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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Risco de exposição à radiação ionizante em crianças e adolescentes participantes de um programa de controle da asma em comparação à população geral / Exposure risk to ionizing radiation in children and adolescents participating in an asthma control program compared to the general population

Lima, Letícia Guimarães Carvalho de Souza 09 June 2017 (has links)
Asma é uma doença de elevada prevalência e morbidade, constituindo-se um importante problema de saúde pública em todo o mundo. Muitos diagnósticos médicos por imagem dependem da utilização de raio X; entretanto, no caso da asma, o diagnóstico é clínico, particularmente na criança. Os pacientes são frequentemente submetidos a procedimentos radiológicos, preferencialmente o raio X de tórax. A escassez de dados na literatura referentes aos riscos da exposição à radiação ionizante em pacientes com asma e os possíveis benefícios relacionados à oportunidade de coleta de informações justificaram a investigação no programa municipal infantil de controle da asma de Ipatinga, Minas Gerais (Programa Respirar). Foi realizado estudo retrospectivo referente ao ano de 2014, com caso controle, do qual participaram 363 pacientes do Programa Respirar e número semelhante de controle, sem diferença sociodemográfica significativa entre os grupos. Encontramos que uma criança do grupo respirar tem 1,59 vez mais chance de realizar um raio X, e para o raio X de tórax essa chance aumenta para 6,56 vezes. A maioria dos raios X de tórax foi solicitada nas visitas aos serviços de urgência, mas 90% dos raios X realizados e laudados no grupo respirar e 84,2% do grupo controle revelaram resultado normal ou com alterações típicas, possibilitando o questionamento a respeito da indicação do exame. / Asthma is a disease of high prevalence and morbidity, constituting an important public health problem throughout the world. Patients are often submitted to radiological procedures, preferably the chest X ray. Many medical imaging diagnoses depend on the use of X ray, however, in the case of asthma, the diagnosis is clinical, particularly in the child. The scarcity of data in the literature regarding the risks of exposure to ionizing radiation in patients with asthma and the possible benefits related to the opportunity to collect information justified the investigation in the municipal infant asthma control program in Ipatinga, Minas Gerais (Programa Respirar). A retrospective study was carried out for the year 2014, with a control case involving 363 patients from the Programa Respirar and a similar number of controls, with no significant sociodemographic difference between the groups. We found that a child in the group respirar is 1.59 time more likely to have an X ray and for the chest X ray this chance increases to 6.56 times. The majority of chest X rays were requested at emergency department visits, but 90% of the X rays performed and lauded in the Programa Respirar and 84.2% of the control group revealed normal results or with typical alterations, making it possible to question the indication of the examination.
22

Radiační ochrana v pediatrii. / Radiation protection of pediatric radiodiagnostic

VÁLKOVÁ, Alena January 2018 (has links)
Due to the increase of number of ionizing radiation examinations in the pediatric population, it is important to focus on protecting them, as we assume that children have a long life ahead, and therefore the likelihood of a higher risk of ionizing radiation damage, where repeated use of ionizing radiation can cause irreversible changes of the organism. Therefore, the main objective is to evaluate and investigate the level of radiation protection both of professionals and of the general public.
23

Avaliação das doses resultantes de procedimentos radiodiagnósticos realizados em medicina veterinária e avaliação das doses secundárias de radiação espalhada no corpo clínico e nos proprietários dos animais / Evaluation of doses from radiodiagnotic procedures performed in veterinary medicine and assessing of the doses of secondary radiation in the medical staff and animal owners

