465 resultados para 1381
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Introdução: A produção e o uso da literatura científica são analisados, quantificados e interpretados pela bibliometria, ciência utilizada para estudos métricos da informação publicada e que estuda as questões relacionadas com a comunicação científica e a atividade científica. Objetivo: O estudo apresentado é uma análise bibliométrica da produção científica portuguesa da área da saúde indexada na Web of Science. Métodos: Analisa-se a produção referente ao período entre 1992 e final de 2011. A análise da produção científica centrou-se nas seguintes variáveis: categorias de classificação da Web of Science, tipologia de documentos indexados, títulos de revistas, distribuição por anos de publicação, afiliação institucional, idiomas, países de origem dos autores com quem foram estabelecidas relações de parceria científica e quem facultou os financiamentos à investigação científica. Resultados: Foram contabilizados 34.208 trabalhos. Destes, o artigo é a forma mais utilizada pelos autores portugueses para a divulgação dos resultados de investigação (58,5%). A década mais recente é contemplada com 75,4% dos registos. A maioria da produção com visibilidade internacional é oriunda de universidades e de centros de investigação hospitalar; institutos, laboratórios da indústria farmacêutica e universidades estrangeiras têm valores residuais. A colaboração com outros investigadores internacionais destaca-se no caso da Europa (73,2%). O financiamento da investigação científica é suportado basicamente pela Fundação para a Ciência e Tecnologia (59,5%), seguida da Comissão Europeia (17,8%). O inglês é o idioma mais usado para a divulgação dos resultados de investigação nacional na área da saúde (97,8%). Conclusões: O uso de bases de dados ou de plataformas científicas para estudos bibliométricos é um processo moroso e difícil. O total de trabalhos em análise foi sempre o mesmo mas, em algumas variáveis, os valores não coincidem, quer porque alguns dos registos foram classificados em mais do que uma categoria temática, quer pelos trabalhos multidisciplinares oriundos das mesmas instituições, quer pelos trabalhos de colaboração internacional. Também no presente estudo os artigos são o veículo privilegiado para a divulgação dos resultados científicos. Apontamento final: deve encorajar-se a utilização de outras plataformas científicas e de outras bases de dados para uma mais completa recuperação da produção científica nacional na área da saúde. Introduction: The production and the use of the scientific literature are analyzed, quantified and interpreted by bibliometry. Bibliometry is the science used in published information metric studies and studies the questions of scientific communication and the scientific production. Aim of the study: This study presents a bibliometric analysis of the indexed Web of Science Portuguese scientific production in the health field. Methods: We analyzed the production from 1992 to the end of 2011. This analysis focused in several variables: general categories areas of Web of Science, indexed document types, source titles, publication years, group/corporate authors, languages, identification of the countries with scientific partnerships and identification of the funding agencies for scientific research. Results: We found 34.208 works. From this, the article is the most common channel for disseminating the research results (58.5%). The most recent decade has 75.4% of the total of records. Most of the production with international visibility becomes from universities and hospital research centers; institutes, pharmaceutical labs or foreign universities have residual values. Collaborating with other international researchers is very common, particularly with Europe (73.2%). In general, the Fundação para a Ciência e Tecnologia supports the scientific research (59.5%), followed by the European Commission (17.8%). The language commonly used for disseminating the research results in health is the English (97.8%). Conclusions: Using databases or scientific platforms for bibliometric studies is a hard and difficult process. The total of works analyzed was always the same but, with some variables, the numbers does not coincide: a) some of the registries were classified in several categories; b) some of the multidisciplinary works were from the same institution; c) the large number of international partnership. In this study, articles are the privileged way for disseminating the scientific results. A last thought: the use of other scientific platforms and databases should be encouraged for a more complete retrieval of the national research production in health.
