OBJECTIVE: To improve the electromagnetic compatibility (EMC) quality of medical devices, improve the efficiency of EMC testing, and promote the speed of market approval. METHODS: The unqualified cases of EMC test items of medical devices in recent years were statistically analyzed, and the reasons of low EMC quality of medical devices were analyzed from the perspective of test. RESULTS: Based on the analysis of the reasons, the suggestions were given from the perspectives of medical device manufacturers and testing organizations. CONCLUSIONS In order to ensure the quality of EMC of medical devices, medical device manufacturers, regulatory authorities and inspection and testing institutions should strengthen the monitoring and evaluation of medical device electromagnetic compatibility, to ensure the safety of products work together to promote the development of the medical device industry healthily and orderly.
Electromagnetic Phenomena ; Industry ; Electromagnetic Fields

OBJECTIVETo predict the impact of MF radiation on human health.

METHODSThe vertical distribution of field intensity was estimated by analogism on the basis of measured values from simulation measurement.

RESULTSA kind of analogism on the basis of geometric proportion decay pattern is put forward in the essay. It showed that with increasing of height the field intensity increased according to geometric proportion law.

CONCLUSIONThis geometric proportion prediction model can be used to estimate the impact of MF radiation on inhabited environment, and can act as a reference pattern in predicting the environmental impact level of MF radiation.

Electromagnetic Phenomena ; Environment ; Models, Biological ; Radiation

Pulsed electric fields can induce various kinds of biological effects that are essentially different from the normal electric fields, especially the interactions of Nanosecond Pulsed electric field (nsPEF) with cells. The biological effects of different pulsed electric fields on cell membranes, cytoplasmic matrixes, cell growth are introduced in this paper. Based on these effects, some applications of pulsed electric fields in cancer therapy, gene therapy, and delivery of drugs are reviewed in details.
Cell Membrane ; metabolism ; radiation effects ; Cell Physiological Phenomena ; Electromagnetic Fields ; Electrophysiology ; Electroporation ; Genetic Therapy ; methods ; Neoplasms ; therapy

Cell Physiological Phenomena ; Electromagnetic Fields

The effects of the pulsed electromagnetic fields (PEMFs) of different intensity on bone mineral density (BMD) and biomechanical properties of rabbits' femur had been studied. Twenty-seven female white big ear rabbits were randomly divided into three groups. The magnetic groups were fed in 15 Hz PEMFs, which pulse duration was set to be 5 ms (6 h x d(-1)), the magnetic intensity was 10 x 10(-4) T and the other was 20 x 10(-4) T. Control group were just fed in coils, and the instrument of PEMFs was powered off. After six weeks, by examine BMD and biomechanical properties of the rabbits' femur, the effects of these PEMFs were studied. Compared with control group, the values of BMD, maximum load and structural rigidity of magnetic group were significantly increased (P < 0.05). In addition, there was significant increase in values of BMD and structural rigidity in group 10 x 10(-4) T in comparison with group 20 x 10(-4) T (P < 0.05). PEMFs is effective in improving BMD and biomechanical properties. The experiment indicated that there was evident "window-effect" during the treatment by PEMFs. It is favorable to the treatment and prevention of osteoporosis.
Animals ; Biomechanical Phenomena ; Bone Density ; physiology ; radiation effects ; Dose-Response Relationship, Radiation ; Electromagnetic Fields ; Female ; Femur ; metabolism ; physiology ; Osteoporosis ; prevention & control ; Rabbits ; Random Allocation

With the enforcement of YY 0505-2012, the testing items and evaluation points of radio frequency ablation catheter in electromagnetic compatibility field should be studied and discussed. Based on the requirements of relevant standards, this paper discusses on the testing items that should be applied and the evaluation points that should be focused on by analyzing the intended use and the structure of radio frequency ablation catheter, when it intends to apply registration individually with the basic knowledge of electromagnetic compatibility field.
Catheter Ablation ; instrumentation ; Electromagnetic Fields ; Electromagnetic Phenomena ; Evaluation Studies as Topic

