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At least 163 records · Page 9Linked to original sources
PubMed2001

Development of a novel plant system as biosensor for detecting environmental hazards and bioactive molecules through distinct responses.

Currently, chemicals are used excessively in medicine, industry, and agriculture throughout the world. Because of the current rise in environmental pollutants and hazardous exposures of human beings, there is an imperative need for monitoring the environment for biosafety. In addition, the importance of natural products with novel activity for drug or agrochemical scopes is being more and more realized. We report on a novel test system that can act as biosensors for detecting useful compounds while simultaneously monitoring or forecasting the biohazard exposure of organisms to chemicals as well as to physical factors in a given environment. Using different compounds and factors with known biological and cytotoxic activities, a detail plant test procedure has been developed that can be used in detecting and analyzing the value and/or danger of any given compound or treatment, including cell division inhibition, cytotoxicity, growth inhibition, and anticancer activities. The method provides a highly efficient single biosensor system that can replace several individual biotesting procedures. This plant assay procedure is a highly sensitive system for monitoring physical stress factors in the environment, including ionizing and nonionizing radiation. The procedure can be followed throughout the year because of the rapid growth rate of the plant used and its regeneration in ambient conditions. Therefore, the described system is highly useful to thoroughly monitor the environment and detection of new chemicals/compounds.

Biosensing Techniques↗
PubMedDate not supplied

Didactic and clinical competency.

Because the ARRT's mission is to recognize individuals "qualified" in the use of ionizing and nonionizing radiation for medical imaging and radiation therapy, it falls upon the ARRT to define what "qualified" means. The goal of the competency project was to further refine our definition of what qualified means as it relates to educational preparation and to incorporate that refined definition into existing eligibility requirements. Certification requirements should be both specific and public. The competency requirements accomplish this for ARRT's educational eligibility requirements and will help advance certification as well as education in the profession.

Clinical Competence↗
PubMed2000

[Reconstruction technology of electrical impedance tomography].

Electrical impedance tomography(EIT) is a new medical image technology; it has the advantages of low cost, nonionizing radiation, and the capability of production images of physiological function dynamically. EIT reconstruction has always been a project of importance to EIT researchers. In this paper, a review of the development of EIT reconstruction is presented.

Algorithms↗
PubMedDate not supplied

[The role of the thyroid hormones in regulating chromosomal resistance to microwave exposure].

The mutagenic effect of microwaves (2450 MHz, 500 mu W/cm2, 30 days, 7 h/day) on rats was shown to decrease under the influence of thyroxine (2.5 mu g/100 g) administered over a two-week period. The major role of thyroid hormones in the formation of the antimutagenic effect of nonionizing radiation (2450 MHz, 10 mu W/cm2, 30 days, 7 h/day) was confirmed by the experiments with the parathyroid gland being removed.

Animals↗
PubMed1992

Diagnostic imaging of adnexal masses. A review.

The application of diagnostic imaging modalities in the management of adnexal masses is reviewed. Nonionizing radiation techniques (ultrasound and magnetic resonance) are particularly important in pregnant and pediatric patients. Special consideration is given to imaging adnexal masses during reproductive development and senescence.

Adnexal Diseases↗
PubMedDate not supplied

[The participation of thyroid hormones in modifying the mutagenic effect of microwaves].

The mutagenic effect of microwaves (2,450 or 2,750 MHz, 500 microW/cm2, 30 days, 7 h a day) increases with both low and high thyroid hormone content in rats. This indicates that normal functioning of the thyroid gland is an important condition for the stabilization of chromosome integrity under the effect of nonionizing radiation of microwaves.

Animals↗
PubMed1989

[The effects of space flight factors on the central nervous system. Structural-functional aspects of radio-modifying action].

The monograph has been dedicated to the analysis of structural and functional changes in the central nervous system of the experimental animals exposed to the isolated and combined effects of space flight factors. There have been shown many changes, which took place in the various anatomic-physiological formations of the brain, and evaluated their significance in organism's responses to the effects of ionizing and nonionizing radiation, hyperoxia, hypoxia, accelerations, vibrations and combined effects of some of those factors. The synergistic, antagonistic and cumulative (simple addition) effects of the investigated stressors along with the radiation factor on the CNS have been stated. This review is prescribed for the specialists in space biology, for physiologists, pathophysiologists, biochemists, radiobiologists and physicians.

