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21.
G Bianchi D Barone E Lanzarotti R Tettamanti R Porta D Moltrasio A Cedro L Salvetti M Mantovani G Prino 《Canadian Metallurgical Quarterly》1993,238(2-3):327-334
The binding of single-stranded polydeoxyribonucleotides to adenosine A1 and A2 receptors was investigated. Defibrotide, a natural substance with established anti-thrombotic and anti-ischaemic effects, displaced [3H]CHA (N6-cyclohexyl-adenosine) and [3H]NECA (5'-N-ethylcarboxamido-adenosine) concentration dependently, completely and competitively. Ki values of 371 +/- 68 and 688 +/- 115 micrograms/ml (mean +/- S.E.M. of 4-5 replications) were computed for adenosine A1 and A2 sites, respectively. Higher and lower molecular weight polydeoxyribonucleotides displayed comparable affinity, whereas a double-stranded polydeoxyribonucleotide and a polyanion with a negative charge comparable to that of defibrotide were inactive. Defibrotide did not affect the total number of binding sites in radioligand saturation experiments. Defibrotide relaxed the K(+)-contracted guinea-pig trachealis muscle (IC50 = 4001 micrograms/ml) about one-third as potently as the CHA-contracted preparation and as potently as the resting preparation. NECA, a mixed adenosine A1/A2 receptor agonist, behaved similarly. The effects were abolished by the adenosine A1/A2 receptor blocker 8-phenyltheophylline, but not by the selective A1 blocker, 1,3-dipropyl-8-(2-amino-4-chlorophenyl)-xanthine. These results demonstrate that defibrotide binds to adenosine receptors and triggers pharmacological responses comparable to those of a known agonist. 相似文献
22.
Enrique Álvarez‐Casado Bing Zhang Sonia Tello Sandoval Mondelo Pedro 《人机工程学与制造业中的人性因素》2012,22(3):I-I
The following article from Human Factors and Ergonomics in Manufacturing & Service Industries, “Using ergonomic digital human modeling in evaluation of workplace design and prevention of workrelated musculoskeletal disorders onboard small fishing vessel,” by Enrique Álvarez‐Casado, Bing Zhang, Sonia Tello Sandoval and Mondelo Pedro, published online on October 11, 2011 in Wiley Online Library ( www.onlinelibrary.wiley.com ), has been retracted by agreement between the authors, the journal Editors‐in‐Chief, Waldemar Karwowski and Gavriel Salvendy, and Publisher Wiley Periodicals, Inc. The retraction has been agreed as these articles were mistakenly published after being rejected. 相似文献
23.
Laura Prati Alberto Villa Francesca Porta Di Wang Dangsheng Su 《Catalysis Today》2007,122(3-4):386-390
The liquid phase oxidation of glycerol with oxygen has been studied using mono and bimetallic catalysts based on Au and Pd metals supported on activated carbon, in order to study the effect of the metal on the distribution of the products and on activity of catalysts. It was found that by using bimetallic catalysts (Au–Pd) a strong synergistic effect was shown. By using a preformed nucleating centre we were able to obtain a single alloyed phase, which allowed us to address the synergistic effect to the presence of alloyed Au/Pd. The advantage of using this latter catalyst lies not only in the high activity but also in a prolonged catalyst life. Although a partial leaching of palladium and assembling of the particles have been revealed by ICP and HRTEM respectively, activity after 10 re-cycles decreased less than expected (about 10%). 相似文献
24.
Carlos Rivas-Costa Luis Anido-Rifón Miguel A. Gómez-Carballa Sonia Valladares-Rodríguez Roberto Soto-Barreiros 《International journal of human-computer interaction》2014,30(6):480-494
This article discusses a modular, accessible platform that provides a computing environment for people with disabilities accessible through adapted control devices and the television set at users’ homes. Relying on a standard television set as the presentation device allows dependent individuals, especially people with disabilities, to introduce new technological advances in communication and information management in their everyday lives. As a proof-of-concept, the solution presented offers a collection of educational and training services related to teleworking and the search of employment targeted to people with disabilities. A smart job advisor included among these services, which was designed to help our target users to locate job offers that best suit the abilities and disabilities of a particular individual, is also discussed to illustrate how semantic technologies can be applied to increase the perceived accessibility and inclusion by reducing the dependence from other persons. The platform developed, the introduction of semantic technologies, and the way adapted interfacing and presentation devices were integrated may also serve as inspiration to provide services to people with disabilities. 相似文献
25.
