background: in order to improve the evaluation of possible rectal toxicity based on the rectal normal tissue complication probability (ntcp), we consider the fractional dependence of the ntcp on the wall thickness (tw) and rectal displacement (rm). materials and methods: the two-dimensional ntcp model (ntcp2d) was developed using radiotherapy plans of ten randomly selected patients with prostat...

Background: In order to improve the evaluation of possible rectal toxicity based on the rectal normal tissue complication probability (NTCP), we consider the fractional dependence of the NTCP on the wall thickness (tW) and rectal displacement (RM). Materials and Methods: The two-dimensional NTCP model (NTCP2D) was developed using radiotherapy plans of ten randomly selected patients with prostat...

The purpose of this study is to examine risk factors for late rectal toxicity for localized prostate cancer patients treated with helical tomotherapy (HT). The patient cohort of this retrospective study was composed of 241 patients treated with HT and followed up regularly. Toxicity levels were scored according to the Radiation Therapy Oncology Group grading scale. The clinical and dosimetric p...

the incidence of brain neoplasm has been progressively increasing in recent years in the industrialized countries. one of the reasons for this increased incidence could be better access to health care and improved diagnosis in the industrialized countries. it also appears that caucasians have a higher incidence than blacks or hispanics or asians. a number of risk factors have been identified an...

Temporally resolved environmental risk assessment of fluctuating concentrations of micropollutants is presented. We separated the prediction of toxicity over time from the extrapolation from one to many species and from acute to sublethal effects. A toxicokinetic-toxicodynamic (TKTD) model predicted toxicity caused by fluctuating concentrations of diazinon, measured by time-resolved sampling ov...

abstract background: the increase in breast cancer incidence has enhanced attention towards breast cancer risk. the aim of this study was to determine the risk of breast cancer and risk perception of women, factors that affect risk perception, and to determine differences between absolute risk and the perception of risk. methods: this cross-sectional study was carried out among 346 women whose ...

Background & Aims of the Study: The present research aims to use sediment quality indices in the assessment of toxicity and ecological risk factors of heavy metals Pb, Cu and Zn in Anzali, Meighan, Shadegan and Hashilan wetlands. Material & Methods: Given the environmental conditions, surface sediments in 71 diverse stations were sampled in three replications. Having preparation and subject...