Electromagnetism, as one of the more mature disciplines in physics, has made great contributions to medicine. Every new discovery of electromagnetism or every new stage of technological development provides more advanced, more convenient and more precise instruments and methods for medical research and practice. It can be said that in modern medical research and medical units are inseparable from the electromagnetic methods and equipment.
First, the application of electromagnetism in medical equipment?Nuclear magnetic **** vibration tomography ?
Magnetic *** vibration tomography is a multi-parameter, multi-nuclear species of imaging technology. Currently the main hydrogen nucleus ( H ) density relaxation time T imaging. The basic principle is the use of a certain frequency of electromagnetic waves to the human body in the magnetic field of irradiation, the human body in a variety of different organizations of the hydrogen nucleus under the action of electromagnetic waves, nuclear magnetic **** vibration, absorption of electromagnetic energy, and then launched electromagnetic waves, MRI system detects these from the human body in the hydrogen nucleus launched out of the electromagnetic signals after the computer processing and image reconstruction, to get the tomographic image of the human body. As the hydrogen nucleus absorption and emission of electromagnetic waves, by the surrounding chemical environment, so by the magnetic **** vibration signals obtained by the human body tomographic images, not only can reflect the morphological information, but also from the image of the information related to pathology. After comparison and judgment it is possible to know whether the imaging part of the human tissue is normal or not. Therefore MRI is considered to be a medical imaging technology to study living tissues and diagnose early lesions. A new development in the application of MRI is that in addition to detecting lesions in human tissues, it can also detect a variety of functions in the human body, called functional MRI. For example, when the human brain is subjected to various external stimuli, it will cause changes in the blood composition, the amount of oxygen carried by the blood and the speed of blood flow, etc., and the hemoglobin in the blood is antimagnetic when it carries oxygen, and paramagnetic when it is deoxygenated, which causes changes in the image called NMR***Vibrational.
2. electrocardiogram ?
The electrocardiogram is a graphic recording of the changes in electrical activity produced by the heart with each cardiac cycle from the body surface using an electrocardiograph. In the resting state of a muscle cell, the cations arranged outside the membrane are positively charged, and the anions arranged in equal proportions inside the membrane are negatively charged, maintaining a balanced state of polarization and producing no change in potential. When the cell membrane at one end of the cell is stimulated, its permeability changes, so that the distribution of positive and negative ions inside and outside the cell is reversed, and the cell membrane at the stimulated site appears to be depolarized, so that the positive charge outside the membrane of the cell at that site disappears, while the cell membrane in front of it that has not yet been depolarized is still positively charged outside the cell membrane, thus forming a pair of electric couples. Power (positive charge) in the front, the electric hole (negative charge) in the back, the current from the electric depth into the electric hole, and along a certain direction of rapid expansion, until the entire cardiomyocyte depolarization is completed. At this time, the cardiomyocyte is positively charged inside the membrane and negatively charged outside the membrane, which is called the depolarized state. Subsequently, due to the metabolism of the cell, the cell membrane is gradually restored to the polarized state, this recovery process is called repolarization process, repolarization and depolarization successive procedures are the same, but the repolarization of the electric coupling is the electric acupuncture point in the front, the power supply in the back, and slower forward until the whole cell all repolarization.
3. Magnetoencephalography, magnetocardiography ?
The movement of electrons and ions is involved in many life activities. The movement of these charged particles creates an electric current, which in turn creates a magnetic field, which is called a biomagnetic field. For example, a beating heart produces a cardiac magnetic field; brain nerve activity produces a cerebral magnetic field; however, these biomagnetic fields are very weak. Taking human activities as an example, the human heart magnetic field is only about one millionth of the earth's magnetic field, and the human brain magnetic field and eye magnetic field are only about one billionth of the earth's magnetic field, and their strengths are also related to factors such as human health and diseases. The picture shows a magnetocardiogram and an electrocardiogram. It is important to note that since the human body's magnetic field, such as the heart's magnetic field, is much lower than the earth's magnetic field, extremely sensitive magnetometers are needed to measure weak magnetic fields, and large magnetic shielding chambers are needed to shield people from the effects of the earth's magnetic field. Since the measurement of the human body magnetic field is more complex and difficult than the measurement of the human body electric field, then why the study and application of the human body magnetogram? A large number of experiments show that compared with the human body electrogram, the human body magnetogram has more advantages. For example: the magnetic map can measure the human body's DC magnetic field and alternating magnetic field, while the electrogram can only measure the human body's alternating electric field; magnetic map measurements can leave the human body to do three-dimensional space measurements, the human body information obtained than the electrodes can not leave the human body and can only do two-dimensional space measurements of the electrogram measurements to obtain the confidence of the much more, and also do not have to use the electrodes produced by the contact and humidity and other issues of the interference of the impact of the many experiments also show that the magnetic map measurement resolution is also higher than that of the body. that the resolution of magnetographic measurements is also higher than that of electrogram measurements. Therefore, magnetoencephalography and magnetocardiography are more accurate and effective in medical diagnosis, but have not been widely used in clinical diagnosis for technical and price reasons. The understanding of lung magnetography is later, and it is more effective than X-ray in the diagnosis of lung diseases (such as pneumoconiosis). At present, some developed countries have taken it as an important means of diagnosis of lung diseases.4. Magnetic X-ray contrast agents?
