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1.
The contingency of the variations in the amplitude frequency parameters of the main modes of extremely-low-frequency resonances ionosphere waveguide (Shuman resonances) and changes in the parameters of human electroencephalograms in the range of the frequency "window" (6-16 Hz) was studied. The results of studies in the regimes of synchronized monitoring suggest that the contingency of the parameters of electroencephalograms and extremely-low-frequency resonances, expressed in the parameters of the cross-correlation function, is statistically significant and varies from 0.12 to 0.65 at alpha = 0.95. It was found that the magnitude of contingency is largely the function of the current value of the solar and geomagnetic activity.  相似文献   

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Potential effects of extremely low frequency (ELF) electromagnetic fields on periphyton were studied from 1983 to 1993 using a Before, After, Control and Impact design. The study was conducted at two sites on the Ford River, a fourth-order brown water trout stream in Dickinson County, Michigan. The Reference site received 4.9–6.5 times less exposure to ground electric fields and from 300 to 334 times less exposure to magnetic flux from 1989 to 1993 when the antenna was operational at 76 Hz than did the Antenna site. The objective of the study was to determine if ELF electromagnetic fields had caused changes in structure and/or function of algal communities in the Ford River. Significant differences in chlorophyll a standing crop and daily accumulation rate (a surrogate for primary productivity), and organic matter standing crop and daily accumulation rate were observed between the Reference and Antenna site after the antenna became operational. These four related community function variables all increased at the Antenna site with largest and most consistent increases occurring for chlorophyll measures. Compared to pre-operational data, the increase in chlorophyll at the Antenna site also occurred during a period of low amperage testing in 1986–1988, and did not increase further when the antenna became fully operational in 1989, indicating a low threshold for response. There was no significant differences between the Antenna and Reference sites in community structure variables such as diversity, evenness and the relative abundance of dominant diatoms. Thus, 76 Hz ELF electromagnetic radiation apparently did not change the basic makeup of the diatom community but did increase accumulation rates and standing crops of chlorophyll a and organic matter.  相似文献   

4.
Electromagnetic fields have been demonstrated to elicit thermoregulatory responses, neuroen-docrine, neurochemical modulations, and behavioral reactions. These physiologic regulatory processes are exquisitely tuned, interrelated functions that constitute sensitive indicators of organismic responses to radiofrequency energy absorption (the radio frequency portion of the electromagnetic spectrum includes as one part microwaves). Assessment of the integration and correlation of these functions relative to the thermal inputs and homeokinetic reactions of the individual subjected to radiofrequency energy should permit differentiation between potential hazards that might compromise the individual's ability to maintain normal physiologic function and effects that are compensated by physiologic redundancy.  相似文献   

5.
Stem cells are one of the most important sources to develope a new strategy for repairing bone lesions through tissue engineering. Osteogenic differentiation of stem cells can be affected by various factors such as biological, chemical, physiological, and physical ones. The application of ELF-EMFs has been the subject of many research in bone tissue engineering and evidence suggests that this exogenous physical stimulus can promote osteogenic differentiation in several types of cells. The purpose of this paper is to review the current knowledge on the effects of EMFs on stem cells in bone tissue engineering studies. We recapitulated and analyzed 39 articles that were focused on the application of EMFs for bone tissue engineering purposes. We tabulated scattered information from these articles for easy use and tried to provide an overview of conducted research and identify the knowledge gaps in the field.  相似文献   

6.
Dividing human peripheral lymphocytes from 10 normal adults (5 males and 5 females) were exposed in vitro to low level 60-Hz electromagnetic fields for 69 hours. The current density of the electrical field was 30 microA/cm2, while the magnetic field was either 1 or 2 gauss. The cytological endpoints measured were mitotic rate and chromosome breakage. No statistically significant differences, indicative of a field effect, were observed between treated and control cells whether exposed to an electric field, a magnetic field, or to various combinations of the two.  相似文献   

7.
Idiopathic environmental intolerance attributed to electromagnetic fields (IEI‐EMF) is a controversial illness in which people report symptoms that they believe are triggered by exposure to EMF. Double‐blind experiments have found no association between the presence of EMF and self‐reported outcomes in people with IEI‐EMF. No systematic review has assessed whether EMF exposure triggers physiological or cognitive changes in this group. Using a systematic literature search, we identified 29 single or double‐blind experiments in which participants with IEI‐EMF were exposed to different EMF levels and in which objectively measured outcomes were assessed. Five studies identified significant effects of exposure such as reduced heart rate and blood pressure, altered pupillary light reflex, reduced visual attention and perception, improved spatial memory, movement away from an EMF source during sleep and altered EEG during sleep. In most cases, these were isolated results that other studies failed to replicate. For the sleep EEG findings, the results reflected similar changes in the IEI‐EMF participants and a non‐IEI‐EMF control group. At present, there is no reliable evidence to suggest that people with IEI‐EMF experience unusual physiological reactions as a result of exposure to EMF. This supports suggestions that EMF is not the main cause of their ill health. Bioelectromagnetics. Bioelectromagnetics 32:593–609, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

