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991.
Title.  Nurse education: factors associated with attrition.
Aim.  This paper is a report of a study to identify the factors having an impact on student completion rates in a preregistration programme.
Background.  Nursing student attrition is an international issue causing concern in many parts of the developed world including Australia, the United States and Europe. In the United Kingdom, nursing student attrition has become a major issue, despite having one of the lowest general university dropout rates in the developed world.
Method.  A retrospective cohort study was conducted in 2007 using routinely-collected demographic and completion data on four cohorts of nursing students (1259 in total) studying at a large English university.
Findings.  Students who were older on entry were more likely to complete the programme than younger students, and those who had only the minimum educational qualifications on entry were less likely to complete than those with higher-level qualifications. There was some evidence of increased risk of resigning from the course in students taking the child branch, and increased risk of discontinuation (involuntary removal) from the course in both male and black/minority ethnic students. There was also some evidence that the healthcare organization responsible for a student's placement could influence completion rates.
Conclusion.  To improve attrition rates on preregistration nursing programmes, higher education institutions should actively target recruitment at mature candidates; increase the level of qualification required to gain entry; examine course structures for flexibility and provide multi-level student support.  相似文献   
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996.
BACKGROUND: Streptococcus pneumoniae is a leading cause of invasive bacterial disease and pneumonia among children. Antimicrobial resistance among pneumococci has increased in recent years and complicates treatment. The introduction of heptavalent pneumococcal conjugate vaccine (PCV7) could reduce acquisition of antimicrobial-resistant pneumococci. METHODS: We obtained 1350 nasopharyngeal swabs for culture from 1275 children aged 3-59 months presenting at 3 clinics in Anchorage, Alaska, during the winters of 2000, 2001, and 2002, as PCV7 was being introduced into the routine immunization schedule. We recorded the frequency of use of antibiotics as well as the dates of doses of PCV7 for enrolled children. We used multivariate logistic regression modeling to identify independent risk factors for overall carriage of pneumococci and carriage of PCV7-type pneumococci, cotrimoxazole-nonsusceptible (COT-NS) pneumococci, or penicillin-nonsusceptible (PCN-NS) pneumococci. RESULTS: The proportion of children who were up-to-date for age, with respect to PCV7 vaccination, increased from 0% in 2000 to 55% in 2002. Carriage of PCV7-type pneumococci decreased by 43% (P<.0001). Risk of carriage of PCV7-type pneumococci was lower in 2002 than in 2000, independent of vaccination status, suggesting an indirect effect of vaccination. Carriage of COT-NS, but not PCN-NS, pneumococci also decreased (38%; P=.02), not only among vaccinated children but also among unvaccinated children without recent use of antibiotics. CONCLUSIONS: Introduction of PCV7 into the routine infant immunization schedule in a community with a high prevalence of antimicrobial-resistant pneumococci appears to reduce transmission of PCV7 vaccine serotypes and COT-NS pneumococci but has no impact on overall carriage of pneumococci or carriage of PCN-NS pneumococci.  相似文献   
997.
Objectives. The aim of this study was to assess the cardiovascular effects of BAY y 5959, a calcium promoter modulating myocardial calcium channels, in the presence or absence of congestive heart failure.

Background. There is still a clinical need for short-term administration of intravenous positive inotropes. BAY y 5959 was developed as a new approach to increase myocardial performance by selectively enhancing calcium influx in the myocytes.

Methods. Forty-one patients (21 without and 20 with congestive heart failure) were studied in an open label, dose-ranging study. Hemodynamic variables (including left ventricular [LV] angiography) and plasma samples were obtained at baseline and after 20 min of intravenous infusion of BAY y 5959 at doses ranging from 0.25 to 4.5 μg/kg body weight per min.

Results. In both study groups, BAY y 5959 produced dose-dependent increases in the indexes of inotropic state, without affecting isovolumetric relaxation rate. The magnitude of the response was comparable in patients with or without heart failure (average 38% increase in maximal first derivative of LV pressure [dP/dt max] at plasma levels of 100 μg/liter). BAY y 5959 also induced mild but statistically significant bradycardia and significantly decreased end-systolic volume while producing a leftward shift of the pressure-volume loop. Mean aortic pressure was unaffected at doses up to 3.0 μg/kg per min, and cardiac index improved in patients with heart failure at doses of 2.0 μg/kg per min (+23%, p < 0.05). However, at a dose of 4.5 μg/kg per min, mean aortic pressure and LV systolic wall stress increased, suggesting systemic vasoconstriction. The QT interval was also prolonged significantly at most doses.