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Introdução: Para além da importância já reconhecida da dispensa de medicação em dose unitária, a utilização de sistemas semiautomáticos no auxílio aos Serviços Farmacêuticos, quer do Kardex®, que será alvo de análise ao longo do trabalho, quer o Fast Dispensing System (FDS®), permite maior rapidez e segurança na preparação da Distribuição Individual Diária (DID) e Distribuição Individual Diária em Dose Unitária (DIDDU), auxiliando no envio do medicamento correto, na quantidade e qualidades certas, para cumprimento da prescrição médica proposta. O Kardex tem - se mostrado cada vez mais uma ferramenta de trabalho indispensável no dia – a - dia de um hospital com as características do Centro Hospitalar de São João, EPE pelo que se torna importante uma análise aos valores de utilização do Kardex. Assim sendo, este trabalho pretende dar a conhecer através de apresentações gráficas a realidade de utilização do Kardex® por Serviço Clínico, na preparação de medicação por dose unitária. Material e Métodos: Efetuou - se um estudo transversal, de carácter observacional, descritivo simples, tendo sido analisados a totalidade dos Serviços Clínicos reparados em Kardex®, entre 2 de Janeiro e 1 de Fevereiro, num total de 31 dias. Para tal efectuou - se a recolha de dados fornecida pelo Kardex®, sendo estes inseridos numa folha de Microsoft Office Excel®, e tratados posteriormente até obtenção de gráficos. Resultados: Os resultados obtidos mostram que sexta-feira e sábado são os dias em que o Kardex® tem mais tempo de utilização, mantendo-se os restantes dias da semana com valores de utilização bastante próximos. Quando analisados por Serviços Clínicos os dados mostram que são os Internamentos de Medicina A e B que ocupam respetivamente o primeiro e segundo lugar no que diz respeito ao maior tempo de utilização do Kardex®, com um tempo de trabalho em Kardex de aproximadamente 1 hora. Discussão / Conclusões: Sexta-feira e Sábado são os dias em que a utilização do Kardex® se torna maior devido à necessidade de preparação de medicação para 48h, ao contrário dos restantes dias em que a preparação da medicação é para apenas 24h. Os Internamentos de Medicina A e B são os Serviços Clínicos que mais tempo ocupam o Kardex®, muito devido ao grande número de camas que cada serviço tem, mas também às características dos doentes nele internados, a sua maioria bastante polimedicados.
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Aspergillus is among a growing list of allergens that aggravate asthmatic responses. Significant pulmonary pathology is associated with Aspergillus-induced allergic and asthmatic lung disease. Environments with high levels of exposure to fungi are found in animal production facilities such as for swine and poultry, and farmers working with these are at increased risk for occupational respiratory diseases. Seven Portuguese poultry and seven swine farms were analyzed in order to estimate the prevalence, amount, and distribution of Aspergillus species, as well as to determine the presence of clinical symptoms associated with asthma and other allergy diseases in these highly contaminated settings. From the collected fungal isolates (699), an average incidence of 22% Aspergillus was detected in poultry farms, while the prevalence at swine farms was 14%. The most frequently isolated Aspergillus species were A. versicolor, A. flavus, and A. fumigatus. In poultry farms, A. flavus presented the highest level of airborne spores (>2000 CFU/m3), whereas in swine farms the highest was A. versicolor, with an incidence fourfold greater higher than the other mentioned species. Eighty workers in these settings were analyzed, ranging in age from 17 to 93 yr. The potentially hazardous exposure of poultry workers to mold allergens using sensitization markers was evaluated. Although no significant positive association was found between fungal contamination and sensitization to fungal antigens, a high incidence of respiratory symptoms in professionals without asthma was observed, namely, wheezing associated with dyspnea (23.8%) and dyspnea after strenuous activities (12.3%), suggesting underdiagnosed respiratory disturbances. Further, 32.5% of all exposed workers noted an improvement of respiratory ability during resting and holidays. From all the analyzed workers, seven were previously diagnosed with asthma and four reported the first attack after the age of 40 yr, which may be associated with their occupational exposure. Some of the fungi, namely, the Aspergillus species detected in this study, are known to induce hypersensitivity reactions in humans. This study confirmed the presence and distribution of Aspergillus in Portuguese poultry and swine farms, suggesting a possible occupational health problem and raising the need for preventive and protective measures to apply to avoid exposure in both occupational settings.
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The oxovanadium(IV) complexes [VO(acac)(2)(Hpz)].HC(pz)(3) 1.HC(pz)(3) (acac= acetylacetonate, Hpz = pyrazole, pz = pyrazoly1) and [VOCl2{HOCH2C(pz)(3)}] 2 were obtained from reaction of [VO(acac)(2)] with hydrotris(1-pyrazolyl)methane or of VCl(3)with 2,2,2-tris(1-pyrazolyl)ethanol. The compounds were characterized by elemental analysis, IR, Far-IR and EPR spectroscopies, FAB or ESI mass-spectrometry and, for 1, by single crystal X-ray diffraction analysis. 1 and 2 exhibit catalytic activity for the oxidation of cyclohexane to the cyclohexanol and cyclohexanone mixture in homogeneous system (TONS up to 1100) under mild conditions (NCMe, 24h, room temperature) using benzoyl peroxide (BPO), tert-butyl hydroperoxide (TBHP), m-chloroperoxybenzoic acid (mCPBA), hydrogen peroxide or the urea-hydrogen peroxide adduct (UHP) as oxidants. 1 and 2 were also immobilized on a polydimethylsiloxane membrane (1-PDMS or 2-PDMS) and the systems acted as supported catalysts for the cyclohexane oxidation using the above oxidants (TONs up to 620). The best results were obtained with mCPBA or BP0 as oxidant. The effects of various parameters, such as the amount of catalyst, nitric acid, reaction time, type of oxidant and oxidant-to-catalyst molar ratio, were investigated, for both homogeneous and supported systems. (C) 2012 Elsevier B.V. All rights reserved.
