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Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis.  相似文献   
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The Zarit Burden Interview has been the most popularly used tool for measuring caregiver burden and with the 60 years and over population in Jamaica and developing countries expected to increase, caregiver burden and its assessment assume increased importance. Establishing the reliability and underlying factor structure of instruments such as the ZBI is critical. This study sought to determine the reliability of the Zarit Burden Interview and to assess its underlying factor structure. The ZBI was administered to 180 caregivers of community dwelling older persons in Jamaica in a nationally representative sample across four geographic health regions in 2016. The factor structure was identified using exploratory factor analysis (EFA) with Varimax rotation. Cronbach's alpha was used to assess internal consistency/reliability of the instrument. The internal consistency/reliability of the ZBI instrument was high (Cronbach's α = 0.859) and the corrected item-total correlations ranged from 0.134 to 0.730. The ZBI mean score was found to be 16.92 ± 12.04. EFA produced a six-factor model comprised of 19 items which explained 48.97% of total variance, and was subsequently reduced to four (37.27% of total variance) via the use of parallel analysis and scrutiny of confidence intervals. The four factors identified were ‘personal strain’, ‘social relations disruption’, ‘resource strain/imbalance’ and ‘role intensity’. The ZBI-22 tool is a reliable instrument for evaluating caregiver burden among community dwelling older persons in Jamaica. A four factor model has emerged providing greater insights on the underlying constructs of the ZBI, the most widely used caregiver burden assessment tool.  相似文献   
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PURPOSE: We have demonstrated previously that a mixture of three anti-Her-2 monoclonal antibodies (MAbs) that bind to different epitopes on the extracellular domain of Her-2 expressed on a human breast cancer cell line has more potent antitumor activity than the individual MAbs both in vitro and in xenografted severe combined immunodeficient mice. Because the activity of Herceptin is Fc dependent, we determined whether this would also be the case when a mixture of these three anti-Her-2 MAbs was used. EXPERIMENTAL DESIGN: IgG and highly purified F(ab')(2) fragments of the anti-Her-2 MAbs and Herceptin were prepared and evaluated for their ability to induce cell death, inhibit vascular endothelial growth factor secretion, and mediate antibody-dependent cellular cytotoxicity and complement-mediated cytotoxicity in vitro. They were also compared for their abilities to induce regression of large BT474 tumors in severe combined immunodeficient mice. RESULTS: All of the F(ab')(2) fragments were >95% pure and, as expected, did not mediate antibody-dependent cellular cytotoxicity or complement-dependent cytotoxicity in vitro. The in vitro antiproliferative and proapoptotic effects of the IgGs and F(ab')(2) fragments were similar. In contrast, the IgGs had significant antitumor activity in vivo, whereas their F(ab')(2) fragments were only marginally effective even at 5-fold higher doses to offset their shorter half-lives. CONCLUSIONS: These results confirm the importance of the Fc portion of Herceptin for optimal in vivo activity and demonstrate that even a mixture of three anti-Her-2 MAbs that are highly effective at inducing cell death in vitro requires Fc-mediated effector function for optimal in vivo activity.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - The purpose of this study is to share our experience on the use of different orbital decompression techniques, as well as the...  相似文献   
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Given the availability of genotype and phenotype data collected in family members, the question arises which estimator ensures the most optimal use of such data in genome-wide scans. Using simulations, we compared the Unweighted Least Squares (ULS) and Maximum Likelihood (ML) procedures. The former is implemented in Plink and uses a sandwich correction to correct the standard errors for model misspecification of ignoring the clustering. The latter is implemented by fast linear mixed procedures and models explicitly the familial resemblance. However, as it commits to a background model limited to additive genetic and unshared environmental effects, it employs a misspecified model for traits with a shared environmental component. We considered the performance of the two procedures in terms of type I and type II error rates, with correct and incorrect model specification in ML. For traits characterized by moderate to large familial resemblance, using an ML procedure with a correctly specified model for the conditional familial covariance matrix should be the strategy of choice. The potential loss in power encountered by the sandwich corrected ULS procedure does not outweigh its computational convenience. Furthermore, the ML procedure was quite robust under model misspecification in the simulated settings and appreciably more powerful than the sandwich corrected ULS procedure. However, to correct for the effects of model misspecification in ML in circumstances other than those considered here, we propose to use a sandwich correction. We show that the sandwich correction can be formulated in terms of the fast ML method.  相似文献   
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Purpose

To test the effectiveness of a central venous catheter (CVC) insertion strategy and a hand hygiene (HH) improvement strategy to prevent central venous catheter-related bloodstream infections (CRBSI) in European intensive care units (ICUs), measuring both process and outcome indicators.

Methods

Adult ICUs from 14 hospitals in 11 European countries participated in this stepped-wedge cluster randomised controlled multicentre intervention study. After a 6 month baseline, three hospitals were randomised to one of three interventions every quarter: (1) CVC insertion strategy (CVCi); (2) HH promotion strategy (HHi); and (3) both interventions combined (COMBi). Primary outcome was prospective CRBSI incidence density. Secondary outcomes were a CVC insertion score and HH compliance.

Results

Overall 25,348 patients with 35,831 CVCs were included. CRBSI incidence density decreased from 2.4/1000 CVC-days at baseline to 0.9/1000 (p < 0.0001). When adjusted for patient and CVC characteristics all three interventions significantly reduced CRBSI incidence density. When additionally adjusted for the baseline decreasing trend, the HHi and COMBi arms were still effective. CVC insertion scores and HH compliance increased significantly with all three interventions.

Conclusions

This study demonstrates that multimodal prevention strategies aiming at improving CVC insertion practice and HH reduce CRBSI in diverse European ICUs. Compliance explained CRBSI reduction and future quality improvement studies should encourage measuring process indicators.
  相似文献   
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