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We measured thiamin status in 137 incarcerated and 42 nonincarcerated adolescent males by use of both dietary intake data and a standard biochemical assay, thiamin pyrophosphate (TPP) response. Average thiamin intake of the total group was greater than 120% of the age-specific recommended dietary allowance (RDA). Ninety-two percent of incarcerated subjects and 93% of nonincarcerated subjects were consuming greater than or equal to 70% of RDA. Although average daily thiamin intake of nonincarcerated subjects was significantly higher than that of incarcerated subjects, both groups appeared to be at minimal risk for marginal thiamin status. Comparison of TPP response values indicated that there was no significant difference between groups. However, approximately 24% of the total population appeared to have less than adequate RBC thiamin on the basis of current standards for TPP response. Neither dietary intake nor reported previous alcohol intake was correlated with TPP response. These discrepant findings raise questions about the usefulness of the TPP response as the sole indicator of marginal thiamin status.  相似文献   
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Objectives:  Among children with cerebrospinal fluid (CSF) pleocytosis, the task of separating aseptic from bacterial meningitis is hampered when the CSF Gram stain result is unavailable, delayed, or negative. In this study, the authors derive and validate a clinical decision rule for use in this setting.
Methods:  This was a review of peripheral blood and CSF test results from 78 children (<19 years) presenting to Children's Hospital Columbus from 1998 to 2002. For those with a CSF leukocyte count of >7/μL, a rule was created for separating bacterial from viral meningitis that was based on routine laboratory tests, but excluded Gram stain. The rule was validated in 158 subjects seen at the same site (Columbus, 2002–2004) and in 871 subjects selected from a separate site (Boston, 1993–1999).
Results:  One point each (maximum, 6 points) was assigned for leukocytes >597/μL, neutrophils >74%, glucose <38 mg/dL, and protein >97 mg/dL in CSF and for leukocytes >17,000/mL and bands to neutrophils >11% in peripheral blood. Areas under receiver-operator-characteristic curves (AROCs) for the resultant score were 0.98 for the derivation set and 0.90 and 0.97, respectively, for validation sets from Columbus and Boston. Sensitivity and specificity pairs for the Boston data set were 100 and 44%, respectively, at a score of 0 and 97 and 81% at a score of 1. Likelihood ratios (LRs) increased from 0 at a score of 0 to 40 at a score of ≥4.
Conclusions:  Among children with CSF pleocytosis, a prediction score based on common tests of CSF and peripheral blood and intended for children with unavailable, negative, or delayed CSF Gram stain results has value for diagnosing bacterial meningitis.  相似文献   
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Semi-structured interviews were conducted with a cohort of 22 test applicants who requested Huntington's disease (HD) predictive testing in South Wales, and a random sample of 32 non-requesters, drawn from the South Wales HD register. Apart from identifying differences between the groups, the study afforded the opportunity to listen, at length, to at-risk individuals' accounts of living at risk and their thoughts about predictive testing and genetic services. Emergent themes included difficulties in family communication and the uncertainties inherent in being at risk and undergoing testing. Important factors in decision making about testing were: moral imperatives to clarify one's genetic status; views about the controllability of the future; family attitudes and norms; and the impact of a test result on family members. At-risk individuals' perceptions of the genetics service were that contact with the service would result in pressure to be tested and a need for test applicants to present a favourable view of coping capacities to secure testing. In addition, there was an expectation of ongoing contact with HD families at the initiative of the service providers. Implications of the findings for the way in which predictive testing services are structured and introduced to the at-risk population are discussed.  相似文献   
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The Stafford outbreak of Legionnaires' disease   总被引:1,自引:0,他引:1  
A large outbreak of Legionnaires' disease was associated with Stafford District General Hospital. A total of 68 confirmed cases was treated in hospital and 22 of these patients died. A further 35 patients, 14 of whom were treated at home, were suspected cases of Legionnaires' disease. All these patients had visited the hospital during April 1985. Epidemiological investigations demonstrated that there had been a high risk of acquiring the disease in the out patient department (OPD), but no risk in other parts of the hospital. The epidemic strain of Legionella pneumophila, serogroup 1, subgroup Pontiac 1a was isolated from the cooling water system of one of the air conditioning plants. This plant served several departments of the hospital including the OPD. The water in the cooling tower and a chiller unit which cooled the air entering the OPD were contaminated with legionellae. Bacteriological and engineering investigations showed how the chiller unit could have been contaminated and how an aerosol containing legionellae could have been generated in the U-trap below the chiller unit. These results, together with the epidemiological evidence, suggest that the chiller unit was most likely to have been the major source of the outbreak. Nearly one third of hospital staff had legionella antibodies. These staff were likely to have worked in areas of the hospital ventilated by the contaminated air conditioning plant, but not necessarily the OPD. There was evidence that a small proportion of these staff had a mild legionellosis and that these 'influenza-like' illnesses had been spread over a 5-month period. A possible explanation of this finding is that small amounts of aerosol from cooling tower sources could have entered the air-intake and been distributed throughout the areas of the hospital served by this ventilation system. Legionellae, subsequently found to be of the epidemic strain, had been found in the cooling tower pond in November 1984 and thus it is possible that staff were exposed to low doses of contaminated aerosol over several months. Control measures are described, but it was later apparent that the outbreak had ended before these interventions were introduced. The investigations revealed faults in the design of the ventilation system.  相似文献   
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