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261篇 您的检索式:作者名="lvarez A"
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1Comparative review of vertebroplasty and kyphoplasty显示文摘The aim of this review is to compare the effectiveness of percutaneous vertebroplasty and kyphoplasty to treat pain and improve functional outcome from ver-tebral fractures secondary to osteoporosis and tumor conditions. In 2009, two open randomized controlled trials published in the New England Journal of Medicine questioned the value of vertebroplasty in treating ver-tebral compression fractures. Nevertheless, the prac-tice of physicians treating these conditions has barely changed. The objective of this review is to try to clarify the most important issues, based on our own experi-ence and the reported evidence about both techniques, and to guide towards the most appropriate choice of treatment of vertebral fractures, although many ques-tions still remain unanswered.Ferno Ruiz Santiago Alicia Santiago Chinchilla Luis Guzmán álvarez Antonio Luis Pérez Abela Maria del Mar Castellano García Miguel Pajares López 2014World Journal of Radiology2014,6,6:30
2Phylogenetic alpha and beta diversity in tropical tree assemblages along regionalscale environmental gradients in northwest South America显示文摘Aims Environmental gradients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying these relationships.A potentially powerful approach to studying diversity gradients is to quantify the phylogenetic structure within and between assemblages arrayed along broad spatial and environmental gradients.Here,we evaluate the phylogenetic structure of plant assemblages along an environmental gradient with the expectation that the habitat specialization of entire lineages is an important evolutionary pattern influencing the structure of tree communities along environmental gradients.Methods We evaluated the effect of several environmental variables on the phylogenetic structure of plant assemblages in 145 plots distributed in northwestern South America that cover a broad environmental gradient.The phylogenetic alpha diversity was quantified for each plot and the phylogenetic beta diversity between each pair of plots was also quantified.Both the alpha and beta diversity measures were then related to spatial and environmental gradients in the study system.Important Findings We found that gradients in temperature and potential evapotranspiration have a strong relationship with the phylogenetic alpha diversity in our study system,with phylogenetic overdispersion in low temperatures and phylogenetic clustering at higher temperatures.Further,the phylogenetic beta diversity between two plots increases with an increasing difference in temperature,whereas annual precipitation was not a significant predictor of community phylogenetic turnover.We also found that the phylogenetic structure of the plots in our study system was related to the degree of seasonal flooding and seasonality in precipitation.In particular,more stressful environments such as dry forests and flooded forests showed phylogenetic clustering.Finally,in contrast with previous studies,we find that phylogenetic beta diversity was not strongly related to the spatial distance separating two forest plots,which may be the result of the importance of the three independent mountain ranges in our study system,which generate a high degree of environmental variation over very short distances.In conclusion,we found that environmental gradients are important drivers of both phylogenetic alpha and phylogenetic beta diversities in these forests over spatial distance.Sebastián González-Caro María Natalia Umaña Esteban Álvarez Pablo R.Stevenson Nathan G.Swenson 2014Journal of Plant Ecology2014,7,2:17
3Pulmonary vein stenosis:Etiology,diagnosis and management显示文摘Pulmonary vein stenosis(PVS) is rare condition characterized by a challenging diagnosis and unfavorable prognosis at advance stages. At present, injury from radiofrequency ablation for atrial fibrillation has become the main cause of the disease. PVS is characterized by a progressive lumen size reduction of one or more pulmonary veins that, when hemodynamically significant, may raise lobar capillary pressure leading to signs and symptoms such as shortness of breath, cough, and hemoptysis. Image techniques(transesophageal echocardiography, computed tomography, magnetic resonance and perfusion imaging) are essential to reach a final diagnosis and decide an appropriate therapy. In this regard, series from referral centers have shown that surgical and transcatheter interventions may improve prognosis. The purpose of this article is to review the etiology, assessment and management of PVS.Pablo Pazos-López Cristina García-Rodríguez Alba Guitián-González Emilio Paredes-Galán María ángel De La Guarda álvarez-Moure Marta Rodríguez-álvarez José Antonio Baz-Alonso Elvis Teijeira-Fernández Francisco Eugenio Calvo-Iglesias Andrés íniguez-Romo 2016World Journal of Cardiology2016,8,1:6
4Reduced Exposure to Calcineurin Inhibitors Early After Liver Transplantation Prevents Recurrence of Hepatocellular Carcinoma显示文摘Manuel Rodríguez-Perálvarez Emmanuel Tsochatzis María Carmen Naveas Giulia Pieri Carmen García-Caparrós James O’Beirne Antonio Poyato-González Gustavo Ferrín-Sánchez Jose Luis Montero-álvarez David Patch Douglas Thorburn Javier Brice?o Manuel De la Mata A 2013Journal of Hepatology2013,,:5
