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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.
1

Human mammary cell survival following ionizing radiation

Cathers, Lorraine Evelyn. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Dosimetric investigation of electron arc therapy delivered using Siemens electron arc applicator with a trapezoidal aperture : a thesis submitted in partial fulfilment of the requirements for the degree of Master [of Science] in Medical Physics in the University of Canterbury /

Xing, Aitang. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (p. 108-119). Also available via the World Wide Web.
3

The effects of radiation on cells in vivo a rat mammary gland model /

Gould, Michael Nathan, January 1977 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references.
4

Avaliação do efeito radioprotetor da vitamina "E" em glandulas parotidas de ratos : uma analise morfometrica / Evaluation of radioprotective effect of vitamin E in parotid gland of rats : morphometric analysis

Gomes, Carolina Cintra, 1979- 12 August 2018 (has links)
Orientador: Solange Maria de Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba. / Made available in DSpace on 2018-08-12T21:44:01Z (GMT). No. of bitstreams: 1 Gomes_CarolinaCintra_M.pdf: 5143027 bytes, checksum: 4a53ca765bc6a44478ed5b30de142749 (MD5) Previous issue date: 2009 / Resumo: O objetivo neste trabalho foi avaliar, por meio de análise morfométrica, o efeito radioprotetor da vitamina E em glândulas parótidas de ratos. Foram utilizados 90 ratos machos (Rattus norvegicus, Albinus, Wistar), os quais foram divididos aleatoriamente em cinco grupos experimentais: Óleo, correspondendo aos animais que receberam óleo de oliva; Óleo Irradiado, grupo no qual os animais receberam óleo de oliva e foram irradiados com dose única de 15 Gy de radiação gama na região de cabeça e pescoço; Irradiado, em que os animais foram irradiados com dose única de 15 Gy de radiação gama; Vitamina E, grupo em que os animais receberam solução de acetato de alfa-tocoferol (vitamina E), mas não foram irradiados e Vitamina E Irradiado, no qual os animais receberam a solução de acetato de alfa-tocoferol (vitamina E) antes de serem irradiados com dose única de 15 Gy de radiação gama na mesma região. Oito horas e trinta dias após a irradiação, os animais foram anestesiados e as glândulas parótidas dos lados direito e esquerdo foram removidas cirurgicamente. Após a excisão cirúrgica, os animais foram sacrificados por aprofundamento anestésico. As peças foram preparadas, incluídas em historesina e cortes semiseriados foram obtidos de acordo com o protocolo estabelecido pela disciplina de Histologia da Faculdade de Odontologia de Piracicaba - UNICAMP. A partir de cada bloco foram obtidas três lâminas histológicas, contendo quatro cortes alternados, com intervalo de 30 cortes entre eles. Os cortes foram montados em lâminas, corados com hematoxilina e eosina, sendo posteriormente utilizados para avaliação morfométrica. Os dados foram submetidos à análise de variância (ANOVA) e ao teste de Tukey. A análise morfométrica dos ácinos no tempo de 8 horas mostrou diferença estatisticamente significante somente entre os grupos Óleo Irradiado e Vitamina E Irradiado. No tempo de 30 dias, o grupo Vitamina E Irradiado e o grupo Irradiado, apresentaram redução significativa na quantidade de ácinos em relação ao grupo Óleo. Quando os grupos foram avaliados em função do tempo, observou-se redução significativa nos grupos Óleo Irradiado e Irradiado aos 30 dias. As análises morfométricas dos ductos intercalares e estriados não mostraram diferenças estatísticas significativas entre os grupos em ambos os tempos estudados. Dentro das condições experimentais utilizadas, conclui-se que a vitamina E demonstrou leve ação radioprotetora em glândulas parótidas irradiadas. / Abstract: The aim of this study was to evaluate, by morphometric analysis, the radioprotective effect of vitamin E in parotid glands of rats. For this purpose, ninety male rats (Rattus norvegicus, albinus, Wistar) were used, which were randomly divided into five experimental groups: Oil, corresponding to the animals that received olive oil; Irradiate Oil, a group in which the animals received olive oil and were irradiated with a single dose of 15 Gy of gamma radiation in the head and neck region; Irradiate, in which the animals were irradiated with 15 Gy single dose of gamma radiation; Vitamin E, a group in which the animals received solution of alpha-tocopherol acetate (vitamin E) but were not irradiated and Vitamin E irradiated, in which the animals received the solution of alpha-tocopherol acetate (vitamin E) before being irradiated with 15 Gy single dose of gamma radiation in the same region. Eight hours and thirty days after irradiation, the animals were anesthetized and the parotid glands of right and left sides were removed surgically. After surgical excision, the animals were sacrificed by anesthetic depth. The specimens were prepared, including in historesin and semi-series cuts were obtained in accordance with the protocol established by the discipline of Histology, Faculty of Dentistry of Piracicaba - UNICAMP. From each block were obtained three histologic slides, alternating with four cuts, with an interval of 30 cuts between them. The sections were mounted on slides, colored with hematoxylin and eosin, and then used for morphometric assessment. The data were submitted to analysis of variance (ANOVA) and Tukey test. Morphometric analysis of acinus in time of 8 hours showed statistically significant difference between the groups Vitamin E Irradiate and Oil Irradiate. At time of 30 days, the vitamin E Irradiate group and the Irradiate group, showed significant reduction in the amount of acinus compared to the Oil group. When the groups were evaluated in terms of time, there was significant reduction in the groups Oil Irradiate and Irradiate to 30 days. The morphometric analysis of interim and striated ducts showed no statistically significant differences between groups in both periods studied. Within the experimental conditions used, it is concluded that vitamin E showed mild radioprotective action in parotid glands of rats irradiated. / Mestrado / Radiologia Odontologica / Mestre em Radiologia Odontológica
5