This paper introduces ISO 14708-3:2017, the new edition of the international standard for implantable neurostimulator, and emphasizes the new requirements in the clause of protection from RF electromagnetic interference. To meet this new requirements, this paper presents a design of torso simulator for the testing of implantable neurostimulator. The design includes volume conductor, electrodes and grids, which can simulate the actual operating environment of implantable neurostimulator in RF electromagnetic interference testing. The torso simulator is verified by performance in the last part of the paper.
Electromagnetic Fields ; Electromagnetic Phenomena ; Implantable Neurostimulators ; standards ; Torso

This paper realized an electromagnetic tracking system based on electrically-controlled rotating magnetic field. A tracking system using the digital signal processor (DSP) as the control processing device was developed, including a controllable constant current source module, a magnetic field source module, a three-axis magnetic sensor and ADC interface circuit. The experimental results verified that each time the system could be stable positioning, average error of position was 0.282 cm, the average error of orientation was 0.696o, the positioning time was 1.572 s. Through calibration and further improvement of the hardware circuit, the performance of the system is expected to further improve.
Calibration ; Electromagnetic Phenomena ; Equipment Design ; Magnetic Fields

In the light of optical theory, we advanc an ultra-wideband impulse radiating antenna (IRA) which is composed of an ellipsoidal reflector and a cone radiator. The high-intensity ultra-short electric pulses radiated by IRA can be transferred into the deep target in tissue non-invasively and be focused effectively. With the focused picosecond electric pulses, the organelles (mitochondria) transmembrane potential shall change to collapse under which the tumor cells will be targetly induced to apoptosis, so the method of non-invasive treatment of tumors would be achieved. Based on the time-domain electromagnetic field theory, the propagation characteristics of picosecond electric pulses were analyzed with and without the context of biological tissue, respectively. The results show that the impulse characteristics of input pulse were maintained and the picosecond electric pulses can keep high resolution in target areas. Meanwhile, because of the dispersive nature of medium, the pulse amplitude of the pulses will attenuate and the pulse width will be broadened.
Apoptosis ; radiation effects ; Electric Stimulation Therapy ; methods ; Electrodes ; Electromagnetic Phenomena ; Electroporation ; methods ; Humans ; Neoplasms ; pathology ; therapy

OBJECTIVETo study the role of catecholamine(CA) in the mechanism of bio-effect of electromagnetic irradiation.

METHODSThe contents of norepinephrine (NE), epinephrine (E) and dopamine (DA) in serum and hippocampus of rats at 0, 8, 24, 48 hours after electromagnetic irradiation were measured by using high performance liquid chromatography with electrochemical detector(HPLC-ECD), and the influence of two kinds of shelter on CA was studied.

RESULTSThe levels of CA in serum and hippocampus increased obviously in an instant, decreased at 8 h and increased significantly again at 24 h after irradiation without shielding irradiation. But at 48 h, the levels of NA, DA in hippocampus were still higher and the serum's NA, DA were not different from the control. After irradiation with whole body shielding, the levels of CA had no changes. The contents of CA increased significantly only at 24 h after irradiation by 65 W/cm2 electromagnetic wave with trunk shielding. After irradiation by 129 W/cm2 with trunk shielding, the change of CA were similar to that of no shielding.

CONCLUSIONCA may take part in the injury to central nervous system and cardiovascular system after electromagnetic irradiation. And the injury to central nervous system may sustain longer than that of cardiovascular system. The protective effect of whole body shielding is the best, while trunk shielding may have some protective effect following lower and middle power electromagnetic wave. The most important protective measure is to shield the head.

Animals ; Catecholamines ; analysis ; blood ; Chromatography, High Pressure Liquid ; Electrochemistry ; Electromagnetic Phenomena ; Hippocampus ; chemistry ; radiation effects ; Rats