Sökning: "radiation dose"
Visar resultat 1 - 5 av 361 avhandlingar innehållade orden radiation dose.
1. Dose painting : Can radiotherapy be improved with image driven dose-responses derived from retrospective radiotherapy data?
Sammanfattning : The main aim of curative radiotherapy for cancer is to prescribe and deliver doses that eradicate the tumor and spare the normal healthy tissues. Radiotherapy is commonly performed by delivering a homogeneous radiation dose to the tumor. 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
3. 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
Sammanfattning : Computed tomography urography (CTU) is today the imaging method used to investigate patients with suspected urinary tract malignancy, replacing the old imaging method intravenous pyelography (IVP) about a decade ago. The downside of this shift was that the effective radiation dose to the examined patient was eight times higher for CTU compared to IVP. LÄS MER
5. Short and long-term effects of exposure to low dose and low dose rate of gamma radiation : using in vitro and in vivo models
Sammanfattning : Assessment of human health risks from exposure to ionizing radiation (IR) is mainly based on the extrapolation of results from epidemiological studies on populations exposed to relatively high doses and often at high dose rates (HDR). Risk estimates after exposure to low doses and in particular at low dose rates (LDR) remain controversial due to a lack of epidemiological evidence. LÄS MER