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排序方式: 共有1671条查询结果,搜索用时 15 毫秒
991.
Daniele Lana Elisa Landucci Costanza Mazzantini Giada Magni Domenico Edoardo Pellegrini-Giampietro Maria Grazia Giovannini 《International journal of molecular sciences》2022,23(20)
Cannabinoids, used for centuries for recreational and medical purposes, have potential therapeutic value in stroke treatment. Cannabidiol (CBD), a non-psychoactive compound and partial agonist of TRPV2 channels, is efficacious in many neurological disorders. We investigated the effects of CBD or Δ9-tetrahydrocannabinol (THC) in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation (OGD), an in vitro model of ischemia. Neuronal TRPV2 expression decreased after OGD, but it increased in activated, phagocytic microglia. CBD increased TRPV2 expression, decreased microglia phagocytosis, and increased rod microglia after OGD. THC had effects contrary to those of CBD. Our results show that cannabinoids have different effects in ischemia. CBD showed neuroprotective effects, mediated, at least in part, by TRPV2 channels, since the TRPV2 antagonist tranilast blocked them, while THC worsened the neurodegeneration caused by ischemia. In conclusion, our results suggest that different cannabinoid molecules play different roles in the mechanisms of post-ischemic neuronal death. These different effects of cannabinoid observed in our experiments caution against the indiscriminate use of cannabis or cannabinoid preparations for recreational or therapeutic use. It was observed that the positive effects of CBD may be counteracted by the negative effects caused by high levels of THC. 相似文献
992.
Jessica Iorio Lorenzo Antonuzzo Emanuela Scarpi Massimo DAmico Claudia Duranti Luca Messerini Clotilde Sparano Damiano Caputo Daniele Lavacchi Domenico Borzomati Alice Antonelli Lorenzo Nibid Giuseppe Perrone Alessandro Coppola Roberto Coppola Francesco di Costanzo Elena Lastraioli Annarosa Arcangeli 《International journal of molecular sciences》2022,23(18)
hERG1 potassium channels are widely expressed in human cancers of different origins, where they affect several key aspects of cellular behaviour. The present study was designed to evaluate the expression and clinical relevance of hERG1 protein in cancer tissues from patients suffering from neuroendocrine tumours (NETs) of ileal (iNETs) and pancreatic (pNETs) origin, with available clinicopathological history and follow-up. The study was carried out by immunohistochemistry with an anti-hERG1 monoclonal antibody. In a subset of samples, a different antibody directed against the hERG1/β1 integrin complex was also used. The analysis showed for the first time that hERG1 is expressed in human NETs originating from either the ileum or the pancreas. hERG1 turned out to have a prognostic value in NETs, showing (i) a statistically significant positive impact on OS of patients affected by ileal NETs, regardless the TNM stage; (ii) a statistically significant positive impact on OS of patients affected by aggressive (TNM stage IV) disease, either ileal or pancreatic; (iii) a trend to a negative impact on OS of patients affected by less aggressive (TNM stage I-III) disease, either ileal or pancreatic. Moreover, in order to evaluate whether ERG1 was functionally expressed in a cellular model of pNET, the INS1E rat insulinoma cell line was used, and it emerged that blocking ERG1 with a specific inhibitor of the channel (E4031) turned out in a significant reduction in cell proliferation. 相似文献
993.
Mariño Julio Alborodo Raúl N. N. Fredlund Lars-Åke Herranz Ángel 《Software and Systems Modeling》2019,18(1):71-105
Software and Systems Modeling - Concurrent systems are hard to program, and ensuring quality by means of traditional testing techniques is often very hard as errors may not show up easily and... 相似文献
994.
Andrea De Silvestri Stefano Stendardo Massimiliano Della Pietra Domenico Borello 《International Journal of Hydrogen Energy》2021,46(28):14988-15007
This study is part of a comprehensive research devoted to the integration of a Calcium Looping (CaL) process with a Molten Carbonate Fuel Cell (MCFC) for the decarbonisation of a full-scale cement plant. In the proposed process, where the energy intensive oxy-combustion occurring in the CaL calciner is replaced with a conventional combustion in air. The CO2-rich gas leaving the calciner is injected into the MCFC cathode while the anode side is fuelled by H2-rich gases produced by a sorption-enhanced reforming (SER) process. The high CO2-concentrated gas leaving the anode will be sent to valorisation processes and/or the CO2 final disposal.Here we focus on modelling, simulation and characterization of the MCFC used as a device for CO2 separation as well as electricity production, here considered as a process by-product. Polarization curves (I–V curves) and Electrochemical Impedance Spectroscopy (EIS) were measured to support the development and the calibration of a semi-empirical model obtained by theoretical consideration.The experimental campaign demonstrated that the fitted model is able to reproduce the real cell performance when varying the temperature, H2 concentration, CO2 concentration at anode and cathode respectively as well as CO2 CaL capture rate.Indeed, the average difference between numerical and experimental results is always below 2%.Results also demonstrated that the MCFC can be usefully considered as an efficient CO2 concentrator, with a CO2 fraction at the anode outlet that is greater than 51% on a dry basis. 相似文献
995.
