Abstract:
:The dielectric behavior of the aqueous solutions of three widely differing macromolecules has been investigated: myoglobin, polyvinylpyrrolidone (PVP), and human serum low-density lipoprotein (LDL). It was not possible to interpret unambiguously the dielectric properties of the PVP solution in terms of water structure. The best interpretation of the dielectric data on the myoglobin and LDL solutions was that, in both cases, the macromolecule attracts a layer of water of hydration one or two water molecules in width. For LDL, this corresponds to a hydration factor of only 0.05 g/g, whereas for myoglobin the figure is nearer 0.6 g/g. With myoglobin, part of the water of hydration exhibits its dispersion at frequencies of a few GHz, and the rest disperses at lower frequencies, perhaps as low as 10-12 MHz. The approximate constancy of the width of the hydration shell for two molecules as dissimilar in size as LDL and myoglobin confirms that the proportion of water existing as water of hydration in a biological solution depends critically on the size of the macromolecules as well as on their concentration.
journal_name
Bioelectromagneticsjournal_title
Bioelectromagneticsauthors
Grant EH,McClean VE,Nightingale NR,Sheppard RJ,Chapman MJdoi
10.1002/bem.2250070206subject
Has Abstractpub_date
1986-01-01 00:00:00pages
151-62issue
2eissn
0197-8462issn
1521-186Xjournal_volume
7pub_type
杂志文章abstract::Chemical and bacterial synthesis of a thermochemiluminescent polymer known as diazoluminomelanin (DALM) has been previously reported. This paper focuses on the intracellular synthesis of aminomelanin (AM) in mammalian cell lines and subsequent DALM synthesis from this core molecule. B16 melanoma cells, HL-60 myeloid l...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250150406
更新日期:1994-01-01 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::We study the effect of microwaves at 2,450 MHz on protein unfolding using surface plasmon resonance sensing. Our experimental method makes use of the fact that unfolding proteins tend to bind to chaperones on their unfolding pathway and this attachment is readily monitored by surface plasmon resonance. We use the prot...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20382
更新日期:2008-05-01 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::This study examined whether 60 Hz magnetic field (MF) exposure alters intracellular calcium levels ([Ca(2+)](i)) in isolated bovine adrenal chromaffin cells, a classic model of neural responses. [Ca(2+)](i) was monitored by fluorescence video imaging of cells loaded with the calcium indicator fluo-4 during exposures t...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.10045
更新日期:2002-12-01 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::There is growing public concern that radio frequency electromagnetic fields may have adverse biological effects. In the present study eight healthy male students were tested to see whether or not radio frequency electromagnetic fields as used in modern digital wireless telecommunication (GSM standard) have noticeable ...
journal_title:Bioelectromagnetics
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/bem.51
更新日期:2001-05-01 00:00:00
abstract::The level of exposure of laboratory animals to 60-Hz electric fields is commonly specified in terms of the unperturbed field strength present before the introduction of experimental subjects and their cages. In the research reported in this paper, rats were housed in two parallel rows in 12.4 cm x 25.1 cm x 10.2 cm hi...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250020105
更新日期:1981-01-01 00:00:00
abstract::Ozone can be produced by corona discharge either in dry air or when one electrode is submerged in water. Since ozone is toxic, we examined whether ozone production by corona near laboratory animals could reach levels of concern. Male rats were exposed to a corona discharge and the concentration of ozone produced was m...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.10161
更新日期:2004-02-01 00:00:00
abstract::Different species of ciliates (Paramecium biaurelia, Loxodes striatus, Tetrahymena thermophila) have been taken as model systems to study the effects of extremely low-frequency electromagnetic fields (50 Hz, 0.5-2.0 mT) on the cellular level. A dose-dependent increase in the mean swimming velocity and a decrease in th...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/(sici)1521-186x(1997)18:7<491::aid-bem4>3.
