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1.
During the last three decades the interest toward clinical application of magnetic and electromagnetic stimulation increased worldwide. Numerous publications have discussed the possibility of exogenous magnetic fields to initiate beneficial effects on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields are increasingly utilized for the treatment of numerous musculoskeletal injuries and pathologies. For example, selected magnetic fields were reported to be beneficial in the treatment of musculoskeletal injuries and post-surgical, post traumatic and chronic wounds, reduction of edema, in the acceleration of pain and stress relief, and thus contribute to healing processes. The application of this modality could be facilitated by establishing the exact dosimetry of application and by searching for biophysical mechanisms of action, as well. It should be remembered that “not all magnets are equal”, therefore the specific medical problem requires a proper diagnostics, a selection of the magnetic field to be applied and a design of the appropriate protocol for treatment. The paper advised that every study and report should carefully explain both the medical problem and the parameters of the applied magnetic field and cautions against generalized statements like “Magnetic field does/does not cause biological response”.  相似文献   

2.
Magnetic and electromagnetic fields are now recognized by the 21st century medicine as real physical entities that promise the healing of various health problems, even when conventional medicine has failed. Today magnetotherapy provides a non-invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of diseases and pathologies. Millions of people worldwide have received help in treatment of musculoskeletal system, as well as pain relief. Pulsed electromagnetic fields are one important modality in magnetotherapy and recent technological innovations, such as Curatron pulsed electromagnetic field devices, offer excellent, state of the art computer controlled therapy system. In this article the development, state of the art and future of pulsed electromagnetic field therapy are discussed.  相似文献   

3.
Summary Despite of decades of successful worldwide use of magnetic/electromagnetic field therapy, the answer to the question of possible mechanisms of action is still lacking. Scientific reports of successful therapeutic use of magnetic/electromagnetic fields are worldwide; however, our understanding of the underlying mechanism is limited. This paper presents a new hypothesis that therapeutic benefit of magnetic fields might result from effects that originated on the level of important systems in human body. It is known now that the life is an electromagnetic event in aqueous medium. Therefore, an appropriate choice of magnetic and/or electromagnetic field may be expected to initiate systemic changes that result in efficacious effects distant from the point of application. Observations of this phenomenon have been reported in at least two forms: (1) neutralization of the pain experience distant to the point of magnetic field exposure; and, (2) various alterations of T-lymphocytes in response to pain and to magnetic fields. Extrapolating these observations to the level of blood-vessel system, one might hypothesize that a “healthy” cell does not respond as readily to the applied fields as do abnormal cells (which are in a disease or injury state).  相似文献   

4.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli. Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most) sensitive indicators to detect and quantify physiological effects of electromagnetic fields.  相似文献   

5.
Natural and man-made magnetic and electromagnetic fields are important factors in the contemporary life. The paper discusses the role of environmental magnetic and electromagnetic fields in origin and evolution of life. A brief review of the characteristics of Earth magnetic field, Earth magnetosphere, and their role as a shield for cosmic radiation follows. The role of endogenous and exogenous magnetic fields is discussed in respect of the clarification of the potential hazard and benefit of electromagnetic fields. The second part of the paper discusses the mechanisms of detection and response to exogenous electromagnetic fields, as well as threshold versus window hypothesis for mechanisms of interactions. Finally, the necessity of accurate dosimetry at the target site and the importance of relevant research and clinical protocols in studying biological responses are pointed out.  相似文献   

6.
The study and observation of electromagnetic phenomena have followed the evolution of human thought from the dawn of civilization to the present day; also magnetotherapy has followed a similar path. Magnetotherapy has been applied and continues to be applied in many branches and fields of medicine, as it accelerates the healing of fractures, has analgesic and anti-inflammatory properties that can help in inflammatory or degenerative diseases of bones, joints and the peripheral nervous system, and stimulates the healing of open skin lesions (such as bed sores, diabetic ulcers) etc. If magnetotherapy has so many fields of application in medicine, we may therefore ask why doubts, prejudice and limitations to its therapeutic use still exist. This brief historical excursion wants to give a small contribution to answer the question.  相似文献   

7.
The use of magnetic fields (MFs), in general, and electromagnetic fields (EMFs), in specific, as therapeutic modalities is becoming very common. In the USA, EMFs are mostly used in orthopedics, followed by pain relief and the wound-healing arena. Even though a substantial literature exists worldwide, we are still lacking the accepted comprehensive mechanism(s) of action. In general, it is thought that the best therapeutic effects are achieved when the stimulation is applied directly to the target area. Since the beginning of this century, however, more and more evidence has been collected indicating that effects of the MF stimulation may also be observed at site(s) different from the site of application of the signal. A primary purpose of this paper is to propose a link between the systemic and direct effects. The functional units known as trigger points are discussed as possible “doors” allowing the stimulation to be delivered to the target tissue/organ. A second purpose is to suggest some possible modes of action.  相似文献   

