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Determining sufficient staff levels and providing quality, economical and efficient service is a problem that is difficult for some staffing managers to solve. The objectives in this paper are to derive a stochastic model for determining the necessary staff levels in various service environments such as hospitals, banks, or in manufacturing settings where the demand for a good staff is erratic. In order to assess the proper staff levels, an equation must be used which involves previous service demand hours that are considered as a distribution integrated within the statistical capability scale distribution. The most important property of this staffing model is that the results are independent of the mix of the jobs, the variation of the in-service time for jobs, and the stationary or nonstationary job arrival rate.  相似文献   
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BACKGROUND: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. METHODS: Twenty-one dogs with naturally occurring congestive heart failure and 21 age-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta and pulmonary artery. RESULTS: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (P < .003), lung (P < .0001), and kidney (P < .02); intimal-medial thickening in the pulmonary artery (P = .04); and fibrosis in the left ventricle (P < .0001) than control dogs. However, they did not have more plaque formation or intimal-medial thickening in the aorta than controls. There was significantly more arterial narrowing in papillary muscles than in all other locations in dogs with congestive heart failure (P < .002). In control dogs, arterial changes were less pronounced and did not differ in different locations. CONCLUSIONS: Dogs with naturally occurring myxomatous mitral valve disease have significantly more arterial changes in the myocardium, lung, and kidney, and significantly more fibrosis in the myocardium than control dogs. This could have important implications in the management of myxomatous mitral valve disease and raises interesting questions about the occurrence and importance of intramural small vessel disease in humans with primary mitral valve prolapse.  相似文献   
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Two cases of painful osteochondritis of the basal epiphysis of the first metatarsal are described. Complete resolution without deformity was achieved in both patients. We suggest that this condition be considered in the differential diagnosis of transitory foot pain in childhood.  相似文献   
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Bile-tolerant Helicobacter species such as Helicobacter pullorum, Helicobacter bilis, and Helicobacter hepaticus are associated with hepatic disorders in animals and may be involved in the pathogenesis of chronic liver diseases (CLD) in humans. Antibody responses to cell surface proteins of H. pullorum, H. bilis, and H. hepaticus in serum samples from patients with CLD, a randomized population group, and healthy blood donors were evaluated by using enzyme linked immunosorbent assay (ELISA). The results were compared with the antibody responses to Helicobacter pylori. For analysis of a possible cross-reactivity between bile-tolerant Helicobacter species and H. pylori, sera from a subpopulation of each group were absorbed with a whole-cell extract of H. pylori and retested by ELISA. Results before absorption showed that the mean value of the ELISA units for H. pullorum was significantly higher in patients with CLD than in healthy blood donors (P = 0.01). Antibody reactivity to cell surface protein of H. hepaticus was also significantly higher in the CLD patients than in the healthy blood donors and the population group (P = 0.005 and P = 0.002, respectively). Following the absorption, antibody responses to H. pullorum decreased significantly in all three groups (P = 0.0001 for CLD patients, P = 0.0005 for the population group, and P < 0.0001 for the blood donors), indicating that cross-reactivity between H. pylori and other Helicobacter spp. occurs. The antibody responses to H. hepaticus and H. bilis in CLD patients remained high following absorption experiments compared to ELISA results before absorption. The significance of this finding requires further investigations.  相似文献   
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106 enterotoxigenicEscherichia coli strains from children and adults from many parts of the world were serotyped for O and H antigens. Some OH types,i.e. O6H16, O8H9, O15H11, O25H42, O78H11 and O78H12, were found repeatedly from different geographical locations. Some of these OH serotypes were only found rarely among more than 20000E. coli strains collected over many years from different locations and sources. It is suggested that these special OH serotypes represent clones which have been selected to the special conditions in the small intestine and selected to carry the plasmids necessary to provoke diarrhoea.  相似文献   
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The complexity and increasing burden of zoonotic diseases create challenges for the health systems of developing nations. Public health systems must therefore be prepared to face existing and future disease threats at the human–animal interface. The key for this is coordinated action between the human and the animal health systems. Although some studies deal with the question of how these two systems interact during unforeseen circumstances such as outbreaks, a dearth of literature exists on how these systems interact on early detection, prevention and control of zoonotic diseases; assessing this problem from the health system perspective in a developing nation adds further complexity. Systems thinking is one of the promising approaches in understanding the factors that influence the system’s complexity and dynamics of health maintenance. Therefore, this study aims to understand the generic structure and complexity of interaction between these actors within the domain of One Health for the effectual prevention and control of zoonotic diseases in India.The present study will be executed in Ahmedabad, located on the Western part of India, in Gujarat state, using a mixed methods approach. For the first step, zoonotic diseases will be prioritised for the local context through semi-quantitative tools. Secondly, utilising semi-structured interviews, stakeholders from the human and animal health systems will be identified and ranked. Thirdly, the identified stakeholders will be questioned regarding the current strength of interactions at various levels of the health system (i.e. managerial, provider and community level) through a quantitative network survey. Fourthly, utilising a vignette method, the ideal convergence strategies will be documented and validated through policy Delphi techniques. Finally, through a participatory workshop, the factors that influence convergence for the control and prevention of zoonotic diseases will be captured.This study will provide a comprehensive picture of the current strength of collaboration and network depth at various levels of the health system. Further, it will assist different actors in identifying the relevance of possible One Health entry points for participation, i.e. it will not only contribute but will also develop a system convergence model for the effectual prevention and control of zoonotic diseases.  相似文献   
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