Conclusions. BAY y 5959 exhibits positive inotropic effects in patients with and without heart failure. The optimal response— combining bradycardia, reduced preload and improved cardiac output—appeared to be achieved at a dose of 2.0 μg/kg per min. The impact of QT prolongation with regard to potential antiarrhythmic or proarrhythmic effects is unclear at this time.  相似文献   

998.
The liver is the major source of reduced glutathione (GSH) in blood plasma. The transport protein mediating the efflux of GSH across the basolateral membrane of human hepatocytes has not been identified so far. In this study we have localized the multidrug resistance protein 4 (MRP4; ABCC4) to the basolateral membrane of human, rat, and mouse hepatocytes and human hepatoma HepG2 cells. Recombinant human MRP4, expressed in V79 hamster fibroblasts and studied in membrane vesicles, mediated ATP-dependent cotransport of GSH or S-methyl-glutathione together with cholyltaurine, cholylglycine, or cholate. Several monoanionic bile salts and the quinoline derivative MK571 were potent inhibitors of this unidirectional transport. The K(m) values were 2.7 mmol/L for GSH and 1.2 mmol/L for the nonreducing S-methyl-glutathione in the presence of 5 micromol/L cholyltaurine, and 3.8 micromol/L for cholyltaurine in the presence of 5 mmol/L S-methyl-glutathione. Transport of bile salts by MRP4 was negligible in the absence of ATP or without S-methyl-glutathione. These findings identify a novel pathway for the efflux of GSH across the basolateral hepatocyte membrane into blood where it may serve as an antioxidant and as a source of cysteine for other organs. Moreover, MRP4-mediated bile salt transport across the basolateral membrane may function as an overflow pathway during impaired bile salt secretion across the canalicular membrane into bile. In conclusion, MRP4 can mediate the efflux of GSH from hepatocytes into blood by cotransport with monoanionic bile salts.  相似文献   
999.
Physician accuracy in diagnosing colorectal polyps   总被引:3,自引:4,他引:3  
Since the medical management of persons with adenomatous colorectal polyps differs from that of those with hyperplastic polyps, accuracy of diagnosis is essential. Although many physicians have grown confident that their skills of visual diagnosis are adequate, few data exist to support this confidence. In order to examine the accuracy of physicians' judgments regarding colorectal polyp histology, the visual diagnosis of physicians experienced in endoscopy was compared with the histologic report. Eighty-one polyps were discovered by flexible sigmoidoscopy among 718 participants in a colon cancer screening program. Eighty percent of all polyps were detected accurately. The diagnostic sensitivity of detecting adenomas was 69 percent, while specificity (accurate diagnosis of hyperplastic polyps) was 86 percent, and there were an additional eight false negative and eight false positive diagnoses. Further analyses revealed that there are individual patterns of diagnostic mistakes made by physicians and that mistakes frequently are related to polyp size. These findings are particularly important in light of the expanding numbers of relatively inexperienced primary care providers performing flexible sigmoidoscopy whose diagnoses may be strongly dependent on polyp size. This research was done through, and supported by, the Center for Occupational Health, Department of Family Medicine, Wayne State University, Detroit, Michigan.  相似文献   
1000.
Reactive arthritis (ReA) is sterile arthritis occurring after extra articular bacterial infection. The aim of this study was to analyze, over 30 years, clinical, biological and imaging characteristics as well as therapeutic management of new cases of ReA, comparing two periods.

Methods

retrospective monocentric study, data of all the patients followed in our unit between January 1st 1984 and April 2014 with the diagnosis or ReA were analyzed (clinical and biological features, management and outcome), and compared between two periods: from January 1984 to December 1993, and from January 2004 to December 2013.

Results

Sixty two patients fulfilling international diagnosis criteria were analyzed. There was no significant difference between the two periods in number of new cases, clinical presentation, biological data or outcome. Changes in therapeutic management were obvious with occurrence of anti TNF in the recent period.

Conclusion

Reactive arthritis is still a current rheumatologic problem in a developed country, with a need of early and tailored rheumatologic management.  相似文献   
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