8.
Osteogenesis is a complex series of events involving the differentiation of mesenchymal stem cells to generate new bone. In this study, we examined the effect of pulsed electromagnetic fields (PEMFs) on cell proliferation, alkaline phosphatase (ALP) activity, mineralization of the extracellular matrix, and gene expression in bone marrow mesenchymal stem cells (BMMSCs) during osteogenic differentiation. Exposure of BMMSCs to PEMFs increased cell proliferation by 29.6% compared to untreated cells at day 1 of differentiation. Semi‐quantitative RT‐PCR indicated that PEMFs significantly altered temporal expression of osteogenesis‐related genes, including a 2.7‐fold increase in expression of the key osteogenesis regulatory gene cbfa1, compared to untreated controls. In addition, exposure to PEMFs significantly increased ALP expression during the early stages of osteogenesis and substantially enhanced mineralization near the midpoint of osteogenesis. These results suggest that PEMFs enhance early cell proliferation in BMMSC‐mediated osteogenesis, and accelerate the osteogenesis. Bioelectromagnetics 31:209–219, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

9.
Based on nonlinear phenomena of biophoton emission observed in the past, an interference model concerning with the mechanism of interaction between living organisms and electromagnetic fields was raised. Caused by biological nonlinearly polarizable double layer, destructive interference of incoming and reflected waves establishes in the outside. As a consequence, in the inside constructive interference takes place at the same time. The interference patterns may play an important role in biological self organization and in biological functions. We investigate the boundary conditions necessary for explaining these non-linear optical effects in terms of the phase conjugation. It turns out that there are solutions of the Maxwell equations which satisfy destructive interference of biophotons in agreement with the experimental results. Necessary provisions are nonlinearly polarizable optically active double layers of distances which are small compared to the wavelength of light. In addition, they have to be able to move into the nodal planes of the impinging waves within a small time interval compared to the coherence time. These conditions are likely fulfilled in the optically dense, but ordered and optically excited, highly polarizable living matter.  相似文献   

10.
Based on nonlinear phenomena of biophoton emission observed in the past, an interference model concerning with the mechanism of interaction between living organisms and electromagnetic fields was raised. Caused by biological nonlinearly polarizable double layer, destructive interference of incoming and reflected waves establishes in the outside. As a consequence, in the inside constructive interference takes place at the same time. The interference patterns may play an important role in biological self organization and in biological functions. We investigate the boundary conditions necessary for explaining these non-linear optical effects in terms of the phase conjugation. It turns out that there are solutions of the Maxwell equations which satisfy destructive interference of biophotons in agreement with the experimental results. Necessary provisions are nonlinearly polarizable optically active double layers of distances which are small compared to the wavelength of light. In addition, they have to be a  相似文献   

11.
Life on earth has evolved in a sea of natural electromagnetic (EM) fields. Over the past century, this natural environment has sharply changed with introduction of a vast and growing spectrum of man-made EM fields. From models based on equilibrium thermodynamics and thermal effects, these fields were initially considered too weak to interact with biomolecular systems, and thus incapable of influencing physiological functions. Laboratory studies have tested a spectrum of EM fields for bioeffects at cell and molecular levels, focusing on exposures at athermal levels. A clear emergent conclusion is that many observed interactions are not based on tissue heating. Modulation of cell surface chemical events by weak EM fields indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies, and neurotransmitters to their specific binding sites. Calcium ions play a key role in this amplification. These studies support new concepts of communication between cells across the barriers of cell membranes; and point with increasing certainty to an essential physical organization in living matter, at a far finer level than the structural and functional image defined in the chemistry of molecules. New collaborations between physical and biological scientists define common goals, seeking solutions to the physical nature of matter through a strong focus on biological matter. The evidence indicates mediation by highly nonlinear, nonequilibrium processes at critical steps in signal coupling across cell membranes. There is increasing evidence that these events relate to quantum states and resonant responses in biomolecular systems, and not to equilibrium thermodynamics associated with thermal energy exchanges and tissue heating.  相似文献   

