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排序方式： 共有1158条查询结果，搜索用时 15 毫秒
991.
Deepak Kumar Sinha Dr. Pierre Neveu Dr. Nathalie Gagey Dr. Isabelle Aujard Dr. Chouaha Benbrahim‐Bouzidi Thomas Le Saux Dr. Christine Rampon Dr. Carole Gauron Bernard Goetz Sylvie Dubruille Marc Baaden Dr. Michel Volovitch Prof. Dr. David Bensimon Dr. Sophie Vriz Prof. Dr. Ludovic Jullien Prof. Dr. 《Chembiochem : a European journal of chemical biology》2010,11(5):653-663
We have implemented a noninvasive optical method for the fast control of protein activity in a live zebrafish embryo. It relies on releasing a protein fused to a modified estrogen receptor ligand binding domain from its complex with cytoplasmic chaperones, upon the local photoactivation of a nonendogenous caged inducer. Molecular dynamics simulations were used to design cyclofen‐OH, a photochemically stable inducer of the receptor specific for 4‐hydroxy‐tamoxifen (ERT2). Cyclofen‐OH was easily synthesized in two steps with good yields. At submicromolar concentrations, it activates proteins fused to the ERT2 receptor. This was shown in cultured cells and in zebrafish embryos through emission properties and subcellular localization of properly engineered fluorescent proteins. Cyclofen‐OH was successfully caged with various photolabile protecting groups. One particular caged compound was efficient in photoinducing the nuclear translocation of fluorescent proteins either globally (with 365 nm UV illumination) or locally (with a focused UV laser or with two‐photon illumination at 750 nm). The present method for photocontrol of protein activity could be used more generally to investigate important physiological processes (e.g., in embryogenesis, organ regeneration and carcinogenesis) with high spatiotemporal resolution. 相似文献
992.
993.
Sophie Achard;Irène Gannaz; 《时间序列分析杂志》2024,45(3):421-443
In the general setting of long-memory multivariate time series, the long-memory characteristics are defined by two components. The long-memory parameters describe the autocorrelation of each time series. And the long-run covariance measures the coupling between time series, with general phase parameters. It is of interest to estimate the long-memory, long-run covariance and general phase parameters of time series generated by this wide class of models although they are not necessarily Gaussian nor stationary. This estimation is thus not directly possible using real wavelets decomposition or Fourier analysis. Our purpose is to define an inference approach based on a representation using quasi-analytic wavelets. We first show that the covariance of the wavelet coefficients provides an adequate estimator of the covariance structure including the phase term. Consistent estimators based on a local Whittle approximation are then proposed. Simulations highlight a satisfactory behavior of the estimation on finite samples on multivariate fractional Brownian motions. An application on a real neuroscience dataset is presented, where long-memory and brain connectivity are inferred. 相似文献
994.
995.
Political knowledge and political interest are generally positively influenced by news media exposure. Yet, at the same time, knowledge and interest are among the most important predictors of news media exposure in the first place. We conduct a field experiment (N = 393) as a test of this dual function of knowledge and interest in a realistic news media choice setting. We examine whether preexisting interest and knowledge predict which individuals can be encouraged to read an unfamiliar information-rich newspaper, and if using this newspaper, in turn, has effects on interest and knowledge. Results show that interest and knowledge are predictors of compliance in the experiment. While political knowledge shows some response to the additional news exposure, interest remains stable. 相似文献
996.
Katherine R. Dale Arthur A. Raney Sophie H. Janicke Meghan S. Sanders Mary Beth Oliver 《The Journal of communication》2017,67(6):897-919
Despite the increased attention to eudaimonic media experiences, to date scholars have paid little attention to the specific portrayals responsible for those experiences. Study 1 of this project reports the first systematic content analysis of self-transcendent media—a particular type of eudaimonic media—using a sample of 100 “inspirational” YouTube videos. The presence of 20 specific elicitors associated with self-transcendent emotions was examined and reported. In Study 2, respondents provided real-time self-transcendent emotional reactions while viewing 3 “inspirational” videos. As expected, ratings significantly increased immediately following exposure to each specific elicitor. Thus, this project reports the first empirical evidence directly linking specific representations to content identified as “inspirational” and directly linking those representations to self-transcendent emotional reactions. 相似文献
997.
998.
