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Bioavailability and biological properties of flavonoid glycosides can be improved after the enzymatic hydrolysis of specific glycosyl groups. In this study, we evaluate the antioxidant and antiproliferative potential of rutin after enzymatic hydrolysis performed by α-l-rhamnosidases (hesperidinase from Penicillium sp. and naringinase from Penicillium decumbens) previously heated at 70 °C for 30 min to inactivate the undesirable β-d-glucosidase activity. The highest in vitro antioxidant activity determined by DPPH radical scavenging was achieved with rutin hydrolyzed by hesperidinase. Rutin was predominantly bioconverted into quercetin-3-glucoside. There was no statistical difference between xanthine oxidase inhibition by rutin before and after hydrolysis. However, in vitro inhibitory activity against ten human tumor cell lines showed that hydrolyzed rutin exerted a more potent antiproliferative effect than quercetin and rutin on various cancer cell lines, specially glioma, and ovarian and breast adenocarcinomas. These results indicate that quercetin-3-glucoside could be a promising functional derivative obtained by rutin hydrolysis.  相似文献   
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At a time when communication, new media, and digitalization are transversal to the whole of society, private health care organizations have the possibility of making their business processes evolve. The objective is thus to seize the benefits associated to the active use of patients' electronic health records (EHRs) as the basis for personalized health care. In order to initially validate the health care sector acceptance of a 360° health care information system (HIS), focused on collecting patients' data to create the necessary knowledge for delivering personalized health care procedures and initiatives, a focus group involving a set of health-related professionals was performed. Despite recognizing the immense possibilities associated to EHR and its direct incorporation on a 360° HIS, the referred professionals still highlighted their concerns relative to the maintenance of adequate security and privacy levels. With this in mind, a proposal for a 360° HIS model is presented, and its main functional blocks are described with a focus on triggering patient/customer loyalty.  相似文献   
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OBJECTIVE: As fungal endocarditis is a serious disease, frequently requiring cardiac surgery, a review was made of the experience of our Departments in this pathology. DESIGN: A retrospective analysis of clinical, echocardiographic and surgical data. SETTING: Patients studied in a tertiary care Hospital with cardiac surgery available. PATIENTS: Between 1984 and 1994 there were ten cases of candida endocarditis in nine patients, four male and five female, mean age--45 +/- 12 years (31-65). INTERVENTIONS: The following parameters were analysed: clinical (predisposing factors, clinical evolution, complications, therapy and mortality), echocardiographic (presence of vegetations, abscesses, valvular regurgitations). Patients studied in other Centres and referred to our Department only for examination (echocardiograms) were excluded from this analysis. RESULTS: Eight cases in seven patients were prosthetic valve endocarditis and two native valve endocarditis. No patient was drug addicted. Seven cases of prosthetic valve endocarditis developed less than one year after surgery and another had a gynecological fungal infection as the cause of the endocarditis. Four patients had had previous endocarditis. There were four embolic events and three developed heart failure. There were three perivalvular infections, six valvular regurgitations and only one case with huge vegetations on echocardiography. Nine patients were treated with amphotericin B, in five fluocytosin was added and in four ketoconazol, which was replaced by flukonazol in one patient. Therapy was continued for at least eight weeks. Six patients were operated during the acute stage and one died. One patient was operated on late after the infection. Three patients died during the active stage. In a follow up of 5.2 +/- 4.8 years (8 months to 8 years) there was one fatal candida endocarditis relapse, one fatal candida sepsis, one non cardiac death, one patient developed a periprosthetic leak and one had recurrent systemic embolization. Abscesses/pseudoaneurysms were found in five out of seven patients submitted to surgery. CONCLUSION: Candida infective endocarditis has a bad prognosis, specially in those patients not operated early; it develops in patients with predisposing factors, which in our series were a previous infective endocarditis (four patients) and/or a prosthetic valve implantation less than one year before; it has important morbidity with multiple embolic events, perivalvular involvement, valvular regurgitation and heart failure.  相似文献   
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Millennials interact with technology like no other generation before them and this is affecting how they want to be taught in higher education and how they want to lead and expect to be led in organizations, after graduating. Though stating that they want to be enlightened in academia, some qualitative comments from millennials indicate the opposite, namely that they want to be prepared but also to be kept naïve as to what business really entails. This is expected to help keep motivation levels high, as motivation is seen to be the key element to success in life. Millennials expect also to be led authentically and to be treated as valued human beings. This is in contrast to the current autocratic leadership profile found predominantly in Portuguese organizations, at the time of writing. This study had a sample of one hundred and eleven millennial students who answered a survey on attitudes towards leadership and their desired approach to higher education. Three interviews with seasoned executives were also performed, to establish a contrast and see other perspectives.With this research, we conclude that we may be in the presence of a hard working millennial generation, contrary to previous research findings which has indicated that they are lazy. Finally, information technology (IT) is a precious partner in class, in particular Padlet.com, Moodle, and online News Forums, as well as the challenge to create original videos about course content. Future research should focus on how technology has made society more transparent with employees wanting more democratic leaders in times when hierarchies are seen to hinder rather than aid productivity levels.  相似文献   
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Considering the importance associated with e-commerce website accessibility and usability, a study on one of the most relevant Portuguese e-commerce websites has been performed using both automatic and manual assessment procedures. In an initial stage, we evaluated the chosen website with a Web accessibility and usability automatic tool called SortSite; after that, we performed a manual evaluation to verify each previously detected error and present possible solutions to overcome those faults. In a third phase, three usability specialists have been used to perform a heuristic evaluation of the chosen website. Finally, user tests with blind people were carried out in order to fully assess the compliance with accessibility and usability guidelines and standards. The results showed that the platform had a good score regarding the automatic evaluation; however, when the heuristic and manual evaluations were performed, some accessibility and usability problems were discovered. Moreover, the user test results showed bad marks regarding efficiency, effectiveness, and satisfaction by the group of participants. As a conclusion, we highlight user interaction problems and propose seven recommendations focused on enhancing accessibility and usability of not only the evaluated e-commerce website, but also of other similar ones.  相似文献   
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Modern hardware is abundantly parallel and increasingly heterogeneous. The numerous processing cores have non-uniform access latencies to the main memory and processor caches, which causes variability in the communication costs. Unfortunately, database systems mostly assume that all processing cores are the same and that microarchitecture differences are not significant enough to appear in critical database execution paths. As we demonstrate in this paper, however, non-uniform core topology does appear in the critical path and conventional database architectures achieve suboptimal and even worse, unpredictable performance. We perform a detailed performance analysis of OLTP deployments in servers with multiple cores per CPU (multicore) and multiple CPUs per server (multisocket). We compare different database deployment strategies where we vary the number and size of independent database instances running on a single server, from a single shared-everything instance to fine-grained shared-nothing configurations. We quantify the impact of non-uniform hardware on various deployments by (a) examining how efficiently each deployment uses the available hardware resources and (b) measuring the impact of distributed transactions and skewed requests on different workloads. We show that no strategy is optimal for all cases and that the best choice depends on the combination of hardware topology and workload characteristics. Finally, we argue that transaction processing systems must be aware of the hardware topology in order to achieve predictably high performance.  相似文献   
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