PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “RADIO WAVES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2001

Possible electromagnetic interference with electronic medical equipment by radio waves coming from outside the hospital.

Electromagnetic interference (EMI) with electronic medical equipment by radio waves from mobile telephone handsets has been reported and is currently receiving wide attention. The possibility of EMI with electronic medical equipment by radio waves coming into the hospital has also been pointed out. But so far, there are no reports measuring the frequency distribution of electric field intensity induced by incoming radio waves. Therefore, we measured electric field intensity induced by radio waves coming into our 11-floor hospital, which was under construction. The maximum intensity observed was about 200 V/m at 2.79 GHz, from airport surveillance radar waves. The maximum intensity induced by radio waves from cellular phone base stations was 1.78 V/m. These data show that various frequencies of radio waves are common in this urban area, and that they induce strong electricfield intensity. This strong electric field intensity might cause EMI with electronic medical equipment. Measurement of the electromagnetic environment should be done by each hospital in urban areas to prevent EMI with electronic medical equipment.

Electric Power Supplies↗
PubMed1986

Rewarming in immersion hypothermia: radio-wave and inhalation therapy.

Anesthetized random source dogs were cooled by ice water immersion (1 degree C) to a stable core temperature of 25 degrees C, and subsequently rewarmed with warm humidified inhalation (43 degrees C, 450 cc of min ventilation/kg), radio wave induction hyperthermia (4-6 W/kg) or both therapies simultaneously. The mean time required for core rewarming to 30 degrees C was 262 +/- 29 min for humidified ventilation, 68.5 +/- 6 min for radio wave therapy (P less than 0.01), and 74.8 +/- 12 for both therapies combined (P less than 0.3 vs. radio wave). There was no tissue damage with these protocols. These data suggest radio wave heating alone is the most rapid non-invasive method for core rewarming in immersion hypothermia.

Animals↗
PubMed1999

The penetration characteristic of radio wave frequencies from oral cavities.

Recently many radio telemetry systems have been inserted into oral cavities and have been used to send data to receivers. Although various frequencies were used in those systems, there has been no report about the most effective penetrative frequency in the human body. In this study, we observed the penetration of radio waves from oral cavities and compared the efficiency of different frequencies. We selected 11 edentulous persons as subjects and the frequencies ranged from 1 to 150 MHz. Although the attenuation gradually increased with the increase of frequency in most cases, we observed that there were effective resonance-like frequencies in three subjects and the frequency differed from person to person. This phenomenon was only observed when receiving antennas were set beside the mouth and not observed when the antennas were set about 1 m away from subjects. Therefore, it is considered that this phenomenon was produced by the relationship between the transmitting antenna and the receiving antenna. This result suggested that there were effective resonance-like frequencies in the case of radiation from edentulous oral cavities.

Aged↗
PubMed1987

Rewarming in accidental hypothermia: radio wave versus inhalation therapy.

Anesthetized random-source dogs were cooled by refrigeration (3 C) to a stable core temperature of 25 C, and subsequently were rewarmed with warm, humidified inhalation (43 C, 450 mL of minute ventilation per kilogram) or radio frequency induction hyperthermia (4 to 6 watts/kg). The mean time required for core rewarming to 30 C was 231 +/- 3 minutes for warm, humidified ventilation and 106 +/- 32 minutes for radio wave therapy (P less than .01). These data suggest that radio wave heating is a more rapid noninvasive therapy for core rewarming of accidental hypothermia.

Animals↗
PubMed1992

[Dosimetry in setting practical hygienic standards for radio-wave irradiation].

In dosimetric approach to the hygienic norm setting of radio waves adequate metrological basis is required. Joint investigations, carried by physicists and hygienists helped solve the new medical and technical problems, connected with the creation of individual dosimeters and indicators, monitor the hygienic norms of superhigh frequency electromagnetic waves. The devices are small, light, with autonomic power supply and digital indication of current exposure dose. The devices are supposed to give signals (light, sound) if the individual hygienic levels of superhigh frequency electromagnetic waves are surpassed.

Health Physics↗
PubMed1984

Comparison of rewarming by radio wave regional hyperthermia and warm humidified inhalation.

Anesthetized random source dogs were cooled by ice water immersion to a stable core temperature of 25 degrees C and subsequently rewarmed with warm humidified inhalation (43 degrees C, 450 cc of min ventilation X kg-1) or radio-frequency induction hyperthermia (4-6 watts X kg-1). The mean time required for core rewarming to 30 degrees C was 280 +/- 114 min for ventilation and 58 +/- 13 min for radio wave therapy (p less than 0.001). There was no evidence of tissue damage with either modality. These data suggest radio wave heating is superior to warm humidified inhalation therapy for core rewarming of rapidly induced immersion hypothermia.

Animals↗
PubMed1985

Controlled comparison of radio wave regional hyperthermia and peritoneal lavage rewarming after immersion hypothermia.

Anesthetized random source dogs were cooled by ice-water immersion to a stable core temperature of 25 degrees C and subsequently rewarmed with normal saline peritoneal lavage (43 degrees C, 175 ml/kg/hr) or radio frequency electromagnetic-induced regional hyperthermia (4-6 watts/kg). The mean time required for core rewarming to 30 degrees C was 183 +/- 79 minutes for lavage and 58 +/- 13 minutes for radio wave therapy (p less than 0.01). There was no evidence of tissue damage with either modality. These data suggest radio wave regional hyperthermia is superior to peritoneal lavage for core rewarming of rapidly induced immersion hypothermia.

Animals↗
PubMed1990

[Systematic analysis of the state of man exposed to radio wave irradiation for a long time].

