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排序方式: 共有1011条查询结果,搜索用时 15 毫秒
1.
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
2.
Chromosomal effects of adeno-associated virus vector integration. 总被引:17,自引:0,他引:17
Adeno-associated virus (AAV) vectors are currently being used in several clinical gene-therapy trials (see the NIH OBA Human Gene Transfer Clinical Trials Database); however, little is known about the chromosomal effects of vector integration. Here we report that integrated vector proviruses are associated with chromosomal deletions and other rearrangements and are frequently located on chromosome 19 (although not at the wildtype AAV integration site). 相似文献
3.
Jacob W. Ulvila 《Journal of forecasting》1985,4(4):377-385
Recent years have seen an increasing cross-fertilization between the fields of decision analysis and forecasting. Decision-analytic models often require forecasts as inputs, and aspects of the Bayesian decision-theoretic framework underlying decision analysis have proved useful to forecasting, particularly in contexts where subjective judgemental inputs are required. This paper describes the use of decision tree analysis for forecasting and illustrates its use for corporate divisional forecasting and planning. A specialized decision-analytic technique, acts as events, is also described and illustrated to forecast a new product's earnings. Conclusions are drawn about the applicability of decision analysis for forecasting. 相似文献
4.
Streaming teaching is adopted gradually for non-English majors in some vocational & technological colleges,and in this thesis the advantages and problems of the method are discussed according to the teaching practice.Furthermore,as a consideration of the streaming teaching,much more progress is expected to be made in the future English teaching with the help of the thesis. 相似文献
5.
设m>1,n,p,q,r,s均为正整数,R是一个具有单位元1的环.证明了:如果R中的任意x,y满足且R具有Q(m)性质,则R是一个交换环.此外,在适当的条件下确立了R的交换性. 相似文献
6.
Rosiane Serrano Luis Henrique Rodrigues Daniel Pacheco Lacerda Priscila Bonalume Paraboni 《Systemic Practice and Action Research》2018,31(5):509-537
Industrial sectors that operate in uncertain environments - with demand variability, product seasonality and different industrialisation structures - need studies that enable identification and forecast trends. Therefore, the development of competitiveness extends beyond a company’s individual performance. Collective action, whether toward consumer markets, supplier markets, competitors and substitutes, can reinforce or help reformulate the current practices of an organisation, besides providing better results in the development of strategies and competitive positioning. Thus, clothing, the sector addressed in this work, is characterised by a long, fragmented, heterogeneous production chain, the competitiveness of which is linked to product differentiation. Therefore, the use of systemic approaches to study this sector is effective. In this sense, this research aims at adapting Systems Thinking and Scenario Planning (STSP) so that it supports the development and planning process in a given sector. Thus, this research applies STSP adapted to an analysis of the clothing sector in the northern region of Rio Grande do Sul State, Brazil. As a result, in academic terms, this research proposed and validated a method for analysing industrial sectors of the clothing industry. In the sectoral context, this research identified elements that leverage the sector’s competitiveness, besides generating knowledge and learning aimed at strengthening the sectoral structure identified, and fostering the formation of a new clothing cluster. 相似文献
7.
Sara B. Seidelmann Janet K. Lighthouse Daniel M. Greif 《Cellular and molecular life sciences : CMLS》2014,71(11):1977-1999
Arteries consist of an inner single layer of endothelial cells surrounded by layers of smooth muscle and an outer adventitia. The majority of vascular developmental studies focus on the construction of endothelial networks through the process of angiogenesis. Although many devastating vascular diseases involve abnormalities in components of the smooth muscle and adventitia (i.e., the vascular wall), the morphogenesis of these layers has received relatively less attention. Here, we briefly review key elements underlying endothelial layer formation and then focus on vascular wall development, specifically on smooth muscle cell origins and differentiation, patterning of the vascular wall, and the role of extracellular matrix and adventitial progenitor cells. Finally, we discuss select human diseases characterized by marked vascular wall abnormalities. We propose that continuing to apply approaches from developmental biology to the study of vascular disease will stimulate important advancements in elucidating disease mechanism and devising novel therapeutic strategies. 相似文献
8.
Mohammad Jaber Miriam Maoz Arun Kancharla Daniel Agranovich Tamar Peretz Sorina Grisaru-Granovsky Beatrice Uziely Rachel Bar-Shavit 《Cellular and molecular life sciences : CMLS》2014,71(13):2517-2533
Mammalian protease-activated-receptor-1 and -2 (PAR1 and PAR2) are activated by proteases found in the flexible microenvironment of a tumor and play a central role in breast cancer. We propose in the present study that PAR1 and PAR2 act together as a functional unit during malignant and physiological invasion processes. This notion is supported by assessing pro-tumor functions in the presence of short hairpin; shRNA knocked-down hPar2 or by the use of a truncated PAR2 devoid of the entire cytoplasmic tail. Silencing of hPar2 by shRNA-attenuated thrombin induced PAR1 signaling as recapitulated by inhibiting the assembly of Etk/Bmx or Akt onto PAR1-C-tail, by thrombin-instigated colony formation and invasion. Strikingly, shRNA-hPar2 also inhibited the TFLLRN selective PAR1 pro-tumor functions. In addition, while evaluating the physiological invasion process of placenta extravillous trophoblast (EVT) organ culture, we observed inhibition of both thrombin or the selective PAR1 ligand; TFLLRNPNDK induced EVT invasion by shRNA-hPar2 but not by scrambled shRNA-hPar2. In parallel, when a truncated PAR2 was utilized in a xenograft mouse model, it inhibited PAR1–PAR2-driven tumor growth in vivo. Similarly, it also attenuated the interaction of Etk/Bmx with the PAR1-C-tail in vitro and decreased markedly selective PAR1-induced Matrigel invasion. Confocal images demonstrated co-localization of PAR1 and PAR2 in HEK293T cells over-expressing YFP-hPar2 and HA-hPar1. Co-immuno-precipitation analyses revealed PAR1-PAR2 complex formation but no PAR1-CXCR4 complex was formed. Taken together, our observations show that PAR1 and PAR2 act as a functional unit in tumor development and placenta-uterus interactions. This conclusion may have significant consequences on future breast cancer therapeutic modalities and improved late pregnancy outcome. 相似文献
9.
Systemic Practice and Action Research - This paper explores the usefulness of rich pictures as a method in Systemic Lean Intervention (SLI) process. It combines Lean and Systems Thinking analytical... 相似文献
10.
In this paper, we present an explanatory objection to Norton's material theory of induction, as applied to predictive inferences. According to the objection we present, there is an explanatory disconnect between our beliefs about the future and the relevant future facts. We argue that if we recognize such a disconnect, we are no longer rationally entitled to our future beliefs. 相似文献