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排序方式: 共有10000条查询结果,搜索用时 62 毫秒
991.
Giovanni Maconi Cristina Bosetti Alberta De Monti Ray Kiran Boyapati Edward Shelton Nicole Piazza Anna Maria Carvalhas Gabrielli Marco Vincenzo Lenti Cristina Bezzio Chiara Ricci Salvatore Greco Samanta Romeo Francesco Giangregorio Daniele Gridavilla Fabio Tagliani Alessandro Massari Luca Pastorelli Antonio Di Sabatino Sandro Ardizzone 《Digestive and liver disease》2021,53(3):263-270
BackgroundIt is unclear whether patients with inflammatory bowel disease (IBD) are at increased risk of COVID-19.ObjectivesThis observational study compared the prevalence of COVID-19 symptoms, diagnosis and hospitalization in IBD patients with a control population with non-inflammatory bowel disorders.MethodsThis multicentre study, included 2733 outpatients (1397 IBD patients and 1336 controls), from eight major gastrointestinal centres in Lombardy, Italy. Patients were invited to complete a web-based questionnaire regarding demographic, historical and clinical features over the previous 6 weeks. The prevalence of COVID-19 symptoms, diagnosis and hospitalization for COVID-19 was assessed.Results1810 patients (64%) responded to the questionnaire (941 IBD patients and 869 controls). IBD patients were significantly younger and of male sex than controls. NSAID use and smoking were more frequent in controls. IBD patients were more likely treated with vitamin-D and vaccinated for influenza. Highly probable COVID-19 on the basis of symptoms and signs was less frequent in the IBD group (3.8% vs 6.3%; OR:0.45, 95%CI:0.28–0.75). IBD patients had a lower rate of nasopharyngeal swab-PCR confirmed diagnosis (0.2% vs 1.2%; OR:0.14, 95%CI:0.03–0.67). There was no difference in hospitalization between the groups (0.1% vs 0.6%; OR:0.14, 95%CI:0.02–1.17).ConclusionIBD patients do not have an increased risk of COVID-19 specific symptoms or more severe disease compared with a control group of gastroenterology patients. 相似文献
992.
Riccardo Marmo Marco Soncini Cristina Bucci Angelo Zullo 《Digestive and liver disease》2021,53(1):102-106
Background/AimThe indiscriminate use of high-dose, proton pump inhibitor (PPI) infusion in non-variceal upper gastrointestinal bleeding (UGIB) patients to reduce the rate of peptic ulcers with high-risk stigmata (HRS) has been questioned. We evaluated the prevalence of HRS on peptic ulcer and non-ulcer lesions in patients receiving or not receiving pre-endoscopic PPI therapy.MethodsData of consecutive UGIB patients observed in 50 Italian centres were analysed. The prevalence of both HRS on peptic ulcers and active bleeding on non-ulcer lesions between patients treated or not treated with PPI were compared. Multivariate analysis was performed.ResultsA total of 1,792 (69.8%) out of 2,566 patients received PPI therapy. Prevalence of HRS on ulcers was 51.8% and 53.4% (P = 0.58) in treated and not treated patients, respectively, and the rate of endoscopic therapy did not differ between groups. Prevalence of non-ulcer bleeding lesions was higher in patients treated than in those not treated with PPI (18.7% vs 10.6%; P = 0.023). At multivariate analysis, PPI therapy (OR: 1.16, 95% CI = 0.82–1.64; P = 0.4) was not an independent factor affecting HRS prevalence, which was inversely correlated with timing to endoscopy (OR: 0.85, 95% CI = 0.76–0.95; P = 0.005).ConclusionsOur data failed to detect a significant role of pre-endoscopic PPI therapy in decreasing prevalence of HRS and need for endoscopic treatment in bleeding patients with either peptic ulcer or non-ulcer lesions. 相似文献
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995.
