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1.
J Environ Radioact ; 166(Pt 2): 321-340, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27105766

RESUMO

It is estimated that exposure to radon in Norwegian dwellings is responsible for as many as 300 deaths a year due to lung cancer. To address this, the authorities in Norway have developed a national action plan that has the aim of reducing exposure to radon in Norway (Norwegian Ministries, 2010). The plan includes further investigation of the relationship between radon hazard and geological conditions, and development of map-based tools for assessing the large spatial variation in radon hazard levels across Norway. The main focus of the present contribution is to describe how we generate map predictions of radon potential (RP), a measure of radon hazard, from available airborne gamma ray spectrometry (AGRS) surveys in Norway, and what impact these map predictions can be expected to have on radon protection work including land-use planning and targeted surveying. We have compiled 11 contiguous AGRS surveys centred on the most populated part of Norway around Oslo to produce an equivalent uranium map measuring 180 km × 102 km that represents the relative concentrations of radon in the near surface of the ground with a spatial resolution in the 100 s of metres. We find that this map of radon in the ground offers a far more detailed and reliable picture of the distribution of radon in the sub-surface than can be deduced from the available digital geology maps. We tested the performances of digital geology and AGRS data as predictors of RP. We find that digital geology explains approximately 40% of the observed variance in ln RP nationally, while the AGRS data in the Oslo area split into 14 bands explains approximately 70% of the variance in the same parameter. We also notice that there are too few indoor data to characterise all geological settings in Norway which leaves areas in the geology-based RP map in the Oslo area, and elsewhere, unclassified. The AGRS RP map is derived from fewer classes, all characterised by more than 30 indoor measurements, and the corresponding RP map of the Oslo area has no unclassified parts. We used statistics of proportions to add 95% confidence limits to estimates of RP on our predictive maps, offering public health strategists an objective measure of uncertainty in the model. The geological and AGRS RP maps were further compared in terms of their performances in correctly classifying local areas known to be radon affected and less affected. Both maps were accurate in their predictions; however the AGRS map out-performed the geology map in its ability to offer confident predictions of RP for all of the local areas tested. We compared the AGRS RP map with the 2015 distribution of population in the Oslo area to determine the likely impact of radon contamination on the population. 11.4% of the population currently reside in the area classified as radon affected. 34% of ground floor living spaces in this affected area are expected to exceed the maximum limit of 200 Bq/m3, while 8.4% of similar spaces outside the affected area exceed this same limit, indicating that the map is very efficient at separating areas with quite different radon contamination profiles. The usefulness of the AGRS RP map in guiding new indoor radon surveys in the Oslo area was also examined. It is shown that indoor measuring programmes targeted on elevated RP areas could be as much as 6 times more efficient at identifying ground floor living spaces above the radon action level compared with surveys based on a random sampling strategy. Also, targeted measuring using the AGRS RP map as a guide makes it practical to search for the worst affected homes in the Oslo area: 10% of the incidences of very high radon contamination in ground floor living spaces (≥800 Bq/m3) are concentrated in just 1.2% of the populated part of the area.


Assuntos
Poluentes Radioativos do Ar/análise , Contaminação Radioativa do Ar/estatística & dados numéricos , Monitoramento de Radiação/métodos , Radônio/análise , Raios gama , Noruega
2.
J Environ Radioact ; 107: 68-77, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22326718

RESUMO

In recent years car-borne gamma spectrometry has expanded from its role as a geological survey platform to being a useful asset in searching for orphan sources and for surveying in the aftermath of an incident involving the release of radioactive materials. The opportunities for gaining practical experience in the field however are limited by cost considerations and practicability. These limitations are exacerbated by the fact that field data can differ significantly from data generated in the laboratory. As a means of exercising existing emergency measuring/surveying capability and introducing car-borne measurements to a larger group, a virtual exercise was devised. The exercise ORPEX (Orphan Sources and Fresh Fallout Virtual Exercise in Mobile Measurement) featured two typical emergency scenarios: a search for orphan sources and surveying to delineate fallout from a local release point. Synthetic spectral data were generated for point sources and inserted into genuine car-borne measurement data. Participants were presented with a typical software tool and data and were asked to report source locations and isotopes within a time limit. In the second scenario, synthetic data representing fallout from a local fire involving radioactive material were added to real car-borne data, participants being asked to produce maps identifying and characterising the regions of contamination. Fourteen individual organisations from seven different countries supplied results which indicated that for strong sources of isotopes with simple spectra featuring high energy peaks, location and identification was not a problem. Problems arose for isotopes with low energy signals or that presented a weak signal even when visible for extended periods. Experienced analysts tended to perform better in identification of sources irrespective of experience with mobile measurements whereas those with experience in such measurements were more confident in providing more precise estimates of location. The results indicated the need for the inclusion of less frequently encountered sources in field exercise related to mobile measurements.


Assuntos
Monitoramento de Radiação/métodos , Espectrometria gama/métodos
4.
7.
J Endocrinol Invest ; 4(4): 455-7, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7334186

RESUMO

Cytosol and nuclear estrogen receptors and cytosol progesterone receptors were measured in 17 primary breast tumors and compared with sex chromatin frequencies. In cases with sex chromatin frequencies of greater than 20% there were 7/7 tumors with cytosol estrogen and progesterone receptors, 6/7 with cytosol and nuclear estrogen receptors, and 6/7 with all 3 receptors. This high proportion of receptor positive cases was not observed at lower sex chromatin frequencies. Sex chromatin frequencies in all the cytosol estrogen and progesterone receptor positive tumors were significantly higher (p less than 0.05) than in the other groups. Our results suggest a possible association between the presence of steroid hormone receptors and sex chromatin frequencies of greater than 20%.


