Visar resultat 1 - 5 av 2026 avhandlingar innehållade ordet radiation.
1. The microdosimetric variance-covariance method used for beam quality characterization in radiation protection and radiation therapy
Sammanfattning : Radiation quality is described by the RBE (relative biological effectiveness) that varies with the ionizing ability of the radiation. Microdosimetric quantities describe distributions of energy imparted to small volumes and can be related to RBE. LÄS MER
2. Cellular effects of ionizing radiation : Relevant for understanding cancer risk after medical and environmental radiation exposures
Sammanfattning : Radiation-induced cancers are stochastic and delayed effects of exposure to ionizing radiation. The dose-response relationship for radiation-induced cancers at both low dose/low dose rates and high doses (doses encountered during radiotherapy) remains unclear. LÄS MER
Sammanfattning : In recent years intensity modulated radiation therapy with photons (xIMRT) has gained attention due to its ability to reduce the dose in the tissues close to the tumour volume. However, this technique also results in a large low dose volume. LÄS MER
Sammanfattning : The primary treatment for colorectal cancer is surgery. Radiotherapy and chemotherapy, sometimes combined, are also frequently used to diminish recurrence risk. In response to radiation exposure, several cellular signaling cascades are activated to repair DNA breaks, prevent apoptosis and to keep the cells proliferating. LÄS MER
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