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1.
José Roberto Jurado Jorge Hernán Santos Nieto Jairo Ospina Gaitán Constanza Garzón Bonilla Ricardo Villarreal David Acevedo Laura Cabrera Luis Felipe Cabrera Mauricio Pedraza 《Arab Journal Of Gastroenterology》2021,22(2):170-173
Background and study aimsThe COVID-19 outbreak has reorganized surgical team conditions regarding endoscopy. The number of interventions has been reduced, the number of healthcare professionals must be limited, and both the patients and physicians are more protected than ever.Patients and MethodsIn the highest peak of contagion in Colombia, endoscopy, colonoscopy, and esophagogastroduodenoscopy were performed using a low-cost disposable device. A total of 1388 procedures were performed. Every patient was assessed for symptoms via a telephone call, at the health center, and after the procedure, following specific attention routes.ResultsAfter procedure follow-up, no positive cases of COVID-19 were noted.ConclusionThe methodology reduced the risk of infection during the COVID-19 pandemic. 相似文献
2.
Risk Factors and Effect of Acute Kidney Injury on Outcomes Following Total Hip and Knee Arthroplasty
Michael Yayac Zachary S. Aman Alexander J. Rondon Timothy L. Tan P. Maxwell Courtney James J. Purtill 《The Journal of arthroplasty》2021,36(1):331-338
BackgroundDevelopment of acute kidney injury (AKI) following primary total joint arthroplasty (TJA) is a potentially avoidable complication associated with negative outcomes including discharge to facilities and mortality. Few studies have identified modifiable risk factors or strategies that the surgeon may use to reduce this risk.MethodsWe identified all patients undergoing primary TJA at a single hospital from 2005 to 2017, and collected patient demographics, comorbidities, short-term outcomes, as well as perioperative laboratory results. We defined AKI as an increase in creatinine levels by 50% or 0.3 points. We compared demographics, comorbidities, and outcomes between patients who developed AKI and those who did not. Multivariate regressions identified the independent effect of AKI on outcomes. A stochastic gradient boosting model was constructed to predict AKI.ResultsIn total, 814 (3.9%) of 20,800 patients developed AKI. AKI independently increased length of stay by 0.26 days (95% confidence interval [CI] 0.14-0.38, P < .001), in-hospital complication risk (odds ratio = 1.73, 95% CI 1.45-2.07, P < .001), and discharge to facility risk (odds ratio = 1.26, 95% CI 1.05-1.53, P = .012). Forty-one predictive variables were included in the predictive model, with important potentially modifiable variables including body mass index, perioperative hemoglobin levels, surgery duration, and operative fluids administered. The final predictive model demonstrated excellent performance with a c-statistic of 0.967.ConclusionOur results confirm that AKI has adverse effects on outcome metrics including length of stay, discharge, and complications. Although many risk factors are nonmodifiable, maintaining adequate renal perfusion through optimizing preoperative hemoglobin, sufficient fluid resuscitation, and reducing blood loss, such as through the use of tranexamic acid, may aid in mitigating this risk. 相似文献
3.
The mycophenolic acid (MPA) preparations are one of the most commonly used immunosuppressants in the United States. However, these agents carry a black box warning regarding their use during pregnancy due to an association with increased risk of miscarriage and congenital defects. To ensure that the benefits of MPA outweigh the risks, the Food and Drug Administration (FDA) required all manufacturers of MPA products to propose risk evaluation and mitigation strategies (REMS). Four years after initially calling for proposals, the FDA approved a single shared REMS system in September 2012. The elements of the MPA REMS include a medication guide and elements to assure safe use (ETASU). The medication guide, which was previously FDA‐approved in 2008, should continue to be distributed to patients, and the ETASU requires physicians to complete training and obtain patient signatures on the “Patient‐Prescriber Acknowledgement Form.” A single, national, voluntary pregnancy registry is available, and pregnant patients should be encouraged to participate. Although the impact of the MPA REMS on clinical practice is not clear, it is a step toward increasing the understanding of fetal risks with MPA products among patients and possibly practitioners. 相似文献
4.
Nico Bauer Robert J. Brecha Gunnar Luderer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(42):16805-16810
The events of March 2011 at the nuclear power complex in Fukushima, Japan, raised questions about the safe operation of nuclear power plants, with early retirement of existing nuclear power plants being debated in the policy arena and considered by regulators. Also, the future of building new nuclear power plants is highly uncertain. Should nuclear power policies become more restrictive, one potential option for climate change mitigation will be less available. However, a systematic analysis of nuclear power policies, including early retirement, has been missing in the climate change mitigation literature. We apply an energy economy model framework to derive scenarios and analyze the interactions and tradeoffs between these two policy fields. Our results indicate that early retirement of nuclear power plants leads to discounted cumulative global GDP losses of 0.07% by 2020. If, in addition, new nuclear investments are excluded, total losses will double. The effect of climate policies imposed by an intertemporal carbon budget on incremental costs of policies restricting nuclear power use is small. However, climate policies have much larger impacts than policies restricting the use of nuclear power. The carbon budget leads to cumulative discounted near term reductions of global GDP of 0.64% until 2020. Intertemporal flexibility of the carbon budget approach enables higher near-term emissions as a result of increased power generation from natural gas to fill the emerging gap in electricity supply, while still remaining within the overall carbon budget. Demand reductions and efficiency improvements are the second major response strategy. 相似文献
5.