Manganese ferrite nanoparticles synthesized through a nanocasting route as a highly active Fenton catalyst 总被引:2,自引:0,他引:2
Teresa Valds-Solís Patricia Valle-Vign Sonia lvarez Gregorio Marbn Antonio B. Fuertes 《Catalysis communications》2007,8(12):2037-2042
Spinel ferrite MnFe2O4 nanoparticles were synthesized by means of a nanocasting technique using a low-cost mesoporous silica gel as a hard template. The magnetic nanoparticles, of <10 nm diameter and with a surface area of around 100 m2/g, were tested as a heterogeneous Fenton catalyst for the decomposition of hydrogen peroxide under neutral and basic conditions. This catalyst shows a much higher activity than previous heterogeneous catalysts reported in the literature, which is mainly ascribed to its small particle size. Furthermore, the magnetic catalyst can be easily separated from the reaction medium by means of an external magnetic field. The effects of residual silica and the purity of the catalyst (hematite formation) on catalytic activity have been studied and correlated. The results obtained show this catalyst to be a suitable candidate for the removal of pollutants in wastewaters by means of the Fenton heterogeneous reaction. 相似文献
26.
Goubault M Cortesero AM Paty C Fourrier J Dourlot S Le Ralec A 《Microscopy research and technique》2011,74(12):1145-1153
Already parasitized hosts are often of poorer quality than healthy hosts. It is therefore usually advantageous for parasitoid females to recognize and reject them. Parasitized hosts can be identified on the basis of various physical or chemical marks present on the surface or inside the hosts or their surroundings in the case of concealed host. Here we studied host discrimination behaviors of females of a certain population of Pachycrepoideus vindemmiae, a solitary ectoparasitoid, which are known to reject large-sized parasitized hosts after an abdominal examination of their surface. We first investigated females' recognition behaviors of host parasitism status when confronted to small-sized hosts (Drosophila melanogaster pupae) as host size may influence the use of different cues for host selection. We showed that, in such a situation, females also discriminate parasitized hosts after an external host exploration with the tip of their ovipositor sheath (third valvulae). We then described the sense organs present on the different parts of the ovipositor by means of scanning and transmission electron microscopy analysis. As the extremity of the third valvulae bears only one type of sensilla that appears to be chemoreceptors, we considered these sensilla as highly likely to be involved in host discrimination in P. vindemmiae. To our knowledge, this is the first time that receptors located on the ovipositor sheath are described as implicated in host discrimination in parasitoid wasps. We discuss potential chemical markers that might be detected by these receptors. 相似文献
27.
Robert P. Kurshan Michael Merritt Ariel Orda Sonia R. Sachs 《Formal Methods in System Design》1994,5(3):227-244
In [11], an induction principle for processes was given which allows one to apply model-checking techniques to parameterized families of processes. A limitation of the induction principle is that it does not apply to the case in which one process depends directly upon a parameterized number of processes, which grows without bound. This would seem to preclude its application to families ofN processes interconnected in a star topology. Nonetheless, we show that if the dependency can be computed incrementally, then the direct dependency upon the parameterized number of processes may be re-expressed recursively in terms of a linear cascade of processes, yielding in effect a linearization of the inter-process dependencies and allowing the induction principle to apply.A previous version of this paper appears in the Proceedings of CAV 1993 (LNCS 697). 相似文献
28.
Sonia M. Rogacheva Margarita J. Kuntcheva Ivan N. Panchev Tzvetan D. Obretenov 《European Food Research and Technology》1995,200(1):52-58
The influence of the water content, molar ratio, time and temperature on the formation of nondialysable melanoidins produced by the interaction ofl-ascorbic acid and glycine has been studied. The isolated polymers have been characterized by spectrum analysis and fractionated using gel chromatography. The rate constants of the reaction for temperatures of 90°C, 100°C and 110°C have been calculated and are (0.84±0.29) x 10?5 x s?1, (1.33±0.14) x 10?5 x s?1 and (5.30±0.37) x 10?5 x s?1 respectively. The activation energy of the reaction has been determined to be 106.07±32.47 kJ/mol. 相似文献
29.
Naderi Sonia Khosroazad Somayeh Abedi Ali 《International Journal of Wireless Information Networks》2022,29(3):240-249
International Journal of Wireless Information Networks - With exponential growth in the number of wireless devices and limited available spectrum, the problem of spectrum sharing remains in... 相似文献
30.