12.
ATP production in mitochondria depends on the nuclear spin and magnetic moment of Mg2+ ion in creatine kinase and ATPase. Consequently, the enzymatic synthesis of ATP is an ion-radical process and depends on the external magnetic field and microwave fields that control the spin states of ion-radical pairs and influence the ATP synthesis. The chemical mechanism of ATP synthesis and the origin of biological effects of electromagnetic (microwave) fields are discussed.  相似文献   

13.
Osteoarthritis (OA) is the most frequent joint disease, characterized by degradation of extracellular matrix and alterations in chondrocyte metabolism. Some authors reported that electromagnetic fields (EMFs) can positively interfere with patients affected by OA, even though the nature of the interaction is still debated. Human primary osteoarthritic chondrocytes isolated from the femoral heads of OA-patients undergoing to total hip replacement, were cultured in vitro and exposed 30?min/day for two weeks to extremely-low-frequency electromagnetic field (ELF) with fixed frequency (100?Hz) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF) with variable frequencies, intensities and waveforms. Sham-exposed (S.E.) cells served as control group. Cell viability was measured at days 2, 7 and 14. After two weeks, cell lysates were processed using a proteomic approach. Chondrocyte exposed to ELF and TAMMEF system demonstrated different viability compared to untreated chondrocytes (S.E.). Proteome analysis of 2D-Electrophoresis and protein identification by mass spectrometry showed different expression of proteins derived from nucleus, cytoplasm and organelles. Function analysis of the identified proteins showed changes in related-proteins metabolism (glyceraldeyde-3-phosphate-dehydrogenase), stress response (Mn-superoxide-dismutase, heat-shock proteins), cytoskeletal regulation (actin), proteinase inhibition (cystatin-B) and inflammation regulatory functions (S100-A10, S100-A11) among the experimental groups (ELF, TAMMEF and S.E.). In conclusion, EMFs do not cause damage to chondrocytes, besides stimulate safely OA-chondrocytes and are responsible of different protein expression among the three groups. Furthermore, protein analysis of OA-chondrocytes treated with ELF and the new TAMMEF systems could be useful to clarify the pathogenetic mechanisms of OA by identifying biomarkers of the disease.  相似文献   

14.
The appearance of endogenous electromagnetic fields in biological systems is a widely debated issue in modern science. The electrophysiological fields have very tiny intensities and it can be inferred that they are rapidly decreasing with the distance from the generating structure, vanishing at very short distances. This makes very hard their detection using standard experimental methods. However, the existence of fast-moving charged particles in the macromolecules inside both intracellular and extracellular fluids may envisage the generation of localized electric currents as well as the presence of closed loops, which implies the existence of magnetic fields. Moreover, the whole set of oscillatory frequencies of various substances, enzymes, cell membranes, nucleic acids, bioelectrical phenomena generated by the electrical rhythm of coherent groups of cells, cell-to-cell communication among population of host bacteria, forms the increasingly complex hierarchies of electromagnetic signals of different frequencies which cover the living being and represent a fundamental information network controlling the cell metabolism. From this approach emerges the concept of electromagnetic homeostasis: that is, the capability of the human body to maintain the balance of highly complex electromagnetic interactions within, in spite of the external electromagnetic noisy environment. This concept may have an important impact on the actual definitions of heal and disease.  相似文献   

15.
Effects of extremely low frequency (ELF) electromagnetic fields (EMFs) on activation of angiogenesis were analysed using cultured umbilical human vein endothelial cells (HUVECs). The cultures were exposed to a sinusoidal EMF to intensity of 1 mT, 50 Hz for up to 12 h. EMFs increased the degree of endothelial cell proliferation and tubule formation, coupled by an acceleration in the process of wound healing. Since this process is physiologically accompanied by a large modification in the structural organization of actin and focal adhesions, we analyzed the rearrangement of some cytoskeleton elements demonstrating a major reorganization of the fibres and of the focal adhesion complexes after EMF exposure. Finally, Western blot analysis revealed a significant increase in phosphorylation as well as the overall expression of VEGF receptor 2 (KDR/Flk-1) suggesting that EMFs may modulate in vitro some endothelial functions correlated to angiogenesis through signal transduction pathways dependent on VEGF.  相似文献   

16.
The effects of electromagnetic fields (EMFs) in physiotherapy have been discussed mainly with regard to the patient's safety, while the operator's safety is neglected. This paper presents the medical assessment and specific tendencies in the health status of personnel in physical therapy wards – where the EMFs are everyday background factor. This paper summarizes the somatic part of results from the study among physiotherapy personnel from facilities with different equipment and work load by using survey card designed by us for health status screening in somatic and neurobehavioral aspects. The main specific somatic findings and complaints in investigated group include parodontosis – 42%; cardiovascular disorders – 41.6%; allergic conditions with skin or systemic manifestation – 40.8%; photosensibilization – 34.1%; skin diseases – 31.5%; musculoskeletal disorders – 30.0% and neoplasm disorders – 7.5%. Keeping in mind that better part of the personnel in the physical therapy units is female, a special attention was paid to the pathology of the reproductive system; menstrual disturbances are observed in 20.0%. These findings are collected in complex for the first time in physiotherapy personnel, and when data were available from other professional groups, we found a good correlation.  相似文献   