目的:借鉴美国药品风险评估与减轻策略,为我国探索建立良好的药品风险控制体系提供参考。方法:概述美国药品风险评估与减轻策略,分析风险评估与减轻策略的实施现状,学习其实践经验REMS药房门户网站,为我国相应机制的建立提供借鉴。结果与结论:美国药品风险评估与减轻策略的实践始终坚持“保证药品效益大于风险”的原则,将患者使用药品的风险降至最小化,提高药品信息的透明度,减少和预防药品上市后不良反应事件的发生和危害,完善对药品的全生命周期监管。我国可以借鉴美国经验,立足中国医疗卫生体制现状,探索建立符合发展要求的医疗联动网络。 相似文献
6.
Sharifah B. Alhadad Ivan C.C. Low Jason K.W. Lee 《Journal of Science and Medicine in Sport》2021,24(1):105-109
ObjectivesWe investigated the thermoregulatory responses to ice slurry ingestion during low- and moderate-intensity exercises with restrictive heat loss.DesignRandomised, counterbalanced, cross-over design.MethodsFollowing a familiarisation trial, ten physically active males exercised on a motorised treadmill at low-intensity (L; 40% VO2max) or moderate-intensity (M; 70% VO2max) for 75-min, in four randomised, counterbalanced trials. Throughout the exercise bout, participants donned a raincoat to restrict heat loss. Participants ingested 2 g kg?1 body mass of ambient water (L + AMB and M + AMB trials) or ice slurry (L + ICE and M + ICE trials) at 15-min intervals during exercise in environmental conditions of Tdb, 25.1 ± 0.6 °C and RH, 63 ± 5%. Heart rate (HR), gastrointestinal temperature (Tgi), mean weighted skin temperature (Tsk), estimated sweat loss, ratings of perceived exertion (RPE) and thermal sensation (RTS) were recorded.ResultsCompared to L + AMB, participants completed L + ICE trials with lower ΔTgi (0.8 ± 0.3°C vs 0.6 ± 0.2 °C; p = 0.03), mean RPE (10 ± 1 vs 9 ± 1; p = 0.03) and estimated sweat loss (0.91 ± 0.2 L vs 0.78 ± 0.27 L; p = 0.04). Contrastingly, Tgi (p = 0.22), Tsk (p = 0.37), HR (p = 0.31), RPE (p = 0.38) and sweat loss (p = 0.17) were similar between M + AMB and M + ICE trials. RTS was similar during both low-intensity (4.9 ± 0.5 vs 4.7 ± 0.3; p = 0.10) and moderate-intensity exercise (5.3 ± 0.47 vs 5.0 ± 0.4; p = 0.09).ConclusionsPer-cooling using ice slurry ingestion marginally reduced thermal strain during low-intensity but not during moderate-intensity exercise. Ice slurry may be an effective and practical heat mitigation strategy during low-intensity exercise such as in occupational and military settings, but a greater volume should be considered to ensure its efficacy. 相似文献
7.
8.
Ben P. Werling Timothy L. Dickson Rufus Isaacs Hannah Gaines Claudio Gratton Katherine L. Gross Heidi Liere Carolyn M. Malmstrom Timothy D. Meehan Leilei Ruan Bruce A. Robertson G. Philip Robertson Thomas M. Schmidt Abbie C. Schrotenboer Tracy K. Teal Julianna K. Wilson Douglas A. Landis 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(4):1652-1657
Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands—farmland suboptimal for food crops—could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks—primarily annual grain crops—on marginal lands have been questioned. Here we show that perennial bioenergy crops provide an alternative to annual grains that increases biodiversity of multiple taxa and sustain a variety of ecosystem functions, promoting the creation of multifunctional agricultural landscapes. We found that switchgrass and prairie plantings harbored significantly greater plant, methanotrophic bacteria, arthropod, and bird diversity than maize. Although biomass production was greater in maize, all other ecosystem services, including methane consumption, pest suppression, pollination, and conservation of grassland birds, were higher in perennial grasslands. Moreover, we found that the linkage between biodiversity and ecosystem services is dependent not only on the choice of bioenergy crop but also on its location relative to other habitats, with local landscape context as important as crop choice in determining provision of some services. Our study suggests that bioenergy policy that supports coordinated land use can diversify agricultural landscapes and sustain multiple critical ecosystem services.In agricultural landscapes, balancing the provisioning of food and energy with maintenance of biodiversity and ecosystem functions is a global challenge. To avoid impacts on food production, attention is increasingly being focused on the potential for marginal lands to support bioenergy production (1). Marginal lands, those suboptimal for food production, may consist of relatively small areas within generally productive landscapes or larger regions where conditions generally limit crop productivity. However, there is increasing recognition that these lands are already performing a variety of useful functions, and their conversion to bioenergy cropping could reduce these services. For example, in the north central United States, rising commodity prices are predicted to bring marginal croplands—including Conservation Reserve Program lands—into annual crop production with negative impacts on wildlife habitat and water quality (2, 3). With 2013 corn plantings at recent record highs (4) and new reports of grassland and wetland conversion to cropland (5, 6), this may be occurring already.An alternative to annual cropping is conversion of marginal croplands to perennial, cellulosic crops for bioenergy. Although current US biofuel production centers on grain ethanol derived from annual monocultures of maize (Zea mays), this situation could change with full implementation of the 2007 US Energy Independence