Assuntos
Neoplasias da Mama/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Cromatina Sexual , Neoplasias da Mama/genética , Citosol/análise , Humanos
8.
Acta Vitaminol Enzymol ; 3(1): 8-11, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7293873

RESUMO

In a short trial, 24 patients with Paget's disease of the bone were treated for 2 weeks with either ascorbic acid and calcitonin in combination, or with calcitonin alone. Pain relief was then assessed subjectively by the patients and classified as nil, some, or a marked reduction in pain. There were 11 patients in the group on combined therapy and 73% of them experienced pain relief, compared with 85% of the 13 patients in the group on calcitonin alone. In the patients who experienced pain relief, however, 62% of those on the ascorbic acid and calcitonin combination claimed a marked relief of pain compared with only 36% of the patients who responded to calcitonin alone. These results indicate that when calcitonin and ascorbic acid are used in combination they may provide an increase in the extent of pain relief, but do not increase the total proportion of patients actually obtaining relief. Urinary hydroxyproline excretion was reduced in the calcitonin treated group, but there was little change in the patients on the combined therapy.


Assuntos
Ácido Ascórbico/uso terapêutico , Calcitonina/uso terapêutico , Osteíte Deformante/tratamento farmacológico , Dor/tratamento farmacológico , Quimioterapia Combinada , Humanos
9.
Oncology ; 37(1): 30-2, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7350552

RESUMO

Current evidence indicates an association between oestrogens, sex chromatin frequency and X chromosome activation in relation to the activity of the enzyme glucose-6-phosphate dehydrogenase. We suggest that a similar association might apply to control the level of oestradiol receptors in breast tumours and present information supporting this hypothesis.


PIP: Evidence is presented which suggests that formation of estrogen receptor and activity of the "glucose-6-phosphate dehydrogenase enzyme are both X-linked functions, and this supposition is the basis for the contention that there is a similar association between the level of estradiol receptors in breast tumor tissue and the number of sex chromatin bodies/cell. The presence of sex chromatins, rather than hormone receptors, may be the key to etiology: breast tumors were divided into 3 groups based on sex chromatin levels of 1, 2, and 3, and the following relationships between sex chromatin bodies and estrogen receptors in human breast cancer were found: with 0,1 sex chromatin body/cell (n=7 tumors), 17% of the cells had sex chromatin bodies and 5 of the tumors were estrogen receptor positive and 2 were negative. With the number of sex chromatin bodies/cell at 0,1,2 (n=26 tumors), 28% of cells had sex chromatin bodies, and 5 tumors were estrogen receptor positive and 8 were negative. Increases in sex chromatin count, therefore, were associated with a higher proportion of estrogen receptor-negative tumors, indicating that X chromosome inactivation may be linked with reduced estrogen receptor formation. It is postulated that the gene regulating the level of estrogen receptor protein is on the X chromosome.


Assuntos
Neoplasias da Mama/genética , Neoplasias Hormônio-Dependentes/genética , Receptores de Estrogênio , Cromatina Sexual , Cromossomos Sexuais , Cromossomo X , Neoplasias da Mama/metabolismo , Feminino , Glucosefosfato Desidrogenase/metabolismo , Humanos , Neoplasias Hormônio-Dependentes/metabolismo
10.
Experientia ; 35(7): 911-2, 1979 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-477852

RESUMO

The plasma obtained from fed and starved lean, normal and obese women was estimated, by a radio-immunoassay method, for prostaglandins, owing to their implication in the regulation of adipose tissue lipolysis and the development of obesity. No significant differences were found due to nutritional status or body-build. However, a significantly higher plasma concentration of prostaglandins of the E-type than of the F-type, was found consistently. The very low levels of prostaglandins observed (a range of 0.10--0.15 ng ml-1 for E-type and a range of 0.05--0.07 ng ml-1 for the F-type) may be due, in part, to the activity of a plasmatic prostaglandin metabolizing system.


Assuntos
Obesidade/sangue , Prostaglandinas E/sangue , Prostaglandinas F/sangue , Jejum , Feminino , Humanos , Valores de Referência
12.
Acta Vitaminol Enzymol ; 32(1-4): 45-9, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-582875

RESUMO

Sixteen patients with painful Paget's disease of the bone were treated with high doses of ascorbic acid. Of these patients, 8 experienced lessening of pain within a period of 5 to 7 days after commencing the vitamin therapy. In 3 of these patients pain was completely abolished. Subsequent treatment with calcitonin caused improvement in most cases. There was little change in plasma alkaline phosphatase levels but the excretion of hydroxyproline was elevated following administration of the vitamin. The highest excretions were found in those patients who experienced complete relief of pain. In patients treated with calcitonin alone, the excretion of hydroxyproline was reduced and urinary levels of ascorbic acid dropped in parallel. It seems clear that ascorbic acid and calcitonin have different effects upon bone metabolism.


Assuntos
Ácido Ascórbico/uso terapêutico , Osteíte Deformante/tratamento farmacológico , Dor/tratamento farmacológico , Idoso , Fosfatase Alcalina/sangue , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/urina , Feminino , Humanos , Hidroxiprolina/urina , Masculino , Osteíte Deformante/sangue , Osteíte Deformante/complicações
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