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1.
One hundred sixty-two white-blood-cell scans were retrospectively reviewed to determine the sensitivity and specificity of the test for pulmonary and pleural infection. All scans were performed 18-24 hr after injection of indium-111 oxine-labeled autologous or donor cells. Pulmonary activity was graded on a scale of 0-4: 0 = equal to soft tissue; 1 = greater than soft tissue but less than rib; 2 = equal or greater than rib but less than liver; 3 = equal or greater than liver but less than spleen; 4 = equal to spleen. Activity was also characterized as being focal or diffuse. The white-blood-cell scan findings were correlated with the clinical diagnosis on the basis of physical examination, laboratory results, chest radiographs, clinical course, and pathologic studies when available. As pulmonary activity increased from grade 1 to 4, sensitivity declined from 93% to 14% and specificity increased from 64% to 100%. The sensitivity and specificity of focal uptake were 31% and 89% vs 62% and 74% for diffuse pulmonary activity. Making a distinction between focal and diffuse activity did not improve the specificity of low grades of pulmonary activity. The white-blood-cell scan can be very sensitive or very specific for pulmonary or pleural infection, depending on the criteria selected for a positive scan.  相似文献   
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Chronic polypoid rhinosinusitis (CRS) is a common disease, affecting approximately 16% of the adult population in the US every year. In addition to many well known predisposing factors, an association with reflux disease is hypothesized. Such an association might explain the recurrence of polyposis in the face of improved surgical techniques and postsurgical treatment of CRS. At present it is unclear whether extraesophageal reflux directly injures the sinus mucosa, whether gastroesophageal reflux leads to vagus-mediated neuroinflammatory changes, or whether both mechanisms occur separately or simultaneously. In patients suffering from recurrent CRS (n=20) and healthy volunteers (n=20), ambulatory 24 h two channel pH testing was performed. The number of reflux events, the fraction of the total time during which pH was below 4, and the reflux area index (RAI) were determined in the esophagus as well as in the hypopharynx. Patients with recurrent CRS had significantly more reflux events in the esophagus and the fraction of pH<4 and the RAI were increased up to 10-fold compared to healthy volunteers. In contrast to the esophagus, these differences were not observed in the hypopharynx. Recurrent CRS is often associated with GERD but not with EER. Recurrent disease or prolonged recovery after surgery should raise the suspicion of reflux disease as a possible triggering factor. Because GERD itself cannot be diagnosed by laryngoscopy, and because of the subjectivity of symptoms such as heartburn, the otolaryngologist should consider double-probe pH testing as the diagnostic procedure of choice.  相似文献   
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Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies.  相似文献   
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BACKGROUND: The laboratories of Carmel Medical Centre were located in the main hospital building since its establishment (1977). Due to expansion of the clinical wards, the laboratories were relocated to a nearby building. The project was utilized for reorganization of the laboratories. METHODS: The basic design addressed the existing hospital needs based mainly on the original organization of the laboratories. The project allowed for the prospective organizational changes. The planning, design, and erection were performed by teams of the hospital and by outside parties, headed by the hospital management and the laboratories' director. The laboratories' staff was involved in all phases of the project. RESULTS: The project laid the foundations for future consolidation, i.e., establishment of a central reception station and merging of chemistry, endocrinology, pharmacology, and segments of immunology. The merging involved performance but not validation of tests. Separation between research and routine work was achieved. By-products attained were as follows: simplification of tube handling, reduction in volume of blood needed, improvements in safety, employees' amenities, general atmosphere, and communication within personnel. CONCLUSION: The successful transfer resulted from appropriate design, close cooperation between management and personnel, and the ability to pinpoint problems at early stages with ad hoc solutions.  相似文献   
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BACKGROUND: End-stage renal disease patients have a poor quality of life (QoL), suffer from impaired cognitive functioning, and their electroencephalogram (EEG) shows abnormalities. Conventional haemodialysis (CHD) only partially restores these disorders. Short daily haemodialysis (SDHD) has been reported to improve QoL, but effects on cognitive functioning and EEG have yet to be described. METHODS: Of the 13 patients (11 male, 2 female, age 45.5 +/- 8.1 years), 11 completed the Kidney Disease Quality of Life and Affect Balance Scale questionnaires, 10 underwent neuropsychological testing, and all 13 underwent EEG examination. For the neuropsychological assessments, nine patients (six male, three female, age 45.4 +/- 12.6) who remained on the CHD schedule, served as controls. The dialysis schedule of thrice-a-week for 4 h was changed in the experimental group to six times a week for 2 h (SDHD) over a period of 6 months and back to thrice a week for 4 h. RESULTS: When on SDHD, patients rated several dimensions of health-related QoL as being improved. After resuming CHD, one of these dimensions again decreased and several others worsened even lower than baseline. Cognitive functioning did not change when compared with control data. On the EEG, alpha peak frequency increased slightly when on SDHD but decreased significantly after resuming CHD. CONCLUSIONS: SDHD improves health-related QoL, but has no clear effects on cognitive functioning and EEG. Resumption of CHD after SDHD decreases aspects of QoL and EEG alpha peak frequency but has no effect on cognitive functioning.  相似文献   
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Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
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