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排序方式: 共有580条查询结果,搜索用时 11 毫秒
51.
Armand AS Launay T Pariset C Della Gaspera B Charbonnier F Chanoine C 《Biochimica et biophysica acta》2003,1642(1-2):97-105
FGF6, a member of the fibroblast growth factor (FGF) family, accumulated almost exclusively in the myogenic lineage, supporting the finding that FGF6 could specifically regulate myogenesis. Using FGF6 (-/-) mutant mice, important functions in muscle regeneration have been proposed for FGF6 but remain largely controversial. Here, we examined the effect of a single injection of recombinant FGF6 (rhFGF6) on the regeneration of mouse soleus subjected to cardiotoxin injection, specifically looking for molecular and morphological phenotypes. The injection of rhFGF6 has two effects. First, there is an up-regulation of cyclin D1 mRNA, accounting for the regulating role of a high FGF6 concentration on proliferation, and second, differentiation markers such as CdkIs and MHC I and Tn I increase and cellular differentiation is accelerated. We also show a down-regulation of endogenous FGF6, acceleration of FGFR1 receptor expression and deceleration of the FGFR4 receptor expression, possibly accounting for biphasic effects of exogenous FGF6 on muscle regeneration. 相似文献
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We revisit some aspects of the interpretation of dynamic force spectroscopy experiments. The standard theory predicts that the typical unbinding force f* is linearly proportional to the logarithm of the loading rate r when a single energy barrier controls the unbinding process. For a more complex situation of N barriers, it predicts at most N linear segments for the f* vs. log(r) curve, each segment characterizing a different barrier. Here we extend this existing picture using a refined approximation, provide a more general analytical formula, and show that in principle up to N(N + 1) / 2 segments can show up experimentally. As a consequence, the determination of the positions and even the number of the energy barriers from the experimental data can be ambiguous. A further possible consequence of a multiple-barrier landscape is a bimodal or multimodal distribution of the unbinding force at certain loading rates, a feature recently observed experimentally. 相似文献
55.
Diseases of poplar caused by the native fungal pathogen Sphaerulina musiva and related species are of growing concern, particularly with the increasing interest in intensive poplar plantations to meet growing energy demands. Sphaerulina musiva is able to cause infection on leaves, resulting in defoliation and canker formation on stems. To gain a greater understanding of the different responses of poplar species to infection caused by the naturally co-evolved Sphaerulina species, RNA-seq was conducted on leaves of Populus deltoides, P. balsamifera and P. tremuloides infected with S. musiva, S. populicola and a new undescribed species, Ston1, respectively. The experiment was designed to contain the pathogen in a laboratory environment, while replicating disease development in commercial plantations. Following inoculation, trees were monitored for disease symptoms, pathogen growth and host responses. Genes involved in phenylpropanoid, terpenoid and flavonoid biosynthesis were generally upregulated in P. balsamifera and P. tremuloides, while cell wall modification appears to play an important role in the defense of P. deltoides. Poplar defensive genes were expressed early in P. balsamifera and P. tremuloides, but their expression was delayed in P. deltoides, which correlated with the rate of disease symptoms development. Also, severe infection in P. balsamifera led to leaf abscission. This data gives an insight into the large differences in timing and expression of genes between poplar species being attacked by their associated Sphaerulina pathogen. 相似文献
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Darwin J. Prockop Malcolm Brenner Willem E. Fibbe Edwin Horwitz Katarina Le Blanc Donald G. Phinney Paul J. Simmons Luc Sensebe Armand Keating 《Cytotherapy》2010,12(5):576-578
We address the issue of the potential for malignant transformation of cultured mesenchymal stromal cells (MSC) commonly used in clinical cell-therapy protocols and describe the culture conditions under which tumorigenesis is likely to be an extremely uncommon event. 相似文献
57.
Mixed Phase Solid‐State Plastic Crystal Electrolytes Based on a Phosphonium Cation for Sodium Devices 下载免费PDF全文
Faezeh Makhlooghiazad Daniel Gunzelmann Matthias Hilder Douglas R. MacFarlane Michel Armand Patrick C. Howlett Maria Forsyth 《Liver Transplantation》2017,7(2)
Na batteries are seen as a feasible alternative technology to lithium ion batteries due to the greater abundance of sodium and potentially similar electrochemical behavior. In this work, mixed phase electrolyte materials based on solid‐state compositions of a tri methylisobutylphosphonium (P111i4) bis(tri fluromethanesulphonyl)amide (NTf2) organic ionic plastic crystal (OIPC) and high concentration of NaNTf2 that support safe, sodium metal electrochemistry are demonstrated. A Na symmetric cell can be cycled efficiently, even in the solid state (at 50 °C and 60 °C), for a 25 mol% (P111i4NTf2)–75 mol% NaNTf2 composition at 0.1 mA cm?2 for 100 cycles. Thus, these mixed phase materials can be potentially used in Na‐based devices under moderate temperature conditions. It is also investigated that the phase behavior, conductivity, and electrochemical properties of mixtures of NaNTf2 with this OIPC. It is observed that these mixtures have complex phase behavior. For high compositions of the Na salt, the materials are solid at room temperature and retain a soft solid consistency even at 50 °C with remarkably high conductivity, approaching that of the pure ionic liquid at 50 °C, i.e., 10?3–10?2 S cm?1. 相似文献
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The plant kingdom is constantly challenged by a battery of evolving pathogens. New species or races of pathogens are discovered on crops that were initially bred for disease resistance, and globalization is facilitating the movement of exotic pests. Among these pests, obligate biotrophic parasites make up some of the most damaging groups and have been particularly challenging to study. Here we demonstrate the utility of kinetic PCR (kPCR) (real-time PCR, quantitative PCR) to assess the growth of poplar rust, caused by Melampsora species, by quantification of pathogen DNA. kPCR allowed the construction of reliable growth curves from inoculation through the final stages of uredinial maturation, as well as pathogen monitoring before symptoms become visible. Growth parameters, such as latency period, generation time in logarithmic growth, and the increase in DNA mass at saturation, were compared in compatible, incompatible, and nonhost interactions. Pathogen growth was monitored in different applications dealing with plant pathology, such as host and pathogen diversity and transgenic crop improvement. Finally, the capacity of kPCR to differentiate pathogens in the same sample has broad molecular ecology applications for dynamically monitoring the growth of fungi in their environments or in mixed populations or to measure the efficacy of pest control strategies. 相似文献
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Ingrid Balcells Anna Castelló Anna Mercadé José L Noguera Amanda Fernández-Rodríguez Armand Sànchez Anna Tomàs 《BMC genetics》2011,12(1):1-6