Because the original X-ray contrast agent (barium meal) effect is not ideal, people developed a magnetic X-ray contrast agent, now used in clinical diagnosis. This is a kind of magnetic flow liquid, X-rays have a good absorption rate, by changing the external magnetic field, it can reach almost any part of the body to be examined, and will not be solidified in the body. 5. Electron microscope ?The electron microscope is widely used in medicine, and can be used to observe the fine structure that ordinary optical microscopes can not distinguish. Such as biological viruses, protein molecular structure. Electron microscope according to the principle of electron beam irradiation object well imaging, the use of electron beams through magnetic lenses (based on the magnetic focusing principle) for focusing, and then through the accelerating voltage can produce a very short wavelength of the electron wave, its magnification is dozens of times or even hundreds of thousands of times the ordinary optical microscope. ?
Two, electromagnetism in medical applications ?
1. magnetic therapy ?
In medicine, the use of electromagnetic principle can improve the microcirculation inside the human body to achieve the role of health care, such as blood circulation machine and various magnetic therapy instrument; according to the interaction between the human body and electromagnetic wave, in medicine, the use of electromagnetic energy
Thermal effect for high temperature treatment of tumors and general thermotherapy. Particle gas pedal is used in medicine to produce rays for diagnosis or treatment, can also be used to produce injected into the human body to facilitate the image of the radioactive material, it is the use of charged particles in the magnetic field made of the law of motion. Electromagnetism has been shown to be effective in reducing pain. Electromagnetism is effective in relieving pain, and magnetic therapy has become a pain relief remedy for many people. At present, magnetic therapy for pain relief is widely adopted by major hospitals in the United States outpatient clinics, and has become a popular special treatment method throughout the United States. Experts claim that magnetic therapy is not only effective in relieving pain, but also in treating the pain. Experts claim that magnetic therapy can not only reduce pain, but also fast repair of necrotic bone tissue, for many of the current medical profession recognized the hope of a cure for terminal illness.
2. Magnets ?Magnets generally refers to natural magnetite, magnetite's main chemical composition is iron tetraoxide, which in many cases has the ability to attract a strong magnetic material of special magnetic, known as permanent magnetism. It is because the magnet can attract in its near side of the strong magnetic material, as if the loving mother to get their children to the side, so the natural magnetite such as this is known as Ci Shi. ? Mentioning that magnets can be used in medicine to cure diseases seems incomprehensible to many people. In ancient China, there are many records of using magnets as medicines to cure diseases. In some medical books of various dynasties, you can find many records of applying magnets and other medicines to cure diseases. The famous pharmacologist Li Shizhen summarized the experience of his predecessors and personally practiced on the basis of a variety of applications of magnets and other strong magnetic substances in medicine for a very meaningful summary. Li Shizhen's "Compendium of Materia Medica" draws a picture of magnets as medicines, and the book says that when it comes to magnets as medicines, the odor of magnets is pungent, cold, and non-toxic; magnets are used to treat diseases such as rheumatism, pain in the limbs, deafness, and can also nourish the kidneys, strengthen the bones and bones, unclog the joints, and eliminate bloat; it can also cure sore throats, lumbar pains, dimming of the eyes, weakening of the tendons and bones, and the disease that the children accidentally swallowed the iron needles, restlessness, and five labors and seven injuries, and so on. . Speaking of the accompanying prescriptions for magnets, two methods of treating deafness diseases are enumerated. One method is to put a half-cent weight of magnet into the diseased ear, and then put powdered iron sand into the undiseased ear, and it will restore hearing to the diseased ear. Another method is to put the bean grains of magnets and by burning after the pangolin ground into powder together with new cotton wrapped up into the sick ear, and then in the mouth with a piece of raw iron, so that in the ear will be heard in the wind and rain like the sound, it will indicate that deafness disease has been cured. Magnet as a drug or a component of the drug, its application not only has a history of more than two thousand years, but also in the modern some important traditional Chinese medicine also has applications. Further research is still needed on the role of magnets on the human body and the mechanism of curing diseases, as with many other important...?
