3,089 research outputs found
Operative management of lumbar disc herniation : the evolution of knowledge and surgical techniques in the last century.
No full textRemoval of a herniated disc with the use of the operative microscope was first performed by Yasargil (Adv Neurosurg. 4:81-2, 1977) in 1977. However, it began to be used more and more only in the late 1980s (McCulloch JA (1989) Principles of microsurgery for lumbar disc disease. Raven Press, New York). In the 1990s, many spinal surgeons abandoned conventional discectomy with naked-eye to pass to the routine practice of microdiscectomy. The merits of this technique are that it allows every type of disc herniation to be excised through a short approach to skin, fascia and muscles as well as a limited laminoarthrectomy. For these reasons, it has been, and still is, considered the "gold standard" of surgical treatment for lumbar disc herniation, and the method used by the vast majority of spinal surgeons. In the 1990s, the advent of MRI and the progressive increase in definition of this modality of imaging, as well as histopathologic and immunochemical studies of disc tissue and the analysis of the results of conservative treatments have considerably contributed to the knowledge of the natural evolution of a herniated disc. It was shown that disc herniation may decrease in size or disappear in a few weeks or months. Since the second half of the 1990s there has been a revival of percutaneous procedures. Some of these are similar to the percutaneous automated nucleotomy; other methods are represented by intradiscal injection of a mixture of "oxygen-ozone" (Alexandre A, Buric J, Paradiso R. et al. (2001) Intradiscal injection of oxygen ozone for the treatment of lumbar disc herniations: result at 5 years. 12th World Congress of Neurosurgery; 284-7), or laserdiscectomy performed under CT scan (Menchetti PPM. (2006) Laser Med Sci. 4:25-7). The really emerging procedure is that using an endoscope inserted into the disc through the intervertebral foramen to visualize the herniation and remove it manually using thin pituitary rongeurs, a radiofrequency probe or both (Chiu JC. (2004) Surg Technol Int. 13:276-86). Microdiscectomy is still the standard method of treatment due to its simplicity, low rate of complications and high percentage of satisfactory results, which exceed 90% in the largest series. Endoscopic transforaminal discectomy appears to be a reliable method, able to give similar results to microdiscectomy, provided the surgeon is expert enough in the technique, which implies a long learning curve in order to perform the operation effectively, with no complications. All the non-endoscopic percutaneous procedures now available can be used, but the patient must be clearly informed that while the procedure is simple and rapid, at least for the disc L4-L5 and those above (except for laserdiscectomy under CT, that can be easily performed also at L5-S1), their success rate ranges from 60 to 70% and that, in many cases, pain may decrease slowly and may take even several weeks to disappear. © 2011 Springer-Verlag/Wien
“Era por Alexandre tod’esto demostrado”: ¿pruebas verídicas y pruebas engañosas en el Libro de Alexandre?
No full textEl Libro de Alexandre es un texto de s. XIII, que se escribió en la España medieval. En este escrito, el autor pretende demostrar que, en el Alexandre, algunas de las situaciones que se ponen a prueba son aceptadas, pero eso no significa que el macedonio gane la prueba. El articulo esta dividido en tres apartados. En el primero, el autor da cuenta de la historia textual de la obra y también dedica ciertas líneas al Estado de la cuestión del texto; mientras que, en la segunda parte, nos guía a conceptos etimológicos de los términos prueba, evidencia y demás. En el tercer apartado se centra en algunas pruebas expuestas en el Libro de Alexandre.The Libro de Alexandre is a literary work, written during the medieval Spain. In this paper, the author tries to demonstrate that, carefully reading the L.A, some of the situations that are set as proves are accepted, but it does not mean that Alexander can be a victor. This paper is divided in three sections: firstly, the author tells the textual history of the L.A and, then, tries to update the State of art: on the other hand, in the second part, the author offers meanings about terms as: prueba and evidencia. Finally, the author focuses on certain passages contained in the Libro de Alexandre that can be taken as failed proves