8.
Occupational exposure to radiofrequency (RF) and static magnetic fields at magnetic resonance imaging (MRI) suites is of continuing concern to personnel who routinely work in this environment. Questions regarding the levels of occupational RF and static field exposure have increased with the increasing demand for anesthetics to be administered in this environment. The present study was thus designed towards addressing the above-mentioned problem by gaining information regarding exposure levels of clinical personnel at MRI units in South Africa. Three 1.5 MRI units in Bloemfontein, South Africa were utilized to evaluate the exposure of clinical personnel to the electromagnetic fields present in the MRI environment over a period of time and during different clinical MRI procedures. Three rounds of measurements of RF fields in the MRI environment were done. All the three measurement rounds were focused on the low frequencies, 5 Hz–32 kHz, as well as on the high frequencies, 300 kHz–40 GHz. First round measurements were done to establish the background of the RF fields in and around the magnet room during an MRI examination. Second round RF field measurements were done at a specific location, 1 m away from the bore on the right-hand side of the bed, in the MRI room. The third round measurements were of the same format as the second round, but the specific location was against the magnet bore. Two pieces of Narda Safety Test Solution instruments, the EFA-300 and EMR-300, were used to measure the electromagnetic and magnetic exposure fields generated from the MRI scanners. Results of the measurements indicate that the electromagnetic fields measured during different clinical procedures do not exceed the International Commission on Non-Ionizing Radiation Protection (2000) guidelines in these units. Results from round two and three showed that the RF and gradient exposure 1 m and up against the bore entrance does not exceed these guidelines (rms average over 6 min). Ongoing new developments in MRI scanning create the need for continuously monitoring exposure of patients and workers to the EMF fields in the MRI environment.  相似文献   

9.
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however, when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal. Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally, this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction.  相似文献   

10.
Experimentally induced acute inflammation in rats is a good model system which includes the complexity and dynamics of the processes; moreover there are many defined markers for following and estimating changes in an observed system. In this paper, we discuss an in vivo model of acute inflammation induced by carrageenan. Carrageenan-induced paw edema is a model of non-infectious acute inflammatory reaction to assess the contribution of mediators involved in vascular changes associated with acute inflammation and potential treatments. A complex approach into the investigation of possible effects of static magnetic fields (SMF) action on experimentally induced acute inflammation in rats (by measurements of the levels of specific stress markers) is very important in understanding the possible inflammatory mitigation effects, pain relief, and oxidative stress state of an organism. This approach could help for better understanding of the possible mechanisms of interaction of dynamic processes such as inflammation healing and pain relief with external SMF (25 mT at 10, 20 and 30 min exposure time). Results indicate that SMF with B = 25 mT for 30 min diminished the inflammatory process and decreased the levels of inflammatory markers (fibrinogen) and stress markers (ACTH, Cor) into the blood plasma in rats as when compared with sham exposed animals. The exact mechanism by which SMF contributes to the acceleration of inflammatory healing and decrease of inflammation markers in blood plasma in rats still remains unclear. We assume that two possible mechanisms exist. One is the direct interaction of SMF with free active oxygen forms (free radicals) affected by their membrane processes and related with the physiological functions. Another possible mechanism might be related to dynamic regulation of inflammation healing process.  相似文献   

11.
The 21st century medicine is characterized with increasing variety of diagnostic and therapeutic devices that implement magnetic and electromagnetic fields most of which utilize time varying signals. In many cases, however, these devices are used without proper knowledge of the physical parameters of the applied signals. In an attempt to facilitate the use of magnetotherapeutic devices, the basic principles of physical and biophysical dosimetry in clinical settings are discussed in this article.  相似文献   