Avaliação do efeito radioprotetor da Vitamina E na taxa de erupção dentária em ratos irradiados / Evaluation of radioprotective effect of vitamin e on rate of tooth eruption in irradiated rats

Araujo, Amanda Maria Medeiros de, 1984- 22 August 2018 (has links)
Orientador: Pedro Duarte Novaes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-22T13:44:54Z (GMT). No. of bitstreams: 1 Araujo_AmandaMariaMedeirosde_D.pdf: 1889367 bytes, checksum: 2887b6c6871cd7a7f04a05b76a8e7a1b (MD5) Previous issue date: 2013 / Resumo: O objetivo neste trabalho foi avaliar, por meio de análise histológica e taxa de erupção dentária, o efeito radioprotetor da vitamina E na região odontogênica de incisivos de ratos. Foram utilizados 40 ratos machos (Rattus norvegicus, Albinus Wistar), os quais foram divididos aleatoriamente em quatro grupos: controle (C), radioterapia (R), radioterapia + óleo de oliva (RO) e radioterapia + óleo de oliva + vitamina E (ROV), nos quais os animais dos grupos experimentais receberam doses únicas de 15 Gy de radioterapia por raios X na região de cabeça e pescoço. A taxa de erupção dentária foi medida em todos os animais durante 14 dias e os resultados avaliados estatisticamente utilizando o procedimento PROC MIXED (p?0,05). Os ratos submetidos à radioterapia apresentaram queimaduras, alopécia e perda de peso no dia do sacrifício. Constatou-se diminuição da taxa de erupção dentária dos grupos experimentais R e RO a partir do sexto dia após a radioterapia em relação ao grupo controle. A partir do décimo dia após a radioterapia ocorreu diminuição na taxa de erupção dentária de todos os ratos experimentais em relação ao controle. No início da região odontogênica dos grupos que foram submetidos à radiação, observou-se uma aparente redução na população celular da região do folículo adjacente à face lingual do órgão dentário, quando comparado ao grupo controle e alterações na formação da alça epitelial independente do tratamento aplicado. Na região odontogênica correspondente à face distal do terceiro molar, foi possível identificar intensa destruição com visível redução no tamanho do órgão dentário provocada pela falta de produção de esmalte e dentina, presença de um grande vaso e hemorragia. Dentro das condições experimentais utilizadas, concluiu se que, apesar de histologicamente não haver evidência de proteção, a vitamina E demonstrou leve ação radioprotetora na taxa de erupção dentária em ratos / Abstract: The objective of this study was to evaluate, by means of histology and rate of tooth eruption, the radioprotective effect of vitamin E in odontogenic region of rat incisors. A total of 40 male rats (Rattus norvegicus, Albinus Wistar), which were randomly divided into four groups: control (C), radiotherapy (R), radiation + olive oil (RO) and radiotherapy + olive oil + vitamin E (ROV), in which the animals of the experimental groups received single doses of 15 Gy of X-ray radiation in the head and neck. The rate of tooth eruption was measured in all animals for 14 days and the results statistically analyzed using PROC MIXED (p? 0.05). Rats treated with radiotherapy had burns, alopecia and weight loss on the day of sacrifice. Observed a decrease in the rate of tooth eruption of the experimental groups R and RO from the sixth day after radiotherapy compared to the control group. From the tenth day after radiotherapy occurred decrease in the rate of tooth eruption of all experimental rats compared to control. In the beginning of odontogenic region in the groups that underwent radiation, there was an apparent reduction in the cell population of the region adjacent to the follicle lingual dental organ when compared to the control group and changes in the formation of epithelial handle regardless of the treatment applied these. In odontogenic region corresponding to the distal face of the third molar, was identified with intense destruction visible reduction in organ size caused by lack of dental enamel and dentin production, presence of a large vessel and bleeding. Within the experimental conditions used, it was concluded that histologically there was no evidence protection, vitamin E showed mild radioprotective effect on the rate of tooth eruption in rats / Doutorado / Radiologia Odontologica / Doutora em Radiologia Odontológica
6

