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This study investigates the incidence and determinants of hospital readmissions among elderly patients in Norway. The analyses are based on registered data on inpatient admissions to public hospitals from 1999 to 2006. During this period, mean length of stay in hospital decreased, while readmission rates increased. Probit and instrumental variable regression models are applied for the analyses. The results indicate that longer length of stay in the hospital is associated with lower probability of readmission. A patient’s age, comorbidities, and complexity of the treatment procedure are positively associated with readmissions, while higher number of diagnostic procedures negatively affects hospital readmission. Finally, patients discharged to institutions are more likely to be readmitted to the hospital.  相似文献   
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HIV-1 recombinants between viruses from different subtypes appear to be surprisingly common in several regions of the world. To detect such intersubtype recombinants that contain mosaic genomes, we have analyzed sequences from the integrase (IN)-coding region of the polymerase (pol) gene from 23 viruses of known envelope (env) subtype from South America and Africa. As defined by env sequences, these viral genomes included nine subtype A, four subtype B, three subtype C, and four subtype D viruses from group M, and three viruses from group O HIV-1. Mosaic genomes were common, with 7 mosaic genomes among the 20 group M isolates analyzed. Two of these isolates had mosaic IN-coding regions that were distinct, but that had recombination breakpoints at the same location, in the highly conserved polypurine track. Mosaic genomes were particularly common in the viruses from Kenya (five of nine), consistent with our previous prediction that there was a high frequency of intersubtype recombinants circulating in this country. The IN amino acid sequence was highly conserved among the several represented subtypes, including group O. Group M IN sequences shared 94% or greater amino acid sequence identity within a subtype and 91% or greater identity between subtypes. The most divergent M and O variant amino acid sequences differed by only 19%, and the known functional domains were conserved among all of the isolates. The high degree of genetic homogeneity among the virus isolates representing several subtypes indicates that a single drug targeted against IN might be effective for all HIV-1 infections.  相似文献   
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Objective: To compare the effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome (PFPS). Methods: Twenty-eight PFPS patients and 28 controls participated in the study. Postural control was assessed in isolation as well as with visual manipulation and cognitive loading on symptomatic limb. The outcome measures of postural control were quantified in terms of area, anterior-posterior (AP), medial-lateral (ML), and mean velocity (MV) of the displacements of center of pressure (COP). In addition, cognitive performance (auditory Stroop task) was measured in the forms of average reaction time and error ratio in baseline (sitting) and different postural conditions. Results: PFPS subjects showed greater increases in area (p = 0.01), AP (p = 0.01), and ML (p = 0.05) displacements of COP in the blindfolded tasks as compared to control group. However, cognitive load did not differently affect postural control in the two groups. Although PFPS and control group had similar reaction times in the sitting position (p = 0.29), PFPS subjects had longer reaction times than healthy subjects in dual task conditions (p = 0.04). Conclusion: Visual inputs seem to be essential for discriminating postural control between PFPS and healthy individuals. PFPS patients biased toward decreasing cognitive performance more than healthy subjects when they perform the single leg stance and cognitive task concurrently.  相似文献   
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Background

Work-related accidents result in human suffering and economic losses and are considered as a major health problem worldwide, especially in the economically developing world.

Objectives

To introduce seasonal autoregressive moving average (ARIMA) models for time series analysis of work-related accident data for workers insured by the Iranian Social Security Organization (ISSO) between 2000 and 2011.

Methods

In this retrospective study, all insured people experiencing at least one work-related accident during a 10-year period were included in the analyses. We used Box–Jenkins modeling to develop a time series model of the total number of accidents.

Results

There was an average of 1476 accidents per month (1476·05±458·77, mean±SD). The final ARIMA (p,d,q) (P,D,Q)s model for fitting to data was: ARIMA(1,1,1)×(0,1,1)12 consisting of the first ordering of the autoregressive, moving average and seasonal moving average parameters with 20·942 mean absolute percentage error (MAPE).

Conclusions

The final model showed that time series analysis of ARIMA models was useful for forecasting the number of work-related accidents in Iran. In addition, the forecasted number of work-related accidents for 2011 explained the stability of occurrence of these accidents in recent years, indicating a need for preventive occupational health and safety policies such as safety inspection.  相似文献   
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Background:

The number of malaria cases is declining worldwide; however, it remains as a serious health problem. Diagnosing unusual cases is the most important issue to manage the problem. This study designed to describe the number of falciparum and vivax malaria infected patients referred to Malaria Reference Laboratory in Tehran University of Medical Science from 2000 to 2012.

Methods:

A retrospective study was conducted based on the collected questionnaires from each patient referred to the laboratory. Diagnosing results and demographic information for positive cases were analyzed using SPSS software. Problematic cases were evaluated for any difficulties in diagnosis or in clinical signs. Scanning and molecular methods were performed whenever there was an atypical case referred to the laboratory. Some of the samples had various difficulties for diagnosing such as presence of fussed gametocytes and schizonts of Plasmodium falciparum in peripheral blood and CCHF like hemoragic disorders.

Results:

Plasmodium vivax caused a large proportion of the cases (76.1%) in contrast with P. falciparum that included smaller proportion (22.8%) and the rest (1.1) belonged to mixed infection. Most of the positive cases (69.6%) were belonged to Afghani people. Men (94.6%) showed more infection than women (5.4%), moreover the most infection (44.5%) was seen at a range of 21–30 yr.

Conclusion:

In the case of existing atypical issues to diagnose, it is needed to perform more precise microscopical examination beyond the current standard conditions. Sometimes molecular method is required to verify the exact agent of the disease.  相似文献   
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Polymeric micelles for drug targeting   总被引:2,自引:0,他引:2  
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