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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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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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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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To identify the most rapid and reliable technique for recovery and identification of Staphylococcus aureus small-colony variants (SCVs), the colonial appearance of 106 isolates representing SCVs and the normal phenotype were evaluated on two newly described chromogenic agar media. Although almost all of the SCVs grew on the chromogenic agar media, they did not exhibit a change of color. In comparison with conventional media, S. aureus ID agar (SAID; bioMerieux, La Balme Les Grottes, France) showed the most reliable results, with 49 of 53 SCVs tested growing either as an SCV colony or with a normal phenotype after only 24 h of incubation. Growth of SCVs was often not detected before 72 h of incubation on some of the media tested. In conclusion, the most accurate and rapid method to detect both the species S. aureus and the SCV phenotype is to inoculate specimens onto both Columbia blood agar and SAID.  相似文献   
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To investigate radiosensitization by halogenated pyrimidines in human cells, SW-1573 lung tumor cells were grown in absence or presence of 4 mu M of iododeoxyuridine (IdUrd). Cell survival after irradiation with gamma-rays from a Cs-137 source with single doses up to 8 Gy, was determined by clonogenic assay, Radiosensitization by IdUrd was observed in both exponentially growing and plateau phase cells. Linear-quadratic analyses of the radiation survival curves demonstrated that radiosensitization was mainly expressed by an increase of the value of alpha (determining the initial slope of the survival curve) which can be interpreted as an enhancement of fixation of potentially lethal damage (PLD). The value of beta (determining the curvature of the survival curve), which might be attributed to enhanced interaction or to fixation of sublethal damage (SLD), was not influenced. In view of clinical applications of IdUrd it is of interest that radiosensitization has its main effect in the low dose region of the cell survival curve, described by the linear term alpha D.  相似文献   
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Results from baseline and follow-up surveys of the Basic Health Services Program in Kabarole District, Western Uganda carried out in 1989 and 1991 are presented. Indicators in relation to management capability, infrastructure, levels of basic knowledge and skills of health staff, community involvement and utilization of health services were measured. Subjectivity of the data collection was minimized through use of a randomized study design, and external supervision. Comparability of results between the two surveys was assured by employing the same rapid assessment methodology, using a fixed set of indicators. The results suggest a marked improvement of the health services in Kabarole district since implementation of specific project activities and in direct response to action taken following review of information from the original survey work. Overall, it is felt that this particular method of project monitoring, and using the specific method, Systems' Analysis, generates data particularly useful to national governments and other health organizations.  相似文献   
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