Three, electromagnetic waves in medicine?
1. X-rays?
(1).X-ray diagnosis ? X-rays are used in medical diagnosis, mainly based on the penetrating effect of X-rays, differential absorption, sensitization and fluorescence. As X-rays through the human body, by different degrees of absorption, such as the amount of X-rays absorbed by the bone than the amount absorbed by the muscle, then the amount of X-rays through the human body is not the same, so that it carries the density distribution of the human body parts of the information in the fluorescence screen or photographic film caused by fluorescence or photographic effect of the strength of the role of a greater difference, and therefore in the fluorescent screen or photographic film (after developing, fixing ) will show a different density of shadows. According to the contrast of shadow intensity, combined with clinical manifestations, laboratory results and pathological diagnosis, it can be judged whether a certain part of the human body is normal or not. Thus, X-ray diagnostic technology has become the world's first application of non-invasive visceral examination technology.
(2). X-ray therapy? X-rays are used in the treatment, mainly based on its biological effects, the application of different energy X-rays on the human body foci part of the cellular tissue irradiation, can be irradiated by the cellular tissue is destroyed or inhibited, so as to achieve the treatment of certain diseases, especially the purpose of the treatment of tumors. (3).X-ray protection?In the use of X-rays at the same time, it was found to lead to patient hair loss, skin burns, staff vision impairment, leukemia and other radiation damage, in order to prevent X-rays on the human body, must take appropriate protective measures. ? The above constitutes the application of X-rays in the medical aspects of the three links - diagnosis, treatment and protection.?
2. ultraviolet ? In the electromagnetic spectrum is located in the violet light and X-rays between the electromagnetic radiation. Wavelength of about (4 ~ 39) × 106 cm, can not cause visual (that is, outside the range of visible light). Substances through which visible light can pass are strongly absorbed by certain wavelengths of ultraviolet light. UV is commonly used in biology and medicine to sterilize and disinfect, induce mutations, and treat skin and cartilage diseases. UV also has physiological effects and is more useful in healthcare. UV light can also pass through the epidermis and cause chemical changes in the internal tissue cells of the body. Prolonged exposure to ultraviolet light will change the color of the skin, blood vessels will dilate, calcium and phosphorus in the blood will increase, red blood cells and blood pigments will also increase. In addition, it is also particularly suitable for the treatment of rickets, pediatric infirmity, tuberculosis outside the lungs and certain infectious skin diseases. 3. Infrared ? Infrared radiation on human skin, subcutaneous tissue has a strong penetrating power. External infrared radiation produced by the human body once the effect can make the skin and subcutaneous tissue temperature increases accordingly, promote blood circulation and metabolism, promote human health. Infrared physiotherapy on the organization of the thermal effect, anti-inflammatory effect and promote regeneration has been clinically affirmed, usually the treatment are used on the lesion site direct irradiation. Near-infrared micro-irradiation treatment on the microcirculation improvement effect is remarkable, especially the micro-blood flow state to improve the obvious. The performance of the irradiation of capillary blood flow speed up, red blood cell aggregation phenomenon to reduce the phenomenon of sub-papillary venous plexus bruising phenomenon reduced or disappeared, so as to improve the body's tissues, the important organs of nutrition, metabolism, repair and function of the body has a positive effect. 1 ~ 7μm infrared light waves can be transmitted through the skin to the cells, absorbed by protein molecules. This range of wavelengths of infrared light absorption can lead to protein molecules in the amide bond quantum vibration, which can make the smooth transfer of bioenergy from one place to another, so that the living body is in a normal state, to maintain the growth, development and health of the living body. The bioenergy to maintain the normal operation of the life system is provided by the hydrolysis of ATP, but once the ATP molecule or ATP enzyme (the hydrolysis of ATP requires the participation of enzymes) or water is insufficient, or the structure and conformation of proteins are altered or aberrated, etc., the bioenergy provided will not be sufficient to cause the normal vibration of the amide bond or the bioenergy cannot be transmitted normally. When biological tissues do not receive enough energy, they cannot grow normally and various diseases are induced. In this case, if infrared radiation with the above wavelength can be used and absorbed by proteins, the protein molecules can be restored to normal and the normal transmission of bioenergy, which may restore the biological tissues from the state of disease to the normal state and make the disease cured. ? Electromagnetism has a great influence on biomedicine, and our country is experiencing technological innovation. There is still a lot of way to go in the emerging industry in our country, and various cross-disciplines need to be closely integrated and constantly technological innovation.