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排序方式: 共有10000条查询结果,搜索用时 15 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
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Carmen Andrade Ana Martínez-Serrano Miguel ngel Sanjun Jos Antonio Tenorio Ríos 《Materials》2021,14(5)
The Portland cement industry is presently deemed to account for around 7.4% of the carbon dioxide emitted annually worldwide. Clinker production is being reduced worldwide in response to the need to drastically lower greenhouse gas emissions. The trend began in the nineteen seventies with the advent of mineral additions to replace clinker. Blast furnace slag and fly ash, industrial by-products that were being stockpiled in waste heaps at the time, have not commonly been included in cements. Supply of these additions is no longer guaranteed, however, due to restrained activity in the source industries for the same reasons as in clinker production. The search is consequently on for other additions that may lower pollutant gas emissions without altering cement performance. In this study, bentonite, a very common clay, was used as such an addition directly, with no need for precalcination, a still novel approach that has been scantly explored to date for reinforced structural concrete with structural applications. The results of the mechanical strength and chemical resistance (to sulfates, carbonation and chlorides) tests conducted are promising. The carbonation findings proved to be of particular interest, for that is the area where cement with mineral additions tends to be least effective. In the bentonite-bearing material analysed here, however, carbonation resistance was found to be as low as or lower than that observed in plain Portland cement. 相似文献
994.
Laguna Benjamin Westphalen Antonio C. Guimarães C. T. Whang Zhen Simko Jeff Zagoria Ronald 《Abdominal imaging》2019,44(4):1430-1452
Abdominal Radiology - While the typical imaging features of the more common RCC subtypes have previously been described, they can at times have unusual, but distinguishing features. Rarer renal... 相似文献
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Cesar Homero Gutirrez‐Aguirre Dalila Marisol Alvarado‐Navarro Alain Palomares‐Leal Gerardo Mejía‐Jaramillo Rosario Salazar‐Riojas Andrs Gmez‐De Len Perla Rocío Colunga‐Pedraza Guillermo Sotomayor‐Duque Jos Carlos Jaime‐Prez Olga Graciela Cantú‐Rodríguez Luz del Carmen Tarín‐Arzaga Juan Antonio Flores‐Jimnez David Gmez‐Almaguer 《Transfusion》2019,59(12):3721-3726
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Valeria Cernaro Giuseppe Coppolino Luca Visconti Laura Rivoli Antonio Lacquaniti Domenico Santoro Antoine Buemi Saverio Loddo Michele Buemi 《Medicinal research reviews》2019,39(2):427-460
Erythropoiesis is triggered by hypoxia and is strictly regulated by hormones, growth factors, cytokines, and vitamins to ensure an adequate oxygen delivery to all body cells. Abnormalities in one or more of these factors may induce different kinds of anemia requiring different treatments. A key player in red blood cell production is erythropoietin. It is a glycoprotein hormone, mainly produced by the kidneys, that promotes erythroid progenitor cell survival and differentiation in the bone marrow and regulates iron metabolism. A deficit in erythropoietin synthesis is the main cause of the normochromic normocytic anemia frequently observed in patients with progressive chronic kidney disease. The present review summarizes the most recent findings about each step of the erythropoietic process, going from the renal oxygen sensing system to the cascade of events induced by erythropoietin through its own receptor in the bone marrow. The paper also describes the new class of drugs designed to stabilize the hypoxia-inducible factor by inhibiting prolyl hydroxylase, with a discussion about their metabolism, disposition, efficacy, and safety. According to many trials, these drugs seem able to simulate tissue hypoxia and then stimulate erythropoiesis in patients affected by renal impairment. In conclusion, the in-depth investigation of all events involved in erythropoiesis is crucial to understand anemia pathophysiology and to identify new therapeutic strategies, in an attempt to overcome the potential side effects of the commonly used erythropoiesis-stimulating agents. 相似文献
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