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991.
BackgroundRapid reduction of ileocolic intussusception is important to minimize the compromise in blood flow to the affected bowel segment. This study aimed to quantify the potentially modifiable time between diagnosis and initiation of pneumatic reduction, identify factors associated with delays, and characterize the outcomes of pneumatic reduction in a recent cohort.MethodsThis retrospective observational study occurred at a tertiary care paediatric hospital with a consecutive sample of all children with ileocolic intussusception September 2015 through September 2018. The primary outcome was the time between ultrasound diagnosis of intussusception and the beginning of pneumatic reduction. Independent variables were age of the patient, time of day of arrival, transfer from another facility, and intravenous access prior to ultrasound. Outcomes of pneumatic reduction were expressed as proportions.ResultsThere were 103 cases of ileocolic intussusception (among 257,282 visits) during the study period. The median time between diagnostic confirmation and initiation of reduction was 36 minutes. This was shorter for transferred patients and children with intravenous access prior to ultrasound. One perforation was identified at the beginning of reduction, without hemodynamic instability. Six children (5.8%) underwent either open (n=4) or laparoscopic surgery (n=2) for reduction failure.ConclusionThe median delay between diagnosis and initiation of reduction at this paediatric hospital was short, especially among patients transferred with a suspicion of intussusception and children with intravenous access prior to diagnosis. Complications from pneumatic reduction were infrequent.  相似文献   
992.
BackgroundWe carried out a case-control study that examined whether receipt of the inactivated influenza vaccine during the 2019–2020 season impacted on the risk of coronavirus disease 2019 (COVID-19), as there was a concern that the vaccine could be detrimental through viral interference.MethodsA total of 920 cases with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (diagnosed between March and October 2020) and 2,123 uninfected controls were recruited from those who were born in Québec between 1956 and 1976 and who had received diagnostic services at two hospitals (Montréal and Sherbrooke, Québec). After obtaining consent, a questionnaire was administered by phone. Data were analyzed by logistic regression.ResultsAmong healthcare workers, inactivated influenza vaccine received during the previous influenza season was not associated with increased COVID-19 risk (AOR: 0.99, 95% CI: 0.69–1.41). Among participants who were not healthcare workers, influenza vaccination was associated with lower odds of COVID-19 (AOR: 0.73, 95% CI 0.56–0.96).ConclusionWe found no evidence that seasonal influenza vaccine increased the risk of developing COVID-19.  相似文献   
993.
994.
In macaque monkey, frontal and parasagittal brain sections were stained with SMI-32, an antibody directed against a nonphosphorylated neurofilament protein that labels pyramidal cells. The goal of this investigation was to find reliable criteria with which to draw the border between the motor (M1) and premotor (PM) cortex and delineate subdivisions within the lateral PM. Two-dimensional reconstruction of the staining patterns was also performed by flattening the series of frontal sections. The distribution of SMI-32 immunoreactivity in layers III and V of the cortex revealed the existence of three subregions in the ventral rostral PM and a clear mediolateral boundary within the dorsal PM defined by clusters of SMI-32-positive pyramidal cells in layer V. The border between M1 and PM was easily distinguished at the level of the dorsal PM by a strong loss of immunoreactive pyramidal cells in layers III and V. At the level of the ventral PM there was no clear disruption of layer V pattern, and the border was set using the pattern of layer III immunoreactivity. Received: 30 October 1998 / Accepted: 4 March 1999  相似文献   
995.
996.
There are many obstacles to the timely identification of clinical reasoning difficulties in health professions education. This guide aims to provide readers with a framework for supervising clinical reasoning and identifying the potential difficulties as they may occur at each step of the reasoning process.  相似文献   
997.
Meningeal lymphatic vessels (MLVs) were identified in the dorsal and caudobasal regions of the dura mater, where they ensure waste product elimination and immune surveillance of brain tissues. Whether MLVs exist in the anterior part of the murine and human skull and how they connect with the glymphatic system and extracranial lymphatics remained unclear. Here, we used light-sheet fluorescence microscopy (LSFM) imaging of mouse whole-head preparations after OVA-A555 tracer injection into the cerebrospinal fluid (CSF) and performed real-time vessel-wall (VW) magnetic resonance imaging (VW-MRI) after systemic injection of gadobutrol in patients with neurological pathologies. We observed a conserved three-dimensional anatomy of MLVs in mice and humans that aligned with dural venous sinuses but not with nasal CSF outflow, and we discovered an extended anterior MLV network around the cavernous sinus, with exit routes through the foramina of emissary veins. VW-MRI may provide a diagnostic tool for patients with CSF drainage defects and neurological diseases.  相似文献   
998.
Eicosapentaenoic and docosahexaenoic acids have been reported to have a variety of beneficial effects on cardiovascular disease risk factors. However, a large inter-individual variability in the plasma lipid response to an omega-3 (n-3) polyunsaturated fatty acid (PUFA) supplementation is observed in different studies. Genetic variations may influence plasma lipid responsiveness. The aim of the present study was to examine the effects of a supplementation with n-3 PUFA on the plasma lipid profile in relation to the presence of single-nucleotide polymorphisms (SNPs) in the fatty acid desaturase (FADS) gene cluster. A total of 208 subjects from Quebec City area were supplemented with 3 g/day of n-3 PUFA, during six weeks. In a statistical model including the effect of the genotype, the supplementation and the genotype by supplementation interaction, SNP rs174546 was significantly associated (p = 0.02) with plasma triglyceride (TG) levels, pre- and post-supplementation. The n-3 supplementation had an independent effect on plasma TG levels and no significant genotype by supplementation interaction effects were observed. In summary, our data support the notion that the FADS gene cluster is a major determinant of plasma TG levels. SNP rs174546 may be an important SNP associated with plasma TG levels and FADS1 gene expression independently of a nutritional intervention with n-3 PUFA.  相似文献   
999.
RTS,S/AS02A is a pre-erythrocytic vaccine candidate based on the Plasmodium falciparum circumsporozoite surface antigen and is currently the most advanced malaria vaccine candidate in development. A proof of concept phase IIb trial of the RTS,S/AS02A in Mozambican children aged 1-4 years determined a vaccine efficacy against risk of clinical malaria of 35.3% (95% CI 21.6-46.6; p<0.0001) and against severe malaria of 48.6% (95% CI 12.3-71.0; p=0.02). We evaluated the safety of the RTS,S/AS02A vaccine. 2022 children that received at least one vaccine dose of RTS,S/AS02A or control vaccines were included in the intention to treat safety analysis. Vaccine safety was evaluated using active and passive follow-up. Participants were observed for at least 1h after each dose. Trained field workers visited children at home daily for the next 3 days to record solicited and unsolicited local and general symptoms. Investigators followed-up participants with severe adverse events until month 21. Overall, we recorded 1712 unsolicited adverse events after vaccination, 53% in the intervention and 47% in the control group. Most unsolicited adverse events reported with RTS,S/AS02A were self-limited, and participants recovered without sequelae. Local reactogenicity increased with the number of doses. The proportion of children experiencing serious adverse events was lower in the RTS,S/AS02A recipients compared to the control group (Engerix-Btrade mark or Prevnartrade mark and Hiberixtrade mark). Overall, these results indicate that the RTS,S/AS02A vaccine has a good safety profile and well tolerated when given in three doses to semi-immune children living in malaria-endemic areas.  相似文献   
1000.
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