect the same thing at the same time, but can also be different; can also explain differently the same phenomenon they observe; However, the above explanations are subjective to human beings, depending on the philosophical point of view of the observer, the contents of explanation are also different (idealistic, materialistic, dialectical or metaphysical), depending on each period of the development of medicine, but the meaning also changed.

From observation, Hypocrate (500 years BC) has stated that: clear nasal fluid is secreted by the brain; shows cold body conditions; red blood secreted by the heart, indicating a hot condition; black blood secreted by the spleen, showing a moist state; and gold bile secreted by the liver, indicating a dry state. All diseases occur due to the imbalance of the above 4 fluids.

The experimental method by Claude Bernarde asked the scientist.

Observe carefully and objectively. The more truthful the information, the easier it is for the hypothesis to be closer to the truth.

When explaining, the more using the existing theoretical results, the more opportunities for a hypothesis to approach the truth.

Today, it is necessary to pay attention to the achievements of many different sciences, and depending on the specific conditions that apply accordingly. Patients come to physicians with symptoms that need to be detected by all means objectively. First the physician must use his five senses to observe; then combine with the means of subclinical techniques to increase the detection of phenomena that cannot be observed by humans. Paraclinical tests and functional exploration give more objective, accurate and sensitive results than what the physician himself receives with his five senses, but those techniques are also made by humans. so they must be subject to the rules and conditions of performance to be reliable enough.

After having all the information in the patient, the physician formed in his mind a certain pattern of pathology. Also, compare this model with other models (gained through learning and experience) to see which model it is most like and the most suitable diagnostic direction. Thus, the diagnosis is only a hypothesis that the physician makes based on the objective observations obtained.

Prove the hypothesis by experiment

This is a mandatory step, but Traditional Medicine did not have the conditions to perform, but just stopped at step 1, that is to observe; then explain after trying to apply your "Medicine" in practice.

Scientific experiments often build experimental models on animals from clinical observations to support the proposed hypotheses. These experiments are conducted actively at the stage or stage, giving vivid pathological images in experimental time. Experiments can be performed on each organization, on each isolated organ and on the whole body; or combined with each other and carried out in vivo (in vivo) or in vitro (in vitro).

If the diagnosis is correct, you can decide on the appropriate treatment and cure. Thus treatment is also empirical evidence. It should be noted that this evidence has its own conditions. For example, the body's resistance is necessary for self-healing, supporting the physician as well as treating and making the process of self-healing faster. There are also diseases, though diagnosed, science is currently not cured. In the end, if the disease is too severe, the treatment is not suitable, the patient's death and the method of dissecting the body and diagnosing biopsy is very valuable experimental evidence.

To get results requires the right methods, Claude Bernard: "Only good methods will allow us to develop and make better use of the abilities that nature offers us". In order to do so, there must be accurate and objective clinical comments; propose correct and scientific hypotheses; find suitable experimental methods to prove the appropriateness between clinical reality and stated hypothesis; From there, the most general rules of the disease are drawn and finally, it is widely and effectively applied in practice (for disease prevention and treatment).

Applying experimental methods in clinical practice

A physician is a scientist, the examination process to detect the right disease is like the truth discovery process, which means that the above steps are followed. Diagnosis is actually the application of steps of experimental methods to increase the ability to find the truth. The behaviour and virtues of the physician, in this case, are still meticulous, accurate, and honest.



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