Influence of Periodontal Status and Periodontopathogens on Levels of Oral Human β‐Defensin‐2 in Saliva
No full textMade available in DSpace on 2019-09-12T16:56:58Z (GMT). No. of bitstreams: 0
Previous issue date: 2013Background: Expression patterns of human beta-defensin-2 (HBD-2) mRNA or HBD-2 protein concentration and periodontal diseases have been a focus of scientific research. This study compares the salivary levels of HBD-2 protein concentration of healthy patients and patients with gingivitis and chronic periodontitis (CP) and correlates these levels with the presence of periodontopathogens. Methods: A total of 89 patients were enrolled in this study: 31 periodontally healthy, 27 with gingivitis, and 31 with CP. Plaque and gingival indices, probing depth, and clinical attachment level were measured. The presence of Campylobacter rectus, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Prevotella intermedia was evaluated qualitatively by conventional polymerase chain reaction. HBD-2 quantification in saliva was performed using an immune enzymatic assay. Frequency of periodontopathogens and HBD-2 protein concentration was assessed. Association between HBD-2 protein concentration (>= 100 pg/mL) and the simultaneous presence of one to two, three to four, or five to six periodontopathogens was tested. Results: Although periodontally healthy individuals and patients with gingivitis showed similar HBD-2 levels, the CP group displayed an increased level of HBD-2. P. gingivalis, P. intermedia, T. forsythia, and T. denticola were more prevalent in CP; however, their mere presence was not related to the increased levels of HBD-2 (Pearson correlation and multinomial logistic regression model). Conclusions: Salivary HBD-2 protein concentration was higher in patients with CP compared with healthy individuals or patients with gingivitis. These different protein concentrations were not related to the frequency of periodontopathogens. Clinical inflammatory profile had a higher impact on salivary HBD-2 levels than bacteria.[Pereira, Alexandre L.; Franco, Gilson C.; Cortelli, Sheila C.; Aquino, Davi R.; Raslan, Suzane A.; Cortelli, Jose R.] Universidade de Taubaté (Unitau), Dept Periodontol, Sao Paulo, Brazil[Costa, Fernando O.] Univ Fed Minas Gerais, Dept Periodontol, Belo Horizonte, MG, Brazi
Rewarding Innovation: Improving Federal Tax Support for Business R&D in Canada
No full textBusiness innovation is viewed by many as a solution to Canada’s ailing productivity performance. One of the more troubling aspects of Canada’s innovation track record is that businesses spend relatively little on research and development (R&D) despite having access to some of the world’s most generous R&D tax incentives. Canada’s low levels of business R&D have called into question the effectiveness of Canada’s generous R&D tax incentives, particularly the flagship federal Scientific Research and Experimental Development (SR&ED) program. A deeper analysis, however, reveals that tax incentives are effective in stimulating more R&D – that is, Canada would have lower levels of business R&D in the absence of these inducements. Instead, the root cause of Canada’s business R&D deficit appears to stem from structural aspects of the economy and, more importantly, a lack of demand-related pressure to pursue innovation.Fiscal and Tax Competitiveness, Canada, research and development (R&D) incentives, Scientific Research and Experimental Development (SR&ED) program
Energy and spin polarization analysis of near band gap photoemission in AlGaAs/GaAs heterostructures
No full textdiffuStats: an R package to compute diffusion-based scores on biological networks
No full textThis is a pre-copyedited, author-produced version of an article accepted for publication in Bioinformatics following peer review. The version of record Sergio Picart-Armada, Wesley K Thompson, Alfonso Buil, Alexandre Perera-Lluna; diffuStats: an R package to compute diffusion-based scores on biological networks, Bioinformatics, Volume 34, Issue 3, 1 February 2018, Pages 533–534 is available online at: https://doi.org/10.1093/bioinformatics/btx632.Label propagation and diffusion over biological networks are a common mathematical formalism in computational biology for giving context to molecular entities and prioritising novel candidates in the area of study.
There are several choices in conceiving the diffusion process -involving the graph kernel, the score definitions and the presence of a posterior statistical normalisation- which have an impact on the results.
