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排序方式: 共有538条查询结果,搜索用时 15 毫秒
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Miriam Saponaro Isabella Giacomini Giulia Morandin Veronica Cocetta Eugenio Ragazzi Genny Orso Ilaria Carnevali Massimiliano Berretta Mariangela Mancini Francesco Pagano Monica Montopoli 《International journal of molecular sciences》2020,21(23)
Benign prostatic hyperplasia (BPH) is an age-related chronic disorder, characterized by the hyperproliferation of prostatic epithelial and stromal cells, which drives prostate enlargement. Since BPH aetiology and progression have been associated with the persistence of an inflammatory stimulus, induced both by Nuclear Factor-kappa B (NF-κB) activation and reactive oxygen species (ROS) production, the inhibition of these pathways could result in a good tool for its clinical treatment. This study aimed to evaluate the antioxidant and anti-inflammatory activity of a combined formulation of Serenoa repens and Urtica dioica (SR/UD) in an in vitro human model of BPH. The results confirmed both the antioxidant and the anti-inflammatory effects of SR/UD. In fact, SR/UD simultaneously reduced ROS production, NF-κB translocation inside the nucleus, and, consequently, interleukin 6 (IL-6) and interleukin 8 (IL-8) production. Furthermore, the effect of SR/UD was also tested in a human androgen-independent prostate cell model, PC3. SR/UD did not show any significant antioxidant and anti-inflammatory effect, but was able to reduce NF-κB translocation. Taken together, these results suggested a promising role of SR/UD in BPH and BPH-linked disorder prevention. 相似文献
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The Fe/ZrO2 catalyst (1% Fe by weight) shows a strong adsorption capacity toward the nitric oxide (at room temperature the ratio NOFe is ca. 0.5) as a consequence of the formation of a highly dispersed iron phase after reduction at 500–773 K. Nitric oxide is adsorbed mainly as nitrosyl species on the reduced surface where the Fe2+ sites are prevailing, but it is easily oxidised by oxygen forming nitrito and nitrato species adsorbed on the support. However, in the presence of a reducing gas such as hydrogen, carbon monoxide, propane and ammonia at 473–573 K the Fe-nitrosyl species react producing nitrogen, nitrous oxide, carbon dioxide and water, as detected by FTIR and mass spectrometers. The results show that nitric oxide reduction is more facile with hydrogen containing molecules than with CO, probably due the co-operation of spillover effects. Experiments carried out with the same gases in the presence of oxygen show, however, a reduced dissociative activity of the surface iron sites toward the species NOχ formed by NO oxidation and therefore the reactivity is shifted to higher temperatures. 相似文献
25.
Ferran V. García-Ferrer Isabel Pérez-Arjona Germán J. de Valcárcel Eugenio Roldán 《Journal of Modern Optics》2013,60(5):763-773
It is well known that the squeezing spectrum of the field exiting a nonlinear cavity can be directly obtained from the fluctuation spectrum of normally ordered products of creation and annihilation operators of the cavity mode. In this article we show that the output field squeezing spectrum can be derived also by combining the fluctuation spectra of any pair of s -ordered products of creation and annihilation operators. The interesting result is that the spectrum obtained in this way from the linearized Langevin equations is exact, and this occurs in spite of the fact that no s -ordered quasiprobability distribution verifies a true Fokker–Planck equation; that is, the Langevin equations used for deriving the squeezing spectrum are not exact. The (linearized) intracavity squeezing obtained from any s -ordered distribution is also exact. These results are exemplified in the problem of dispersive optical bistability. 相似文献
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Eugenio Roanes-Lozano Luis M. Laita Eugenio Roanes-Macías Michael J. Wester José Luis Ruiz-Lozano Carlos Roncero 《Mathematics and computers in simulation》2009
The length of the Spanish broad gauge network has decreased in the 1956–2006 period. When looking at different railway maps through this period, it seems that the network is offering fewer and fewer alternatives when a line is cut, that is, the network is becoming less and less flexible. The goal of this article is to prove that the flexibility of the Spanish broad gauge network has decreased substantially in the 1956–2006 period. We have considered the network as a graph (ignoring traditional railway quality indicators such as commercial speed, number of tracks, electrifications, signaling, …) and we have chosen two simple indicators as accurate in this sense: the number of cycles (cycles provide an alternative to reach a station if there is a problem in one line) and the number of stations of intermediate degree. To achieve this, we have developed a piece of software that is an ad hoc extension of Maple’s networks package. 相似文献
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Marco Giorgetti Mario Berrettoni Maria Luisa Saladino Eugenio Caponetti 《Journal of Materials Science》2009,44(6):1572-1579
Nanopowders of Yttrium Aluminium Garnet doped with neodymium (Nd:YAG) were investigated by X-Ray Absorption Fine Structure
(XAFS) at the Nd LIII edge in the 1.3–20.8% doping range. XANES spectra appear similar in the full range of the Nd concentration. However, a significant
decrease in the white line intensity of XANES is revealed as the quantity of Nd doping ions increases. Plotting the white
line intensity as a function of Nd doping ions reveals two linear trends with two different slopes, identifying a threshold
value where the neodymium concentration reaches 5 at.% This experimental finding provides support for the existence of a double
doping regime in Nd:YAG nanopowders.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
29.
A Fabry-Perot resonator filled with second-order nonlinear optical material is investigated. Attention is devoted to making the resonator act as a nonlinear mirror for ultralow-intensity light signals that can be switched by a control beam at the second-harmonic frequency. The interaction process is an input-phase-independent parametric downconversion. The theoretical problem is solved through implementation of a dummy variable method optimized for a parametric process. Efficient amplification and bistability of low-intensity signals have been found. 相似文献
30.
Edzer Huitema Gerwin Gelinck Bas van der Putten Eugenio Cantatore Karel Kuijk Kees Hart Dago De Leeuw 《Journal of the Society for Information Display》2002,10(3):195-202
A 2‐in. active‐matrix display was demonstrated, containing 4096 solution‐processed polymer‐based transistors. By using the polymer‐dispersed liquid‐crystal display (LCD) effect, this results in a reflective, low‐power display with paper‐like contrast. The influence of the transistor parameters on the display performance is analyzed by use of a model for charging and discharging of the pixel capacitors. Good agreement was obtained between the model and the experimental data. Scaling behavior allows estimation of the performance required for transistors in a quarter‐VGA display. These requirements are met by solution‐processed pentacene transistors. 相似文献