Abstract:
:We have shown that 50 Hz sinusoidal magnetic fields within the 5-10 microTesla (microT) rms range cause an intensity-dependent reduction in nerve growth factor (NGF) stimulation of neurite outgrowth (NO) in PC-12 cells. Here we report on the frequency dependence of this response over the 15-70 Hz range at 5 Hz intervals. Primed PC-12 cells were plated in collagen-coated, 60 mm plastic petri dishes with or without 5 ng/ml NGF and were exposed to sinusoidal magnetic fields for 22 h in a CO2 incubator at 37 degrees C. One 1,000-turn coil, 20 cm in diameter, generated vertically oriented magnetic fields. The dishes were stacked on the center axis of the coil to provide a range of intensities between 3.5 and 9.0 microT rms. The flux density of the ambient DC magnetic field was 37 microT vertical and 19 microT horizontal. The assay consisted of counting over 100 cells in the central portion (radius < or = 0.3 cm) of each dish and scoring cells positive for NO. Sham exposure of cells treated identically with NGF demonstrated no difference in the percentage of cells with NO between exposed and magnetically shielded locations within the incubator. Analysis of variance demonstrated flux density-dependent reductions in NGF-stimulated NO over the 35-70 Hz frequency range, whereas frequencies between 15 Hz and 30 Hz produced no obvious reduction. The results also demonstrated a relative maximal sensitivity of cells at 40 Hz with a possible additional sensitivity region at or above 70 Hz. These findings suggest a biological influence of perpendicular AC/DC magnetic fields different from those identified by the ion parametric resonance model, which uses strictly parallel AC/DC fields.
journal_name
Bioelectromagneticsjournal_title
Bioelectromagneticsauthors
Blackman CF,Benane SG,House DEdoi
10.1002/bem.2250160607subject
Has Abstractpub_date
1995-01-01 00:00:00pages
387-95issue
6eissn
0197-8462issn
1521-186Xjournal_volume
16pub_type
杂志文章abstract::Experiments were conducted to see whether the cellular response to electromagnetic (EM) fields occurs through a detection process involving temporal sensing. L929 cells were exposed to 60 Hz magnetic fields and the enhancement of ornithine decarboxylase (ODC) activity was measured to determine cellular response to the...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/(sici)1521-186x(1997)18:5<388::aid-bem6>3.
更新日期:1997-01-01 00:00:00
abstract::Effects of magnetic fields (MFs) on the activities of antioxidant enzymes of suspension-cultured tobacco cells were investigated. Compared with the control cells, exposure of the cells to static MF with the magnitudes of 10 and 30 mT for 5 days, 5 h each day, increased the activity of superoxide dismutase (SOD). In co...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20262
更新日期:2007-01-01 00:00:00
abstract::In an hypothesis-generating case-control study of amyotrophic lateral sclerosis, lifetime occupational histories were obtained. The patients (n = 28) were clinic based. The occupational exposure of interest in this report is electromagnetic fields (EMFs). This is the first and so far the only exposure analyzed in this...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/(sici)1521-186x(1997)18:1<28::aid-bem6>3.0
更新日期:1997-01-01 00:00:00
abstract::We conducted a pilot study to assess magnetic field levels in electric compared to gasoline-powered vehicles, and established a methodology that would provide valid data for further assessments. The sample consisted of 14 vehicles, all manufactured between January 2000 and April 2009; 6 were gasoline-powered vehicles ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.21730
更新日期:2013-02-01 00:00:00
abstract::To investigate the ability of prokaryotic microorganisms to activate strategies in adapting themselves to the environmental stress induced by exposure to extremely low frequency electromagnetic fields (ELF-EMF), cultures of Escherichia coli ATCC 700926 exposed at 50 Hz EMF (0.1, 0.5, 1.0 mT), and the respective sham-e...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20391
更新日期:2008-05-01 00:00:00
abstract::The objective of this study was to investigate if persons with implantable medical devices are intrinsically protected by the current electromagnetic safety guidelines. For inter-laboratory comparisons, the U.S. Food and Drug Administration has defined a generic implant as consisting of an insulated wire with noninsul...
