The dose-response relationship of ionizing radiation and its stochastic effects has been thought to be linear without any thresholds. The basic data for this model were obtained from mutational assays in the male germ cells of the fruit fly Drosophila melanogaster. However, it is more appropriate to examine carcinogenic activity in somatic cells than in germ cells. Here the dose-response relati...

background: the electrical dose selected for electroconvulsive therapy (ect) must have an acceptable efficacy and no or minimal cognitive side-effects. we evaluated the clinical efficacy and cognitive side-effects of ect in relation to the stimulus dose administered.   method: this study assessed 71 depressed patients who were treated with bilateral ect. for evaluation of depressive and cogniti...

BACKGROUND There is considerable evidence of the favourable role of more physical activity (PA) in fighting against dementia. However, the shape of the dose-response relationship is still unclear. OBJECTIVE To quantitatively investigate the relationship between dementia and PA. DESIGN PubMed, EMBASE, Ovid and the Cochrane Library were searched for prospective studies published from 1 Januar...

BACKGROUND Our aim was to identify a dose-volume response relationship for brain metastases treated with frameless stereotactic radiosurgery (SRS). METHODS We reviewed patients who underwent frameless single-fraction linear accelerator SRS for brain metastases between 2007 and 2013 from an institutional database. Proportional hazards modeling was used to identify predictors of outcome. A rati...

The term hormesis describes a dose-response relationship that is characterized by a response that is opposite above and below the toxicological or pharmacological threshold. Previous reports have shown that this relationship is ubiquitous in the response of pharmaceuticals, metals, organic chemicals, radiation, and physical stressor agents. Recent reports have also indicated that certain nanopa...