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991.
BACKGROUND: The gold standard for surgical treatment of chronic frontal sinusitis has been the osteoplastic flap with obliteration. In an attempt to preserve the frontal sinus, we have been performing the endoscopic modified Lothrop orfrontal drill-out. METHODS: Retrospective chart review. RESULTS: We performed the modified Lothrop on 54 patients between 1993 and 1998. The modified Lothrop was successful (no revision surgeries and only an occasional need for antibiotics) after one procedure in 68% (30/44) of patients followed up for > or =1 year. Six patients underwent successful revision, bringing the overall success rate to 82% (36/44). Eight patients (18%) eventually underwent osteoplastic flap with obliteration, three of those after attempted revision. Mean follow-up was 40 months with failures occurring a mean of 12 months after initial Lothrop. Overall complication rate was 11%. CONCLUSIONS: The modified Lothrop is a technically challenging operation that provides an acceptable alternative to the osteoplastic flap with obliteration.  相似文献   
992.
PURPOSE: To describe the epidemiology of invasive pneumococcal infections in Canadian children 0 to 12 years old. METHODS: At each of nine urban centers, active surveillance was conducted to identify all cases of invasive pneumococcal infection in children during 1994 to 1998. Postal codes were used to distinguish cases resident in defined urban areas from referral cases. Census data were obtained for each defined area to calculate age-specific incidence rates. Features of population-based cases were described. RESULTS: From an average defined population of approximately 1 million children, 937 eligible cases arose. Those 6 to 17 months old had the highest average incidence rate of 98.6/100 000/year. The average cumulative risk of infection was 1 in 460 between birth and 59 months, by which age 92% of cases had occurred. Among cases younger than 2 years of age, simple bacteremia accounted for 66%, pneumonia with bacteremia accounted for 14.7% and meningitis accounted for 11% (average incidence rate, 9.0/100 000/year). An underlying illness was present in 16% of all cases. The mortality rate was 1.8%. CONCLUSIONS: Invasive pneumococcal infections are relatively common in early childhood, based on 5 years of data from nearly 20% of the Canadian population ages 0 to 12 years. These data will be valuable for calculating the economic case for universal infant vaccination with newly available vaccines.  相似文献   
993.
994.
This article reviews the recent progress in the search for new treatments for renal cell cancer (RCC), based on a variety of preclinical models or strategies. Some recent clinical trials addressing migrating treatments from other cancers onto RCC and novel agents are discussed, as well as the molecular targets for some of the novel agents. Drugs oriented to histologically definable RCC features, such as the G250 antigen, and the receptor tyrosine kinases, such as epidermal growth factor receptor, are reviewed. Drugs aimed at antiangiogenesis and perturbing features of the cell cycle are also mentioned, including preclinical and empirical experience. Molecular techniques in the study of von Hippel Lindau-related pathways and mRNA expression analyses are cited. Within the immune model of therapy, progress in the application of immune-related drugs including older cytokines (IL-2, IFN-alpha) and of newer cytokine-variant and other cytokines are discussed. Finally, cell-based therapies such as lymphocyte infusions, tumour-cell vaccines, dendritic cell vaccines and allogeneic mini-transplant are outlined. Although high percentage improvements in outcomes for metastatic RCC are not yet realised, the many fronts for scientific and clinical advances form some basis for optimism in the coming years.  相似文献   
995.
Benzo(a)pyrene diol epoxide (BPDE), an active metabolite of the tobacco carcinogen benzo(a)pyrene, can induce p53 gene mutation, down-regulate retinoic acid receptor beta, and increase cyclooxygenase-2 expression in human epithelial cells. However, it remains unknown whether these effects are direct or indirect. To investigate the direct effects of BPDE on gene expression, we used our newly developed DNA immunoprecipitation technique to identify and clone BPDE-binding DNA fragments. A total of 67 fragments were sequenced and grouped into four categories after their sequences were blasted in the GenBank database: (a). 15 fragments matched known gene sequences; (b). 24 matched expressed sequence tag clones; (c). 22 matched genomic DNA of unknown genes; and (d). 6 clones did not show any homology with GenBank sequences known to date. The 67 fragments include DNA repair and apoptosis-related genes, zinc finger protein, cellular enzymes, expressed sequence tag clones, and CpG islands. These data further demonstrate that BPDE-induced gene alterations are important events in carcinogenesis and that the identification of the resulting clones may help us to better understand the mechanisms of BPDE-induced carcinogenesis.  相似文献   
996.