5Recombinant streptokinase vs phenylephrine-based suppositories in acute hemorrhoids, randomized, controlled trial(THERESA-3)显示文摘AIM: To compare the efficacy and safety of recombinant streptokinase(rSK) and phenylephrine-based suppositories in acute hemorrhoidal disease.METHODS: A multicenter(14 sites), randomized(1:1), open, parallel groups, active controlled trial was done. After inclusion, subjects with acute symptoms of hemorrhoids, who gave their written, informed consent to participate, were centrally randomized to receive, as outpatients, rSK(200000 IU) or 0.25% phenylephrine suppositories, which had different organoleptic characteristics. Treatment was administered by the rectal route, one unit every 6 h during 48 h for rSK, and up to a maximum of 5 d(20 suppositories) for phenylephrine. Evaluations were performed at 3, 5 and 10 d postinclusion. The main end-point was the 5th-day complete clinical response(disappearance of pain and edema, and ≥ 70% reduction of the lesion size). Time to response and need for thrombectomy were secondary efficacy variables. Adverse events were evaluated too. RESULTS: 5thday complete response rates were 83/110(75.5%) and 36/110(32.7%) with rSK and phenylephrine suppositories, respectively. This 42.7% difference(95%CI: 30.5-54.2) was highly significant(P < 0.001). The advantage was detected since the early 3rdday evaluation(37.3% vs 6.4% for the rSK and active control groups, respectively; P < 0.001) and was kept even at the late 10thday assessment(83.6% vs 58.2% for rSK and phenylephrine, respectively; P < 0.001). Time for complete response was significantly shorter(P = 0.031; log-rank test) in the rSK group(median: 4.9 d; 95%CI: 4.8-5.0) with respect to the active control(median: 9.8 d; 95%CI: 9.8-10.0). Thrombectomy was necessary in 1/59 and 8/57 patients with baseline thrombosis in the rSK and phenylephrine groups, respectively(P = 0.016). There were no adverse events attributable to the experimental treatment. CONCLUSION: rSK suppositories showed a significant advantage over a widely used over-the-counter phen-ylephrine preparation for the treatment of acute hemorrhoidal illness, with an adequate safety profile.Francisco Hernández-Bernal Georgina Castellanos-Sierra Carmen M Valenzuela-Silva Karem M Catasús-lvarez Roselin Valle-Cabrera Ana Aguilera-Barreto Pedro A López-Saura 2014World Journal of Gastroenterology2014,20,6:4
6Coronary physiology assessment in the catheterization laboratory显示文摘Physicians cannot rely solely on the angiographic appearance of epicardial coronary artery stenosis when evaluating patients with myocardial ischemia. Instead, sound knowledge of coronary vascular physiology and of the methods currently available for its characterization can improve the diagnostic and prognostic accuracy of invasive assessment of the coronary circulation, and help improve clinical decision-making. In this article we summarize the current methods available for a thorough assessment of coronary physiology.Felipe Díez-delhoyo Enrique Gutiérrez-Ibanes Gerard Loughlin Ricardo Sanz-Ruiz María Eugenia Vázquez-álvarez Fernando Sarnago-Cebada Rocío Angulo-Llanos Ana Casado-Plasencia Jaime Elízaga Francisco Fernández Avilés Diáz 2015World Journal of Cardiology2015,7,9:2
7Liver fat deposition and mitochondrial dysfunction in morbid obesity:An approach combining metabolomics with liver imaging and histology显示文摘AIM: To explore the usefulness of magnetic resonance imaging(MRI) and spectroscopy(MRS) for assessment of non-alcoholic fat liver disease(NAFLD) as compared with liver histological and metabolomics findings. METHODS: Patients undergoing bariatric surgery following procedures involved in laparoscopic sleeve gastrectomy were recruited as a model of obesityinduced NAFLD in an observational, prospective, singlesite, cross-sectional study with a pre-set duration of 1 year. Relevant data were obtained prospectively and surrogates for inflammation, oxidative stress and lipid and glucose metabolism were obtained through standard laboratory measurements. To provide reliable data from MRI and MRS, novel procedures were designed to limit sampling variability and other sources of error using a 1.5T Signa HDx scanner and protocols acquired from the 3D or 2D Fat SAT FIESTA prescription manager. We used our previously described 1H NMRbased metabolomics assays. Data were obtained immediately before surgery and after a 12-mo period including histology of the liver and measurement of metabolites. Values from 1H NMR spectra obtained after surgery were omitted due to technical limitations.RESULTS: MRI data showed excellent correlation with the concentration of liver triglycerides, other hepatic lipid components and the histological assessment, w h i c h e xc l u d e d t h e p r e s e n c e o f n o n-a l c o h o l i c steatohepatitis(NASH). MRI was sufficient to follow up NAFLD in obese patients undergoing bariatric surgery and data suggest usefulness in other clinical situations. The information provided by MRS replicated that obtained by MRI using the-CH3 peak(0.9 ppm), the-CH2- peak(1.3 ppm, mostly triglyceride) and