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101.
Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited.  相似文献   
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ObjectiveTo evaluate changes in insurance status among emergency department (ED) patients presenting in the two years immediately before and after full implementation of the Affordable Care Act (ACA).MethodsWe evaluated National Hospital Ambulatory Medical Care Survey (NHAMCS) Emergency Department public use data for 2012–2015, categorizing patients as having any insurance (private; Medicare; Medicaid; workers' compensation) or no insurance. We compared the pre- and post-ACA frequency of insurance coverage—overall and within the older (≥65), working-age (18–64) and pediatric (<18) subpopulations—using unadjusted odds ratios with 95% confidence intervals. We also conducted a difference-in-differences analysis comparing the change in insurance coverage among working-age patients with that observed for older Medicare-eligible patients, while controlling for sex, race and underlying temporal trends.ResultsOverall, the proportion of ED patients with any insurance did not significantly change from 2012 to 2013 to 2014–2015 (74.2% vs 77.7%) but the proportion of working-age adult patients with at least one form of insurance increased significantly, from 66.0% to 71.8% (OR 1.31, CI: 1.13–1.52). The difference-in-differences analysis confirmed the change in insurance coverage among working-age adults was greater than that seen in the reference population of Medicare-eligible adults (AOR 1.70, CI: 1.29–2.23). The increase was almost entirely attributable to increased Medicaid coverage.ConclusionIn the first two years following full implementation of the ACA, there was a significant increase in the proportion of working-age adult ED patients who had at least one form of health insurance. The increase appeared primarily associated with expansion of Medicaid.  相似文献   
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Background

Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.

Methods

A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.

Results

Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.

Conclusion

Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile.  相似文献   
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Background

Observational studies of the relative effectiveness of influenza vaccines are essential for public health decision making. Their estimates, however, are subject to bias due to unmeasured confounders. Instrumental variable (IV) methods can control for observed and unobserved confounders.

Methods

We used linked electronic medical record databases in the Veterans Health Administration (VHA) as well as Medicare administrative files to examine the relative vaccine effectiveness (rVE) of high-dose influenza vaccine (HD) versus standard-dose influenza vaccines (SD) in preventing hospitalizations among VHA-enrolled Veterans ≥65?years of age during 5 influenza seasons (2010–2011 through 2014–2015). Using multivariable IV Poisson regression modeling to address unmeasured confounding and bias, we analyzed the data by each season and through longitudinal analysis of all five seasons.

Findings

We included 3,638,924 person–influenza seasons of observation where 158,636 (4%) were among HD vaccine recipients and 3,480,288 (96%) were among SD vaccine recipients. Of the 1,728,562 Veterans, 1,702,824 (98.5%) were male and 1,299,412 (75%) were non-Hispanic white. Based on the longitudinal analysis of all five seasons, the IV-adjusted rVE estimate of HD vs. SD was 10% (95% CI, 8–12%) against all-cause hospitalization; 18% (95% CI, 15–21%) against cardiorespiratory-associated hospitalization; and 14% (95% CI, 6–22%) against influenza/pneumonia-associated hospitalization. The findings by season were similar.

Interpretation

Our analysis of VHA clinical data collected from approximately 1.7 million Veterans 65?years and older during five seasons demonstrates that high-dose influenza vaccine is more effective than standard-dose influenza vaccines in preventing influenza- or pneumonia-associated hospitalizations, cardiorespiratory hospitalizations, and all-cause hospitalizations.  相似文献   
108.
Choledochal cysts (CDCs) and biliary atresia (BA) are rare pediatric hepatobiliary anomalies that require surgical intervention due to increased risk of malignancy and liver failure, respectively. The underlying disease and operative procedures place patients at risk for long‐term complications, which may continue to affect them into adulthood. Lack of a transitional care model in the health‐care system potentiates the challenges they will face following aging out of their pediatric providers' care. We sought to elucidate the long‐term complications and challenges patients with CDCs and BA face, review the current literature regarding transitioning care, and propose guidelines aiding adult providers in continued care and surveillance of these patients. A literature review was performed to assess short‐term and long‐term complications after surgery and the current standards for transitioning care in patients with a history of CDCs and BA. While transitional programs exist for patients with other gastrointestinal diseases, there are few that focus on CDCs or BA. Generally, authors encourage medical record transmission from pediatric to adult providers, ensuring accuracy of information and compliance with treatment plans. Patients with CDCs are at risk for developing biliary malignancies, cholangitis, and anastomotic strictures after resection. Patients with BA develop progressive liver failure, necessitating transplantation. There are no consensus guidelines regarding timing of follow up for these patients. Based on the best available evidence, we propose a schema for long‐term surveillance.  相似文献   
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