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Researchers have taken a number of different approaches in their exploration of hippocampal function. One approach seeks to describe hippocampal function by probing the memory representations that the hippocampus supports. Another approach focuses on the role of the hippocampus in pattern separation and completion. Each of these approaches to understanding hippocampal function utilizes a distinct set of specialized tasks, and both of these task sets are known to be sensitive to changes in hippocampal function with age and disease status. But the question remains whether the tasks utilized in these two approaches tap into the same aspects of hippocampal function. We explored this question in the context of hippocampal development. Preadolescent children (N = 73) and young adults (N = 41) completed an identical battery of cognitive tasks consisting of a spatial reconstruction relational memory task, the mnemonic similarity task (MST)—an object‐based pattern separation task, and a novel hybrid task—the Object Discrimination and Distribution (ODD) Task—designed to integrate and simultaneously tax pattern separation and spatial relational memory. Children did not demonstrate impairments in lure discrimination relative to young adults on either the object‐based pattern separation task or for aspects of the ODD task that required pattern separation in the absence of relational memory demands but performed more poorly across aspects of tasks that required relational binding.  相似文献   
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Objective: The purpose was to describe the prevalence and characteristics of healthcare utilization among individuals with spinal cord injury (SCI) from a Level I trauma center.

Design: Retrospective data analysis utilizing a local acute trauma registry for initial hospitalization and merged with the Dallas-Fort Worth Hospital Council registry to obtain subsequent health care utilization in the first post-injury year.

Setting: Dallas, TX, USA.

Participants: Six hundred and sixty four patients were admitted with an acute traumatic SCI from January 2003 through June 2014 to a Level I trauma center. Fifty five patients that expired during initial hospitalization and 18 patients with unspecified SCI (defined by ICD-9 with no etiology or level of injury specified) were not included in the analysis, leaving a final sample of 591.

Outcome Measures: Data included demographic and clinical characteristics, charges, and healthcare utilization.

Results: Mean age was 46.1?years (±18.9?years), the majority of patients were male (74%), and Caucasian (58%). Of the 591 patients, 345 (58%) had additional inpatient or emergency healthcare utilization accounting for 769 additional visits (median of 3 visits per person). Of the 769 encounters, 534 (69%) were inpatient and 235 (31%) were emergency visits not resulting in an admission. The most prevalent ICD-9 codes listed were pressure ulcer, neurogenic bowel, neurogenic bladder, urinary tract infection, fluid electrolyte imbalance, hypertension, and tobacco use.

Conclusion: Individuals with SCI experience high levels of healthcare utilization which are costly and may be preventable. Increasing our understanding of the prevalence and causes for healthcare utilization after acute SCI is important to target preventive strategies.  相似文献   

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Prosthetic valve infective endocarditis (IE) is one of the most serious postimplantation complications. Prosthetic aortic valve IE constitutes 1%–6% of all prosthetic valve IE cases. We present a dramatic echocardiographic case of prosthetic aortic valve IE leading to near‐complete valve dehiscence. Echocardiographic evidence of prosthetic aortic valve rocking motion is indicative of significant dehiscence. Aside from IE, other causes and risk factors for prosthetic aortic valve dehiscence include inflammatory and autoimmune vasculitides, concomitant ascending aorta aneurysm, and aortic root calcification.  相似文献   
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