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81.
Megan L. Clayton Katherine Clegg Smith Roni A. Neff Keshia M. Pollack Margaret Ensminger 《International journal of occupational and environmental health》2015,21(4):314-327
Background
Foodborne disease is a significant problem worldwide. Research exploring sources of outbreaks indicates a pronounced role for food workers'' improper health and hygiene practice.Objective
To investigate food workers'' perceptions of factors that impact proper food safety practice.Method
Interviews with food service workers in Baltimore, MD, USA discussing food safety practices and factors that impact implementation in the workplace. A social ecological model organizes multiple levels of influence on health and hygiene behavior.Results
Issues raised by interviewees include factors across the five levels of the social ecological model, and confirm findings from previous work. Interviews also reveal many factors not highlighted in prior work, including issues with food service policies and procedures, working conditions (e.g., pay and benefits), community resources, and state and federal policies.Conclusion
Food safety interventions should adopt an ecological orientation that accounts for factors at multiple levels, including workers'' social and structural context, that impact food safety practice. 相似文献82.
NMR‐based approach to the analysis of radiopharmaceuticals: radiochemical purity,specific activity,and radioactive concentration values by proton and tritium NMR spectroscopy
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David J. Schenk Peter G. Dormer David Hesk Scott R. Pollack Carolee Flader Lavey 《Journal of labelled compounds & radiopharmaceuticals》2015,58(7):291-298
Compounds containing tritium are widely used across the drug discovery and development landscape. These materials are widely utilized because they can be efficiently synthesized and produced at high specific activity. Results from internally calibrated 3H and 1H nuclear magnetic resonance (NMR) spectroscopy suggests that at least in some cases, this calibrated approach could supplement or potentially replace radio‐high‐performance liquid chromatography for radiochemical purity, dilution and scintillation counting for the measurement of radioactivity per volume, and liquid chromatography/mass spectrometry analysis for the determination of specific activity. In summary, the NMR‐derived values agreed with those from the standard approaches to within 1% to 9% for solution count and specific activity. Additionally, the NMR‐derived values for radiochemical purity deviated by less than 5%. A benefit of this method is that these values may be calculated at the same time that 3H NMR analysis provides the location and distribution of tritium atoms within the molecule. Presented and discussed here is the application of this method, advantages and disadvantages of the approach, and a rationale for utilizing internally calibrated 1H and 3H NMR spectroscopy for specific activity, radioactive concentration, and radiochemical purity whenever acquiring 3H NMR for tritium location. 相似文献
83.
Hematopoietic stem cell donor registry strategies for assigning search determinants and matching relationships 总被引:4,自引:0,他引:4
Hurley CK Setterholm M Lau M Pollack MS Noreen H Howard A Fernandez-Vina M Kukuruga D Müller CR Venance M Wade JA Oudshoorn M Raffoux C Enczmann J Wernet P Maiers M 《Bone marrow transplantation》2004,33(4):443-450
Registries and cord blood banks around the world collect and store the HLA types of volunteers in order to identify matched unrelated donors for patients requiring hematopoietic stem cell transplantation. This task is complicated by the many formats in which HLA types are provided by the testing laboratories (types obtained by serology vs by DNA-based methods; high vs intermediate vs low resolution) and by the need to identify which of these diverse types are most likely to match the HLA assignments of a searching patient as closely as possible. Conversion of the assignments to 'search determinants' may be included within the algorithm used to select and prioritize a list of potentially suitable donors, either as an aid to matching or as a tool to optimize the performance of comparisons within large data files. The strategies used by registries to create search determinants are described. A set of search determinants, utilized by the National Marrow Donor Program, is provided as an example and is intended to initiate further discussion aimed at understanding the process used by each registry with the possibility of developing a standard process among registries worldwide. 相似文献
84.
Antibody against tuberlin: the specific visualization of cytoplasmic microtubules in tissue culture cells. 总被引:24,自引:11,他引:24
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K Weber R Pollack T Bibring 《Proceedings of the National Academy of Sciences of the United States of America》1975,72(2):459-463
Cytoplasmic microtubules in tissue culture cells can be directly visualized by immunofluorescence microscopy. Antibody against tubulin from the outer doublets of sea urchin sperm flagella decorates a network of fine cytoplasmic fibers in a variety of cell lines of human, monkey, rat, mouse, and chicken origin. These fibers are separate and of uniform thickness and are seen throughout the cytoplasm. The fibers disappear either in a medium containing colchicine or after subjection of the cells to low temperature. The same treatments do not destroy the microfilamentous structures that are visualized by means of antibody against actin. When tryspin-treated enucleated cells are replated and then stained with antibody against tubulin, the fibers can be seen to traverse the entire enucleated cytoplasm. 相似文献
85.
