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Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students. 相似文献
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Murtaugh LC Stanger BZ Kwan KM Melton DA 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(25):14920-14925
Multiple cell types of the pancreas appear asynchronously during embryogenesis, which requires that pancreatic progenitor cell potential changes over time. Loss-of-function studies have shown that Notch signaling modulates the differentiation of these progenitors, but it remains unclear how and when the Notch pathway acts. We established a modular transgenic system to heritably activate mouse Notch1 in multiple types of progenitors and differentiated cells. We find that misexpression of activated Notch in Pdx1-expressing progenitor cells prevents differentiation of both exocrine and endocrine lineages. Progenitors remain trapped in an undifferentiated state even if Notch activation occurs long after the pancreas has been specified. Furthermore, endocrine differentiation is associated with escape from this activity, because Ngn3-expressing endocrine precursors are susceptible to Notch inhibition, whereas fully differentiated endocrine cells are resistant. 相似文献
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Lactitol and lactulose for the treatment of subclinical hepatic encephalopathy in cirrhotic patients. A randomised, cross-over study 总被引:2,自引:0,他引:2
Fourteen patients with cirrhosis and subclinical hepatic encephalopathy were randomised to treatment with lactitol or lactulose for a 2-month period during which they were monitored clinically, by electroencephalography and by manually administered and computer-based psychometric testing. Following a washout period of 4-6 weeks patients were crossed-over to treatment with the alternative sugar for a similar period of monitoring. None of the patients showed evidence of overt hepatic encephalopathy and only one showed slowing of the electroencephalogram mean cycle frequency at the onset of the trial. However, significant impairment was observed in the group as a whole in the performance of all three manually administered psychometric tests and in four of the ten computer-based test variables. No changes were observed in clinical status or in electroencephalogram mean cycle frequency during treatment with either lactitol or lactulose. However, psychometric performance improved consistently, and to the same degree, during treatment with both sugars. Patients required a mean of 26 g (range 8-36) of lactitol and 25 ml (10-60) of lactulose to achieve two semi-soft stools per day. The majority of patients complained of flatulence during treatment with both sugars but this tended to resolve with continued treatment. Diarrhoea developed in a small number of patients during both treatment periods but this was invariably dose-related. Patients were equally divided in their preference for the two sugars. Patients with subclinical hepatic encephalopathy benefit from treatment with lactitol and lactulose in terms of their psychometric performance. The feasibility and benefits of long-term treatment for this condition need to be elucidated. 相似文献
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Jennifer Stanger Kelley Zwicker Susan Albersheim James J. Murphy III 《Journal of pediatric surgery》2014
Background
Human milk fortifier (HMF) is used in neonatal units throughout North America to facilitate growth of preterm infants. Little data is available on the gastrointestinal side effects and potential adverse events. The purpose of this paper was to present a series of infants presenting with bowel obstruction associated with HMF.Methods
Cases of HMF obstruction were collected between January 2010 and December 2012. Charts were reviewed and relevant data was collected.Results
During the study period, 7 premature infants presented with bowel obstruction secondary to intestinal concretions of HMF. All babies were premature with gestational ages from 25 to 27 weeks. Birth weight was less than 1000 grams in all patients. Patients presented with feeding intolerance, bilious aspirates, abdominal distension, and obstipation. Four of the patients presented with acute deterioration and required urgent surgical intervention.Conclusions
HMF is an important source of nutritional support in infants, which is felt to be safe. We present a series of infants where its use has resulted in significant complications. HMF should be used with caution in infants, especially those with a history of necrotizing enterocolitis. Further research should examine the calcium, protein, and fatty acid concentration tolerable in the gastrointestinal tract of infants. 相似文献9.
Nicholas Stanger Lisa Whitaker Susan H. Backhouse 《Scandinavian journal of medicine & science in sports》2020,30(8):1529-1543
Although research investigating doping in sport is burgeoning, there is still a lack of proxy measures of doping behavior that have undergone extensive psychometric testing. To address this issue, we modified a previously used measure of doping willingness in sport and tested aspects of validity and reliability across four studies. In Study 1, we provided support for the face and content validity of the items, and then found support for the factor structure of the scale in a sample of athletes (N = 205) using confirmatory factor analysis. In Study 2, we collected data from an independent sample of athletes (N = 236) to provide further evidence for the factor structure of the scale using confirmatory factor analysis as well as provided evidence for concurrent and discriminant validity. In Study 3, a further independent sample of athletes (N = 144) completed the scale and provided support for discriminant and predictive validity of the scale. In Study 4, we collected data from a further independent sample (N = 74) to provide support for the test-retest reliability, and stability of items. Lastly, a confirmatory factor analysis was conducted on the samples across Studies 3 and 4, and the composite sample across all four studies which provided further support for the factor structure of the final 8-item scale. Taken together, these findings provide psychometric support for the scale to be used to measure the willingness of athletes to use banned substances to help facilitate future research investigating doping in sport. 相似文献
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目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。
方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。
结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。
结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。 相似文献