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SARS-CoV-2 variants of concern (VOCs) have caused a significant increase in infections worldwide. Despite high vaccination rates in industrialized countries, the fourth VOC, Omicron, has outpaced the Delta variant and is causing breakthrough infections in individuals with two booster vaccinations. While the magnitude of morbidity and lethality is lower in Omicron, the infection rate and global spread are rapid. Using a specific IgG multipanel-ELISA with the spike protein’s receptor-binding domain (RBD) from recombinant Alpha, Gamma, Delta, and Omicron variants, sera from health-care workers from the Medical University of Vienna were tested pre-pandemic and post-vaccination (BNT162b2; ChAdOx1 nCoV-19). The cohort was continuously monitored by SARS-CoV-2 testing and commercial nucleocapsid IgG ELISA. RBD IgG ELISA showed significantly lower reactivity against the Omicron-RBD compared to the Alpha variant in all individuals (p < 0.001). IgG levels were independent of sex, but were significantly higher in BNT162b2 recipients <45 years of age for Alpha, Gamma, and Delta (p < 0.001; p = 0.040; p = 0.004, respectively). Pre-pandemic cross-reactive anti-Omicron IgG was detected in 31 individuals and was increased 8.78-fold after vaccination, regardless of vaccine type. The low anti-RBD Omicron IgG level could explain the breakthrough infections and their presence could also contribute to a milder COVID-19 course by cross-reactivity and broadening the adaptive immunity.  相似文献   
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A random, population-based sample of 431 women aged 18–74 in King County, Washington, USA, completed a survey module on Internet use and access. Level of mental health, level of general health perceptions, older age, and higher income predicted women's health-related Internet use. Participants without access reported various barriers to obtaining access; perceived lack of usefulness of the Internet as an information source and unfamiliarity with using this technology appear equally important reasons as financial cost for not adopting the Internet. Internet use motivators are complex; these findings have relevance to the design of Internet-based interventions.  相似文献   
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Research in the field of operations management and medicine analyzed how workload affects productivity and patient outcomes. However, staff quality has largely been neglected, and if staffing information has indeed been included, then it takes the form of quantitative measures like staff–to–patient ratios. We therefore seek to analyze how education and experience are directly associated with effort. How do responses to workload differ with respect to education and experience? By analyzing a single hospital unit, we are able to establish a link between staff quality and patient outcomes, allowing us to demonstrate empirically that knowledge and experience are highly relevant in staff members’ responses to increasing system load. The systematic aligning of staffing with expected system load should therefore consider not only staffing quantity but also staffing quality. Provided with a reliable prediction of system load, this knowledge would allow managers to generate savings since they can assign high-quality staff more effectively.  相似文献   
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A simple, rapid method was developed for the determination of in vitro alveolar macrophage viability after exposure to gases. Air pollutants such as ozone, sulfur dioxide, and oxides of nitrogen killed alveolar macrophages, as determined by the dye exclusion test. Ozone (O3) was effective at very low concentrations. Other gases such as carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), methyl chloride (CH3Cl), acrolein, acetaldehyde, acetone, isoprene, benzene, and hydrocyanic acid (HCN) had no effect on cell viability.  相似文献   
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Diagnosis and treatment of primary sclerosing cholangitis   总被引:1,自引:0,他引:1  
PSC is a progressive chronic hepatobiliary disorder of unknown etiology for which no effective medical or surgical therapy now exists. This syndrome occurs most commonly in young men and is frequently associated with CUC. The diagnosis is best made utilizing endoscopic retrogradecopic retrograde cholangiography. Although liver histologic findings alone are infrequently diagnostic of PSC, it remains important to exclude other causes of chronic cholestasis. Although the etiology remains unknown, preliminary studies suggest that PSC is related to immunologic damage. Although viral infections can induce obliterative cholangitis in children, their role in the cause of PSC remains undefined. PSC progresses slowly from an asymptomatic stage to cirrhosis, portal hypertension, and premature death secondary to liver failure. Bile duct cancer appears to be a frequent complication of long-standing PSC. Since no therapy is of established efficacy, controlled clinical trials of both medical and surgical therapy should be encouraged. Fat-soluble vitamin deficiencies commonly occur in the advanced stages of PSC, and therefore serum levels of vitamins A, D, E, and prothrombin time should be monitored on a regular basis to prevent complications associated with these deficiencies. Liver transplantation is now a therapeutic option for the treatment of end-stage PSC. Palliative surgical biliary drainage procedures, proctocolectomy, and surgical decompressive shunts that increase the risk of liver transplants, therefore, should be avoided, if possible, in young PSC patients. If a total proctocolectomy is surgically indicated, we would strongly recommend performing a ileoanal pull-through procedure, thus, avoiding the formation of an abdominal ileostoma and the risk of developing bleeding peristomal varices.  相似文献   
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OBJECTIVES: Prevalence of abdominal aortic aneurysms (AAA) is not exactly known among patients with coronary artery disease (CAD) who are considered for surgical revascularisation. We evaluated the value of screening AAA among coronary patients admitted in our cardiovascular surgery unit. METHODS: Over a 24-month period, an abdominal echography was proposed to male patients aged 60 or more while hospitalised for surgical coronary revascularisation. Patients with previous investigation of the aorta were excluded. The aorta was considered aneurysmal when the anterior-posterior diameter was of 30 mm or more. RESULTS: Three hundred and ninety-five consecutive patients all accepted a proposed abdominal echographic screening for AAA. Forty unsuspected AAA were detected (10.1%). The mean diameter was 38.9 +/- 1.3 mm. Four AAA were larger than 50 mm and considered for surgery after the CABG procedure. Surveillance was proposed to the other 36, especially the 10 patients with an AAA larger than 40 mm. Patients with AAA were significantly older than those without AAA (71.3 +/- 0.8 vs. 69.4 +/- 0.3 years, P<0.05). Smoking history (P<0.05) and hypertension (P<0.05) were also associated more frequently with AAA. More than 16% of the patients being smokers and suffering hypertension presented with unsuspected AAA. CONCLUSIONS: In-hospital screening of AAA is very efficient among patients with coronary artery disease. Therefore, patients with CAD may be considered for routine AAA screening.  相似文献   
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