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Immunologic Research - EBV infection has long been suspected to play a role in the development of autoimmune diseases. Interestingly, a recently published study has provided the strongest evidence...  相似文献   
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BACKGROUND Coronavirus disease 2019(COVID-19) significantly affected endoscopy practice,as gastrointestinal endoscopy is considered a risky procedure for transmission of infection to patients and personnel of endoscopy units(PEU).AIM To assess the impact of COVID-19 on endoscopy during the first European lockdown(March-May 2020).METHODS Patients undergoing endoscopy in nine endoscopy units across six European countries during the period of the first European lockdown for COVID-19(MarchMay 2020) were included. Prior to the endoscopy procedure, participants were stratified as low-or high-risk for potential COVID-19 infection according to the European Society of Gastrointestinal Endoscopy(ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates(ESGENA) joint statement, and contacted 7-14 d later to assess COVID-19 infection status. PEU were questioned regarding COVID-19 symptoms and/or infection via questionnaire, while information regarding hospitalizations, intensive care unitadmissions and COVID-19-related deaths were collected. The number of weekly endoscopies at each center during the lockdown period was also recorded.RESULTS A total of 1267 endoscopies were performed in 1222 individuals across nine European endoscopy departments in six countries. Eighty-seven(7%) were excluded because of initial positive testing. Of the 1135 pre-endoscopy low risk or polymerase chain reaction negative for COVID-19, 254(22.4%) were tested post endoscopy and 8 were eventually found positive, resulting in an infection rate of 0.7% [(95%CI: 0.2-0.12]. The majority(6 of the 8 patients, 75%) had undergone esophagogastroduodenoscopy. Of the 163 PEU, 5 [3%;(95%CI: 0.4-5.7)] tested positive during the study period. A decrease of 68.7%(95%CI: 64.8-72.7) in the number of weekly endoscopies was recorded in all centers after March 2020. All centers implemented appropriate personal protective measures(PPM) from the initial phases of the lockdown.CONCLUSION COVID-19 transmission in endoscopy units is highly unlikely in a lockdown setting, provided endoscopies are restricted to emergency cases and PPM are implemented.  相似文献   
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Neurosurgical Review - Direct delivery of antibiotics to the ventricular system offers an alternative for the management of nosocomial meningitis. However, the available literature frequently...  相似文献   
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ABSTRACT

Introduction

Type 1 diabetes mellitus (T1DM) is a chronic, autoimmune disease that is characterized by total absence of insulin production. Hypertension is a common comorbidity in T1DM with complex pathophysiology, while it is also a well-recognized risk factor for the development of cardiovascular disease (CVD), as well as other microvascular diabetic complications.  相似文献   
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Background/objectivesTo investigate the association between optical coherence tomography (OCT) markers of lesion activity and changes in visual acuity (VA) during anti-vascular endothelial growth factor (anti-VEGF) therapy of eyes diagnosed with neovascular age-related macular degeneration (nAMD); and how VA and OCT markers are considered in physicians’ decision to retreat with anti-VEGFs.Subjects/methodsRetrospective, non-comparative, non-randomised cohort study involving electronic medical record data collected from 1190 patient eyes with nAMD diagnosis at two sites in the United Kingdom. Two sub-cohorts consisting of 321 and 301 eyes, respectively, were selected for analyses.ResultsIn 321 eyes, absence of IRF or SRF at ≥2 clinic visits resulted in a gain of five ETDRS letters from baseline, compared with two letters gained in eyes with <2 clinic visits with absence of IRF (p = 0.006) or SRF (p = 0.042). Anti-VEGF treatment was administered at 421 clinic visits, and 308 visits were without treatment. Comparing treatment visits with non-treatment visits, the maximum difference in frequency of OCT markers of lesion activity were for intraretinal fluid (IRF; 24% versus 5%) and subretinal fluid (SRF; 32% versus 5%). Pigment epithelial detachment (PED) was reported in 58% of treatment visits compared with 36% in non-treatment visits. VA loss was not a consistent trigger for retreatment as it was present in 63% of injection visits and in 49% of non-injection visits.ConclusionsRetreatment decision making is most strongly influenced by the presence of IRF and SRF and less by the presence of PED or VA loss.Subject terms: Outcomes research, Macular degeneration  相似文献   
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Bone vasculature and bone marrow vascular niches supply oxygen, nutrients, and secrete angiocrine factors required for the survival, maintenance, and self-renewal of stem and progenitor cells. In the skeletal system, vasculature creates nurturing niches for bone and blood-forming stem cells. Blood vessels regulate hematopoiesis and drive bone formation during development, repair, and regeneration. Dysfunctional vascular niches induce skeletal aging, bone diseases, and hematological disorders. Recent cellular and molecular characterization of the bone marrow microenvironment has provided unprecedented insights into the complexity, heterogeneity, and functions of the bone vasculature and vascular niches. The bone vasculature is composed of distinct vessel subtypes that differentially regulate osteogenesis, hematopoiesis, and disease conditions in bones. Further, bone marrow vascular niches supporting stem cells are often complex microenvironments involving multiple different cell populations and vessel subtypes. This review provides an overview of the emerging vascular cell heterogeneity in bone and the new roles of the bone vasculature and associated vascular niches in health and disease. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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