journal_title:Bioelectromagnetics
pub_type: 临床试验,杂志文章
doi:10.1002/bem.21695
更新日期:2012-07-01 00:00:00
abstract::The temperature distribution inside a lossy sphere resulting from the absorption of microwave energy was approximated by successive numerical iterations. of the thermal energy equation. Heat transfer within the sphere by conduction was considered. In the model energy was not dissipated by convection but was contained ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250010309
更新日期:1980-01-01 00:00:00
abstract::There are large disparities between basic restrictions for exposure to extremely low-frequency (0-3 kHz) Electric and Magnetic Fields set by two major international bodies. Both bodies agree that these basic restrictions should prevent neuro-stimulatory effects: the retinal phosphene at frequencies up to a few hundred...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20412
更新日期:2008-09-01 00:00:00
abstract::Fertile eggs of the Coturnix quail were exposed twice a day for 30 min to 2.45-GHz continuous wave radiation at power densities of 25 or 50 mW cm-2 throughout the 17-day incubation period. Other eggs were exposed to 20 degrees C or 24 degrees C temperatures twice daily. Repeated exposures to 20 degrees C, 24 degrees C...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250060307
更新日期:1985-01-01 00:00:00
abstract::Possible effects of 1439 MHz electromagnetic near field (EMF) exposure on the blood-brain barrier (BBB) were investigated using immature (4 weeks old) and young (10 weeks old) rats, equivalent in age to the time when the BBB development is completed and the young adult, respectively. Alteration of BBB related genes, s...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20138
更新日期:2005-10-01 00:00:00
abstract::Through the use of the non-invasive vibrating probe technique for detecting extracellular ionic currents developed in 1974 [Jaffe and Nuccitelli: J Cell Biol 63:614-628, 1974], embryonic currents have been detected in a wide range of animal systems (recently reviewed in [Nuccitelli, Noninvasive Techniques in Cell Biol...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,评审
doi:10.1002/bem.2250130714
更新日期:1992-01-01 00:00:00
abstract::We summarize the results of several of our recent studies on the dielectric properties of protein solutions, tissues, and nonionic microemulsions at microwave frequencies extending to 18 GHz. The data in all cases are analyzed using the Maxwell mixture theory to determine the dielectric properties of the suspending wa...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250030108
更新日期:1982-01-01 00:00:00
abstract::The clinical and preclinical use of high-field intensity (HF, 3 T and above) magnetic resonance imaging (MRI) scanners have significantly increased in the past few years. However, potential health risks are implied in the MRI and especially HF MRI environment due to high-static magnetic fields, fast gradient magnetic ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20664
更新日期:2011-10-01 00:00:00
abstract::Occupational exposure to the high static magnetic fields (SMFs) during magnetic resonance imaging (MRI) examinations raises concerns of adverse health effects. In this study, personal exposure monitoring of the magnetic fields during routine examinations in two 3 T MRI systems was carried out. A three-axis Hall magnet...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,多中心研究
doi:10.1002/bem.21817
更新日期:2014-01-01 00:00:00
abstract::The widespread use of mobile phones and Wi-Fi-based communication devices makes exposure to radiofrequency electromagnetic fields (RF-EMF) unavoidable. Previous experiments have revealed the tumor-promoting effects of non-ionizing RF-EMF in adult carcinogen-treated mice in utero. To extend these investigations, we tes...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.22301
更新日期:2020-12-01 00:00:00
abstract::Magnetotactic bacteria produce nanometer-size intracellular magnetic crystals. The superior crystalline and magnetic properties of magnetosomes have been attracting much interest in medical applications. To investigate effects of intense static magnetic field on magnetosome formation in Magnetospirillum magneticum AMB...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20469
更新日期:2009-05-01 00:00:00
abstract::Magnetite, the only known biogenic material with ferromagnetic properties, has been identified as a biochemical precipitate in three of the five kingdoms of living organisms, with a fossil record that now extends back nearly 2 billion years. In the magnetotactic bacteria, protoctists, and fish, single-domain crystals ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,评审
doi:10.1002/bem.2250100304
更新日期:1989-01-01 00:00:00
abstract::Low-energy pulsed electromagnetic field (PEMF) therapy has been suggested as a promising therapy to increase microcirculation, which is of great concern in patients with fibromyalgia. This study evaluated the effectiveness of PEMF therapy on the treatment of fibromyalgia. A group of 108 women with fibromyalgia were al...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,随机对照试验