the-CH=CH- peak(2.2 ppm). No patient depicted NASH. After surgery all patients significantly decreased their body weight and steatosis was virtually absent even in patients with previous severe disease. Improvement was also observed in the serum concentrations of selected variables. The most relevant findings using metabolomics indicate increased levels of triglyceride and monounsaturated fatty acids in severe steatosis but those results were accompanied by a significant depletion of diglycerides, polyunsaturated fatty acids, glucose-6-phosphate and the ATP/AMP ratio. Combined data indicated the coordinated action on mitochondrial fat oxidation and glucose transport activity and may support the consideration of NAFLD as a likely mitochondrial disease. This concept may helpto explain the dissociation between excess lipid storage in adipose tissue and NAFLD and may direct the search for plasma biomarkers and novel therapeutic strategies. A limitation of our study is that data were obtained in a relatively low number of patients.CONCLUSION: MRI is sufficient to stage NAFLD in obese patients and to assess the improvement after bariatric surgery. Other data were superfluous for this purpose.Nahum Calvo Raúl Beltrán-Debón Esther Rodríguez-Gallego Anna Hernández-Aguilera Maria Guirro Roger Mariné-Casadó Lidón Millá Josep M Alegret Fàtima Sabench Daniel del Castillo María Vinaixa Miguelàngel Rodríguez Xavier Correig Roberto García-álvarez Javier A Menendez Jordi Camps Jorge Joven 2015World Journal of Gastroenterology2015,21,24:2
8Conservative management of perforated duodenal diverticulum: A case report and review of the literature显示文摘Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.David Martínez-Cecilia Alvaro Arjona Sánchez Manuel Gómez álvarez Eva Torres Tordera Antonio Luque Molina Victor Valentí Azcárate Javier Briceo Delgado Francisco Javier Padillo Pedro López-Cillero Sebastián Rufián Pea 2008World Journal of Gastroenterology2008,14,12:2
9Science Letters:Visual odometry for road vehicles—feasibility analysis显示文摘Estimating the global position of a road vehicle without using GPS is a challenge that many scientists look forward to solving in the near future. Normally, inertial and odometry sensors are used to complement GPS measures in an attempt to provide a means for maintaining vehicle odometry during GPS outage. Nonetheless, recent experiments have demonstrated that computer vision can also be used as a valuable source to provide what can be denoted as visual odometry. For this purpose, vehicle motion can be estimated using a non-linear, photogrametric approach based on RAndom SAmple Consensus (RANSAC). The results prove that the detection and selection of relevant feature points is a crucial factor in the global performance of the visual odometry algorithm. The key issues for further improvement are discussed in this letter.SOTELO Miguel-angel GARCíA Roberto PARRA Ignacio FERNNDEZ David GAVILN Miguel LVAREZ Sergio NARANJO José-eugenio 2007Journal of Zhejiang University-Science A(Applied Physics & Engineering)2007,8,12:2
10Sensory, physical, chemical and microbiological changes in aquacultured meagre ( Argyrosomus regius ) fillets during ice storage显示文摘M.D. Hernández M.B. López A. álvarez E. Ferrandini B. García García M.D. Garrido 2008Food Chemistry2008,,1:2
11Contribution of autoch- thonous maize populations for adaptation to European con- ditions显示文摘Revilla P Boyat A lvarez A 2006Euphytica2006,152,2:1
12Measurement and simulation of climate inside Almería-type greenhouses using computational fluid dynamics显示文摘Molina-Aiz F D Valera D L álvarez A J 2004Agricultural and Forest Meteorology2004,125,:1
13A reactivity study of chars obtained at different temperatures in relation to theirpetrographic characteristics 显示文摘Alonso M J G Borrego A G álvarez D 2001Fuel Processing Technology2001,,69:1
14Sensory, physical, chemical and microbiological changes in aquacultured meagre ( Argyrosomus regius ) fillets during ice storage显示文摘M.D. Hernández M.B. López A. álvarez E. Ferrandini B. García García M.D. Garrido 2008Food Chemistry2008,,1:1
15Repetitive control of tubular heat exchangers显示文摘A′LVAREZ J D YEBRA L J BERENGUEL M 2007Journal of Process Control2007,17,9:1
16Microstructural characterization of material adhered over cutting tool in the dry machining of aerospace aluminum alloys 显示文摘Sanchez J M Rubio E lvarez M A 2005Journal of Materials Processing Technology2005,,:1
17A study of oxy-coal combustion with steam addition and biomass blending by thermogravimetric analysis显示文摘Gil M V Riaza J (A)lvarez L 0,,01:1
18Recovery of phenol from aqueous solutions using hollow fibre contactors显示文摘GONZALEZ M M J LUQUE S LVAREZ J R A 2003Membr Sci2003,213,:1
19Characterization of molecular mass ranges of two coal tar distillate fractions (creosote and anthracene oils) and aromatic standards by LD - MS, GC - MS, probe-MS and size - exclusion chromatography显示文摘MORGAN T J GEORGE A LVAREZ P A 2008Energy Fuels2008,22,5:1
20E- valuation of the Enzyme Manganese Peroxidase in an Industrial Se- quence for the Lignin Oxidation and Bleaching of Eucalyptus Kraft Pulp 显示文摘Feijoo Gumersindo Moreira Mar'a Teresa Pablo A' lvarez 2008Journal of Applied Polymer Science2008,109,:1
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