Sökning: "radiation dose"

Visar resultat 11 - 15 av 401 avhandlingar innehållade orden radiation dose.

1. 11. Accurate description of heterogeneous tumors for biologically optimized radiation therapy

   Författare :Johan Nilsson; Bengt Lind; Anders Brahme; Margareta Edgren; Søren Bentzen; Stockholms universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; heterogeneous tumors; radiation therapy; biological optimization; tumor hypoxia; effective radiation sensitivity; effective radiation resistance; Radiation biology; Strålningsbiologi;

   Sammanfattning : In this thesis, a model of tissue oxygenation is presented, that takes into account the heterogeneous nature of tumor vasculature. Even though the model is rather simple, the resulting oxygen distributions agree very well with clinically observed oxygen distributions for most tumors and healthy normal tissues. LÄS MER

3. 12. Radiation induced biomarkers of individual sensitivity to radiation therapy

   Författare :Sara Skiöld; Mats Harms-Ringdahl; Siamak Haghdoost; Mats Ljungman; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; low dose ionizing radiation; radiation sensitivity; proteomics; whole blood; 8-oxo-dG; oxidative stress; acute adverse healthy tissue effects; molekylär biovetenskap; Molecular Bioscience;

   Sammanfattning : Fifty percent of solid cancers are treated with radiation therapy (RT). The dose used in RT is adjusted to the most sensitive individuals so that not more than 5% of the patients will have severe adverse healthy tissue effects. LÄS MER

4. 13. Ethical aspects of radiation protection

   Författare :Per Wikman-Svahn; John Cantwell; Gustaf Arrhenius; KTH; []
   Nyckelord :HUMANIORA; HUMANITIES; Radiation; risk; ethics; Philosophy subjects; Filosofiämnen;

   Sammanfattning : This aim of this thesis is to examine ethical aspects of radiation protection from ionizing radiation. Radiation protection is the professional field that deals with the protection of humans and the environment from the harmful effects of radiation. LÄS MER

5. 14. Role of MTH1 and MYH proteins in genotoxic effects of radiation

   Författare :Sara Shakeri Manesh; Siamak Haghdoost; William F. Morgan; Stockholms universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MTH1; MYH; gamma radiation; UV radiation; oxidative stress; low dose rate ionizing radiation; molekylärgenetik; Molecular Genetics;

   Sammanfattning : Humans are constantly exposed to different types of radiations. It has been suggested that low dose and low dose rate of γ-radiation as well as ultra violet A (UVA) induce oxidative stress in cells that may promote mutations. LÄS MER

7. 15. Development and evaluation of an independent system for absorbed dose calculations in radiotherapy

   Författare :Stefan Johnsson; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; medicinsk instrumentering; tomografi; radiologi; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; cancer; Cytologi; onkologi; cancerology; oncology; Cytology; PDA; mini-phantom; in-air equivalence; primary kerma; transmission measurement; stopping power ratio; entrance dose; beam quality; quality control; error prevention; monitor unit calculation; radiation therapy; dose calculation;

   Sammanfattning : The aim of this work was to develop, implement and evaluate an independent system with which to calculate the absorbed dose, delivered by high-energy X-ray beams, to the prescription point and the depth of dose maximum. The introduction of such a system in the clinical routine may help ensure high-quality treatment and avoidance of errors which may jeopardise the clinical outcome of the treatment (i. LÄS MER