更新日期:1997-01-01 00:00:00
abstract::Drosophila larvae reared inside a micro-metal box with an internal field strength 0.004 microT, were treated with a magnetic field of 50 Hz, 8 microT. for 20 min. Control experienced 0.004 microT. Cellular transcript levels were assessed using slot blots and quantified using a Phosphorimager. Blots were hybridised usi...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:
更新日期:1999-01-01 00:00:00
abstract::Exposures to radiofrequency (RF) energy above 6 GHz are characterized by shallow energy penetration, typically limited to the skin, but the subsequent increase in skin temperature is largely determined by heat transport in subcutaneous layers. A detailed analysis of the energy reflection, absorption, and power density...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,评审
doi:10.1002/bem.22110
更新日期:2018-04-01 00:00:00
abstract::The potential use of multiple-frequency-band radiometry as a means of noninvasive sensing of one-dimensional temperature profiles is presented in this communication. The radiative energy transfer equation is solved numerically. Ideal-condition thermal noise spectra and distributions of received energy, associated with...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250060406
更新日期:1985-01-01 00:00:00
abstract::The impedance spectroscopy technique (IST) was used for studying the effect of a 0.5 T magnetic field on the electrical properties of whole human blood. A Solartron SI 1260 spectrometer was used to measure the impedance spectra of magnetic field exposed blood samples compared to non-exposed samples. An equivalent elec...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20132
更新日期:2005-10-01 00:00:00
abstract::The influence of tissue compression and external thermal modulation on passive detection of breast tumors using medical microwave radiometry was investigated using multi-physics numerical modeling. A three-dimensional numerical model of the pendant breast with 10 and 6 mm diameter tumors at varying depths (15 mm, 30 m...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.22184
更新日期:2019-05-01 00:00:00
abstract::Several effects of power-frequency (50/60 Hz) magnetic fields (PF-MF) of weak intensity have been hypothesized in animals and humans. No valid mechanism, however, has been proposed for an interaction between PF-MF and biological tissues and living beings at intensities relevant to animal and human exposure. Here we pr...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20568
更新日期:2010-07-01 00:00:00
abstract::The effects of exposure to clinical magnetic resonance imaging (MRI) on analgesia induced by the mu opiate agonist, fentanyl, was examined in mice. During the dark period, adult male mice were exposed for 23.2 min to the time-varying (0.6 T/sec) magnetic field (TVMF) component of the MRI procedure. Following this expo...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250090208
更新日期:1988-01-01 00:00:00
abstract::A retrospective study on reproductive hazards was performed among 542 employees at Swedish power plants. Questionnaires were answered by 89% of the employees. Data on pregnancies were checked by studying hospital case records. There was a statistically significant, decreased frequency of "normal" pregnancy outcome, al...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250040109
更新日期:1983-01-01 00:00:00
abstract::A novel exposure system for double-blind human electromagnetic provocation studies has been developed that satisfies the precision, control of fields and potential artifacts, and provides the flexibility to investigate the response of hypotheses-driven electromagnetic field exposure schemes on brain function, ranging ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.21710
更新日期:2012-09-01 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::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::In a previous investigation we reported that exposure to a moderate (300 mT) static magnetic field (SMF) causes transient DNA damage and promotes mitochondrial biogenesis in human umbilical vein endothelial cells (HUVECs). To better understand the response of HUVECs to the 300 mT SMF, a high-quality subtracted cDNA li...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20686
更新日期:2012-01-01 00:00:00
abstract::This paper investigates the effect of relevant physical parameters on transient temperature elevation induced in human tissues by electromagnetic waves in the terahertz (THz) band. The problem is defined by assuming a plane wave, which, during a limited time interval, normally impinges on the surface of a 3-layer mode...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.21842
更新日期:2014-07-01 00:00:00
abstract::We have studied the effect of extremely low frequency electromagnetic fields (ELF-EMF) in the presence of a second stressor (mild heat shock) on the expression of a lacZ reporter gene under the control of hsp16 or hsp70 promoters in two transgenic strains of C. elegans. The expression of the reporter gene was studied ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/(sici)1521-186x(200002)21:2<100::aid-bem4>
更新日期:2000-02-01 00:00:00
abstract::Vertigo-like sensations or apparent perception of movement are reported by some subjects and operators in and around high field whole body magnetic resonance body scanners. Induced currents (which modulate the firing rate of the vestibular hair cell), magneto-hydrodynamics (MDH), and tissue magnetic susceptibility dif...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20316
更新日期:2007-07-01 00:00:00
abstract::Stress proteins are important in protection during cardiac ischemia/reperfusion (cessation and return of blood flow) and are reportedly induced by electromagnetic (EM) fields. This suggests a possible ischemia protection role for EM exposures. To test this, chick embryos (96 h) were exposed to 60 Hz magnetic fields pr...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/(sici)1521-186x(1998)19:8<498::aid-bem8>3.
更新日期:1998-01-01 00:00:00
abstract::Research conducted over the past 5 years has addressed the hypothesis that the reported association between residential magnetic fields and childhood leukemia may be explained by exposure to contact current. The use of multi-grounded neutrals in electrical distribution and residential electrical wiring systems in the ...
journal_title:Bioelectromagnetics
pub_type: 杂志文章,评审
doi:10.1002/bem.20126
更新日期:2005-01-01 00:00:00
abstract::In the clinic, although several pharmacological agents or surgical procedures are used to treat diabetes and diabetes-induced neuropathic pain, their success has been limited. Therefore, development of different alternatives in treatments is very important. The purpose of this study was to determine the efficacy of pu...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20524
更新日期:2010-01-01 00:00:00
abstract::To assess the effect of a magnetic treatment on pain perception, we compared the sensory threshold in 18 healthy volunteers. We determined the threshold by noninvasive electrical stimulation of the tooth pulp and skin before and after exposure to an altered magnetic field of low intensity and to a sham treatment. Five...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.2250160505
更新日期:1995-01-01 00:00:00
abstract::This paper computationally verifies the effect of anesthesia on temperature variations in the rabbit eye due to microwave energy. The main reason for this investigation is that our previous paper suggested a reduction in blood flow due to the administration of anesthesia, resulting in an overestimated temperature incr...
journal_title:Bioelectromagnetics
pub_type: 杂志文章
doi:10.1002/bem.20251
更新日期:2006-12-01 00:00:00