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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↗
PubMed2006

[Radio wave and cryodestruction in the complex therapy of cervical lesions].

We have determined the effectiveness of cryodestruction and radio wave surgery during the treatment of background diseases of cervical lesions. To 52 patients with background diseases of cervical lesions the radio wave surgery has been performed and for 81 patients cryodestruction has been carried out, 65 patients got laser, anti-virus and immunomodulating therapy after cryosurgical treatment. The usage of radio wave surgery and cryodestruction helps to avoid unpleasant postoperative consequences such as pain, edema, infection and postoperative shock from loss of blood, which quite often arise after application of traditional methods of surgical operation. The advantage of cryodestruction and radio wave surgery at treatment of background diseases of cervical lesions in comparison with other invasive methods of treatment of given pathology is the absence of scars and preservation of cervical lesions' reproductive function. During the radio wave surgery operation the depth of destruction of tissues are being controlled by the adjustment of the device's capacity, which in our opinion is an advantage of radio wave method of treatment of cervical lesions' pathology in comparison with the method of cryodestruction.

Cervix Uteri↗
PubMed1970

Generation of radio waves in pulsars.

Pulsars generate radio waves by an unknown process which gives the highest volume emissivity known in astrophysics. The radiation forms a beam the width and polarization of which are independent of frequency. This article assembles the observational facts which any theory of emission must explain.

Journal Article↗
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↗
PubMed2005

Observation of radio-wave-induced red hydroxyl emission at low altitude in the ionosphere.

We report the discovery of radio-wave-induced red emission of OH Meinel rotation-vibrational bands at 629.79 nm. These are the first measurements of artificial aurora below 100 km. We believe that the 629.79-nm OH emission was due to radio-wave focusing by sporadic ionization clouds near 80-85 km altitude, thus giving a technique to visualize the low-altitude sporadic ionization and providing insight into ionospheric interactions at these low altitudes.

Journal Article↗
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↗
PubMed2006

Public exposure to radio waves near GSM microcell and picocell base stations.

Exposures of the general public to radio waves at locations near 20 randomly selected GSM microcell and picocell base stations in the UK have been assessed in the context of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Compliance distances were calculated for the antennas of the base stations from their reported radiated powers. Under pessimistic assumptions that would maximise exposures, the minimum height at which the general public reference level could potentially be exceeded near any of the base station antennas was calculated to be 2.4 m above ground level. The power densities of the broadcast carriers transmitted by the base stations have been measured and scaled to include all other possible carriers. Exposures were generally in the range 0.002-2% of the ICNIRP general public reference level, and the greatest exposure quotient near any of the base stations was 8.6%. Exposures close to microcell base stations were found to be generally greater than those close to macrocell base stations.

Cell Phone↗
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↗
PubMed2005

Creation of visible artificial optical emissions in the aurora by high-power radio waves.

Generation of artificial light in the sky by means of high-power radio waves interacting with the ionospheric plasma has been envisaged since the early days of radio exploration of the upper atmosphere, with proposed applications ranging from regional night-time street lighting to atmospheric measurements. Weak optical emissions have been produced for decades in such ionospheric 'heating' experiments, where they serve as key indicators of electron acceleration, thermal heating, and other effects of incompletely understood wave-particle interactions in the plasma under conditions difficult to replicate in the laboratory. The extremely low intensities produced previously have, however, required sensitive instrumentation for detection, preventing applications beyond scientific research. Here we report observations of radio-induced optical emissions bright enough to be seen by the naked eye, and produced not in the quiet mid-latitude ionosphere, but in the midst of a pulsating natural aurora. This may open the door to visual applications of ionospheric heating technology or provide a way to probe the dynamics of the natural aurora and magnetosphere.

Atmosphere↗
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↗