12.
Summary In an effort to explain the benefit of therapeutic use of electromagnetic fields (EMF) a systemic effect has been proposed by us. To assess the efficacy of this approach, an objective biochemical approach was developed. Ten patients with Reflex Sympathetic Dystrophy (RSD) were clinically evaluated, and lymphocytes were isolated from their blood samples obtained before and after exposure of the uninvolved limb to an EMF. Utilizing a SpectraCell method that includes radio labeled molecules and protein-free media for culturing the lymphocytes, an elevation of the content of fructose, serine, glycine, and calcium cellular metabolic uptake were found following in the culture to EMF in comparison with non-exposed lymphocytes (p < 0.01). In addition, the pain level was determined by a conventional visual analogue scale (VAS) before and after EMF exposure, evidencing a significant pain relief. Specifically, after exposure to 120 pps semi sinewave, 1500Gauss EMF, generated by a THERAMAGledR device, an improvement in the flexibility of the limb and a reduction in swelling of the affected extremity were detected clinically. These findings are in concert with the new hypothesis that, with relief of pain, lymphocytes are predominately altered in their cell cycle from M phase to S phases associated with increased structuring of intracellular water. A consideration of the basic understanding of the role lymphocytes may be inferred from this preliminary study. An extensive review of the literature on the basic science and therapeutic use of magnetic fields in humans is provided in an attempt to understand the relevance of magnetic therapy of specific pain syndromes.  相似文献   

13.
Our research involves determining how non-invasive electric and magnetic fields influence neuronal growth in vitro. In previous studies we have shown that pulsed electromagnetic fields (PEMF) as well as direct current (DC) alone stimulate neurite outgrowth from dorsal root ganglion explants [Sisken et al. 1984; Sisken et al. (Restor Neurol Neurosci 1:303–309, 1990); Greenebaum et al. (Bioelectromagnetics 17:293–302, 1996)]. A maximum response was obtained when nerve growth factor (NGF) was also present in the medium. The results of our experiments using static magnetic fields of different strengths are presented below and indicate that fields of high magnetic strength (450–900 gauss) with added NGF stimulate neurite outgrowth comparable to the response obtained with PEMF plus NGF.  相似文献   

14.
The utility and the safety of the extremely low frequencies (ELF) electromagnetic fields in the treatment of numerous diseases have been demonstrated. Moreover, the effects of these fields seem to depend on their respective codes (frequency, intensity, waveform). We want to value the effects and the safety of the therapeutic application of a musically modulated electromagnetic field (TAMMEF) system, which field is piloted by a musical signal and its parameters (frequency, intensity, waveform) are modified in time, randomly varying within the respective ranges, so that all possible codes can occur during a single application. Sixty subjects, affected by shoulder periarthritis were enrolled in the study and randomly divided into three groups of 20 patients each: the first exposed to TAMMEF, the second exposed to ELF, the third exposed to a simulated field. All subjects underwent a cycle of 15 daily sessions of 30 min each and a clinical examination upon enrolment, after 7 days of therapy, at the end of the cycle and at a follow-up 30 days later. All the patients of TAMMEF group and ELF group completed the therapy without the appearance of side effects: they presented a significant improvement of the subjective pain and the functional limitation, which remained stable at the follow-up examination. In those exposed to a simulated field group, there was no improvement of the pain symptoms or articular functionality. This study suggests that the TAMMEF system is efficacious and safe in the control of pain symptoms and in the reduction of functional limitation in patients with shoulder periarthritis. Moreover, the effects of the TAMMEF system cover those produced by the ELF field.  相似文献   

15.
Numerous studies have demonstrated the utility of extremely low frequencies (ELF) electromagnetic fields in the treatment of pain. Moreover, the effects of these fields seems to depend on their respective codes. In our study we want to value the effects and the safety of the TAMMEF (Therapeutic Application of a Musically Modulated Electromagnetic Field) system, which field is piloted by a musical signal and its parameters are modified in time, randomly varying within the respective ranges, so that all possible codes can occur during a single application. Ninety subjects, affected by chronic low back pain, were enrolled in the study and randomly divided into three groups of 30 patients each: A exposed to TAMMEF, B exposed to ELF, C exposed to a simulated field. All subjects underwent a cycle of 15 daily sessions of 30 minutes each and a clinical examination upon enrolment, after 7 days of therapy, at the end of the cycle and at a follow-up 30 days later. All the patients of groups A and B completed the therapy without the appearance of side effects: they presented a significant improvement of the subjective pain and the functional limitation, which remained stable at the follow-up examination. In group C, there was no improvement of the pain symptoms or articular functionality. This study suggests that the TAMMEF system is efficacious and safe in the treatment of patients with chronic low back pain.  相似文献   

