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排序方式: 共有4508条查询结果,搜索用时 31 毫秒
71.
DJ MacGowan MN Janal WC Clark RN Wharton RM Lazar RL Sacco JP Mohr 《Canadian Metallurgical Quarterly》1997,49(1):120-125
BACKGROUND: Questionnaire-based surveys from several countries have consistently detected adverse health associated with home dampness and mould growth. METHODS: To test the validity of questions commonly used to indicate the presence of indoor mould, questionnaires were administered in 403 homes where dust samples were taken for viable fungi and air samples for ergosterol. RESULTS: Geometric mean concentrations of the total viable fungi were 255 (SE 116) x 10(3) CFU/g when mouldy odours were reported and 155 (SE 55) when odours were not reported (P = 0.01). Similarly, reported water damage was associated with a 50% increase (P = 0.06). Geometric mean concentrations of the predominantly indoor-source fungi, Aspergillus plus Penicillium, were twice as high when mould or mildew was reported than when not mentioned (P = 0.01). The presence of reported mould or water damage was unrelated to the presence of detectable levels of ergosterol. There was evidence for reporting bias: in the presence of low concentrations of viable fungi in dust, respondents reporting allergies were more likely to report visible mould growth (odds ratio [OR] = 1.8, 95% confidence interval [CI]: 0.9-3.5, P = 0.10. In the presence of elevated concentrations of dust fungi, respondents who smoked were less likely to report visible mould growth, (OR = 0.4, 95% CI: 0.2-0.7, P = 0.005). CONCLUSIONS: Reported mould, water damage, and mouldy odours were associated with elevated levels of indoor fungi. However, inaccuracy was high and there was evidence of a systematic reporting bias. Future research should concentrate on developing accurate objective measures of exposure to fungi, and then use this information to develop valid questionnaires. Currently, objective measures not questionnaires, are recommended to clarify the health effects of indoor fungi. 相似文献
72.
73.
BACKGROUND: Australia has a high rate of cardiovascular disease mortality and also a significant proportion of migrants. Little is known about the morbidity experience or cardiovascular risk factors among the larger migrant groups, and this is especially true of the Arabic-speaking population. OBJECTIVES: The objectives of the study were to identify the health profile of Arabic-speaking people in Sydney, Australia, to explore the relationship between level of acculturation and health indicators and to identify the morbidity profile of patients presenting to Arabic-speaking general practitioners (GPs). DESIGN: Adult Arabic-speaking patients aged 18-70 years attending 20 Arabic-speaking GPs in Canterbury, Sydney, during the 2-week study period were asked to complete a self-administered questionnaire in Arabic or English while waiting to see the GP. Data on cardiovascular risk factors, level of acculturation and reasons for seeing the GP were collected. RESULTS: Data were collected from 851 patients (62% response rate). Almost three-quarters (73%) of males and 36% of females were considered overweight or obese (body mass index > 25). Of concern, 37% of males and 28% of females were smokers. Females were significantly less likely to have been tested for diabetes (p < .05) or raised blood pressure (p < 0.05) compared with females in NSW. Respondents consumed less bread per day and more fruits than in NSW overall. Respiratory complaints (flu and colds) were the most frequently reported reasons for patient encounters. Except for the youngest age group, males gave more reasons for encounters than females. CONCLUSIONS: Consecutive sampling of ethnic patients attending a GP who speaks their language holds promise as a method of needs assessment with migrant populations. Further, our results suggest that smoking and weight reduction programs are priorities in the Arabic-speaking community. These risk factors are ideal for intervention by GPs speaking the same language. 相似文献
74.
In rats, the phosphorothionate insecticide parathion exhibits greater toxicity than chlorpyrifos, while in catfish the toxicities are reversed. The in vitro inhibition of brain acetylcholinesterase (AChE) by the active metabolites of the insecticides and the rates at which these inhibitor-enzyme complexes undergo reactivation/ aging were investigated in both species. Rat AChE was more sensitive to inhibition than catfish AChE as demonstrated by greater bimolecular rate constants (ki) in rats than in catfish. In both species, chlorpyrifos-oxon yielded higher ki's than paraoxon. The higher association constant (KA) of chlorpyrifos-oxon than paraoxon in both species and the lack of significant differences in the phosphorylation constants (kp) suggest that association of the inhibitor with AChE is the principal factor in the different potencies between these two inhibitors. In catfish, the ki of chlorpyrifos-oxon was 22-fold greater than that of paraoxon, while in rats it was 9-fold greater, suggesting that target site sensitivity is an important factor in the higher toxicity of chlorpyrifos to catfish but not in the higher toxicity of parathion to rats. No spontaneous reactivation of phosphorylated catfish AChE occurred and there were no differences in the first oder aging constants (ka) between compounds. For phosphorylated rat AChE, there were no differences in the first order reactivation constants (kr) but the ka for chlorpyrifos-oxon was significantly greater than that for paraoxon. This difference suggests that the steric positioning of the diethyl phosphate in the esteratic site is not the same between the two compounds, leading to differences in aging. 相似文献
75.
