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BackgroundResearchers are working at unprecedented speed to develop a SARS-CoV-2 vaccine. We aimed to assess the value of a hypothetical vaccine and its potential public health impact when prioritization is required due to supply constraints.MethodsA Markov cohort model was used to estimate COVID-19 related direct medical costs and deaths in the United States (US), with and without implementation of a 60% efficacious vaccine. To prioritize the vaccine under constrained supply, the population was divided into tiers based on age; risk and age; and occupation and age; and outcomes were compared across one year under various supply assumptions. The incremental cost per quality-adjusted life-year (QALY) gained versus no vaccine was calculated for the entire adult population and for each tier in the three prioritization schemes.ResultsThe incremental cost per QALY gained for the US adult population was $8,200 versus no vaccination. For the tiers at highest risk of complications from COVID-19, such as those ages 65 years and older, vaccination was cost-saving compared to no vaccination. The cost per QALY gained increased to over $94,000 for those with a low risk of hospitalization and death following infection. Results were most sensitive to infection incidence, vaccine price, the cost of treating COVID-19, and vaccine efficacy. Under the most optimistic supply scenario, the hypothetical vaccine may prevent 31% of expected deaths. As supply becomes more constrained, only 23% of deaths may be prevented. In lower supply scenarios, prioritization becomes more important to maximize the number of deaths prevented.ConclusionsA COVID-19 vaccine is predicted to be good value for money (cost per QALY gained <$50,000). The speed at which an effective vaccine can be made available will determine how much morbidity and mortality may be prevented in the US.  相似文献   
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Background

Penetrating stab wounds in children are relatively rare and no clear recommendations for the optimal evaluation have been devised. An acceptable traditional approach to the patient with an abdominal stab wound who does not require urgent surgery is selective nonoperative management and serial exams. The use of routine computed tomography remains an actively utilized investigation for these patients at many institutions.

Purpose

We hypothesize that the approach to pediatric stab wound victims should be distinctly different than that of adult counterparts in order to minimize radiation exposure.

Methods

A retrospective cohort study involving abdominal stab wounds among pediatric trauma patients (age < 14) compared with adults between the years 1997 and 2016 was conducted utilizing the Israeli National Trauma Registry.

Results

A total of 92 children and 4444 adults were identified from the registry for inclusion. Among the children 20 (21.7%) patients had intraabdominal injury compared to 1730 (38.9%) among adult counterparts. Four children were hemodynamically unstable, two of them were referred directly to operating room and two others were treated without surgery. Among the remaining 88 children there was no observed mortality.

Conclusions

The majority of pediatric stab wounds trauma victims have minor abdominal injuries. We do not recommend the routine utilization of abdominal CT scan in the evaluation of abdominal stab wounds. Observation with serial exams and minimization of radiation exposure from CT are warranted in this unique population.

Type of study

Retrospective comparative study.

Level of evidence

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In insight problem solving solutions with AHA! experience have been assumed to be the consequence of restructuring of a problem which usually takes place shortly before the solution. However, evidence from priming studies suggests that solutions with AHA! are not spontaneously generated during the solution process but already relate to prior subliminal processing. We test this hypothesis by conducting an fMRI study using a modified compound remote associates paradigm which incorporates semantic priming. We observe stronger brain activity in bilateral anterior insulae already shortly after trial onset in problems that were later solved with than without AHA!. This early activity was independent of semantic priming but may be related to other lexical properties of attended words helping to reduce the amount of solutions to look for. In contrast, there was more brain activity in bilateral anterior insulae during solutions that were solved without than with AHA!. This timing (after trial start/during solution) x solution experience (with/without AHA!) interaction was significant. The results suggest that (a) solutions accompanied with AHA! relate to early solution‐relevant processing and (b) both solution experiences differ in timing when solution‐relevant processing takes place. In this context, we discuss the potential role of the anterior insula as part of the salience network involved in problem solving by allocating attentional resources.  相似文献   
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Purpose: Pelvic fracture evaluation with abdominopelvic computed tomography (CT) and formal CT cystography for rule out of urine bladder injury have been commonly employed in pediatric trauma patients. The additional delayed imaging required to obtain optimal CT cystography is, however, associated with increased doses of ionizing radiation to pelvic organs and represent a significant risk in the pediatric population for future carcinogenic risk. We hypothesized that avoidance of routine CT cystography among pediatric pelvic fracture victims would not result in an appreciable rate of missed bladder injuries and would aid in mitigating the radiation exposure risk associated with these additional images. Methods: A retrospective cohort study involving blunt trauma pelvic fractures among pediatric trauma patients (age<14) between the years 1997 and 2016 was conducted utilizing the Israeli National Trauma Registry. Statistical analysis was performed using SAS statistical software version 9.4 via the tests of Chisquare test and two-sided Fisher''s exact test. A p value of less than 0.05 was considered statistically significant. Results: A total of 1072 children were identified from the registry for inclusion. Mean age of patients was 7.7 years (range 0-14) and 713 (66.5%) were male. Overall mortality in this population was 4.1% (44/1072). Only 2.1% (23) of pediatric patients with pelvic fractures had bladder injury identified, with just 9 children having intraperitoneal bladder rupture (0.8% of all the patients). Conclusion: The vast majority of blunt pediatric trauma victims with pelvic fractures do not have urine bladder injuries. Based on our study results we do not recommend the routine utilization of CT cystography in this unique population.  相似文献   
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