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621.
The use of food as a reward for good student behavior or academic performance is discouraged by many national organizations, yet this practice continues to occur in schools. Our multiyear cross-sectional study examined the use of food as a reward in elementary schools and evaluated the association between district policies and school practices. School data were gathered during the 2007-2008, 2008-2009, and 2009-2010 school years via mail-back surveys (N=2,069) from respondents at nationally representative samples of US public elementary schools (1,525 unique schools, 544 of which also participated for a second year). During every year, the corresponding district policy for each school was gathered and coded for provisions pertaining to the use of food as a reward. School practices did not change over time and as of the 2009-2010 school year, respondents in 42.1% and 40.7% of schools, respectively, indicated that food was not used as a reward for academic performance or for good student behavior. In multivariate logistic regression analyses controlling for school characteristics and year, having a district policy that prohibited the use of food as a reward was significantly associated with school respondents reporting that food was not used as a reward for academic performance (P<0.05) or for good student behavior (P<0.05). School-level respondents in the West and the Midwest were less likely to report that food was not used as a reward than were respondents in the South and Northeast. As of 2009-2010, only 11.9% of the districts in our study prohibited the use of food as a reward. Strengthening district policies may reduce the use of food rewards in elementary schools.  相似文献   
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The molecular mechanisms contributing to the tumorigenesis of insulinomas are still poorly understood. As moderate to high rates of LOH have been found on chromosome 22q in gastrinomas, we performed a finer deletion mapping study of chromosome 22q with 8 microsatellite markers in 15 insulinomas (4 malignant and 11 benign). Fourteen of 15 (93%) insulinomas revealed LOH on chromosome 22q, whereas the shortest region of overlap implicated a deletion of approximately 700 kb at 22q12.1-q12.2 with an LOH rate of up to 57% (8 of 14). Although the expressed sequence tag marker A006E25 that is localized in the hSNF5/INI1 gene on 22q11.2 revealed LOH in 50% of informative cases (7 of 14), no alterations in this gene could be identified by single strand conformational polymorphism analysis, direct DNA sequencing, or RNA expression analysis. Remarkably, the four malignant tumors showed a common deleted region between markers D22S345 and D22S1144 compared with none of the 11 benign insulinomas. The observed high frequency of chromosome 22q12 deletions in insulinomas is suggestive for a region compatible with harboring a tumor suppressor gene. The hSNF5/INI1 gene is most likely not the candidate gene, because no alterations could be identified. The distinct pattern of allelic loss identified in this chromosomal region appears to be an attractive candidate marker for further evaluation with regard to the discrimination between benign and malignant insulinomas.  相似文献   
624.
BACKGROUND: The availability of competitive foods in schools is a modifiable factor in efforts to prevent childhood obesity. The Alliance for a Healthier Generation launched the Healthy Schools Program in 2006 to encourage schools to create healthier food environments, including the adoption of nutritional guidelines for competitive beverages and foods. This study examines nationwide awareness and implementation of the guidelines in US public elementary schools. METHODS: Data were collected from a nationally representative sample of elementary schools using mail-back surveys in 2006-2007, 2007-2008, 2008-2009, and 2009-2010. RESULTS: From 2006-2007 to 2009-2010, awareness of the Alliance's beverage guidelines increased from 35.0% to 51.8% among school administrators (p < .01); awareness of the food guidelines increased from 29.4% to 40.2% (p < .01). By 2009-2010, almost one third of the schools that sold competitive beverages and foods reported having implemented or being in the process of implementing the guidelines. Implementation was higher among schools from Southern states. Schools with a majority of Black or Latino students were less likely to implement the guidelines. CONCLUSIONS: Awareness and implementation of the Alliance's beverage and food guidelines has significantly increased since the 2006-2007 school year, indicating successful diffusion of the guidelines. However, many administrators at schools who sold competitive products were not aware of the guidelines, indicating a need for continued efforts. In addition, lower implementation among schools serving minority students suggests that the Alliance's targeted efforts to provide intensive technical assistance to such schools is warranted and necessary.  相似文献   
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