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Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
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We propose a new self-organizing neural model that performs principal components analysis. It is also related to the adaptive subspace self-organizing map (ASSOM) network, but its training equations are simpler. Experimental results are reported, which show that the new model has better performance than the ASSOM network.  相似文献   
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Background and objectiveTo analyse frequency, characteristics and patient survival with lung cancer (LC) and Common Obstructive Pulmonary Disease (COPD), comparing them with patients that do not have COPD.Material and methodsA retrospective study, of patients diagnosed by means of cytohistology. Survival was estimated by the Kaplan-Meier method. Statistical analysis was carried out using SPSS 15.0.ResultsA total of 996 patients were diagnosed, 39.8% with COPD. Mean age70±9.19 years. GOLD stages: I 18.2%, II 53.6%, III 24%, IV 4.2%. The histological types: squamous cell carcinoma 48.2%, adenocarcinoma 22%, and small cell carcinoma 22.5%. Survival was longer in the COPD group.ConclusionsLC and COPD are combined in 39.8%. Squamous cell type is more frequent and survival was longer in the COPD group.  相似文献   
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Background and ObjectiveSchool smoking prevention programs have never yielded the expected results. The aim of this study was to analyze the efficacy of an intensive smoking prevention program created by the educational community in which it was to be applied.Population and MethodA 3-year smoking prevention program was carried out among the students of Fuentesaúco Secondary School in Zamora, Spain. The Babilafuente Secondary School in Salamanca, Spain was the control group. The program included both prevention and treatment activities. The former were carried out in the school, in out-of-school situations, and in the community. The questionnaire of the European Smoking Prevention Framework Approach was used.ResultsA total of 417 students aged 12 to 17 years participated in the study. Of these, 54.4% belonged to the intervention group and 45.6% to the control group. Smokers represented 36.7% of the population. After the intervention smokers represented 40.1% of the Fuentesaúco students compared with 46.1% of the Babilafuente students, though the difference was not statistically significant. With respect to the cognitive determinants of smoking behavior, after the intervention significant differences in favor of the intervention group were only observed in the subjects’ perception of the behavior of their siblings, peers, and teachers.ConclusionsThe use of smoking prevention programs in schools should be reconsidered, and their evaluation should be based on educational rather than clinical criteria. Proposed changes in the program include decreasing its intensity, starting with students of an earlier age and seeking greater involvement of parents.  相似文献   
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ObjectiveTo assess whether the release of the new consensus algorithms in August 2006, along with the consensus recommendation of also using metformin as first choice in patients with normal weight, has led to an increase in the use of this drug in the period immediately after.DesignRetrospective longitudinal Study.SitesSantiago de Compostela Health District (A Coruña).ParticipantsUsers of the Galician health service in the Santiago de Compostela Health District.MethodsThe evolution of the monthly number of DHD (Daily Defined Doses/1000 inhabitants/day) of metformin from early 2003 until 12 months after the issuing of new algorithms was analysed graphically and using a multiple regression model.ResultsThe graphical representation of the DHD of metformin over time shows a linear growth for the period, but there is an increasing trend after the publication of the new consensus algorithm. The multiple regression showed that the increase is statistically significant.ConclusionsFollowing the publication of the new consensus algorithm an increasing trend in the use of metformin is observed in the short term.  相似文献   
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