Acceleration↗
PubMed1987

Occupational cancer.

Cancer resulting from occupational exposure is now receiving major attention, focusing on identification, regulation, and control of cancer-causing agents. Such cancer can result from exposure to chemicals and ionizing and nonionizing radiation. Extended exposure (often years) and an extended latent period of perhaps decades may intervene before tumor appearance. Although the actual extent of occupational cancer is in debate, estimates have ranged from 4 to 15 per cent of all cancer.

Humans↗
PubMed1988

Electromagnetic-field exposure and cancer.

Electromagnetic fields are a ubiquitous part of man's environment. Natural sources of energy have been present, and possibly have contributed to the processes of the evolution of living forms. In very recent time, however, exploitation of the properties of the electromagnetic spectrum, has added variables in intensity, frequency, modulation frequency, and alterations in contributions of electrical and magnetic components. Biological impact has been little studied and poorly defined. Animal carcinogenesis studies and human epidemiological data indicate that exposure to nonionizing radiation can play a role in cancer causation. Numerous effects at the physiological and biochemical level have been reported; many are of such a nature that a relationship to the causation of neoplastic transformation can rationally be hypothesized. Many bioeffects of electromagnetic fields can be adequately and economically explained in terms of heat effects alone. However, observations of frequency-, pulse form or modulation-, and intensity-specificity as well as effects opposite to that known for temperature-rise, imply direct interaction of radiant energy with biomolecules. The possibility of such direct interaction has been shown in quantum mechanical models.

Animals↗
PubMed1984

Whole-body hyperthermia induction techniques.

Currently, there are three techniques used for delivery of whole-body hyperthermia. The simplest of these is direct contact between skin and some surrounding fluid. The surrounding fluid can be either water, wax, air, or other fluid medium; heat is transferred from the surrounding fluid to the body surface. Vessels in the skin surface transfer heat to the perfusing blood, which uniformly distributes it throughout the body. The second technique uses irradiation of the body surface with nonionizing radiation to deliver heat to the first few cm from the surface. This heat can be picked up by local blood perfusion and distributed throughout the body. One advantage of this method over direct contact methods is that heat is deposited throughout the first few cm and therefore temperature increases at the surface are lower. The third technique is extracorporeal perfusion which seems the most promising method for delivery of whole-body hyperthermia. This allows for greater control of central temperature via rapid change in temperature of blood passing through the external heat exchanger. The increased ability to control temperature resulting from this advanced instrumentation allows accurate delivery of whole-body hyperthermia. This permits comparison studies of therapeutic effectiveness.

Clothing↗
PubMed1983

Ultrasonography and computed tomography in the evaluation of the acutely ill pediatric patient.

The use of diagnostic ultrasonography and CT in the investigation of the acutely ill pediatric patient has been steadily increasing because of the relative noninvasiveness of these imaging modalities and because of improvements in resolving capabilities and scanning speed of the latest equipment. In the examination of the pediatric patient, special emphasis must be given to immobilization, sedation, or both in those children too young or too ill to cooperate. Close monitoring and observation of the child throughout sedation is important and requires special personnel and equipment. The usual indications are the search for an abscess or occult infection, trauma, and acute renal failure. Because ultrasonography uses nonionizing radiation and is less expensive, it is usually the initial modality of choice for evaluating the pediatric patient. CT is reserved for situations in which greater anatomic detail and lack of compromise by the presence of bowel gas or bone are necessary. These situations include multiple abscess collections, particularly interloop abdominal abscesses, mediastinal masses and collections obscured by overlying lung, osteomyelitis, older patients with meningomyelocele and with spinal deformity when evaluating the urinary tract, and major multiorgan abdominal trauma.

Abdominal Injuries↗
PubMed1983

Accidental industrial laser burn of macula.

A 20-year-old graduate student in physics was struck in the left eye by light from a dye laser. The injury resulted in rapid and profound loss of central visual acuity in the affected eye. Over the course of six months after the injury the corrected central vision improved to 20/25. Accidental retinal injuries due to laser light are discussed, as is the effect of nonionizing radiation on the retinal tissues.

Adult↗
PubMed1982

Environmental pollution: the experimental and the human approach.