M Albert C Athanassopoulos LB Auerbach D Bauer R Bolton B Boyd RL Burman I Cohen DO Caldwell BD Dieterle JB Donahue AM Eisner A Fazely FJ Federspiel GT Garvey RM Gunasingha V Highland J Hill R Imlay K Johnston WC Louis A Lu AK Mann J Margulies K McIlhany W Metcalf RA Reeder V Sandberg M Schillaci D Smith I Stancu W Strossman MK Sullivan GJ VanDalen W Vernon YX Wang DH White D Whitehouse D Works Y Xiao S Yellin 《Canadian Metallurgical Quarterly》1995,51(3):R1065-R1069
76.
77.
The biological consequences of O6-methylguanine (m6G) in DNA are well recognized. When template m6G is encountered by DNA polymerases, replication is hindered and trans-lesion replication results in the preferential incorporation of dTMP opposite template m6G. Thus, unrepaired m6G in DNA is both cytotoxic and mutagenic. Yet, cell lines tolerant to m6G in DNA have been isolated, which indicates that some cellular DNA polymerases may replicate m6G-containing DNA with reasonable efficiency. Previous reports suggested that mammalian pol beta could not replicate m6G-containing DNA, but we find that pol beta can catalyze trans-lesion replication; however, the lesion must reside in the optimal context for pol beta activity, single- or short nucleotide gapped substrates. Primed single-stranded DNA templates, with or without template m6G, were poor substrates for pol beta as reported in earlier studies. In contrast, trans-lesion replication by bacteriophage T4 DNA polymerase was observed for primed single-stranded DNA templates. Replication of m6G-containing DNA by T4 DNA polymerase required the gp45 accessory protein that clamps the polymerase to the DNA template. The rate-limiting step in replicating m6G-containing DNAs by both DNA polymerases tested was incorporation of dTMP across from the lesion. 相似文献
78.
ED Pisano R McLelland RL Clark K Dicke K Muller 《Canadian Metallurgical Quarterly》1993,28(8):762-766
RATIONAL AND OBJECTIVES: Training in breast imaging is highly variable among radiology programs. The authors have developed a standardized breast imaging curriculum for radiology residents. METHODS: This curriculum has been implemented within the residency program at the University of North Carolina at Chapel Hill. It includes nine standardized components: 1) the clinical activities of the service; 2) the study of breast imaging teaching file films and contribution of new cases; 3) selected readings; 4) formal discussion with faculty on the readings; 5) review of this material using an interactive computer program; 6) formal conferences; 7) technical and quality control activities; 8) research activities; and 9) an evaluation. The participating residents have been surveyed regarding their opinions of their educational experience. RESULTS AND CONCLUSION: The standardized curriculum has been well received by the participating residents. Conclusions about the educational efficacy of such a curriculum cannot be made until more residents have used it. 相似文献
79.
RL Simpson 《Canadian Metallurgical Quarterly》1997,28(7):17-18
Nurses now have a central place to check standards and evaluate systems. The Nursing Information and Data Set Evaluation Center develops, disseminates and evaluates nursing practice sets used by vendors. This center, established by the American Nurses Association, ensures that interventions and outcomes related to nursing diagnosis are appropriate and accurate. 相似文献
80.
Large scale use of lysozyme for periplasmic release has been impeded by the cost of the pure enzyme and its subsequent presence as a contaminant in later downstream processing steps. In this paper, we discuss the use of lysozyme for pilot scale recovery of a periplasmic enzyme from E. coli. The effects of concentration of sucrose, lysozyme and cells on periplasmic enzyme release were examined. Lysozyme concentration can be reduced 5-fold from previous reports and a reduction in sucrose concentration from 20 to 15% (w/v) allows an improvement in centrifugal harvesting by reducing viscosity. High levels of release were still achieved using this technique and further improvements in yield were obtained by optimising other components of the releasing mixture. Results show that some release is still achieved in circumstances where no lysozyme use is possible. Results also indicate that a substantial proportion (up to 70%) of lysozyme remains bound to the cellular debris after its action and is removed with this material. 相似文献