Pedro Ferreira Brbara Abreu Cristina Freire Diana M. Fernandes Eduardo F. Marques 《Materials》2021,14(4)
Fuel cells are emerging devices as clean and renewable energy sources, provided their efficiency is increased. In this work, we prepared nanocomposites based on multiwalled carbon nanotubes (MWNTs) and transition metal dichalcogenides (TMDs), namely WS2 and MoS2, and evaluated their performance as electrocatalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR), relevant to fuel cells. The one- and two-dimensional (1D and 2D) building blocks were initially exfoliated and non-covalently functionalized by surfactants of opposite charge in aqueous media (tetradecyltrimethylammonium bromide, TTAB, for the nanotubes and sodium cholate, SC, for the dichalcogenides), and thereafter, the three-dimensional (3D) MoS2@MWNT and WS2@MWNT composites were assembled via surfactant-mediated electrostatic interactions. The nanocomposites were characterized by scanning electron microscopy (SEM) and structural differences were found. WS2@MWNT and MoS2@MWNT show moderate ORR performance with potential onsets of 0.71 and 0.73 V vs. RHE respectively, and diffusion-limiting current densities of −1.87 and −2.74 mA·cm−2, respectively. Both materials present, however, better tolerance to methanol crossover when compared to Pt/C and good stability. Regarding OER performance, MoS2@MWNT exhibits promising results, with η10 and jmax of 0.55 V and 17.96 mA·cm−2, respectively. The fabrication method presented here is cost-effective, robust and versatile, opening the doors for the optimization of electrocatalysts’ performance. 相似文献
996.
997.
998.
Allain JP Candotti D Soldan K Sarkodie F Phelps B Giachetti C Shyamala V Yeboah F Anokwa M Owusu-Ofori S Opare-Sem O 《Blood》2003,101(6):2419-2425
The risk of hepatitis B virus (HBV) transmission by transfusion in sub-Saharan Africa is considered to be relatively low, and testing of blood donors is often not done or is done relatively poorly. To re-examine this attitude, we identified HBV chronically infected blood donors from a major hospital in Ghana with a range of hepatitis B surface antigen (HBsAg) assays. Test efficacy was estimated using HBV DNA as a gold standard, and the risk of HBV infection in blood recipients was estimated for different testing strategies. Particle agglutination, dipstick, and enzyme immunoassay (EIA) HBsAg screening detected 54%, 71%, and 97% of HBV infectious donors, respectively. The risk of HBV transmission to recipients less than 10 years old ranged between 1:11 and 1:326 with blood unscreened and screened by EIA, respectively. For older recipients, the risk decreased a further 4-fold because of the high frequency of natural exposure to HBV. A total of 98% of HBsAg-confirmed positive samples contained HBV DNA. HBV DNA load was less than 1 x 10(4) IU/mL in 75% of HBsAg-reactive samples, most of them anti-HBe reactive. Approximately 0.5% of HBsAg-negative but anti-HBc-positive samples contained HBV DNA. The use of sensitive HBsAg tests is critical to prevent transfusion transmission of HBV infection to young children in a population with a 15% prevalence of chronic HBV infection in blood donors. However, this will not have much effect on the prevalence of this infection unless other strategies to protect children from infection are also advanced in parallel. 相似文献
999.
1000.
Galbusera M Bresin E Noris M Gastoldi S Belotti D Capoferri C Daina E Perseghin P Scheiflinger F Fakhouri F Grünfeld JP Pogliani E Remuzzi G 《Blood》2005,106(3):925-928
Thrombotic thrombocytopenic purpura (TTP) is a rare disorder of small vessels that is associated with deficiency of the von Willebrand factor-cleaving protease, ADAMTS13. The presence of anti-ADAMTS13 autoantibodies is considered a factor predisposing to relapses. Despite close monitoring and intensive plasma treatment, in these patients acute episodes are still associated with substantial morbidity and mortality rates, and the optimal therapeutic option should be prevention of relapses. This study was conducted in a patient with recurrent TTP due to high titers of ADAMTS13 inhibitors, who used to have 2 relapses of TTP a year. The study compared the standard treatment plasma exchange with rituximab. Results documented that plasma exchange had only a small transient effect on ADAMTS13 activity and inhibitors; on the contrary, prophylaxis with rituximab was associated with disappearance of anti-ADAMTS13 antibodies, a progressive recovery of protease activity, and it allowed the patient to maintain a disease-free state during a more than 2-year follow-up. 相似文献