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PURPOSESexual activity is an important component of quality of life for women across their lifespan. Prior studies show a decline in sexual activity with age, but these studies often fail to consider the role of sexual satisfaction. The aim of this study is to give updated prevalence estimates of sexual activity among women and to elucidate factors associated with sexual activity and sexual satisfaction.METHODSWe report a cross-sectional analysis of the second wave of a nationally representative sample of US adults aged 28 to 84 years, the Survey of Midlife Development in the United States. The survey used self-administered questionnaires to assess demographic data, self-rated physical and mental health, medical problems and medication use, relationship factors, and sexual activity and satisfaction.RESULTSOf 2,116 women who answered the questions regarding sexuality, 1,345 (61.8%) women were sexually active in the previous 6 months. The proportion of women who were sexually active decreased with advancing age. Women who were married or cohabitating had approximately 8 times higher odds of being sexually active (odds ratio = 7.91, 95% CI, 4.16–15.04; P <.001). Among women aged 60 years and older who were married or cohabitating, most (59.0%) were sexually active. Among women who were sexually active, higher relationship satisfaction (P <.001), better communication (P = .011), and higher importance of sex P = .040) were related to higher sexual satisfaction, but age was not (P = .79).CONCLUSIONSA considerable proportion of midlife and older women remain sexually active if they have a partner available. Psychosocial factors (relationship satisfaction, communication with romantic partner, and importance of sex) matter more to sexual satisfaction than aging among midlife and older women.  相似文献   
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CardioVascular and Interventional Radiology - To perform a systematic review and meta-analysis to quantify the technical success rate of adrenal venous sampling (AVS) with and without...  相似文献   
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Increased concentrations of insulin-like growth factor (IGF) system components have previously been observed in rheumatoid arthritis (RA) and osteoarthritis (OA); however, disruption of the IGF axis and the implications for the disease process remain largely unaddressed. This study was undertaken to characterise the IGF binding protein (IGFBP)-3 proteolysis and complex formation systems in synovial fluid and to investigate changes in these systems in arthritic disease, and their impact on the availability of IGF. Western blotting or autoradiography of SDS gels was used to visualise IGFBP-3 or its proteolysis. IGF-I and IGFBP-3 concentrations were determined by radioimmunoassays and acid-labile subunit (ALS) was measured by ELISA. A shift in distribution of IGFBP-3 and IGF-I in RA and OA synovial fluids (RASynF, OASynF) and an associated increase in ALS suggested the presence of 150 kDa ternary complexes. IGFBP-3 proteolysis was decreased in RASynF and OASynF, but was apparent in size-fractionated fluid and resembled serum activity. The presence of serum-like inhibitors of IGFBP-3 proteolysis in RASynF was also demonstrated by the ability of this fluid, and 150 kDa fractions from its size fractionation, to inhibit IGFBP-3 proteolysis in the other synovial fluid. A marked disruption in the IGF system was observed, as considerably more IGF-I was retained in ternary complexes. We also classified the IGFBP-3 proteolysis system in synovial fluid and found it to be disturbed in RASynF and OASynF. These changes may be caused by an increased flux of circulatory proteins into synovial fluid, resulting from an inflammation-induced increase in vascular permeability. The net result in RA and OA would be a decrease in IGF availability in arthritic joints, and therefore loss of a potential anabolic stimulus. This disruption to the IGF axis would influence disease progression in RA and OA.  相似文献   
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Introduction: Histone deacetylases (HDACs) have been implicated in neurogenic muscle atrophy, but the mechanisms by which HDAC inhibitors might have beneficial effects are not defined. Methods: We used sciatic nerve crush to determine the effect of butyrate on denervation‐induced gene expression and oxidative stress. Results: Butyrate treatment initiated 3 weeks before injury and continued 1 week after injury increases histone acetylation and reduces muscle atrophy after nerve crush. Butyrate delivered only after nerve crush similarly prevented muscle atrophy. Butyrate had no effect on the increase in histone deacetylase 4 (HDAC4) protein levels following nerve crush but prevented the increase in expression of myogenin, MuRF1, and atrogin‐1. Butyrate did not affect mitochondrial reactive oxygen species production, but it increased antioxidant enzyme activity, reduced proteasome activity, and reduced oxidative damage following nerve injury. Conclusions: These data suggest that HDAC inhibitors are promising pharmacological agents for treating neurogenic muscle atrophy. Muscle Nerve 52: 859–868, 2015  相似文献   
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The trajectory of the developing brain is characterized by a sequence of complex, nonlinear patterns that occur at systematic stages of maturation. Although significant prior neuroimaging research has shed light on these patterns, the challenge of accurately characterizing brain maturation, and identifying areas of accelerated or delayed development, remains. Altered brain development, particularly during the earliest stages of life, is believed to be associated with many neurological and neuropsychiatric disorders. In this work, we develop a framework to construct voxel‐wise estimates of brain age based on magnetic resonance imaging measures sensitive to myelin content. 198 myelin water fraction (VFM) maps were acquired from healthy male and female infants and toddlers, 3 to 48 months of age, and used to train a sigmoidal‐based maturational model. The validity of the approach was then established by testing the model on 129 different VFM datasets. Results revealed the approach to have high accuracy, with a mean absolute percent error of 13% in males and 14% in females, and high predictive ability, with correlation coefficients between estimated and true ages of 0.945 in males and 0.94 in females. This work represents a new approach toward mapping brain maturity, and may provide a more faithful staging of brain maturation in infants beyond chronological or gestation‐corrected age, allowing earlier identification of atypical regional brain development. Hum Brain Mapp 36:1233–1244, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc .  相似文献   
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