Effects of radiation exposure on dormant mycobacteria in vitro

Malatsi, Netty Octavia 25 August 2008 (has links)
The burgeoning tuberculosis epidemic worldwide is mainly due to the reactivation of old latent tuberculosis infection. South Africa is rated as one of the countries with the worst tuberculosis epidemic and the population that is mostly affected is the mineworkers. Reports suggest that reactivation of latent tuberculosis infection is responsible for these high tuberculosis rates in this population. Various risk factors for reactivation of latent TB have been identified and include silicosis, diabetes mellitus, immunosuppressive drug therapy, Human Immunodeficiency Virus infection and malnutrition. The aim of this study was to determine whether there is any relationship between exposure to low levels of ionizing radiation and reactivation tuberculosis by evaluating the effects of radiation on dormant mycobacteria in vitro. The Wayne in vitro dormancy model was used to induce dormancy in Mycobacterium smegmatis and Mycobacterium bovis BCG. Dormant pGFM-11- transformed and non-transformed cultures were then exposed to 0.1, 1 and 5Gray Cobalt-60 radiation. The radiation effects were evaluated using viable counts, the bacillary adenosine triphosphate assay and quantification of the green fluorescent protein expression using flow cytometry after 24 and 72 hours of radiation exposure. Exponential phase cultures treated in exactly the same way as the dormant cultures together with the cultures that were not exposed to any radiation served as controls. Dormancy was successfully induced as determined by the sensitivity of the dormant cultures to metronidazole, resistance to isoniazid and assumption of synchronous replication on dilution into oxygen-rich medium. Subsequent to exposure to Cobalt-60 radiation, the dormant cultures were sensitive to metronidazole and resistant to isoniazid and the inverse was observed in irradiated exponential phase cultures. The results suggested that both dormant and exponential phase cultures of the tested mycobacteria retained their antibiotic susceptibility pattern and thus were not affected by Cobalt-60 radiation. It was concluded that the doses of Cobalt-60 radiation used in this study did not cause the reactivation of in vitro dormant mycobacterial strains tested. / Dr. H. Abrahamse Mrs. J.V. Hind
7

Radiological dose assessment for the leaking coil replacement on the Necsa radioactive effluent evaporator facility

Kros, Charles 02 July 2014 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2013. / In this study a dose assessment is used to demonstrate conformance to national and international dose limits for workers and meets the Necsa ALARA goals for a radiological repair task. The dose assessment methodology is based on international standards, principles and criteria and involves the process of determining radiological dose, through the use of exposure scenarios, bioassay results, monitoring data, source term information, and pathway analysis. The radiological task is the replacement of the leaking steam coil on the radioactive effluent evaporator facility at Necsa. The effluent treatment facility, its operation, the origin of the radioactive effluent and hazards associated with the leaking coil are discussed. The dose assessment is supported by measurement of actual radiological conditions in the area where the task will be performed using suitable and calibrated instrumentation. The assumptions were limited to the physical phenomena associated with the behaviour of materials and available from national and international studies. The importance of proper planning of all the tasks associated with the replacement task as well as sources of inaccuracy and uncertainty associated with the calculated doses are discussed. The results of the assessment are evaluated in terms of ALARA, namely the safety fundamental principles of justification, optimisation and limitation of facilities and activities. Other dose reduction options, such as personal protective clothing and equipment, were considered to show that the doses conform to the ALARA objectives of Necsa and other operation optimisation measures.
8

In-phantom measurement of HE or neutron protection dosimetry

Jalandoni, D. Jay Moreno 12 1900 (has links)
No description available.
9

Development and use of an adoptive transfer method for detecting radiation-induced bystander effects in vivo

Blyth, Benjamin John, Unknown Date (has links)
Thesis (Ph.D.)--Flinders University, School of Medicine, Dept. of Haematology and Genetic Pathology. / Typescript bound. Includes bibliographical references: (leaves 248-282) Also available in an electronic version.
10

The influence of oxygen and dose rate on the survival of cultured mammalian cells exposed to ionizing radiation

Bedford, Joel S. January 1966 (has links)
No description available.

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