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Recently, a phenomenon known as sexting, defined here as the transfer of sexually explicit photos via cell phone, has received substantial attention in the U.S. national media. To determine the current and potential future impact of sexting, more information about the behavior and the attitudes and beliefs surrounding it must be gathered, particularly as it relates to sexting by minors. The present study was designed to provide preliminary information about this phenomenon. Participants were 606 high school students (representing 98 % of the available student body) recruited from a single private high school in the southwestern U.S. Nearly 20 % of all participants reported they had ever sent a sexually explicit image of themselves via cell phone while almost twice as many reported that they had ever received a sexually explicit picture via cell phone and, of these, over 25 % indicated that they had forwarded such a picture to others. Of those reporting having sent a sexually explicit cell phone picture, over a third did so despite believing that there could be serious legal and other consequences attached to the behavior. Given the potential legal and psychological risks associated with sexting, it is important for adolescents, parents, school administrators, and even legislators and law enforcement to understand this behavior.  相似文献   
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The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D) were found to be elevated. In the fornix, K was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D were elevated, as were FA, MD, and D in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice.  相似文献   
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Introduction  Patients undergoing major hepatectomy are at increased risk for post-operative morbidity and mortality, and changes in the phenotype of effector cells may predispose these patients to infectious sequelae. Methods  To better understand post-hepatectomy immune responses, peripheral blood from 15 hepatectomy patients was drawn immediately before and after liver resection and on post-operative days 1, 3, and 5. Circulating monocytes and dendritic cells were analyzed by flow cytometry for quantity, phenotype, activation status, human leukocyte antigen DR (HLA-DR) expression, and toll-like receptor-2 and -4 expression. Results  Major hepatectomy increased the numbers of activated CD16bright blood monocytes and the percentage of activated dendritic cells, although monocyte HLA-DR expression was reduced. These results may represent both dysfunctional antigen presentation and pending anergy, as well as cellular priming of immune effector cells. Better understanding of the alterations in innate immunity induced by hepatectomy may identify strategies to reduce infectious outcomes.  相似文献   
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Context

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of cancer treatment and may adversely affect quality of life (QOL) for years.

Objectives

We explored the long-term effects of electroencephalographic neurofeedback (NFB) as a treatment for CIPN and other aspects of QOL.

Methods

Seventy-one cancer survivors (mean age 62.5; 87% females) with CIPN were randomized to NFB or to a waitlist control (WLC) group. The NFB group underwent 20 sessions of NFB where rewards were given for voluntary changes in electroencephalography. Measurements of pain, cancer-related symptoms, QOL, sleep, and fatigue were obtained at baseline, end of treatment, and one and four months later.

Results

Seventy one participants enrolled in the study. At the end of treatment, 30 in the NFB group and 32 in the WLC group completed assessments; at four months, 23 in the NFB group and 28 in the WLC completed assessments. Linear mixed model analysis revealed significant group × time interaction for pain severity. A general linear model determined that the NFB group had greater improvements in worst pain (primary outcome) and other symptoms such as numbness, cancer-related symptom severity, symptom interference, physical functioning, general health, and fatigue compared with the WLC group at the end of treatment and four months (all P < 0.05). Effect sizes were moderate or large for most measures.

Conclusion

NFB appears to result in long-term reduction in multiple CIPN symptoms and improved postchemotherapy QOL and fatigue.  相似文献   
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AIMS: Atherosclerosis can be viewed as a low grade inflammatory process, and genetic polymorphisms within cytokines are candidate risk factors for the development of atherosclerosis. We examined the association of a common functional variant in the IL-6 gene with carotid intimal-medial wall thickness (IMT) and the presence of plaques in a randomly selected, cross-sectional Australian population. METHODS: B-mode carotid ultrasound was performed on 1109 subjects aged 27-77 years, who were genotyped for the IL-6 polymorphism (-174G>C) and assessed for conventional cardiovascular risk factors. RESULTS: The frequency of the IL-6 -174C allele was 0.41. Initial univariate analysis showed no association of the IL-6 -174G>C polymorphism with carotid IMT. Multivariate analysis however showed an association of the IL-6 -174C allele with increased IMT in subjects older than the median age of 53 years (P=0.005). Initial univariate analysis of the IL-6 -174G>C polymorphism and carotid plaque showed no association in the whole sample. In multivariate analysis the -174C allele was independently associated with an increased risk of carotid plaque in the whole sample (CC vs GG, OR=2.22, 95% CI=1.32 to 3.73, P=0.003). CONCLUSIONS: This study shows that the IL-6 -174G>C variant is independently associated with carotid plaque formation in the whole population and an increased carotid IMT in older subjects within a randomly selected, cross-sectional Australian population.  相似文献   
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