Thirty years have elapsed since laws preventing large scale pollution have begun to be made and enforced in industrial countries. Due partly to economic considerations, the actual methodology for the evaluation of health risks is now beginning to be considered. If the routine experimental and epidemiological investigations are complementary, their use, which needs respective delays of 4-5 and 20-30 years, is not adopted to determine the health effects of new chemicals or novel energies. To make up for these deficiencies, especially concerning the screening of carcinogenic and mutagenic potentials of chemicals, short in vitro tests have been developed, but they have not yet proved to be reliable. Among several investigational needs, the psychophysiological aspects of environmental pollution and the long-term effects of several kinds of nonionizing radiations, which more and more invade our environment, ought to be considered.

Environmental Pollutants↗
PubMed1995

The use of MR contrast agents in the evaluation of disease of the spine.

In the last decade, magnetic resonance (MR) of the spine has become the imaging modality of choice, superseding both computed tomography (CT) and myelography, for the evaluation of a broad spectrum of disease entities. The capability for multiplanar imaging, the use of nonionizing radiation, and the ability to obtain a myelographic-like image (without intrathecal contrast injection) all provide distinct advantages. This article reviews the current applications of intravenous contrast media in MR for evaluation of the spine and its contents. In many instances, contrast enhancement plays a valuable role in developmental disease, trauma (e.g., disk herniation, both before and after surgery), infection, vascular disease, neoplasia, degenerative disease (e.g., neurogenic claudication), and demyelinative processes (e.g., multiple sclerosis).

Contrast Media↗
PubMed1994

[The hygienic protective area of the Kaliakra Medium-Wave Radio Station].

A polemics on the ecological expedience of the transmitting station "Kaliakra", which is in the process of building, was held. The two opposing sides in the diaput are OOD "Bulgarian Posts and Power-line Communication" and the community of village Balgarevo, district of Varna. The ecological aspect of the project is very well known in the Ministry of the Environment and the Ministry of Public Health, as well as in the National Center of Hygiene, Medical Ecology and Nutrition. The latter has given an expert attitude for the hazardous zones around the site. As a result of this polemics is the delay of the building, i.e. blocking investments and missed opportunities, because of not realized exploitation. Stating the above we would like to expand the competent forum of the engaged in the problem. For this purpose we are ready to discuss with the participants in the Conference the methods and results of the calculations, as well as the normative basis, which were used in determining the hazardous zone. The control calculations point out, that the level of the electromagnetic exposure of the population in the district will be lower than the allowable values, which are given both in the Bulgarian State Standards and the foreign standard documents for hygiene control of nonionizing radiation.

Bulgaria↗
PubMed1994

Radiological measurements in patellofemoral disorders. A review.

This paper analyzes some of the radiologic measurements used in the diagnosis and management of patellofemoral disorders. Measurements such as condylar width and height and patellar height from the true lateral view are helpful to determine the type and severity of intercondylar dysplasia. Skyline views provide information on the type and degree of patellar subluxation and dysplasia, especially of the medial aspect of the trochlear groove. In asymptomatic subjects, the trochlear angle does not exceed 140 degrees, and the lateral medial intercondylar ratio in dysplasia is > 1.7. Scanograms specifically assess the longitudinal axis of the lower limb. Computed tomography (CT) measurements for patellar subluxation do not provide significant additional information over that provided by skyline views. The average distance between the anterior tibial tuberosity and the trochlear groove is normally 13 mm, and a distance > 20 mm associated with knee pain should probably warrant surgery. Because of multiplanar facilities and exposure to nonionizing radiations, magnetic resonance imaging is progressively replacing CT scanning for quantitative and qualitative measurements, at least in a research environment. Its use in routine clinical practice is not yet warranted, given its high costs.

Femur↗
PubMed1993

Health hazards of nursing: identifying workplace hazards and reducing risks.

Nurses often work in settings in which they may be exposed to a wide array of psychosocial, chemical, biological, and physical hazards. The authors outline several ways in which occupational exposures occur and the general process for reducing or preventing workplace hazards. Several commonly encountered workplace hazards and their potential health risks are identified and discussed. Specific health hazards that are addressed include the chemical hazards of antineoplastic and antiviral drugs; the biological hazards of human immunodeficiency virus, hepatitis B, herpes viruses, rubella, and tuberculosis; and the physical hazards of noise and ionizing and nonionizing radiation. The authors suggest specific preventive measures that nurses can take to make their workplaces safer.

Female↗