17.
An experimental study was carried out in rats with the purpose of demonstrating the capacity of pulsed electromagnetic fields (PEMFs) to stimulate regeneration of the peripheral nervous system (PNS). Wistar and Brown Norway (BN) rats were used. Direct sciatic nerve anastomoses were performed after section or allograft interposition. Treatment groups then received 4 weeks of PEMFs. Control groups received no stimulation. The evaluation of the results was carried out by quantitative morphometric analysis, demonstrating a statistically significant increase in regeneration indices (P < 0.05) in the stimulated groups (9000 +/- 5000 and 4000 +/- 6000) compared to the non-stimulated groups (2000 +/- 4000 and 700 +/- 200). An increase of NAD specific isocitrate dehydrogenase (IDH) activity was found along with an increase in the activity of acetyl cholinesterase at the motor plate. The present study might lead to the search for new alternatives in the stimulation of axonal regenerative processes in the PNS and other possible clinical applications.  相似文献   

18.
Although various treatments have been presented for phantom pain, there is little proof supporting the benefits of pharmacological treatments, surgery or interventional techniques, electroconvulsive therapy, electrical nerve stimulation, far infrared ray therapy, psychological therapies, etc. Here, we report the preliminary results for phantom pain reduction by low-frequency and intensity electromagnetic fields under clinical circumstances. Our method is called as Electromagnetic-Own-Signal-Treatment (EMOST). Fifteen people with phantom limb pain participated. The patients were treated using a pre-programmed, six sessions. Pain intensity was quantified upon admission using a 0–10 verbal numerical rating scale. Most of the patients (n = 10) reported a marked reduction in the intensity of phantom limb pain. Several patients also reported about improvement in their sleep and mood quality, or a reduction in the frequency of phantom pain after the treatments. No improvements in the reduction of phantom limb pain or sleep and mood improvement were reported in the control group (n = 5). Our nonlinear electromagnetic EMOST method may be a possible therapeutic application in the reduction of phantom limb pain. Here, we also suggest that some of the possible effects of the EMOST may be achieved via the redox balance of the body and redox-related neural plasticity.  相似文献   

19.
Idiopathic Environmental Intolerance attributed to electromagnetic fields (IEI‐EMF; formerly ‘electromagetic hypersensitivity’) is a medically unexplained illness in which subjective symptoms are reported following exposure to electrical devices. In an earlier systematic review, we reported data from 31 blind provocation studies which had exposed IEI‐EMF volunteers to active or sham electromagnetic fields and assessed whether volunteers could detect these fields or whether they reported worse symptoms when exposed to them. In this article, we report an update to that review. An extensive literature search identified 15 new experiments. Including studies reported in our earlier review, 46 blind or double‐blind provocation studies in all, involving 1175 IEI‐EMF volunteers, have tested whether exposure to electromagnetic fields is responsible for triggering symptoms in IEI‐EMF. No robust evidence could be found to support this theory. However, the studies included in the review did support the role of the nocebo effect in triggering acute symptoms in IEI‐EMF sufferers. Despite the conviction of IEI‐EMF sufferers that their symptoms are triggered by exposure to electromagnetic fields, repeated experiments have been unable to replicate this phenomenon under controlled conditions. A narrow focus by clinicians or policy makers on bioelectromagnetic mechanisms is therefore, unlikely to help IEI‐EMF patients in the long‐term. Bioelectromagnetics 31:1–11, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

20.
The purpose of our study is to assist in understanding the effects of wireless electromagnetic waves on carbonic anhydrase (CA) and acetylcholinesterase (AChE) enzymes activities in the different tissues of the rats. For this purpose, two different groups each of which contains eight rats (n = 8) were formed as being control group and wireless electromagnetic wave‐administered group. The rats were necropsied after 60 min from the injection of chemicals into the rats intraperitoneally. The different tissues of the rats were extracted. CA and AChE enzymes activities were measured for each tissue. All the experimental results were provided in mean ± S.D. Statistical significance was identified to be P < 0.05. It was observed that there were significant changes of enzyme activities in wireless‐administered group in salivary gland, stomach, colon, liver, and striated muscle tissues.  相似文献   

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