Neisseria subflava is a rare cause of bacterial endocarditis. Only seven cases have been identified in the world literature if strict criteria as to organism classification and of endocarditis are applied to individual case reports. The first reported case in an intravenous drug user is described. In addition, findings on serial two-dimensional and M-mode echocardiography performed during and after the treatment period are presented. This patient's recovery with anti-microbial therapy alone despite evidence of aortic and significant mitral valve involvement is in accord with results of other antibiotic-treated cases. 相似文献
86.
The publication of comprehensive evidence-based guidelines for the management of non-ST-segment elevation acute coronary syndrome by the American College of Cardiology and the American Heart Association in September 2000 marked a sentinel event in the evolution of managing this challenging patient population. Many of the recommendations included in the guidelines have relevance to the emergency department care of patients with non-ST-segment elevation acute coronary syndrome and were summarized in Annals of Emergency Medicine in September 2001. New clinical data in this area continue to accumulate at a remarkably rapid rate, prompting the American College of Cardiology and the American Heart Association to publish an update of the 2000 guidelines in October 2002. Several of the modified and new recommendations again potentially affect ED management. These are presented and discussed here. 相似文献
87.
Body fat content and 25-hydroxyvitamin D levels in healthy women 总被引:15,自引:0,他引:15
Arunabh S Pollack S Yeh J Aloia JF 《The Journal of clinical endocrinology and metabolism》2003,88(1):157-161
Obesity is associated with alterations in the vitamin D endocrine system. Lower levels of serum 25-hydroxyvitamin D (25-OHD) in morbidly obese individuals may be secondary to an alteration in tissue distribution resulting from an increase in adipose mass. Therefore, morbidly obese individuals are expected to need higher doses of vitamin D supplementation than the general population. However, it is still unknown whether adiposity (or percentage body fat) should be taken into consideration while assessing vitamin D requirements in the general population. To study the relationship between 25-OHD levels and percentage body fat content in healthy women, we studied 410 healthy women between 20 and 80 yr of age with body mass index ranging from 17 to 30 kg/m2. We analyzed the correlation between serum 25-OHD level and percentage body fat measured by dual energy x-ray absorptiometry. We also analyzed the influence of season, dietary vitamin D intake, age, and race on this relationship. The levels of serum 25-OHD inversely correlated with percentage body fat. The correlation was -0.13 (P = 0.013) after adjusting for race, age, season, and dietary vitamin D intake. In a multiple stepwise regression, race and season were found to have a major influence on serum 25-OHD (cumulative R2 = 0.34), and percentage body fat, although modest (additional R2 = 0.02), also had an independent statistically significant influence on serum 25-OHD levels. We conclude, percentage body fat content is inversely related to the serum 25-OHD levels in healthy women. 相似文献
88.
89.
Microarray analysis reveals a major direct role of DNA copy number alteration in the transcriptional program of human breast tumors 总被引:33,自引:0,他引:33
Pollack JR Sørlie T Perou CM Rees CA Jeffrey SS Lonning PE Tibshirani R Botstein D Børresen-Dale AL Brown PO 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(20):12963-12968
Genomic DNA copy number alterations are key genetic events in the development and progression of human cancers. Here we report a genome-wide microarray comparative genomic hybridization (array CGH) analysis of DNA copy number variation in a series of primary human breast tumors. We have profiled DNA copy number alteration across 6,691 mapped human genes, in 44 predominantly advanced, primary breast tumors and 10 breast cancer cell lines. While the overall patterns of DNA amplification and deletion corroborate previous cytogenetic studies, the high-resolution (gene-by-gene) mapping of amplicon boundaries and the quantitative analysis of amplicon shape provide significant improvement in the localization of candidate oncogenes. Parallel microarray measurements of mRNA levels reveal the remarkable degree to which variation in gene copy number contributes to variation in gene expression in tumor cells. Specifically, we find that 62% of highly amplified genes show moderately or highly elevated expression, that DNA copy number influences gene expression across a wide range of DNA copy number alterations (deletion, low-, mid- and high-level amplification), that on average, a 2-fold change in DNA copy number is associated with a corresponding 1.5-fold change in mRNA levels, and that overall, at least 12% of all the variation in gene expression among the breast tumors is directly attributable to underlying variation in gene copy number. These findings provide evidence that widespread DNA copy number alteration can lead directly to global deregulation of gene expression, which may contribute to the development or progression of cancer. 相似文献
90.