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Intact cells from Pseudomonas aeruginosa strain L10 containing amidase were used as biocatalysts both free and immobilized in a reverse micellar system. The apparent kinetic constants for the transamidation reaction in hydroxamic acids synthesis, were determined using substrates such as aliphatic, amino acid and aromatic amides and esters, in both media. In reverse micelles, K-m values decreased 2-7 fold relatively to the free biocatalyst using as substrates acetamide, acrylamide, propionamide and glycinamide ethyl ester. We have concluded that overall the affinity of the biocatalyst to each substrate increases when reactions are performed in the reversed micellar system as opposed to the buffer system. The immobilized biocatalyst in general, exhibits higher stability and faster rates of reactions at lower substrates concentration relatively to the free form, which is advantageous. Additionally, the immobilization revealed to be suitable for obtaining the highest yields of hydroxamic acids derivatives, in some cases higher than 80%. (C) 2013 Elsevier B.V. All rights reserved.
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The Desertas Islands (Madeira, Portugal) are the sole home of one of the largest and rarest wolf spiderspecies, Hogna ingens (Blackwall 1857) (Araneae, Lycosidae). Despite its size, it inhabits a single valleyin the North of the Deserta Grande Island, Vale da Castanheira, currently invaded by the herb Phalarisaquatica. This invasive species competes with the native flora and was subject to several eradicationexperiments, namely through fire and chemicals. The objectives of this work were to: (1) estimate thecurrent distribution and abundance of H. ingens and respective trends; (2) evaluate the impact of theinvasive plant and eradication methods on the spider population; (3) suggest future measures for therecovery of the species; and (4) evaluate its conservation status according to the IUCN criteria. The current distribution of H. ingens covers 23 ha, a recent reduction from its original 83 ha, correspond-ing to the entire Vale da Castanheira. A total of 4447 and 4086 adults and 71,832 and 24,635 juvenileswere estimated to live in the valley during 2011 and 2012, respectively. We found a significant negativeimpact of P. aquatica cover on the presence and abundance of H. ingens and that chemical treatmentspecifically directed towards the invasive plant species may be the only way to effectively recover thespider's habitat. We suggest (1) regular monitoring; (2) extend chemical treatments; (3) ex-situ conserva-tion with future reintroduction of adults. Based on the current area of occupancy (AOO) of H. ingens and itsrecent decline in both AOO and number of individuals, it was recently classified as Critically Endangeredby IUCN and we suggest its urgent inclusion in the Habitats Directive species lists.
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Background: Current therapeutic strategies for advanced prostate cancer (PCa) are largely ineffective. Because aberrant DNA methylation associated with inappropriate gene-silencing is a common feature of PCa, DNA methylation inhibitors might constitute an alternative therapy. In this study we aimed to evaluate the anti-cancer properties of RG108, a novel non-nucleoside inhibitor of DNA methyltransferases (DNMT), in PCa cell lines. Methods: The anti-tumoral impact of RG108 in LNCaP, 22Rv1, DU145 and PC-3 cell lines was assessed through standard cell viability, apoptosis and cell cycle assays. Likewise, DNMT activity, DNMT1 expression and global levels of DNA methylation were evaluated in the same cell lines. The effectiveness of DNA demethylation was further assessed through the determination of promoter methylation and transcript levels of GSTP1, APC and RAR-β2, by quantitative methylation-specific PCR and RT-PCR, respectively. Results: RG108 led to a significant dose and time dependent growth inhibition and apoptosis induction in LNCaP, 22Rv1 and DU145. LNCaP and 22Rv1 also displayed decreased DNMT activity, DNMT1 expression and global DNA methylation. Interestingly, chronic treatment with RG108 significantly decreased GSTP1, APC and RAR-β2 promoter hypermethylation levels, although mRNA re-expression was only attained GSTP1 and APC. Conclusions: RG108 is an effective tumor growth suppressor in most PCa cell lines tested. This effect is likely mediated by reversion of aberrant DNA methylation affecting cancer related-genes epigenetically silenced in PCa. However, additional mechanism might underlie the anti-tumor effects of RG108. In vivo studies are now mandatory to confirm these promising results and evaluate the potential of this compound for PCa therapy.
