Suncus murinus/Dose-survival time response/Weight loss The overall survival time response of Suncus murinus, one of the insectivora, under whole body x-irradiation in the dose range of 500 to 50,000 rad was investigated. Three segments of bone marrow, gastrointestinal (GI), and central nervous system (CNS) deaths in the dose survival time response curve were similar to those of other species su...

• Limit dose test – this is the preferred test when toxicity is expected to be low and lethality is unlikely at the limit dose. The limit dose must be adequate for assessment purposes, and it is usually 2000 mg/kg body-weight. • Full test: LD50-only test – this is the preferred test when an estimate of the median lethal dose is required but neither the slope of the dose response curve or the co...

The interaction of gastrin and secretin, in the regulation of human lower esophageal sphincter competence, was studied in 54 normal subjects. A dose-response curve, for the lower esophageal sphincter, was constructed from the rapid intravenous injections of synthetic gastrin I (amino acid sequence 2-17). This curve was sigmoid shaped and showed a peak response that was 460.0 +/-24.0% (mean +/-2...

Recent technological advances enable radiation therapy to be delivered in a highly conformal manner to targets located almost anywhere in the body. This capability has renewed the clinical interest in hypofractionation wherein the tumor is delivered a few fractions of very large dose per fraction. Extrapolating clinical experience from conventional regimens to fractions of high dose is importan...

beryllium  oxide  (beo)  nanopowder  was  synthesized  using  sol-gel method  and  the  effects  of  changes of  chemical  reagents  were investigated.  because  of  tissue  equivalence  and  other  outstanding thermoluminescence  (tl) properties of  the bulk material  in x and γ dosimetry, the applicability of this nanostructure in tl dosimetry was studied  following  irradiation to  the 137 c...

Dose-response data for GH-releasing peptides are limited. We studied the effects of varying doses (0-1.0 microgram/kg) of hexarelin, a novel GH-releasing peptide, administered iv to healthy adult males on GH, PRL, and cortisol release. In addition, we studied the effect of administration of a single dose of GHRH-(1-29)-NH2 (1.0 microgram/kg), alone or in combination with a low dose of hexarelin...

Beta adrenergic agents given by aerosol decrease the responsiveness of the airways to histamine and methacholine in subjects with asthma, causing a shift of the dose response curve to the right. To find out whether the shift is related to the dose of beta adrenergic agent given and to determine the duration of the reduced responsiveness, eight subjects with asthma were given histamine inhalatio...

Some Areas of Ramsar, a city in northern Iran are among the world’s wellknown inhabited areas with highest levels of natural radiation. Annual exposure levels in these areas are up to 260 mGy y‐1 and the mean exposure rate is about 10 mGy y‐1 for a population of about 2000 residents. If elevated levels of natural radiation as high as a few hundred mSv per year is detrimental to health and...

Dose-response relationships for incidence are based on quantal response measures. A defined effect is either present or not present in an individual. The dose-incidence curve therefore reflects differences in individual susceptibility (the "tolerance distribution"). At low dose, only the more susceptible individuals manifest the effect, while higher doses are required for more resistant individ...