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Aims: An Ecological approach to alcohol behaviour focuses on understanding individual–environment transactions, rather than on cognitive antecedents of behaviour. Meaning exists in the interdependence of individuals and their environments, in terms of affordances. Through subjective experience, this study focussed on group viewpoints related to alcohol-related affordances, or opportunities to consume alcohol in shared drinking environments. Methods: Forty students with a range of self-reported drinking behaviours participated in a Q-Methodology study, ranking 60 statements along a symmetrical grid. This varied concourse of alcohol-related affordances was obtained from a previous observation study within licenced premises and a photo-elicitation interview study with drinkers. Findings: Factor analysis and post-sort interviews revealed four subjective perspectives held by groups about their drinking behaviour: 13 participants were aware of contextual influences, but autonomous in their drinking choices; 12 participants were conscious of influences and compliant to their effects; six participants were unaware of influences, but unanimous with their peers; two participants were concerned about acting appropriately in a context by taking up canonical affordances. Conclusions: Grouping subjectivities from a varied concourse of affordances can reveal subjective experience in relation to drinking environments and alcohol behaviour. This conceptual approach for understanding drinking behaviour should be studied further.  相似文献   
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Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC50 and IC90) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.  相似文献   
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Genetically informative designs and, in particular, twin studies, are the most widely used methodology to analyse the relative contribution of genetic and environmental factors to inter-individual variability. These studies basically compare the degree of phenotypical similarity between monozygotic and dizygotic twin pairs. In addition to the traditional estimate of heritability, this kind of registry enables a wide variety of analyses which are unique due to the characteristics of the sample. The Murcia Twin Registry is population-based and focused on the analysis of health-related behaviour. The observed prevalence of health problems is comparable to that of other regional and national reference samples, which guarantees its representativeness. Overall, the characteristics of the Registry facilitate developing various types of research as well as genetically informative designs, and collaboration with different initiatives and consortia.  相似文献   
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