A complex examination was made of 72 men--short-wave (3-30 MHz) radio equipment controllers. Two parallel control groups of 70 people all in all were examined. No regular changes in the dynamics of amplitude-frequency characteristics of electroencephalogram, associated with the length of service, were observed. The number of subjective complaints from people in contact with radiofrequencies increased with an increase in the length of service. The role of certain clinico-physiological parameters of the organism in the process of adaptation to electromagnetic radiation was quantitatively assessed with the use of status-metry technique; in particular, a decrease in the functional activity of the right hemisphere brain structures, aggravating with the length of service, was observed.

Adult↗
PubMed1993

[Non-hysteroscopic thermodestruction of the endometrium using radio waves in the treatment of menorrhagia].

OBJECTIVE: To test non-hysteroscopic thermodestruction of the endometrium for safety and efficiency. DESIGN: Prospective pilot study from February 1991 to July 1992. SETTING: University Hospital Nijmegen. PATIENTS AND METHOD: There were 68 patients aged 30-55 years with menorrhagia, who did not want children but wished to retain the uterus. There were two patients with a subserous myoma but with a normal uterine cavity. Patients with hypergonadotropism, a markedly enlarged uterus, abnormalities at cytological examination of the cervix, adnexal lesions, prolapse, intrauterine lesions and coagulation disorders were excluded. By way of preparation, danazol was administered for 4 weeks before the intervention (36 patients). Three patients with side effects were given lynestrenol. From January 1992, an LH-RH analogue was administered (29 patients) for 6 weeks prior to the intervention or in the patients with a subserous myoma for 12 weeks. Thermodestruction of the endometrium by means of radio waves was carried out according to a standard protocol under general or epidural spinal anaesthesia. The intracavitary temperature measured was 62-65 degrees C, mean duration of the treatment 20 minutes. RESULTS: The patients were discharged 10-24 hours after the intervention. A non-disturbing watery discharge of 3-6 weeks' duration was reported. Normal activities were resumed after one week. Success (duration of follow-up 3-21 months) was defined as amenorrhoea (6 patients; 9%) or a markedly reduced menstruation or duration of menstruation (48 patients; 70%). Six patients (9%) reported no improvement and of eight patients (12%) with slight, unsatisfactory improvement three were treated again, with success (4%). During the trial period the method was further adjusted and perfected. There were no complications. CONCLUSION: This preliminary experience shows that thermodestruction with radio waves is simple, safe and efficient.

Adult↗
PubMed2004

Measurement of the solar gravitational deflection of radio waves using geodetic very-long-baseline interferometry data, 1979-1999.

We used very-long-baseline interferometry (VLBI) to measure the deflection by the Sun of radio waves emanating from distant compact radio sources. This bending is characterized in the parametrized post-Newtonian formalism by gamma, which is unity in general relativity. Using a large geodetic VLBI data set, we obtained gamma=0.9998(3)+/-0.0004(5) (estimated standard error). We found no systematic biases from our analysis of subgroups of data.

Journal Article↗
PubMedDate not supplied

[Morphological and functional characteristics of hemopoiesis during the combined use of cyclophosphane with millimeter-band radio waves of nonthermal intensity].

Material is presented on combined effects of mm-band radio waves and cyclophosphane on the hemopoietic system and inoculated tumor sarcoma-180. The role of the bone marrow truncal cells in the acceleration of regenerative processes and a two-fold increase of clonogenic activity of the bone marrow were determined in the combined group in comparison with the bone marrow of animals receiving just the preparation. The sensitizing effect of mm-waves in combination with cyclophosphane was distinctly manifested after two courses of administration of the preparation, leading to 85-100% resorption of the tumours without further relapses during the year of observation over the animals.

Animals↗
PubMed2003

Radio-wave exposure of the human head: analytical study based on a versatile eccentric spheres model including a brain core and a pair of eyeballs.

A versatile eccentric-spheres model of the human head is used in this paper to investigate radio-wave absorption. Numerical results, obtained by use of an exact analytical solution, are presented for the total, percentage, and gram-specific absorption. Interest is mainly in the brain and in the eyes of an adult or an infant head. Our model comprises a host sphere and several spherical inclusions, all concentrically stratified with respect to their own center. Any number of inclusions and any number of concentric layers for the host sphere and each one of the inclusions can be considered. Excitation is provided either by a plane-wave or by a nearby electric dipole. The analytical solution is obtained by use of the indirect-mode matching method. The theory of this paper and the accompanying computer code constitute a versatile tool for analytical studies of cellular-phone interactions with the human head. Specific absorption rate maps in a horizontal cross section of the head model manifest the existence of hot spots in the eyes and near the center of the brain.

Adult↗
PubMedDate not supplied

Failure of chronic exposure to nonthermal FM radio waves to mutate Drosophila.

A stock of Drosophila sc VI - YS/y ac oc ptg - YL/y ac oc ptg - YL/y sc S1 B In49 ct ns v sc8 that accumulated the recessive lethals on the X chromosome was exposed to a frequency of 98.5 MHz (wave length 3.35 m) and a field strength of 0.3 V/m. The flies were kept near the base of the 300-ft antenna of a 50,000 watt transmitter for 32 weeks. There was no significant difference in the percentage of lethals between the stock exposed to 4,020 hours of nonthermal FM radio waves and the controls.

Animals↗
PubMed1990

Treatment of verrucae via radio wave surgery.

Verrucae are common skin lesions seen mainly in younger patients. They often are seen on the plantar surface of the foot. Many different types of treatments have been used over the years, with varying levels of success. The authors present a thorough review of previous treatments and present a new and effective method of surgical excision using radio wave technique. The success of this treatment is high, and the postsurgical pain and complication level is minimal.

Adolescent↗