997.
The labour market for nursing: a review of the labour supply literature   总被引:3,自引:0,他引:3  
The need to ensure adequate numbers of motivated health professionals is at the forefront of the modernisation of the UK NHS. The aim of this paper is to assess current understanding of the labour supply behaviour of nurses, and to propose an agenda for further research. In particular, the paper reviews American and British economics literature that focuses on empirical econometric studies based on the classical static labour supply model.American research could be classified into first generation, second generation and recent empirical evidence. Advances in methods mirror those in the general labour economics literature, and include the use of limited dependent variable models and the treatment of sample selection issues. However, there is considerable variation in results, which depends on the methods used, particularly on the effect of wages.Only one study was found that used UK data, although other studies examined the determinants of turnover, quit rates and job satisfaction. The agenda for further empirical research includes the analysis of discontinuities in the labour supply function, the relative importance of pecuniary and non-pecuniary job characteristics, and the application of dynamic and family labour supply models to nursing research. Such research is crucial to the development of evidence-based policies.  相似文献   
998.
OBJECTIVE: To compare the impact of weight regain and weight loss on health-related quality of life. RESEARCH METHODS AND PROCEDURES: Subjects were 122 (106 women, 16 men) overweight and obese participants in a weight reduction program (phentermine-fenfluramine and dietary counseling) who had initially lost at least 5% of their total body weight and then regained at least 5% of their weight during the follow-up period. Follow-up periods ranged from 10 to 41 months (mean, 28 months). Participants completed the Impact of Weight on Quality of Life-Lite, an obesity-specific health-related quality of life (HRQOL) measure, at 3-month intervals. RESULTS: Mean BMI at baseline was 40.9 +/- 6.6 kg/m(2) (range, 29.2 to 63.7 kg/m(2)). Average weight loss from entry was 18.8 +/- 6.7% (range, 6.0% to 43.7%), and average regain was 10.1 +/-4.4% of baseline weight (range, 5.0% to 30.6%). The effects of weight regain on HRQOL mirrored the effects of weight loss-rates of HRQOL change were similar in magnitude but different in direction for comparable weight loss and regain. Those with more severe initial impairments in HRQOL experienced greater improvements in HRQOL during weight loss as well as greater deterioration during weight regain than those with less severe impairments. DISCUSSION: Weight loss and regain produced mirror image changes in HRQOL. The initial severity of HRQOL impairment had a greater impact on the magnitude of HRQOL change than the direction of weight change. Findings underscore the importance of maintaining weight loss for the purposes of retaining obesity-specific HRQOL benefits.  相似文献   
999.
Seasonal patterns of invasive pneumococcal disease   总被引:5,自引:0,他引:5  
Pneumococcal infections increase each winter, a phenomenon that has not been well explained. We conducted population-based active surveillance for all cases of invasive pneumococcal disease in seven states; plotted annualized weekly rates by geographic location, age, and latitude; and assessed correlations by time-series analysis. In all geographic areas, invasive pneumococcal disease exhibited a distinct winter seasonality, including an increase among children in the fall preceding that for adults and a sharp spike in incidence among adults each year between December 24 and January 7. Pneumococcal disease correlated inversely with temperature (r -0.82 with a 1-week lag; p<0.0001), but paradoxically the coldest states had the lowest rates, and no threshold temperature could be identified. The pattern of disease correlated directly with the sinusoidal variations in photoperiod (r +0.85 with a 5-week lag; p<0.0001). Seemingly unrelated seasonal phenomena were also somewhat correlated. The reproducible seasonal patterns in varied geographic locations are consistent with the hypothesis that nationwide seasonal changes such as photoperiod-dependent variation in host susceptibility may underlie pneumococcal seasonality, but caution is indicated in assigning causality as a result of such correlations.  相似文献   
1000.
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