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OBJECTIVE: To determine, over time, the rate and serotypes of pneumococci with reduced penicillin susceptibility obtained from children with invasive infection. DESIGN: Active, hospital-based, multicentre surveillance spanning from 1991 to 1998. SETTING: Eleven Canadian tertiary care paediatric facilities located from coast to coast. POPULATION STUDIED: 1847 children with invasive pneumococcal infection whose isolates (from a normally sterile site) were available for serotyping and standardized testing for penicillin susceptibility at the National Centre for Streptococcus. MAIN RESULTS: The prevalence of reduced penicillin susceptibility increased from 2.5% of 197 cases in 1991 to 13.0% of 276 cases in 1998. In the latter year, 8.7% of isolates had intermediate level resistance, and 4.3% had high level resistance. Since they were first detected in 1992, strains with high level resistance have been encountered only sporadically at most centres, but by 1998, all centres but two had encountered examples. Of 40 isolates with high level resistance and 101 isolates with intermediate level resistance, serotypes matched those included in new seven-valent conjugate vaccines for children in 97.5% and 79.2% of cases, respectively. CONCLUSIONS: Pneumococci with reduced susceptibility to penicillin are increasing in frequency across Canada among children with invasive infection. The Immunization Monitoring Program, Active data indicate that new conjugate vaccines could help to curb infections due to pneumococci with reduced susceptibility to penicillin but are unlikely to control completely the problem of antibiotic resistance.  相似文献   
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T Leese  J P Neoptolemos  K P West  I C Talbot    D L Carr-Locke 《Gut》1986,27(10):1186-1192
From a large series of patients referred for endoscopic retrograde cholangiopancreatography to one endoscopist, 49 patients had the duodenoscopic appearance of a periampullary tumour. Thirty eight of these lesions were neoplastic, but the remaining 11 patients had inflammatory non-neoplastic lesions (pseudotumours). These could not be distinguished from the neoplasms on endoscopic appearances. The cholangiopancreatograms were similar except that the diameter of the pancreatic duct tended to be higher in the tumour group and gall stones were present significantly more often in the patients with pseudotumour. Endoscopic biopsy correctly diagnosed 28 of 34 ampullary carcinomas. Two of the 11 pseudotumour patients were subjected to surgical excision biopsy because of suspicious histological features of endoscopic biopsy. In the neoplastic group 19 patients underwent Whipple's procedure, seven surgical bypass, seven endoscopic sphincterotomy only and five died without successful biliary drainage. The overall one year survival was 44.7%. By contrast, the patients with pseudotumours were clinically well at a median follow up 24 months (range 12-41 months), after endoscopic sphincterotomy except for one 89 year old patient who died 22 months later from unrelated causes.  相似文献   
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The differential diagnosis of ankle pain is extensive. Pathology may be classified as intra- or extra-articular. Additionally, ankle pain may be traumatic or non-traumatic. One of the unusual differential diagnoses for pain in the ankle is an accessory muscle. Magnetic resonance imaging is the radiological investigation of choice. However, this is invariably reported as normal unless one specifically looks for an accessory muscle. The purpose of this report is to highlight important features of these muscles and to draw attention to this uncommonly reported condition.  相似文献   
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Objective

This study seeks to examine how the extent of socioeconomic deprivation, racial and ethnic isolation, and health disadvantage differ among Medicare beneficiaries in Mississippi. Methods: Geographical information system (GIS) mappings are used in conjunction with cluster analysis to examine patterns of disparities in disease distribution, healthcare utilization and socioeconomic well-being among different counties in Mississippi.

Results

Results reveal that counties in these two clusters are markedly different in terms of socio-economic well-being but are somewhat similar in terms of disease distributions and healthcare utilization.

Conclusion

Addressing the geographic disparities in disease distribution and healthcare utilization that exist among the counties should be a public health priority. Specifically, health policies and programs should be renewed to target people living in counties that are either predominantly rural or predominantly Black or have higher percentages of population living below the poverty level.  相似文献   
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