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One of the major challenges when testing drug candidates targeted at a specific pathway in whole animals is the discrimination between specific effects and unwanted, off-target effects. Here we used the zebrafish to define several developmental defects caused by impairment of Egf signaling, a major pathway of interest in tumor biology. We inactivated Egf signaling by genetically blocking Egf expression or using specific inhibitors of the Egf receptor function. We show that the combined occurrence of defects in cartilage formation, disturbance of blood flow in the trunk and a decrease of myelin basic protein expression represent good indicators for impairment of Egf signaling. Finally, we present a classification of known tyrosine kinase inhibitors according to their specificity for the Egf pathway.  相似文献   
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针对传统科研活动环境中信息资源相对孤立、项目成员间协作性差、项目管理和协作过程复杂以及整体效率低下等问题,本文提出基于Web科研协作管理模式,该模式便于科研项目管理,实现科研团体内部知识的高效共享,提高科研协作管理效率,并有效推动科研协作管理信息化进程.  相似文献   
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Background: Research in oral health contributes effectively to decisions and strategies aimed at improving the oral health of populations. Further contributions to enhance current knowledge of oral health in Africa are required. Objectives: The principal objective of this study was to produce an analysis of oral health research published from different subregions of Africa and to estimate bilateral and multilateral international cooperation in oral health research during the period 2005–2010. Methods: The PubMed database was searched for published articles on topics related to oral health in Africa. A total of 935 oral health‐related articles were retrieved during April and May 2011. Results: Publications emanating from Nigeria and South Africa accounted for a striking 68% of all oral health‐related material published from Africa during the study period. Researchers from 30 different countries had participated in collaboration on at least one published article. A total of 262 journals had published at least one item examining oral health in Africa, but only 29 journals had published more than seven articles. These 29 journals accounted for 66% of all published material and induced non‐African reviews (26%) and African reviews (40%). Conclusions: This study shows strong variation among countries in the production of articles on oral health whereby rich countries produce greater quantities of published research and poorer nations more frequently develop research partnerships with other countries.  相似文献   
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目的 探讨抑制血小板内皮细胞黏附因子-1(PECAM-1)表达对多药耐药基因1(MDR-1)及其编码产物P-糖蛋白(P-gp)的影响.方法 设计并化学合成针对PECAM-1的三条siRNA序列,命名为si-PECAM1,2,3,脂质体转染法将其转入CNE1/R,采用Semi-qRT-PCR、Western blot方法检测并筛选出抑制效果最好的si-PECAM序列,将筛选出的si-PECAM转入CNE1/R,采用Semi-qRT-PCR、Western blot方法检测抑制PECAM-1表达前后MDR-1及其编码产物P-gp的变化情况.结果 Semi-qRT-PCR的结果显示,设计三条si-PECAM序列均有效,以si-PECAM3干扰效果最明显(P<0.001),Western blot结果显示与Semi-qRT-PCR的结果一致;转染si-PECAM3 48 h后做Semi-qRT-PCR的结果显示抑制PECAM-1表达后MDR-1表达明显下调(P<0.001),Western blot结果与Semi-qRT-PCR的结果一致,抑制PECAM-1表达后MDR-1编码产物P-gp的表达也明显下调(P<0.001).结论 抑制CNE1/R中PECAM-1表达后MDR-1及其编码产物P-gp的表达均明显下调,提示PECAM-1可能参与X射线辐射诱导人鼻咽癌细胞发生多药耐药.  相似文献   
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A recent study examined the rate of full‐length research paper publication following abstract presentation at the British association of clinical anatomists (BACA) annual meetings. The accepted standard for research dissemination is peer‐reviewed publication following presentation at a national or international meeting. The study objectives were quantitative assessment of the abstracts presented at the American Association of Clinical Anatomists' (AACA) annual meetings with regards to the rate of subsequent full‐length publication and comparison to BACA publication rates. All abstracts presented at the AACA annual meetings between 2003 and 2010 were analysed. MEDLINE was searched to identify peer‐reviewed publications arising from each presented abstract. In total, 1,120 abstracts were presented with 22.9% (n = 257) subsequently published as full‐length research papers. The mean number of abstracts presented each year was 140.0 ± 35.9. The median time to publication was 16 months. Chi‐squared analysis showed the publication rate of abstracts presented at AACA (22.9%) was not statistically significantly different to BACA (20.4%) (P = 0.09). A total of 11.3% (n = 29) of the articles were published as full‐length research articles before presentation as an abstract at an AACA meeting compared to 5.4% of abstracts presented at a BACA meeting. These rates are lower but comparable to those of surgical specialty meetings. Further work should try to identify any concerning reasons for the reduced rate of abstract publication in anatomical research. Clin. Anat. 30:140–144, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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