Karishma B. Patel Sophie Schuller Sébastien P. Facq Ian Farnan 《Journal of the American Ceramic Society》2021,104(7):3632-3651
The aim of this paper was to assess factors affecting primary and secondary phase separation in simplified calcium borosilicate glasses studied for nuclear waste applications. Several glasses with varying [MoO3] and [B2O3] were synthesized and exposed to Au-irradiation to examine compositional effects on glass structure and domain size of separated phases induced by accumulated radiation damage resulting from α-decay over a ~1000 year timeframe. The produced glasses fell within the immiscibility dome of CaO−SiO2−B2O3 and showed a unique microstructure of embedded immiscibility with three identifiable amorphous phases according to electron microscopy, Raman spectroscopy, and diffraction. These glasses were then bombarded with 7 MeV Au3+ ions to a dose of 3 × 1014 ions/cm2 creating an estimated ~1 dpa of damage. Several changes to the morphology, spatial distribution, and size of secondary phases were observed, indicative of significant structural reorganization and changes to the chemical composition of each phase. A general mechanism of coalescence to form larger particles was observed for [MoO3] < 2.5 mol%, whereas segregation to form smaller more evenly distributed particles was seen for [B2O3] ≤ 15 mol% and [MoO3] ≥ 2.5 mol%. These microscopic changes were concurrent to surface-bulk diffusion of Ca and/or Mo ions, where the direction of diffusion was dependent on [B2O3] with a barrier identified at ~20 mol%, as well as cross-phase diffusion of said ions. These modifications occurred in part through the formation of distorted ring structures within the borosilicate network, which enabled the increased dissolution of isolated (MoO4)2− units. Au-irradiation was therefore able to increase the solubility of molybdenum and alter the structure and composition of secondary phases with the extent of modification varying with [MoO3] and [B2O3]/[SiO2], though glasses notably remained heterogeneous. The collective results suggest that radiation and composition can both be used as design tools to modulate the domain size and distribution of separated phases in heterogeneous glasses. 相似文献
999.
Maxime Fieux Sandra Le Quellec Sophie Bartier Andr Coste Bruno Louis Caroline Giroudon Mikail Nourredine Emilie Bequignon 《International journal of molecular sciences》2021,22(12)
FcRn plays a major role in regulating immune homeostasis, but it is also able to transport biologics across cellular barriers. The question of whether FcRn could be an efficient transporter of biologics across the nasal epithelial barrier is of particular interest, as it would allow a less invasive strategy for the administration of biologics in comparison to subcutaneous, intramuscular or intravenous administrations, which are often used in clinical practice. A focused systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. It was registered on the international prospective register of systematic reviews PROSPERO, which helped in identifying articles that met the inclusion criteria. Clinical and preclinical studies involving FcRn and the nasal delivery of biologics were screened, and the risk of bias was assessed across studies using the Oral Health Assessment Tool (OHAT). Among the 12 studies finally included in this systematic review (out of the 758 studies screened), 11 demonstrated efficient transcytosis of biologics through the nasal epithelium. Only three studies evaluated the potential toxicity of biologics’ intranasal delivery, and they all showed that it was safe. This systematic review confirmed that FcRn is expressed in the nasal airway and the olfactory epithelium, and that FcRn may play a role in IgG and/or IgG-derived molecule-transcytosis across the airway epithelium. However, additional research is needed to better characterize the pharmacokinetic and pharmacodynamic properties of biologics after their intranasal delivery. 相似文献
1000.
Samantha L. Cooper Eleanor Boyle Sophie R. Jefferson Calum R. A. Heslop Pirathini Mohan Gearry G. J. Mohanraj Hamza A. Sidow Rory C. P. Tan Stephen J. Hill Jeanette Woolard 《International journal of molecular sciences》2021,22(15)
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the virus responsible for the COVID-19 pandemic. Patients may present as asymptomatic or demonstrate mild to severe and life-threatening symptoms. Although COVID-19 has a respiratory focus, there are major cardiovascular complications (CVCs) associated with infection. The reported CVCs include myocarditis, heart failure, arrhythmias, thromboembolism and blood pressure abnormalities. These occur, in part, because of dysregulation of the Renin–Angiotensin–Aldosterone System (RAAS) and Kinin–Kallikrein System (KKS). A major route by which SARS-CoV-2 gains cellular entry is via the docking of the viral spike (S) protein to the membrane-bound angiotensin converting enzyme 2 (ACE2). The roles of ACE2 within the cardiovascular and immune systems are vital to ensure homeostasis. The key routes for the development of CVCs and the recently described long COVID have been hypothesised as the direct consequences of the viral S protein/ACE2 axis, downregulation of ACE2 and the resulting damage inflicted by the immune response. Here, we review the impact of COVID-19 on the cardiovascular system, the mechanisms by which dysregulation of the RAAS and KKS can occur following virus infection and the future implications for pharmacological therapies. 相似文献