and Security Act (7), which calls for increased production of cellulosic biofuels. In the Midwest United States, perennial grasses and forbs grown on marginal lands could provide up to 25% of national targets for cellulosic biofuel, with substantial greenhouse gas (GHG) benefits (8). Moreover, increasing the area of perennial cover on the landscape is predicted to positively affect a diverse array of organisms and ecological functions (9–11), leading to important synergies that have not yet informed the ongoing bioenergy debate. Here we provide the most comprehensive empirical evaluation of this hypothesis to date, reporting data that elucidate the impacts of different bioenergy cropping systems on a wide variety of organisms and the ecosystem functions they perform.Previous studies have examined the ability of select bioenergy crops to support specific taxa (12) or individual services such as energy production (13) or GHG mitigation (14), without consideration of the tradeoffs or synergies that can arise when considering entire suites of organisms and ecosystem functions. We report on a unique multidisciplinary study of matched sets of organisms and ecosystem services and show that perennial grass energy crops (switchgrass, Panicum virgatum, and mixed prairie plantings) synergistically enhance diversity of a variety of organisms and levels of the services they provide. We further quantify the importance of landscape context on service provisioning, suggesting that policy supporting intentional design of bioenergy landscapes could increase sustainability of both food and energy production. 相似文献
9.
Chown SL Huiskes AH Gremmen NJ Lee JE Terauds A Crosbie K Frenot Y Hughes KA Imura S Kiefer K Lebouvier M Raymond B Tsujimoto M Ware C Van de Vijver B Bergstrom DM 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(13):4938-4943
Invasive alien species are among the primary causes of biodiversity change globally, with the risks thereof broadly understood for most regions of the world. They are similarly thought to be among the most significant conservation threats to Antarctica, especially as climate change proceeds in the region. However, no comprehensive, continent-wide evaluation of the risks to Antarctica posed by such species has been undertaken. Here we do so by sampling, identifying, and mapping the vascular plant propagules carried by all categories of visitors to Antarctica during the International Polar Year''s first season (2007–2008) and assessing propagule establishment likelihood based on their identity and origins and on spatial variation in Antarctica''s climate. For an evaluation of the situation in 2100, we use modeled climates based on the Intergovernmental Panel on Climate Change''s Special Report on Emissions Scenarios Scenario A1B [Nakićenović N, Swart R, eds (2000) Special Report on Emissions Scenarios: A Special Report of Working Group III of the Intergovernmental Panel on Climate Change (Cambridge University Press, Cambridge, UK)]. Visitors carrying seeds average 9.5 seeds per person, although as vectors, scientists carry greater propagule loads than tourists. Annual tourist numbers (∼33,054) are higher than those of scientists (∼7,085), thus tempering these differences in propagule load. Alien species establishment is currently most likely for the Western Antarctic Peninsula. Recent founder populations of several alien species in this area corroborate these findings. With climate change, risks will grow in the Antarctic Peninsula, Ross Sea, and East Antarctic coastal regions. Our evidence-based assessment demonstrates which parts of Antarctica are at growing risk from alien species that may become invasive and provides the means to mitigate this threat now and into the future as the continent''s climate changes. 相似文献
10.
Esperanza Menndez Miguel ngel Sanjun Ricardo García-Roves Cristina Argiz Hairon Recino 《Materials》2021,14(11)
Featured Application In this paper, blended cements are proposed as an effective means of meeting the needs of mitigating climatic change. This proposal is a two-pronged strategy, i.e., durable and sustainable. The pozzolanic reaction of four binders is assessed, which is related to an alkali–silica reaction (ASR). Thanks to the findings made here, mix-design optimization can be performed. AbstractAlkali–silica reaction (ASR) is a swelling reaction that occurs in concrete structures over time between the reactive amorphous siliceous aggregate particles and the hydroxyl ions of the hardened concrete pore solution. The aim of this paper is to assess the effect of pozzolanic Portland cements on the alkali–silica reaction (ASR) evaluated from two different points of view: (i) alkali-silica reaction (ASR) abatement and (ii) climatic change mitigation by clinker reduction, i.e., by depleting its emissions. Open porosity, SEM microscopy, compressive strength and ASR-expansion measurements were performed in mortars made with silica fume, siliceous coal fly ash, natural pozzolan and blast-furnace slag. The main contributions are as follows: (i) the higher the content of reactive silica in the pozzolanic material, the greater the ASR inhibition level; (ii) silica fume and coal fly ash are the best Portland cement constituents for ASR mitigation. 相似文献