Andrea Zambotti Mattia Biesuz Renzo Campostrini Sara Maria Carturan Giorgio Speranza Riccardo Ceccato Francesco Parrino Gian Domenico Sorarù 《Ceramics International》2021,47(6):8035-8043
Ceramic aerogels possess intriguing thermophysical properties which make them excellent candidates for high temperature thermal insulators. However, their properties can degrade at high temperature because of crystallization phenomena or because of densification (causing a sensible reduction of their specific surface area and porosity).The polymer derived ceramic (PDC) route is a relatively new way of developing ceramic aerogels. Several aspects influence the properties of the final product when dealing with preceramic polymers, among them their chemical composition and molecular architecture.In this work, we investigated the possibility of producing aerogels belonging to the SiCN system from polysilazanes mixtures, namely perhydropolysilazane (PHPS) and a methyl/vinyl-containing polysilazane, namely Durazane 1800®, thus changing the C/Si ratio of the amorphous pyrolyzed products. It is shown that the chemical composition of the ceramic aerogel affects the main properties of the porous materials, such as thermal stability and specific surface area (SSA). Results show that the presence of carbon in the aerogels inhibits crystallization of Si3N4 up to 1600 °C in N2 and allows to maintain a SSA of ~90 m2/g up to this temperature. 相似文献
996.
Hassan Javed Kai Herbrig Antonio Gianfranco Sabato Domenico Ferrero Massimo Santarelli Christian Walter Federico Smeacetto 《Ceramics International》2021,47(6):8184-8190
In this study, the electrical resistivity of a glass-ceramic sealant is evaluated at 850 °C, for 2800 h under the applied voltage of 1.6 V. The glass-ceramic sealant is sandwiched between two Crofer22APU plates to produce Crofer22APU/Glass-ceramic/Crofer22APU samples. The Crofer22APU/glass-ceramic/Crofer22APU joints show electrical resistivity around 106-107 Ω cm, significantly high to ensure the insulation between two conductive interconnect plates. The detailed SEM-EDS post mortem analysis showed good thermo-mechanical compatibility of the glass-ceramic with the Crofer22APU substrates, thus excluding any detrimental interaction with the metallic interconnect under high applied voltage. XRD analysis of glass-ceramic confirmed the presence of crystalline phases with suitable CTEs, after electrical resistivity under harsh conditions. 相似文献
997.
Juan J. Rivera Antonio Martellucci Philippe Sivac Edoardo Benzi Alberto Pandolfi Domenico de Bernardo Stefano Falzini Giuseppe Codispoti 《International Journal of Satellite Communications and Networking》2019,37(5):397-409
This paper provides an overview of the space segment of the Aldo Paraboni mission on the Alphasat satellite and the technology programme that has developed one of the most powerful geostationary satellites in Europe. The Aldo Paraboni technology demonstration payload, funded by ASI under European Space Agency's Advanced Research in Telecommunications System Programme, was embarked as a hosted payload on the Alphasat satellite, launched on 25 July 2013. The Aldo Paraboni payload is composed of two main elements, an experimental communication payload operating at Q/V bands (COMEX) and a scientific payload formed by 2 beacons at Ka and Q bands (SCIEX). The Aldo Paraboni payload is a key technology element of the Aldo Paraboni Mission, which covers two main objectives: the communication segment of the mission aims at assessing the performance of satellite communication links at Q/V bands and investigating use Fade Mitigation Techniques (FMT, eg, Adaptive Coding and Modulation defined in DVB‐S2 standard), while the scientific segment aims at characterizing in time, space, and frequency the K and Q band radio channel over Europe to permit development and improvement of propagation channels for slant paths. 相似文献
998.
Michele D. Domenico Gabriela C. Collazzo Tatiana R. Pacioni Humberto J. José Regina F. P. M. Moreira 《Chemical Engineering Communications》2019,206(2):158-168
The gasification of coals obtained from important coalfields in Brazil was investigated in 1.0?bar of CO2 using a thermogravimetric analyzer. Tests were carried out in two sequential steps: pyrolysis under N2 at 1213 K and isothermal gasification under CO2 in the temperature range of 1113–1213 K. The kinetic study was performed in the kinetically controlled regime and three gas-solid models were fitted to the experimental data. According to the results, subbituminous coal-chars presented higher reactivities than bituminous types, with maceral and ash compositions playing a key role in the overall process. The reaction rates increased with increasing temperature, with maximum values found in the conversion range of 10–60%. The random pore model that predicts a maximum point of reactivity over the reaction course suitably described the gasification kinetics. Values of activation energy between 146.63(±0.03) kJ/mol and 215.09(±0.05) kJ/mol were found, which are consistent to literature data of coals gasified worldwide. Despite the relatively high ash content (32–45%), the Brazilian coals appeared to be sufficiently reactive to be gasified, thus indicating the significance of this study to the development of gasification process in Brazil. 相似文献
999.
Cortés José A. Aguayo-Torres Mari Carmen Cañete Francisco J. Gómez Gerardo Martos-Naya Eduardo Entrambasaguas J. Tomás 《Wireless Personal Communications》2019,106(1):237-260
Wireless Personal Communications - The application of information and communication technologies to road transportation systems can significantly improve safety and traffic flow. This requires... 相似文献
1000.
Mari C. W. Myhrstad Vanessa D. de Mello Ingrid Dahlman Marjukka Kolehmainen Jussi Paananen Amanda Rundblad Carsten Carlberg Ole Kristoffer Olstad Jussi Pihlajamki Kirsten B. Holven Kjeld Hermansen Lars O. Dragsted Ingibjrg Gunnarsdottir Lieselotte Cloetens Matilda Ulmius Storm Bjrn kesson Fredrik Rosqvist Janne Hukkanen Karl‐Heinz Herzig Ulf Risrus Inga Thorsdottir Kaisa S. Poutanen Markku J Savolainen Ursula Schwab Peter Arner Matti Uusitupa Stine M. Ulven 《Molecular nutrition & food research》2019,63(13)