This manuscript describes diffuStats, an R package that provides a collection of graph kernels and diffusion scores, as well as a parallel permutation analysis for the normalised scores, that eases the computation of the scores and their benchmarking for an optimal choice.Peer ReviewedPostprint (author's final draft
Characterization of multiple antilisterial peptides produced by sakacin P-producing Lactobacillus sakei subsp. sakei 2a.
No full textAntimicrobial compounds produced by lactic acid bacteria can be explored as natural food biopreservatives. In a previous report, the main antimicrobial compounds produced by the Brazilian meat isolate Lactobacillus sakei subsp. sakei 2a, i.e., bacteriocin sakacin P and two ribosomal peptides (P2 and P3) active against Listeria monocytogenes, were described. In this study, we report the spectrum of activity, molecular mass, structural identity and mechanism of action of additional six antilisterial peptides produced by Lb. sakei 2a, detected in a 24 h-culture in MRS broth submitted to acid treatment (pH 1.5) and proper fractionation and purification steps for obtention of free and cell-bound proteins. The six peptides presented similarity to different ribosomal proteins of Lb. sakei subsp sakei 23K and the molecular masses varied from 4.6 to 11.0 kDa. All peptides were capable to increase the efflux of ATP and decrease the membrane potential in Listeria monocytogenes. The activity of a pool of the obtained antilisterial compounds [enriched active fraction (EAF)] against Listeria monocytogenes in a food model (meat gravy) during refrigerated storage (4 °C) for 10 days was also tested and results indicated that the populations of L. monocytogenes in the food model containing the acid extract remained lower than those at time 0-day, evidencing that the acid extract of a culture of Lb. sakei 2a is a good technological alternative for the control of growth of L. monocytogenes in foods.Fil: Gianni de Carvalho, Katia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Bambirra, Felipe H. S.. Universidade Federal de Minas Gerais; BrasilFil: Nicoli, Jacques R.. Universidade Federal de Minas Gerais; BrasilFil: Oliveira, Jamil S.. Universidade Federal de Minas Gerais; BrasilFil: Santos, Alexandre M. C.. Universidade Federal de Minas Gerais; Brasil. Universidade Federal do Espírito Santo; BrasilFil: Bemquerer, Marcelo P.. Ministerio da Agricultura Pecuaria e Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; BrasilFil: Miranda, Antonio. Universidade Federal de Sao Paulo;Fil: Franco, Bernadette D. G. M.. Universidade de Sao Paulo; Brasi
GYM-Author: Generation Of Self-Learning Exercises In Philosophy
No full textCan a system have the ability to dynamically generate, on demand, a large number of adequate exercises in order to feed a learning environment in philosophy? We addressed this issue with our Philosophical Gymnasium (Phi-GYM) project with its authoring tool. Our motivation in designing the authoring tool was to: (1) Find an effective way to provide a wide range of exercises, and to; (2) Provide Philosophy teachers with an easy, autonomous, and collaborative way to create exercises related to classical Philosophical texts without worrying about technology. After a brief review of
related work, this article describes the design and development of the Philosophical Gymnasium’s web-based authoring system 2 , which semi-automatically generates self-learning exercises in the philosophical domain for a web-based learning environment (the Gymnasium’s second component). We conclude by presenting our plan about GYM-Author’s performance evaluation and deployment plan for scaling the system
Author(s) First Name Middle Name Surname Role Frederico B. A. Alexandre Third Author Affiliation
No full textThis page is for indexing purposes and will not be printed in the conference proceedings book. The text area is 29 × 45 picas (~12.3 cm × 19 cm) to fit in the printed proceedings book without reduction. When printed on letter paper there will be wide margins. Author(s
Opening the Door to Philosophy for teachers with GYM-Author
No full textCan a system have the ability to dynamically generate, on demand, a large number of self-learning and self-assessment exercises in order to supplement a learning environment in philosophy? We addressed this issue with our Phi-GYM project with its integrated authoring tool for tutoring systems in
philosophy. Our motivation in designing the authoring tool was to: (1) Find an effective way to semi-automatically generate a wide range of exercises, and; (2) Provide philosophy teachers with an easy, autonomous, and collective way to create exercises related to classical philosophical texts without worrying about any technology
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