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Background contextSpinal cord injuries (SCIs) related to cervical spine (C-spine) fractures can cause significant morbidity and mortality. Aggressive treatment often required to manage instability associated with C-spine fractures is complicated and hazardous in the elderly population.PurposeTo determine the mortality rate of elderly patients with SCIs related to C-spine fractures and identify factors that contribute toward a higher risk for negative outcomes.Study design/settingRetrospective cohort study at two Level 1 trauma centers.Patient sampleThirty-seven consecutive patients aged 60 years and older who had SCIs related to C-spine fractures.Outcome measuresLevel of injury, injury severity, preinjury medical comorbidities, treatment (operative vs. nonoperative), and cause of death.MethodsHospital medical records were reviewed independently. Baseline radiographs and computed tomography or magnetic resonance imaging scans were examined to permit categorization according to the mechanistic classification by Allen and Ferguson of subaxial C-spine injuries. Univariate logistic regression analyses were performed to identify factors related to in-hospital mortality and ambulation at discharge. There were no funding sources or potential conflicts of interest to disclose.ResultsThe in-hospital mortality rate was 38%. Respiratory failure was the leading cause of death. Preinjury medical comorbidities, age, and operative versus nonoperative treatment did not affect mortality. Injury level at or above C4 was associated with a 7.1 times higher risk of mortality compared with injuries below C4 (p=.01). Complete SCI was associated with a 5.1 times higher risk of mortality compared with incomplete SCI (p=.03). Neurological recovery was uncommon. Apart from severity of initial SCI, no other factor was related to ambulatory disposition at discharge.ConclusionsIn this elderly population, neurological recovery was poor and the in-hospital mortality rate was high. The strongest risk factors for mortality were injury level and severity of SCI. Although each case of SCI related to C-spine fractures is different, physicians may be able to use these findings to help better determine the prognosis and guide subsequent treatment.  相似文献   
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In this article, we consider the optimal topology design and distributed formation control problem of multiagent systems (MAS) with complex-weighted directed topology. First, a framework is proposed to associate optimal topology of MAS to a constrained optimization problem with a complex Laplacian matrix, which is independent of the agent dynamics. The main contribution of the proposed approach compared with existing results is that the proposed approach does not require the calculation of the stabilizing matrix such that the closed-loop system is asymptotically stable, and a unique set of complex weights that satisfy associated cooperative conditions can be chosen. Then, a distributed formation control protocol is proposed to enable all agents to achieve the control goal. Finally, some numerical example results are provided to demonstrate the effectiveness of the proposed scheme.  相似文献   
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Free clinics provide free primary care to the under or uninsured and have been playing an important role in serving the socio-economically disadvantaged. Free clinic patients represent a group of people who experience significant barriers to receiving diabetes prevention and intervention. This study examined diabetes attitudes among free clinic patients and volunteers. English or Spanish speaking patients and volunteers (N = 384), aged 18 years or older completed a self-administered survey. Diabetic patients and volunteers shared similar levels of diabetes attitudes compared to non-diabetic patients. Among patients, ethnicity, education level, diabetes education, and family history affected diabetes attitudes. Among volunteers, diabetes education was an important factor associated with positive diabetes attitudes. Whether the volunteer is a healthcare professional or student was related only to one aspect of diabetes attitudes, seriousness of type 2 diabetes. The results, indicating free clinic diabetic patients and volunteers shared similar levels of diabetes attitudes, were positive for maintaining and developing diabetes education programs at a free clinic. Unfortunately, the average length of volunteering at this free clinic was short and student volunteers likely leave the clinic upon graduation. Future research should examine issues of volunteer retention in free clinics. Diabetes education for patients may need to be diversified according to ethnicity, family history of diabetes, and educational level. Finally, non-healthcare professional volunteers could potentially be involved in diabetes education at a free clinic.  相似文献   
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Introduction and hypothesis

One of the main outcomes in the assessment of the treatment of pelvic organ prolapse in women is quality of life. Using quality of life as an outcome measure is increasing in the majority of clinical trials. The aim of current study was to determine the effects of the treatment of pelvic organ prolapse on patients’ quality of life using systematic review and meta-analysis.

Methods

A systematic search for finding randomized controlled studies on pelvic organ prolapse published before October 2012 was conducted. The JAMA users’ guide to the medical literature quality assessment scales for randomized clinical trials was used to assess the quality of included articles. The mean difference in total quality of life score between before and after intervention (surgical or pelvic floor training) with 95 % confidence interval (CI) was considered as a primary summary measure. Egger’s test was used to evaluate the publication bias. Heterogeneity was assessed using I2 Index.

Results

Fifty-seven RCT were critically appraised. Thirty-two articles were eligible after critical evaluation. Mean difference in change in the total quality of life score with 95 % CI for surgical treatment was 74.03 (66.3–81.6) by PFDI-20 and was 44.57 (22.53–66.65) by PFIQ-7. The mean difference in changed in the total quality of life score with 95 % CI was 1.32 (?2.8–5.4) for pelvic floor training (PFT).

Conclusion

We found that surgical interventions on prolapse can improve the quality of life of women. There was a relative effect of PFT on the quality of life of women with prolapse in systematic review. This effect was not seen in meta-analysis, probably because of finding few eligible studies to pool the effect size.  相似文献   
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Deep learning-based computer vision methods have recently made remarkable breakthroughs in the analysis and classification of cancer pathology images. However, there has been relatively little investigation of the utility of deep neural networks to synthesize medical images. In this study, we evaluated the efficacy of generative adversarial networks to synthesize high-resolution pathology images of 10 histological types of cancer, including five cancer types from The Cancer Genome Atlas and the five major histological subtypes of ovarian carcinoma. The quality of these images was assessed using a comprehensive survey of board-certified pathologists (n = 9) and pathology trainees (n = 6). Our results show that the real and synthetic images are classified by histotype with comparable accuracies and the synthetic images are visually indistinguishable from real images. Furthermore, we trained deep convolutional neural networks to diagnose the different cancer types and determined that the synthetic images perform as well as additional real images when used to supplement a small training set. These findings have important applications in proficiency testing of medical practitioners and quality assurance in clinical laboratories. Furthermore, training of computer-aided diagnostic systems can benefit from synthetic images where labeled datasets are limited (e.g. rare cancers). We have created a publicly available website where clinicians and researchers can attempt questions from the image survey ( http://gan.aimlab.ca/ ). © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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