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Archive for History of Exact Sciences - We show that Dedekind, in his proof of the principle of definition by mathematical recursion, used implicitly both the concept of an inductive cone from an... 相似文献
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Danielle Kamato Muhamad Ashraf Rostam Rebekah Bernard Terrence J. Piva Nitin Mantri Daniel Guidone Wenhua Zheng Narin Osman Peter J. Little 《Cellular and molecular life sciences : CMLS》2015,72(4):799-808
G protein-coupled receptor (GPCR) signalling is mediated through transactivation-independent signalling pathways or the transactivation of protein tyrosine kinase receptors and the recently reported activation of the serine/threonine kinase receptors, most notably the transforming growth factor-β receptor family. Since the original observation of GPCR transactivation of protein tyrosine kinase receptors, there has been considerable work on the mechanism of transactivation and several pathways are prominent. These pathways include the “triple membrane bypass” pathway and the generation of reactive oxygen species. The recent recognition of GPCR transactivation of serine/threonine kinase receptors enormously broadens the GPCR signalling paradigm. It may be predicted that the transactivation of serine/threonine kinase receptors would have mechanistic similarities with transactivation of tyrosine kinase pathways; however, initial studies suggest that these two transactivation pathways are mechanistically distinct. Important questions are the relative importance of tyrosine and serine/threonine transactivation pathways, the contribution of transactivation to overall GPCR signalling, mechanisms of transactivation and the range of cell types in which this phenomenon occurs. The ultimate significance of transactivation-dependent signalling remains to be defined but it appears to be prominent and if so will represent a new cell signalling frontier. 相似文献
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Brian Young 《Studies in history and philosophy of science》2004,35(3):645-663
The career of John Jackson (1686-1763), Arian theologian and controversialist, provides a key to unlocking the early reception and quick collapse of a Newtonian natural apologetic originally developed by Samuel Clarke. The importance of friendship and discipleship in eighteenth-century intellectual enquiry is emphasised, and the links between Newton and his followers are traced alongside those of a group of Cambridge Lockeans, led by Jackson’s direct contemporary Daniel Waterland, who proved instrumental in the initial dismantling of Clarke’s brand of Newtonian apologetic. The controversial context of this engagement is shown to have been largely provided by the religiously compromising rise of freethinking, and Tindal’s Christianity as old as the creation (1731) signalled the dangers to proponents of natural religion as an adjunct of Christian apologetic in such a heated atmosphere. Religious division of the sort that resulted paradoxically played into the hands of the freethinkers in the anticlerical atmosphere of the 1730s, and accusations were exchanged between Newtonians and Lockeans accordingly. The dynamic of England’s Enlightenment experience is, then, a complicated one, and, as the career and writings of Jackson and William Whiston demonstrate, it was one which absorbed as well as repudiated ‘enthusiasm’. 相似文献
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董文伟 《科技情报开发与经济》2004,14(6):296-297
以具体工程为例,介绍了建筑物地基处理的设计、施工中遵循的原则,施工中遇到特殊情况时采取的处理方法和必要的检测方法,对几种桩基的设计要求、施工工艺及过程、质量控制等情况进行了简单阐述。 相似文献
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