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131.
A diagnosis of cyclosporiasis typically involves stool examinations for the presence of Cyclospora oocysts by means of microscopy. In recent years, flow cytometry has been gaining in popularity as a novel method of detecting pathogens in environmental and clinical samples. The present study is an evaluation of a flow cytometric method for the detection and enumeration of Cyclospora oocysts in human fecal specimens associated with food-borne outbreaks of cyclosporiasis in Ontario, Canada. Flow cytometry results were generally very comparable to the original microscopy results for these specimens, in terms of both presence or absence of oocysts and relative oocyst concentrations. Of the 34 fecal specimens confirmed positive for Cyclospora by microscopy, 32 were also found positive by flow cytometry, and 2 others were considered equivocal. Of the eight fecal specimens reported to be negative by microscopy, two were found positive by flow cytometry and five others were considered equivocal. These two flow cytometry-positive samples and one of the equivocal samples were confirmed by microscopic reexamination, suggesting that flow cytometry may be more sensitive than microscopy. While the sample preparation time for flow cytometry is similar to or slightly longer than that for microscopy, the actual analysis time is much shorter. Further, because flow cytometry is largely automated, an analyst's levels of fatigue and expertise will not influence results. Flow cytometry appears to be a useful alternative to microscopy for the screening of large numbers of stool specimens for Cyclospora oocysts, such as in an outbreak situation.  相似文献   
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An epidemiological approach to community assessment is useful for students and practicing nurses. Shamansky and Pesznecker's definition of community is applied to the community assessment process in order to provide an organized framework for data collection, data analysis, and community diagnosis. We applied the framework to an actual community in a case study format.  相似文献   
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ABSTRACT In this paper I aim to explore the dynamics inherent in the assessment process, with particular reference to the therapist's overall emotional response. This response is composed of the therapist's more personal, subjective feelings, as well as their countertransference. Under the pressure exerted by a limited time frame (one interview) and the magnitude of the task, the therapist's contribution to the dynamics will be significant and, I will argue, mutative, affecting the patient's behaviour and thus the direction of the interview. This will have an effect on the assessor's conclusions and recommendation.
The paper describes the therapist's struggle to maintain an observing stance, and to think psychodynamically and diagnostically, when meeting with a stranger at assessment.  相似文献   
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Hepatitis C virus (HCV) is the leading cause of chronic liver disease in the United States. Accurate hepatitis C prevalence estimates are important to guide local public health programs but are usually unavailable to local health jurisdictions. National surveys may not reflect local variation, a particular challenge for urban settings with disproportionately large numbers of residents in high-risk population groups. In 2004, the New York City Department of Health and Mental Hygiene conducted the NYC Health and Nutrition Examination Survey, a population-based household survey of non-institutionalized NYC residents ages 20 and older. Study participants were interviewed and blood specimens were tested for antibody to HCV (anti-HCV); positive participants were re-contacted to ascertain awareness of infection and to provide service referrals. Of 1,786 participants with valid anti-HCV results, 35 were positive for anti-HCV, for a weighted prevalence of 2.2% (95% confidence interval [CI] 1.5% to 3.3%). Anti-HCV prevalence was high among participants with a lifetime history of injection drug use (64.5%, 95% CI 39.2% to 83.7%) or a lifetime history of incarceration as an adult (8.4%, 95% CI 4.3% to 15.7%). There was a strong correlation with age; among participants born between 1945 and 1954, the anti-HCV prevalence was 5.8% (95% CI 3.3% to 10.0%). Of anti-HCV positive participants contacted (51%), 28% (n = 5) first learned of their HCV status from this survey. Continued efforts to prevent new infections in known risk behavior groups are essential, along with expansion of HCV screening and activities to prevent disease progression in people with chronic HCV.  相似文献   
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