doi:10.1002/bem.22127
更新日期:2018-07-01 00:00:00
abstract::B lymphocytes collected from normal ICR Swiss mouse spleens were exposed in vitro in a Crawford cell to 147-MHz radiofrequency (RF) radiation, amplitude modulated by a 9-, 16-, or 60-Hz sine wave. The power densities ranged between 0.11 and 48 mW/cm2. The irradiated samples and the controls were maintained at 37 degre...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250040206
更新日期:1983-01-01 00:00:00
abstract::The use of wireless digital communication devices like GSM, WCDMA, HSPA, DECT, and WiFi changes the exposure of electromagnetic waves toward the user. Concentrating on the power variations on a slow and fast time scale, these new systems are discussed. Experimental results for both uplink and downlink are included for...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20569
更新日期:2010-05-01 00:00:00
abstract::Rats were tested for neurobehavioral alterations immediately after exposure to 2.45-GHz (CW) microwave radiation at 10 mW/cm2 for 7 h. Behavioral tests used were locomotor activity, startle to an acoustic stimulus and acquisition and retention of a shock-motivated passive avoidance task. Both horizontal and vertical c...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250090307
更新日期:1988-01-01 00:00:00
abstract::Little is known about the influence of magnetic fields on growth of primitive eukaryotes such as the ciliate Paramecium. The latter are known to exhibit interesting characteristics such as electrotaxis, gravitaxis, and membrane excitability not commonly encountered in higher organisms. This preliminary study reports t...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20172
更新日期:2006-01-01 00:00:00
abstract::In May 2011, the International Agency on Cancer in Research (IARC) issued an official statement concluding that cell phone usage was "possibly carcinogenic to humans." There have been considerable doubts that non-experts and experts alike fully understood what IARC's categorization actually meant, as "possibly carcino...
journal_title:Bioelectromagnetics
pub_type: 信件
doi:10.1002/bem.21851
更新日期:2014-07-01 00:00:00
abstract::C57/B1 mice were exposed during pregnancy (gestation days 0-19) to a 20 kHz magnetic field (MF). The asymmetric sawtooth-waveform magnetic field in the exposed racks had a flux density of 15 microT (peak to peak). After 19 days, the exposure was terminated, and the mice were housed individually under normal laboratory...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250160409
更新日期:1995-01-01 00:00:00
abstract::The objective was to study the risk of cytogenetic damage among high voltage laboratory workers exposed to electromagnetic fields and mineral oil. This is a cross sectional study of 24 exposed and 24 matched controls in a Norwegian transformer factory. The exposure group included employees in the high voltage laborato...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.33
更新日期:2001-04-01 00:00:00
abstract::The US National Electrical Code's (NEC) requirement to ground a home's electrical service to the residential water line results in a voltage between the water line and earth, V W-E. The voltage may result from ground return current that flows into the earth via the water line or from inductive effects from other sourc...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20033
更新日期:2004-10-01 00:00:00
abstract::In this acceptance address for the Bioelectromagnetics Society's 2001 d'Arsonval Award, Dr. Tenforde reviews the highlights of the nonionizing field aspects of his research and scientific service career. These are focused in four areas: (a). development and application of microelectrophoretic methods to probe the surf...
journal_title:Bioelectromagnetics
pub_type: 传,历史文章
doi:10.1002/bem.10090
更新日期:2003-01-01 00:00:00
abstract::Our previous studies showed that extremely low frequency magnetic fields (ELF-MFs) inhibited tumor growth and change proportion of splenic regulatory T cells (Treg cells). Here, we focus on the effect of ELF-MFs on lung metastatic melanoma mouse model and the regulatory mechanism of ELF-MFs on the differentiation of T...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.21954
更新日期:2016-02-01 00:00:00
abstract::This paper presents a theoretical analysis of electromagnetic environments in power substations in service. A new analytical method is developed and applied to magnetic field calculations in 187-kV and 66-kV substations. Experimental results verify that the method offers a good prediction of the magnetic field profile...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250100106
更新日期:1989-01-01 00:00:00
abstract::Irreversible changes in the heat capacity of human erythrocyte ghost suspensions due to the effect of 330-MHz radiofrequency radiation (at a specific absorption rate of approximately 9 mW/g) were detected by the method of scanning differential microcalorimetry. Using the data obtained from the analysis of infrared spe...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250050406
更新日期:1984-01-01 00:00:00