Veneziani, Glauco Rogério 25 March 2013 (has links)
O objetivo primordial em radiologia veterinária é a produção de radiografias com qualidade diagnóstica, em uma primeira tentativa. Esse objetivo deve atender a três propósitos: (1) diminuir a exposição à radiação do paciente e trabalhadores; (2) diminuir o custo do estudo para o cliente e (3) produzir dados diagnósticos para rápida interpretação e tratamento do paciente. Esse trabalho teve por objetivo a determinação das doses em cães submetidos a radiografias de tórax e abdômen utilizando a técnica da dosimetria termoluminescente (TL). As doses de radiação foram avaliadas com a utilização de dosímetros termoluminescentes de sulfato de cálcio dopado com disprósio (CaSO4:Dy) e fluoreto de lítio dopado com magnésio e titânio (LiF:Mg,Ti). Os resultados obtidos indicam que é extremamente importante a avaliação das doses de radiação envolvidas em procedimentos diagnósticos de radiologia veterinária, para a avaliação das doses nos animais e para ser usado como um parâmetro para a monitoração individual dos proprietários de animais, que auxiliam no posicionamento, e para a proteção dos trabalhadores ocupacionalmente expostos nas Clínicas de Radiologia Veterinária. / The primary goal in veterinary radiography is to produce radiographs of diagnostic quality on the first attempt. This goal serves three purposes: (1) to decrease radiation exposure to the patient and veterinary personnel; (2) to decrease the cost of the study for the client; and (3) to produce diagnostic data for rapid interpretation and treatment of the patient. This work aimed to determine the doses in dogs submitted to chest and abdomen Xrays using the technique of thermoluminescence (TL) dosimetry. The radiation doses were assessed using thermoluminescent dosimeters of calcium sulphate doped with dysprosium (CaSO4:Dy) and lithium fluoride doped with magnesium and titanium (LiF:Mg,Ti). The obtained results indicate that is extremely important the assessment of radiation doses involved in veterinary diagnostic radiology procedures, to evaluate the delivered doses to the animals, to be used as a parameter in the individual monitoring of pets owners, who assist the animal positioning, and to protect occupationally exposed workers at the Veterinary Radiology Clinics.
24

Strålskydd för personal som arbetar inom Interventionell Radiologi

Lindgren, Johanna, Gustavsson, Erika January 2014 (has links)
Bakgrund: Trots en snabb utveckling av undersökningsmetoderna inom IR har inte strålskydden utvecklats i samma takt. Den joniserande strålning som förekommer på modaliteten kan medföra en hälsorisk för personalen därav finns det stråldosgränser att hålla sig inom för att minimera risken för yrkesrelaterade strålskador. För att förebygga risken för strålningsrelaterade skador är det viktigt att undersöka olika metoder av skydd för att optimera personalens strålsäkerhet.Syfte: Syftet med studien var att belysa metoder för att reducera stråldosen för personal verksam vid interventionell radiologi.Metod: Sökningarna av artiklarna genomfördes i databaserna CINAHL, PubMed och Scopus varav 13 studier valdes ut, kvalitetsgranskades samt analyserades kritiskt med utgångspunkt från en innehållsanalys.Resultat: Resultatet visade på 11 strålskyddsmetoder för personalen: blyförkläde med thyroideablyskydd, Suspended Personal Radiation Protection System, blyglasögon, blyhandskar, takfäst blyglas, golvbaserade blyglas, patientblyskydd, direktdigital dosimeter, avstånd till patienten genom automatisk kontrastspruta, vismut-bariumöverdrag samt erfarenhet och information.Konklusion: Trots att metoderna enskild reducerade stråldosen till personalen skulle det kunna vara mer effektivt att kombinera olika strålskydd för bättre reduceringseffekt. Genom resultatet anser författarna att fortsatt forskning krävs inom utvecklandet av nya strålskydd som är mer ergonomiska mot personalen samt hur strålskydden påverkar patienterna både fysiskt och psykiskt. / Background: Despite the fast development of examination methods in IR, the development of the radiation protections has not been as rapid. Ionizing radiation that occurs in the modality can be a threat to the personnel of which there are radiation dose limits to keep within in order to minimize the risk of occupational radiation damage. In order to minimize the risk of occupational radiation damage, it is of importance to explore different methods to optimize the radiation protection for the personnel.Purpose: The aim of this study was to illuminate methods to reduce the radiation dose to personnel working in interventional radiology.Method: Searches were conducted in the databases CINAHL, PubMed and Scopus from which 13 studies were selected, viewed and analyzed with basis from a content analysis.Results: The results showed 11 different radiation protection methods for the staff were identified and those were: lead apron with a thyroid lead shield, Suspended Personal Radiation Protection System, leaded eyeglasses, leaded gloves, ceiling suspended leaded shield, rolling leaded shield, patient lead shield, real-time dosimeter, distance to the patient through an automatic power injector, bismuth - barium shielding and experience and information.Conclusion: Although the methods individual reduced radiation dose to the personnel, it might be more efficient to combine the various radiation protections for better reduction effect. The authors recommend that further research is required in the development of new radiation protection that is more ergonomic to the personnel and how the radiation shields affects patients both physically and psychologically.
25

