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1.
Marko S. Markov 《The Environmentalist》2007,27(4):457-463
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications
discussed the possibility exogenous magnetic and electromagnetic fields to initiate 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 treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries
and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration
of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique
in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical
mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs
to be developed in parallel with clinical applications. 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 injury. Unfortunately, there are many obstacles
that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of
magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for
tissue repair are subjects of this review. 相似文献
2.
Marko S. Markov 《The Environmentalist》2009,29(2):169-176
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
3.
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
4.
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
5.
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
THERAMAG∘ledR 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
6.
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
7.
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
8.
Marko S. Markov 《The Environmentalist》2007,27(4):465-475
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
9.
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
10.
The health care staff operating magnetic resonance imaging (MRI) scanners are exposed to static magnetic field of significant
spatial heterogenity and high level of flux density—usually existing permanently during the shift. The personnel can also
be exposed to pulses of magnetic field of high rate of rise/fall, so-called gradient fields, which exist only during examination
of patients. The level of workers’ exposure depends both on the type of the magnet and on the ergonomical characteristic of
design of the particular MRI scanner. This paper presents the current state of the art on occupational exposure to static
magnetic field health effects, gaps in scientific data, MRI workers’ exposure characteristics, research needs, and suggestions
for the exposure assessment protocol for future investigations. 相似文献
11.
Antonietta Albanese E. Battisti G. Pompella A. Ghezzi A. Vittoria G. L. Messa A. L. Pasqui G. Campoccia L. Bianciardi N. Giordano G. Galassi 《The Environmentalist》2009,29(2):196-199
In our paper we studied the effects of exposure to ELF (extremely low frequency) or musically generated TAMMEF (therapeutic
application of musically modulated electromagnetic fields) electromagnetic fields on the tumor necrosis factor alpha (TNF-α)
release induced by a lipopolysaccharide (LPS) from cultured human lymphomonocytes of peripheral blood. Lymphomonocytes, isolated
from blood donors buffy-coat, were prepared using standard techniques in cell culture flasks, kept in CO2 incubator, with controlled temperature and humidity for 5 days. Flasks were subjected to an ELF electromagnetic field (100 Hz
sinusoidal) or to TAMMEF electromagnetic fields (with intensity, frequency, and wave shape randomly modified in time, so that
all possible codes can occur during a single application). The TNF-α release was determined by ELISA test every 24 h for 92 h
and the results were evaluated by a non-parametric test. LPS induces a stronger TNF-α release in cultures that were subjected
to ELF when compared with cultures subjected to TAMMEF, at each time period of the experimental protocol. These results seem
to indicate that TAMMEF is able to induce a complex modulation of LPS-induced TNF-α release, a cytokine with pro inflammatory
property whose release during chronic or neoplastic inflammatory diseases has strong negative effects on several organ systems. 相似文献
12.
Increased knowledge of the magnetic field influence on hemodynamic function may have significant therapeutic potential and
possible health effects. For example, magnetic field therapy using moderate intensity static magnetic fields (SMF) in the
mT range (in particular, 1–600 mT) could be useful for circulatory diseases, including ischemic pain, inflammation, and hypertension,
primarily due to the modulation of blood flow and/or blood pressure through the nervous system. We suggested that the mechanisms
of SMF effects on the circulatory system in the mT range could be mediated by suppressing or enhancing the action of biochemical
effectors, thereby inducing homeostatic effects biphasically. The potent mechanisms of SMF effects have often been linked
to nitric oxide pathway, Ca2+-dependent pathway, sympathetic nervous system (e.g., BRS and the action of sympathetic agonists or antagonists), and neurohumoral
regulatory system (e.g., production and secretion of angiotensin II and aldosterone). Thus, this review mainly focuses on
the experimental studies of SMF effects on the circulatory system in animals and may provide the physiological basis for future
clinical investigations of SMF therapy. 相似文献
13.
Marko S. Markov 《The Environmentalist》2011,31(2):89-96
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
14.
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
15.
Epidemiological studies suggesting the possibility of harmful effects on human (specifically children’s leukaemia) due to
long-term exposure to magnetic fields of extremely low frequency (e.g. 50/60 Hz) and relatively low values (i.e. over the
microtesla range) have stirred high activity in the topic of magnetic field mitigation. To reduce these fields, it is common
to use passive metal screens (e.g. plates made of aluminium or steel). To design them, effective and fast numerical computations
are highly desirable. In this article, a method is presented, which computes various parameters of screens in a given shielding
problem and yields magnetic field distribution and shielding factors. The method takes into consideration the 3D field distribution
and is able to solve systems with large aspect ratios (thin thickness in comparison with its other dimensions); this is a
common problem where other methods such as finite elements often experience difficulties. The presented method computes separately
the field inside and outside the screens. Afterwards, the solutions are “stitched” together along the border of the subregions.
Two practical examples are given of the developed numerical method. 相似文献
16.
E. Battisti A. Albanese L. Bianciardi A. I. Fiaschi M. Rigato A. Vittoria G. L. Messa N. Giordano 《The Environmentalist》2009,29(2):190-195
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
17.
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
18.
Chiyoji Ohkubo Hideyuki Okano Akira Ushiyama Hiroshi Masuda 《The Environmentalist》2007,27(4):395-402
Authors review the importance of studying the effects of electromagnetic fields (EMF) on microcirculatory system, especially
in respect of possibility that vasculature may have direct and indirect role in interaction of static magnetic fields (SMF).
We outline the physiological importance of microcirculation and relatively new methods of evaluation technique in vivo and
explain in details the local and/or whole body exposure effects of SMF with␣range of 0.3–180 mT, power frequency EMF with
range of 0.1–30 mT and microwaves at 1.5 GHz with range 0.08–8 W/kg brain average specific absorption rate (SAR) on microcirculatory
systems in different tissues in experimental animals. 相似文献
19.
Henrietta Nittby Arne Brun Susanne Str?mblad Mehri Kaviani Moghadam Wenjun Sun Lars Malmgren Jacob Eberhardt Bertil R. Persson Leif G. Salford 《The Environmentalist》2011,31(2):140-148
Since the late 1980s, our group has examined the effects of radiofrequency electromagnetic fields (RF-EMF), including pulse-modulated waves of the type emitted by mobile phones, upon the blood?Cbrain barrier. In more than 2,000 rats, we have repeatedly demonstrated a passage of the rats?? own albumin from the blood through the brain capillaries into the surrounding brain parenchyma at SAR values down to 0.1mW/kg. In most of these experiments, the animals were exposed in TEM-cells, ventilated by an external electrical fan at 50 Hz. In the present study, we examined whether the extremely low frequency (ELF) magnetic fields from the fan (50 Hz, 0.3?C1.5 ??T) might add to the RF effect. Sixty-four rats were divided into 4 groups: RF only, ELF only and RF + ELF exposure plus a sham group. The GSM-900 MHz RF exposure was at the very low, nonthermal, average whole-body SAR level 0.4 mW/kg. Demonstration of the normally occurring albumin extravasation in the basal hypothalamus is our inbuilt control proving that the staining is reliable. Two full series of staining of the whole material gave negative results for hypothalamus. Not until we changed to avidin, biotin, and antibodies from a third supplier, we received an acceptable staining. Twenty-five percent of the RF animals had a pathological albumin leakage, while the ELF and RF + ELF groups with three and two pathological findings, respectively, were not significantly different from the control group. We conclude that the use of external fans has had no major influence upon the result. 相似文献
20.
Martino Grandolfo 《The Environmentalist》2009,29(2):109-117
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