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To better understand the potential environmental health risk presented by West Nile virus (WNV)-contaminated feces, we quantified the amount of WNV present in the feces of experimentally infected American crows (Corvus brachyrhynchos) and fish crows (Corvus ossifragus). Peak fecal titers ranged from 10(3.5) to 10(8.8) plaque-forming units (PFU)/g for 10 American crows and from 10(2.3) to 10(6.4) PFU/g for 10 fish crows. The presence of infectious WNV in bird feces indicates a potential for direct transmission of WNV. Thus, handlers of sick or dead birds should take appropriate precautions to avoid exposure to fecal material.  相似文献   
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The Neuro-Bambi     
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Over a period of years the ventilation system of a community hospital progressively deteriorated until it no longer met regulatory guidelines. The hospital, a publicly funded military facility, requested funding to repair the ventilation system, but funds were not forthcoming because of budget austerity. When an increase in infections was documented, high-risk operations were curtailed and funding was expedited. With the new improved ventilation system the operating rooms once again met regulatory guidelines and infections returned to baseline rates. Throughout the period infections remained below recognized national levels.  相似文献   
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Introduction     
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Metastases of differentiated thyroid cancer may show different uptake patterns for fluorine-18 fluorodeoxyglucose and [131I]NaI. FDG positron emission tomography (PET), iodine-131 whole-body scintigraphy (131I WBS) and magnetic resonance imaging were performed in 58 unselected patients, and spiral computed tomography (CT) of the lung in 25 patients. Thirty-eight patients presented with papillary carcinomas, 15 patients with follicular carcinomas and five patients with variants of follicular carcinoma. Primary tumour stage (pT) was pT1 in 3, pT2 in 19, pT3 in 11 and pT4 in 25 cases. For the detection of metastases, FDG PET was found to have a sensitivity of 50%, 131I WBS a sensitivity of 61%, and the two methods combined a sensitivity of 86%. When FDG PET was limited to patients with elevated thyroglobulin (Tg) levels and negative 131I WBS, the sensitivity of this algorithm was 82%. Of the 21 patients with lymph node metastases, seven presented with FDG uptake but no iodine uptake. In four of them, a second FDG hot spot appeared in a lymph node metastasis of normal size. Five of the seven patients underwent surgery. None of the eight patients with pulmonary metastases smaller than 1 cm exhibited FDG uptake, while five of them had iodine uptake. All had positive results on spiral CT. In conclusion, FDG PET cannot be substituted for 131I WBS. If the Tg level is elevated and 131I WBS is negative, FDG PET can be used to detect lymph node metastases and complements anatomical imaging. A spiral CT of the lung is useful to exclude pulmonary metastases before planning a dissection of iodine-negative lymph node metastases. Received 2 May and in revised form 8 July 1997  相似文献   
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Epidemiological surveys indicate that the prevalence of epilepsy is higher in developing countries than in industrialized countries. Except for neurocystocercosis due to Taenia solium, little is known about possible underlying causes. This article reports the relationship between epilepsy and onchocerciasis in an Onchocerca volvulus endemic area in West Uganda. Individuals complaining of seizures were identified by means of a population census in 12 villages. Active epilepsy was confirmed in 61 of 4743 inhabitants (crude prevalence rate = 1.3%; age-standardized rate = 1.1%). Distribution of epilepsy in the study area was clustered, ranging from a prevalence of 0.2% to 3.4% in different villages. Age-specific prevalence was highest between 10 and 19 years, with a rate of 3.6% for the study are as a whole, and up to 10.0% in villages of high epilepsy prevalence. The prevalence of onchocerciasis in the 10-19-year-old age group was assessed by skin-snip biopsy and ranged from 15% to 85% in different villages. Epilepsy was significantly more frequent in the three villages with the highest levels of O. volvulus endemicity than in other villages (P < 0.0001). Serological testing for T. solium infection was positive in one and borderline in three of 53 epilepsy patients tested. The significant correlation between epilepsy and onchocerciasis did not change when these four patients were excluded from the analysis. These findings suggest a strong association between epilepsy and onchocerciasis in this area. This could have significant implications for the concept of morbidity due to O. volvulus.  相似文献   
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