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Illustrated by a clinical case supplemented by epidemiologic data, early reinfections with SARS-CoV-2 Omicron BA.1 after infection with Delta variant, and reinfection with Omicron BA.2 after Omicron BA.1 infection, can occur within 60 days, especially in young, unvaccinated persons. The case definition of reinfection, which influences retesting policies, should be reconsidered.  相似文献   
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ObjectiveTo investigate COVID-19 vaccine uptake and intent among pregnant people in Canada, and determine associated factors.MethodsWe conducted a national cross-sectional survey among pregnant people from May 28 through June 7, 2021 (n = 193). Respondents completed a questionnaire to determine COVID-19 vaccine acceptance (defined as either received or intend to receive a COVID-19 vaccine during pregnancy), factors associated with vaccine acceptance, and rationale for accepting/not accepting the vaccine.ResultsOf 193 respondents, 57.5% (n = 111) reported COVID-19 vaccine acceptance. Among those who did not accept the vaccine, concern over vaccine safety was the most commonly cited reason (90.1%, n = 73), and 81.7% (n = 67) disagreed with receiving a vaccine that had not been tested in pregnant people. Confidence in COVID-19 vaccine safety (aOR 16.72, 95% CI: 7.22, 42.39), Indigenous self-identification (aOR 11.59, 95% CI: 1.77, 117.18), and employment in an occupation at high risk for COVID-19 exposure excluding healthcare (aOR 4.76, 95% CI: 1.32, 18.60) were associated with vaccine acceptance. Perceived personal risk of COVID-19 disease was not associated with vaccine acceptance in the multivariate model.ConclusionVaccine safety is a primary concern for this population. Safety information should be communicated to this population as it emerges, along with clear messaging on the benefits of vaccination, as disease risk is either poorly understood or poorly valued in this population.  相似文献   
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Pulmonary function tests were performed in 45 patients with scleroderma. Thirteen patients (29%) were found to have restrictive disease, 12 patients (27%) were found to have obstructive disease, and 19 patients (42%) had small airway disease (SAD). Smoking did not seem to be a factor underlying either obstructive or small airway disease in these patients. A low diffusing capacity was most common in patients with restrictive disease and rarely the only abnormality in pulmonary function. SAD was usually found in patients who had normal chest radiographs and no pulmonary symptoms and was often the only abnormality. SAD is therefore an early and sensitive indicator of pulmonary involvement in scleroderma.  相似文献   
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Robotic surgery offers potential technical advantages that may facilitate pancreatic resection. The aim of this study was to evaluate the learning curve and short-term perioperative outcomes in patients who underwent laparoscopic and robot-assisted distal pancreatectomy. All perioperative variables were evaluated and compared retrospectively between laparoscopic (LDP) (n = 23) and robot-assisted (RDP) (n = 11) distal pancreatectomy. The mean total operative time was shorter in LDP (194 vs. 225 min; p = 0.017). All other perioperative criteria were similar between LDP and RDP patients (blood loss, transfusion rate, conversion, pancreatic fistula, postoperative morbidity, and duration of hospitalization). Non-adjusted CUSUM curve for composite events including operative time, conversion, postoperative morbidity and reoperation rates showed that the RDP learning curve corresponded to the first seven consecutive patients. During early experience, RDP was associated with longer operative time but similar short-term perioperative outcomes compared to conventional distal pancreatectomy.  相似文献   
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EGF receptor (EGFR) overexpression is thought to drive head and neck carcinogenesis however clinical responses to EGFR-targeting agents have been modest and alternate targets are actively sought to improve results. Src family kinases (SFKs), reported to act downstream of EGFR are among the alternative targets for which increased expression or activity in epithelial tumors is commonly associated to the dissolution of E-cadherin-based junctions and acquisition of a mesenchymal-like phenotype. Robust expression of total and activated Src was observed in advanced stage head and neck tumors (N=60) and in head and neck squamous cell carcinoma lines. In cultured cancer cells Src co-localized with E-cadherin in cell-cell junctions and its phosphorylation on Y419 was both constitutive and independent of EGFR activation. Selective inhibition of SFKs with SU6656 delocalized E-cadherin and disrupted cellular junctions without affecting E-cadherin expression and this effect was phenocopied by knockdown of Src or Yes. These findings reveal an EGFR-independent role for SFKs in the maintenance of intercellular junctions, which likely contributes to the cohesive invasion E-cadherin-positive cells in advanced tumors. Further, they highlight the need for a deeper comprehension of molecular pathways that drive collective cell invasion, in absence of mesenchymal transition, in order to combat tumor spread.  相似文献   
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