16.
Osteoarthritis (OA) is a chronic degenerative condition involving the joints caused by metabolic changes in chondrocytes metabolism. Treatment with magnetic fields (EMFs) produces benefits to patients affected by this pathology. The present research has the aim to investigate, by a proteomic approach, the effect of magnetic fields on cultured chondrocytes, because EMFs interferes greatly with OA chondrocytes metabolism. Human osteoarthritic chondrocytes were obtained from the femur head of osteoarthritis adult patients and were cultured under standard conditions and exposed for precise times both to extremely low-frequency (ELF; 100-Hz) electromagnetic fields and to the Therapeutic Application of Musically Modulated Electromagnetic Fields (TAMMEF), which are characterized by variable frequencies, intensities, and wave shapes. We tested the effects of the different exposure by 2-DE analysis and demonstrated that chondrocytes metabolism was highly influenced by the treatment with EMFs; in fact many proteins change their expression after the stimulation, but differently, depending on whether we use ELF or TAMMEF system.  相似文献   

17.
Electromagnetic fields exposure assessment methodology is briefly presented. The basic problems defined for the practical use of electromagnetic fields measurements and numerical calculations carried out for workers exposure assessment in real occupational situations are discussed. The examples of data from real workplace are presented, focusing: spatial distribution of electromagnetic fields affecting worker’s body, complex characteristics of the frequency content, workers activities/moving in the workplace, field impedance, etc. The situation when the use of calculations is required is discussed. The basic requirements for workers exposure assessment protocols are presented. The possible range of the use of internal and external measures of exposure level is also discussed.  相似文献   

18.
Over the last years, a wide debate has developed on the possible health effects of exposure to electromagnetic fields. In-depth research activity was therefore developed by the international scientific community aimed at evaluating the risk associated with exposure to this type of radiation. At the same time, various international institutions began to issue recommendations on exposure limits valid for workers and for the population in the frequency range up to 300 GHz. Most of the recently revised safety standards worldwide are set in terms of internal rates of electromagnetic energy deposition (Specific Absorption Rate) at radiofrequency and microwave frequencies, and of induced electric fields or current densities at lower frequencies up to 10 MHz. At the international level, the most authoritative guidelines have been developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP); another internationally well recognized standard is that developed by the Institute of Electrical and Electronics Engineers (IEEE) in the USA, adopting the same basic approach of ICNIRP, although with some differences in numerical values. This article is mainly focused on the analysis of different approaches for the protection against electromagnetic fields, and on the rationale of most relevant standards.  相似文献   

19.
Summary Since IARC classified ELF magnetic field as Possibly Carcinogenic to Human the fear from 50/60 Hz magnetic field exposure had been increased to the state of public “panic”. Subsequently, environment quality preservation organizations increased their pressure on their government to adopt the “precautionary principle” and to reduce the allowable ELF Magnetic Field exposure to much lower values than are recommended by ICNIRP-1998. As an example the present Environmental Ministry in Israel recommendation is to lower the ELF Field exposure to 10 mG averaged over 24 h. As a result of this stringent exposure guideline imposed by the government, electrical engineers who are involved in the deployment and installation of large and medium electrical utilities, such as overhead power lines, transformers, UPS systems, electrical public transportation, switching stations, etc., are much more aware to the need to employ special measures and methods for reducing the magnetic fields that might be emitted from such utilities. There are few computer codes that are capable of analyzing with great accuracy magnetic and electric fields surrounding single phase and three phase electrical utilities in a 3-D system. The best presentations of the analysis results are by equi-value contours depicting electric and magnetic fields. This graphical presentation is a powerful design tool that enables better deployment and installation design aided to reduce the magnetic field emissions from high-power electrical utilities. This paper describes the various types of graphical presentations available for ELF field contours, the dependent and independent variants and parameters, magnetic field animation for optimization of power line installation and routing, and finally an example that demonstrates the usefulness of the graphical presentation tools.  相似文献   

20.
The field of bioelectromagnetics, consisting of the study of the interaction between electromagnetic fields and biological systems, has been rapidly expanding in the recent years. One important factor that contributes importantly to the development of this field is the continuing advances in technology allowing researchers to investigate different endpoints, or to more precisely measure changes, if any. Hybrid functional imaging is a rapidly maturing field that opens new, important horizons for bioelectromagnetics research. Indeed, unraveling the interaction mechanisms of electromagnetic fields on biological systems (with an emphasis on the brain) requires a monitoring of electrical, functional, and metabolic activity of living tissue at different temporal and spatial scales. Individual tools (e.g., electroencephalography, EEG; functional magnetic resonance imaging, fMRI) are limited in their ability to detect the effects of electromagnetic interaction at specific temporal and spatial scales, so combining these imaging methods offers a unique opportunity to provide a more comprehensive view of effects in living tissue. In this paper, we will present the different imaging techniques that are available to bioelectromagnetics researchers, including their capabilities and how they are complemented by simultaneous hybrid imaging. Future possibilities of hybrid imaging technologies are discussed.  相似文献   

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