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1.
Knox  Joseph A.  Kumar  Vishal  Conrad  Miles B.  Nanavati  Sujal  Moore  Teri  Wilson  Mark 《Emergency radiology》2022,29(3):605-609
Emergency Radiology - Access to multi-detector computed tomography (MDCT) scanning for interventional procedures can prove to be logistically challenging as resources are often in different areas...  相似文献   
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Abstract

Having ‘good’ doctors is important to everybody. How to select medical students better has been discussed repeatedly for more than seventy years, implying that prevailing methods could be improved. A significant body of research exists about selection methods and their application in medicine. Yet most medical schools world-wide continue to use prior academic performance and cognitive ability as their major criteria for selection, with minor or no consideration of personal qualities and interpersonal skills (possibly assuming they will develop naturally during training and practice). We describe the main methods available for assessing personal qualities of applicants to medical school and have attempted to identify some reasons and systemic disincentives working against their adoption.  相似文献   
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Mutations in C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis (ALS). Accumulating evidence implicates astrocytes as important non-cell autonomous contributors to ALS pathogenesis, although the potential deleterious effects of astrocytes on the function of motor neurons remains to be determined in a completely humanized model of C9orf72-mediated ALS. Here, we use a human iPSC-based model to study the cell autonomous and non-autonomous consequences of mutant C9orf72 expression by astrocytes. We show that mutant astrocytes both recapitulate key aspects of C9orf72-related ALS pathology and, upon co-culture, cause motor neurons to undergo a progressive loss of action potential output due to decreases in the magnitude of voltage-activated Na+ and K+ currents. Importantly, CRISPR/Cas-9 mediated excision of the C9orf72 repeat expansion reverses these phenotypes, confirming that the C9orf72 mutation is responsible for both cell-autonomous astrocyte pathology and non-cell autonomous motor neuron pathophysiology.  相似文献   
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The early presentation of childhood allergies and the rise in their prevalence suggest that changes in early‐life exposures may increase the predisposition. Very early‐life exposures may act upon the developing foetal immune system and include infection, environmental tobacco smoke, other pollutants and nutrients provided via the mother. Three nutrients have come under close scrutiny: vitamin D, omega 3 polyunsaturated fatty acids (PUFAs) and folate (or the synthetic form, folic acid). Much of the data on these nutrients are observational although some randomised, placebo‐controlled trials have been conducted with omega 3 PUFAs and one with vitamin D. Some studies with omega 3 PUFA supplements in pregnancy have demonstrated immunomodulatory effects on the neonate and a reduction in risk of early sensitisation to allergens. A few studies with omega 3 polyunsaturated fatty acid supplements in pregnancy have shown a reduction in proportion of children affected by allergic symptoms (food allergy) or in symptom severity (atopic dermatitis). Observational studies investigating the association of maternal vitamin D intake or maternal or neonatal vitamin D status have been inconsistent. One randomised, controlled trial of vitamin D supplementation during pregnancy did not show any significant effect on allergic outcome in the offspring. Studies investigating the association between maternal folic acid or folate intake or maternal or neonatal folate status and offspring risk of allergic disease have been equivocal. Further evidence is required to clarify whether increased intake of these nutrients during pregnancy influences allergic disease in the offspring. In the light of current evidence, mothers should not either increase or avoid consuming these nutrients to prevent or ameliorate allergic disease in their offspring. However, these essential nutrients each have important roles in foetal development. This is reflected in current government recommendations for intake of these nutrients by pregnant women.  相似文献   
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