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This paper presents a biased random-key genetic algorithm for the resource constrained project scheduling problem. The chromosome representation of the problem is based on random keys. Active schedules are constructed using a priority-rule heuristic in which the priorities of the activities are defined by the genetic algorithm. A forward-backward improvement procedure is applied to all solutions. The chromosomes supplied by the genetic algorithm are adjusted to reflect the solutions obtained by the improvement procedure. The heuristic is tested on a set of standard problems taken from the literature and compared with other approaches. The computational results validate the effectiveness of the proposed algorithm.
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New highly fluorescent calix[4]arene-containing phenylene-alt-ethynylene-3,6- and 2,7-carbazolylene polymers (CALIX-PPE-CBZs) have been synthesized for the first time and their photophysical properties evaluated. Both polymers were obtained in good isolated yields (70-84%), having M-w ranging from 7660-26,700 g mol(-1). It was found that the diethynyl substitution (3,6- or 2,7-) pattern on the carbazole monomers markedly influences the degree of polymerization. The amorphous yellow polymers are freely soluble in several nonprotic organic solvents and have excellent film forming abilities. TG/DSC analysis evidences similar thermal behaviors for both polymers despite their quite different molecular weight distributions and main-chain connectivities (T-g, in the range 83-95 degrees C and decomposition onsets around 270 degrees C). The different conjugation lengths attained by the two polymers dictates much of their photophysical properties. Thus, whereas the fully conjugated CALIX-PPE-2,7-CBZ has its emission maximum at 430 nm (E-g = 2.84 eV; Phi(F) = 0.62, CHCl3), the 3,6-linked counterpart (CALIX-PPE-3,6-CBZ) fluoresces at 403 nm with a significant lower quantum yield (E-g = 3.06 eV; Phi(F) = 0.31, CHCl3). The optical properties of both polymers are predominantly governed by the intrachain electronic properties of the conjugated backbones owing to the presence of calix[4]arenes along the polymer chain which disfavor significant interchain interactions, either in fluid- or solid-state.
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Depression, the most prevalent psychiatric disorder, has a lifelong risk of 20% and is related to high rates of death among the patients. Thus, this study aims to conduct a systematic review of changes in executive functions of adult patients diagnosed with depression. We found 1381 articles; however, only 28 were selected and recovered. The inclusion criteria was the assessment of executive functions with at least one neuropsychological test, and articles that evaluated primarily adult individuals with depression, without comparison to other psychiatric disorders. Although most of the studies (25 out of 28 analyzed) have shown deficits in some executive subcomponents, these findings are not conclusive because they used different parameters of assessment. Moreover, many variables were not controlled, such as the different subtypes of the disorder, the high level of severity, comorbidity and the use of drugs. Most studies showed different deficits in executive functions in depressed patients, but further longitudinal studies are needed in order to confirm these findings.
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Electrospun poly(vinylidene fluoride) (PVDF) fiber mats find applications in an increasing number of areas, such as battery separators, filtration and detection membranes, due to their excellent properties. However, there are limitations due to the hydrophobic nature and low surface energy of PVDF. In this work, oxygen plasma treatment has been applied in order to modify the surface wettability of PVDF fiber mats and superhydrophilic PVDF electrospun membranes have been obtained. Further, plasma treatment does not significantly influences fiber average size (~400 ± 200 nm), morphology, electroactive -phase content (~80-85%) or the degree of crystallinity (Xc of 42 ± 2%), allowing to maintain the excellent physical-chemical characteristics of PVDF. Plasma treatment mainly induces surface chemistry modifications, such as the introduction of oxygen and release of fluorine atoms that significantly changes polymer membrane wettability by a reduction of the contact angle of the polymer fibers and an overall decrease of the surface tension of the membranes.
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Electrospun poly(vinylidene fluoride) (PVDF) fiber mats find applications in an increasing number of areas, such as battery separators, filtration and detection membranes, due to their excellent properties. However, there are limitations due to the hydrophobic nature and low surface energy of PVDF. In this work, oxygen plasma treatment has been applied in order to modify the surface wettability of PVDF fiber mats and superhydrophilic PVDF electrospun membranes have been obtained. Further, plasma treatment does not significantly influences fiber average size (~400 ± 200 nm), morphology, electroactive -phase content (~80-85%) or the degree of crystallinity (Xc of 42 ± 2%), allowing to maintain the excellent physical-chemical characteristics of PVDF. Plasma treatment mainly induces surface chemistry modifications, such as the introduction of oxygen and release of fluorine atoms that significantly changes polymer membrane wettability by a reduction of the contact angle of the polymer fibers and an overall decrease of the surface tension of the membranes.