The selection of an appropriate range of doses is critical in drug self-administration, since the number of self-administrations and dose levels of a drug is interrelated, forming an inverted U-shape. The purpose of this study was to investigate the relationship between the dose to produce the reinforcing effect and that of gross behavioral effects, in order to determine dose ranges of a drug t...

A mathematical model is described that predicts the response of psoriasis to a treatment course of UVB irradiation. The basis of the model is that UVB acts by a direct effect on keratinocytes and that cell cycle arrest is the major mode of action in the phototherapeutic response in psoriasis. Although it is unlikely that UVB causes resolution of psoriatic plaques through a single mechanism, the...

Solar radiation is one of the most common threats to the skin, with exposure eliciting a specific protective cellular response. To decrypt the underlying mechanism, we used whole genome microarrays (Agilent 44K) to study epidermis gene expression in vivo in skin exposed to simulated solar radiation (SSR). We procured epidermis samples from healthy Caucasian patients, with phototypes II or III, ...

Introduction: Skin dose and depth dose distribution of some beta sources that can contaminate skin or protective clothing covering the skin have been calculated using VARSKIN2. Materials and Methods: In this research, absorbed dose to skin and depth dose from the skin surface have been calculated for 90Sr/90Y, 147Pm, 32P beta emitter radioisotopes by using input parameters: activity of source, ...

Background: The exposure of human being to ionize radiation from natural sources is a continuing, inescapable feature of life on earth. Direct measurement of absorbed dose rates in air has been carried out in many countries of the world during the last few decades. Such investigations can be useful for assessment of public dose rates, the performance of epidemiological studies, and kee...