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It is now well established that estrogens can influence a panoply of physiological and behavioral functions. In many instances, the effects of estrogens are mediated by the 'classical' actions of two different estrogen receptors (ERs), ERα or ERβ. ERα and ERβ appear to have opposing actions in the control of stress responses and modulate different neurotransmitter or neuropeptide systems. Studies elucidating the molecular mechanisms for such regulatory processes are currently in progress. Furthermore, the use of ERα and ERβ knockout mouse lines has allowed the exploration of the importance of these receptors in behavioral responses such as anxiety-like and depressive-like behaviors. This review examines some of the recent advances in our knowledge of hormonal control of neuroendocrine and behavioral responses to stress and underscore the importance of these receptors as future therapeutic targets for control of stress-related signaling pathways.  相似文献   
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Background  

Increased intestinal permeability (IP) has been implicated in the etiopathogenesis, disease activity and relapse of Crohn’s disease (CD). Glutamine, the major fuel for the enterocytes, may improve IP.  相似文献   
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This study evaluated the effects of moderate to severe brain injury on cognitive task performance and cortical activation. Five participants completed a Stroop task while undergoing functional magnetic resonance imaging (fMRI) at two time points post-injury. Results revealed activation within regions typically activated during a Stroop task (the region of interest: ROI), though variability among participants was evident. Regions outside of the ROI were activated among all participants, to a greater degree than was present within the ROIs. This finding may indicate that recruitment of outside regions was necessary for successful task completion at both time points, and may suggest functional plasticity in cognitive task completion.  相似文献   
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Background

The incidence of infected urolithiasis is unknown, and evidence describing the optimal management strategy for obstruction is equivocal.

Objective

To examine the trends of infected urolithiasis in the United States, the practice patterns of competing treatment modalities, and to compare adverse outcomes.

Design, setting, and participants

A weighted estimate of 396 385 adult patients hospitalized with infected urolithiasis was extracted from the Nationwide Inpatient Sample, 1999–2009.

Outcome measurements and statistical analysis

Time trend analysis examined the incidence of infected urolithiasis and associated sepsis, as well as rates of retrograde ureteral catheterization and percutaneous nephrostomy (PCN) for urgent/emergent decompression. Propensity-score matching compared the rates of adverse outcomes between approaches.

Results and limitations

Between 1999 and 2009, the incidence of infected urolithiasis in women increased from 15.5 (95% confidence interval [CI], 15.3–15.6) to 27.6 (27.4–27.8)/100 000); men increased from 7.8 (7.7–7.9) to 12.1 (12.0–12.3)/100 000. Rates of associated sepsis increased from 6.9% to 8.5% (p = 0.013), and severe sepsis increased from 1.7% to 3.2% (p < 0.001); mortality rates remained stable at 0.25–0.20% (p = 0.150). Among those undergoing immediate decompression, 113 459 (28.6%), PCN utilization decreased from 16.1% to 11.2% (p = 0.001), with significant regional variability. In matched analysis, PCN showed higher rates of sepsis (odds ratio [OR]: 1.63; 95% CI, 1.52–1.74), severe sepsis (OR: 2.28; 95% CI, 2.06–2.52), prolonged length of stay (OR: 3.18; 95% CI, 3.01–3.34), elevated hospital charges (OR: 2.71; 95%CI, 2.57–2.85), and mortality (OR: 3.14; 95%CI, 13–4.63). However, observational data preclude the assessment of timing between outcome and intervention, and disease severity.

Conclusions

Between 1999 and 2009, women were twice as likely to have infected urolithiasis. Rates of associated sepsis and severe sepsis increased, but mortality rates remained stable. Analysis of competing treatment strategies for immediate decompression demonstrates decreasing utilization of PCN, which showed higher rates of adverse outcomes. These findings should be viewed as preliminary and hypothesis generating, demonstrating the pressing need for further study.  相似文献   
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