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Background  

Glioblastoma is one of the deadliest forms of cancer, in part because of its highly invasive nature. The tumor suppressor PTEN is frequently mutated in glioblastoma and is known to contribute to the invasive phenotype. However the downstream events that promote invasion are not fully understood. PTEN loss leads to activation of the atypical protein kinase C, PKCι. We have previously shown that PKCι is required for glioblastoma cell invasion, primarily by enhancing cell motility. Here we have used time-lapse videomicroscopy to more precisely define the role of PKCι in glioblastoma.  相似文献   
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Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor superfamily of proteins. Although initial data illustrated the key role that OPG plays in bone turnover, numerous recent reports indicate that OPG is also an important factor in inflammatory pathways and tumor cell survival. OPG contributes directly to inflammatory processes and has been evaluated as a novel non‐invasive biomarker of gut inflammation. Furthermore, OPG affects cell turn‐over, differentiation, death, and survival via extracellular pathways, correlating with worse prognosis in inflammatory bowel diseases and several gastrointestinal carcinomas. It is now clear that OPG has multiple functions and characteristics. This review gives an overview of OPG, highlights its roles in different extracellular pathways, and outlines how OPG could be used as a novel non‐invasive biological marker in inflammatory bowel diseases and gastrointestinal carcinomas.  相似文献   
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OBJECTIVE: Little is known about the predictors of symptom change or the methods that might increase user 'compliance' on websites designed to improve mental health outcomes. The present paper: (i) examines predictors of expected final depression and anxiety scores on the MoodGYM website as a function of user characteristics; and (ii) compares the compliance rates of the original site with the new public version of the site (MoodGYM Mark II). The latter site requires compulsory completion of 'core' online assessments and may increase completion of site questionnaires. METHOD: MoodGYM Mark I participants were 19,607 visitors (public registrants) between April 2001 and September 2003 plus 182 participants who had been randomly assigned to MoodGYM in an earlier trial (The BlueMood Trial). MoodGYM Mark II participants were 38,791 public registrants of the MoodGYM Mark II site collected between September 2003 and October 2004. Symptom assessments are repeated within the website intervention to allow the examination of change in symptoms. Outcome variables were gender, initial depression severity scores, number of assessments completed and final anxiety and depression scores. RESULTS: Men are predicted to be 0.19 units (SE=0.095) higher than women on depression, controlling for the initial depression level and number of modules completed. For initial depression scores above 2, it is predicted that the final score will indicate improvement relative to the initial score, the magnitude of the improvement increasing as a function of the number of modules attempted. For initial anxiety scores above 2, it is predicted that the final score will indicate improvement relative to the initial score, the magnitude of the improvement increasing as a function of the number of modules attempted. Mark II registrants were more likely than to Mark I registrants to complete onsite assessments. CONCLUSIONS: Visitors to the MoodGYM site are likely to have better psychological outcomes if they complete more of the site material. Compulsory completion of core sections increases assessment completion. There is a need to examine further the significance of attrition from online interventions, to develop methods of handling missing data, and to investigate strategies to improve visitor dropout.  相似文献   
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目的 :研究雷米普利和氯沙坦对动脉粥样硬化 (atherosclerosis,AS)早期形成的影响。方法 :将 4 4只金黄地鼠随机分为 5组 ,分别给常规饲料 (对照组 )、高脂饲料 (含 10 %椰子油和 0 .0 5 %胆固醇 )、高脂饲料加雷米普利 (2mg·kg 1)、高脂饲料加氯沙坦 (10mg·kg 1)和高脂饲料加雷米普利 (2mg·kg 1)与氯沙坦 (10mg·kg 1)处理12周 ,测定血压、血脂、AS斑块面积和肝组织中胆固醇含量的变化。结果 :数据表明雷米普利和氯沙坦不论是单独应用还是联合应用均能有效降低平均动脉压 (P <0 .0 0 1)和肝组织中胆固醇的含量 ,雷米普利能显著降低血浆中甘油三酯的水平 (P <0 .0 5 ) ,结果还显示雷米普利与氯沙坦联合应用能提升血浆中高密度脂蛋白 (P <0 .0 5 ) ,各药物处理组的AS斑块面积有不同程度降低但无统计学意义。结论 :雷米普利与氯沙坦具有一定的抑制AS形成作用 ,其机制可能与降低血压和改变脂代谢有关。  相似文献   
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