Sökning: "High dose rate"

Visar resultat 1 - 5 av 257 avhandlingar innehållade orden High dose rate.

1. 1. Biomarkers of ionising radiation relevant to carcinogenesis : Dose, dose rate and LET dependency of the responses

   Författare :Milagrosa López Riego; Andrzej Wojcik; Lovisa Lundholm; Alexandros G. Georgakilas; Stockholms universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Ionising radiation; low dose; low dose rate; linear energy transfer LET ; mixed beams; dose and dose rate effectiveness factor DDREF ; cancer; DNA damage response; biomarkers; molekylär biovetenskap; Molecular Bioscience;

   Sammanfattning : A better understanding of the relationship between ionising radiation (IR) dose, dose rate and radiation quality, and the risk of stochastic effects would improve risk extrapolation from atomic bomb survivors’ data. Owing to insufficient statistical power of epidemiological studies to detect excess incidence of cancer following low doses of IR delivered at low dose rates (LDLDR), as typically encountered in most common human exposure scenarios, radiobiological experiments are fundamental to describe the biological effectiveness of LDLDR and to define the underlying molecular mechanisms. LÄS MER

3. 2. Short and long-term effects of exposure to low dose and low dose rate of gamma radiation : using in vitro and in vivo models

   Författare :Traimate Sangsuwan; Siamak Haghdoost; Eva Forssell-Aronsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Low dose; Low dose rate; High dose rate; Ionizing radiation; Adaptive response; Senescence; Premature senescence; Oxidative stress; Drosophila embryo; Mutation; DNA repair; molekylär biovetenskap; Molecular Bioscience;

   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

4. 3. Dose Escalation with High Dose Rate Brachytherapy or Protons in Curative Radiotherapy of Prostate Cancer

   Författare :Lennart Åström; Lars Holmberg; Gunilla Enblad; Henrik Grönberg; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Prostate cancer; radiotherapy; brachytherapy; high dose rate; protons; PSA bounce;

   Sammanfattning : The aim of the thesis was to study the outcome and side effects after dose-escalated radiotherapy with high dose rate brachytherapy (HDR-BT) or proton beam therapy (PBT) boost in prostate cancer.The first cohorts of men in Sweden treated with either HDR-BT or PBT in combination with conventional photon beam therapy (2 Gray (Gy) fractions to 50 Gy) were analysed. LÄS MER

5. 4. Biological effects of high energy radiation and ultra high dose rates

   Författare :Björn Zackrisson; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiobiology; 50 MV x-rays; 50 MeV electrons; in vitro; in vivo; RBE; OER; ultra high dose-rate; radiobiological models; model selection; models of stochastic processes;

   Sammanfattning : Recently a powerful electron accelerator, 50 MeV race-track microtron, has been taken into clinical use. This gives the opportunity to treat patients with higher x-ray and electron energies than before. Furthermore, treatments can be performed were the entire fractional dose can be delivered in parts of a second. LÄS MER

7. 5. Cellular effects of ionizing radiation : Relevant for understanding cancer risk after medical and environmental radiation exposures

   Författare :Pamela Chiaka Akuwudike; Andrzej Wojcik; Lovisa Lundholm; Kerstin Borgmann; Stockholms universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiation; DNA damage; radiation-induced carcinogenesis; second primary cancer; cisplatin chemoradiotherapy; dose fractionation; low dose; low dose rate; dose and dose rate effectiveness factor DDREF ; molekylär biovetenskap; Molecular Bioscience;

   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