Avaliacao de dosimetros termoluminescentes empregando objetos simuladores equivalentes a agua para aplicacao na dosimetria de feixes clinicos de eletrons / Evaluation of thermoluminescent dosimeters using water equivalent phantoms for application in clinical electrons beams dosimetry

BRAVIM, AMANDA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:28:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:12Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
26

Odhad průměrné radiační zátěže při lékařském diagnostickém ozáření / Assessment of the average radiation exposure from medical diagnostics

BALTA, Petr January 2016 (has links)
The diploma thesis dealt with the theme of "Assessment of the average radiation exposure from medical diagnostics" is divided into two main parts. The first one is concerned with the various measurement of radiation dose during diagnostic medical radiation. The second one is focused on radiation dose optimization during diagnostic medical radiation. With increasing of the collective effective dose in population, we should consider the importance of radiation protection during diagnostic medical radiation and accuracy of effective dose estimate that is used during individual medical examinations. On the basis of these estimates, it is necessary to determine the medical theory of radiation protection and to gain control over radiation dose and optimization of diagnostic medical radiation somehow. The theoretical part describes the kinds of ionizing radiation and their biological effects on organism. This part follows the chapter devoted to radiation protection and legal framework of the Czech Republic that is related to the topic: the application of ionizing radiation, mainly the Act No. 18 /1997 Coll. on Peaceful Utilisation of Nuclear Energy and Decree of the SÚJB No. 307 /2002 Coll., on Radiation Protection. There are discussed also the particular principles of protection against radiation. Afterwards, in the theoretical part, the quantities and the units used by radiodiagnostics and nuclear medicine are described. They are needed to know for the following determination and the estimate of dose amount absorbed by human organism. The conclusion of the theoretical part treats the methods used for estimate of dose received during medical examination and new trends in radiation management of individual patients. In the diploma thesis, there are set up two research questions. The thesis has been looking for the answers by its own research. The first research question is, if the current way of measurement of radiation dose is sufficient. The second one has been asking for manners of access allowed the decreasing of dose for patients regarding to registered effective dose. On the basis of these defined research questions, the basic aims have been set up to consider the application of individual methods of dose evaluation during medical radiation, to determine, from the registered values, probably the most exact method for evaluation of radiation dose and to deduce the probability of stochastic effects formation conditioned by radiation. The research was performed with two groups of patients that were undergone skiagraphic examination of lungs and examination of stomach by computed tomography (CT). The research devoted to skiagraphic examination of lungs was dealt with women suffering by similar body constitution. The results of measured effective dose of these patients were compared, and the manner of measurement and influencing of final absorb dose in the mammary gland were presented. The relation of individual projections towards probability of cancer birth conditioned by radiation was demonstrated. For comparison and setting up the most exact method, the first group was measured by the most available and the most common way used in clinical practice. PCXMC and ImPACT CT software are the most applying methods in clinical practice. As the most available method, standardize values and the procedure from the Bulletin of the Ministry of Health for Radiation Physics were applied. The final effective doses were compared with the local and national diagnostic referential levels in order to set up the correct procedure of radiation protection. The second researched group of patients undergone stomach examination performed by computed tomography (CT). The final effective doses of these patients were compared according to ICRP 60 and ICRP 103. Just as in the first group, there were compared two methods of measurement, the most available and the most applying in the practice.
27

Análise de requisitos normativos para o desenvolvimento e a implementação de um sistema de gestão da qualidade em instalações e atividades nucleares brasileiras / Analysis of normative requirements for the development and implementation of a quality management system in Brazilian nuclear installations and activities

KIBRIT, EDUARDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:46Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:54Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
28

Proposta de procedimentos para evitar erros em radioterapia baseados em lições aprendidas de exposições acidentais

BUENO, GISELLE O.V. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:29Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:04Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
29

Aspectos bioquimicos da acao de imunomoduladores na sobrevida de camundongos irradiados com radiacao gama de Co-60

AGUDO GARCIA, NELIDA L. DEL M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:31:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:44Z (GMT). No. of bitstreams: 1 01398.pdf: 1282633 bytes, checksum: 0403326b9b8a10fdcdec982e4f99fa99 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
30

Sistema de medição câmara de ionização-eletrômetro para ensaios de proteção radiológica em equipamentos de raios X para procedimentos intervencionistas / Ion chamber-electrometer measurement system for radiation protection tests in X-ray equipments for international procedures

BOTTARO, MARCIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:02Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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