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排序方式: 共有794条查询结果,搜索用时 15 毫秒
91.
Silvia Nappini Danil W. Boukhvalov Gianluca D'Olimpio Libo Zhang Barun Ghosh Chia‐Nung Kuo Haoshan Zhu Jia Cheng Michele Nardone Luca Ottaviano Debashis Mondal Raju Edla Jun Fuji Chin Shan Lue Ivana Vobornik Jory A. Yarmoff Amit Agarwal Lin Wang Lixue Zhang Federica Bondino Antonio Politano 《Advanced functional materials》2020,30(22)
By means of theory and experiments, the application capability of nickel ditelluride (NiTe2) transition‐metal dichalcogenide in catalysis and nanoelectronics is assessed. The Te surface termination forms a TeO2 skin in an oxygen environment. In ambient atmosphere, passivation is achieved in less than 30 min with the TeO2 skin having a thickness of about 7 Å. NiTe2 shows outstanding tolerance to CO exposure and stability in water environment, with subsequent good performance in both hydrogen and oxygen evolution reactions. NiTe2‐based devices consistently demonstrate superb ambient stability over a timescale as long as one month. Specifically, NiTe2 has been implemented in a device that exhibits both superior performance and environmental stability at frequencies above 40 GHz, with possible applications as a receiver beyond the cutoff frequency of a nanotransistor. 相似文献
92.
Anna Maria Piras Ylenia Zambito Susi Burgalassi Daniela Monti Silvia Tampucci Eleonora Terreni Angela Fabiano Federica Balzano Gloria Uccello-Barretta Patrizia Chetoni 《Journal of materials science. Materials in medicine》2018,29(4):42
The ocular bioavailability of lipophilic drugs, such as dexamethasone, depends on both drug water solubility and mucoadhesion/permeation. Cyclodextrins and chitosan are frequently employed to either improve drug solubility or prolong drug contact onto mucosae, respectively. Although the covalent conjugation of cyclodextrin and chitosan brings to mucoadhesive drug complexes, their water solubility is restricted to acidic pHs. This paper describes a straightforward grafting of methyl-β-cyclodextrin (MCD) on quaternary ammonium chitosan (QA-Ch60), mediated by hexamethylene diisocyanate. The resulting product is a water-soluble chitosan derivative, having a 10-atom long spacer between the quaternized chitosan and the cyclodextrin. The derivative is capable of complexing the model drug dexamethasone and stable complexes were also observed for the lyophilized products. Furthermore, the conjugate preserves the mucoadhesive properties typical of quaternized chitosan and its safety as solubilizing excipient for ophthalmic applications was preliminary assessed by in vitro cytotoxicity evaluations. Taken as a whole, the observed features appear promising for future processing of the developed product into 3D solid forms, such as controlled drug delivery systems, films or drug eluting medical devices. 相似文献
93.
94.
Designing Dual Transglutaminase 2/Histone Deacetylase Inhibitors Effective at Halting Neuronal Death 下载免费PDF全文
Dr. Manuela Basso Dr. Huan Huan Chen Dr. Debasmita Tripathy Dr. Mariarosaria Conte Dr. Kim Y. P. Apperley Dr. Angela De Simone Prof. Dr. Jeffrey W. Keillor Prof. Dr. Rajiv Ratan Dr. Angela Nebbioso Dr. Federica Sarno Prof. Dr. Lucia Altucci Dr. Andrea Milelli 《ChemMedChem》2018,13(3):227-230
In recent years there has been a clear consensus that neurodegenerative conditions can be better treated through concurrent modulation of different targets. Herein we report that combined inhibition of transglutaminase 2 (TG2) and histone deacetylases (HDACs) synergistically protects against toxic stimuli mediated by glutamate. Based on these findings, we designed and synthesized a series of novel dual TG2–HDAC binding agents. Compound 3 [(E)‐N‐hydroxy‐5‐(3‐(4‐(3‐oxo‐3‐(pyridin‐3‐yl)prop‐1‐en‐1‐yl)phenyl)thioureido)pentanamide] emerged as the most interesting of the series, being able to inhibit TG2 and HDACs both in vitro (TG2 IC50=13.3±1.5 μm , HDAC1 IC50=3.38±0.14 μm , HDAC6 IC50=4.10±0.13 μm ) and in cell‐based assays. Furthermore, compound 3 does not exert any toxic effects in cortical neurons up to 50 μm and protects neurons against toxic insults induced by glutamate (5 mm ) with an EC50 value of 3.7±0.5 μm . 相似文献
95.
Federica Paganelli Terence Ambra Alessandro Fantechi Dino Giuli 《Telecommunication Systems》2017,64(1):75-85
This paper proposes an instantaneous recovery route design scheme using multiple coding-aware link protection scenarios to achieve higher link cost reduction in the network. In this scheme, two protection scenarios, namely, (i) traffic splitting (TS), and (ii) two sources and a common destination (2SD) are used to integrate multiple sources and a common destination. The proposed scheme consists of two phases. In the first phase, the proposed scheme determines routes for 2SD and TS scenarios of all possible source-destination pairs to minimize the total link cost. In this phase, the network coding is applied to the common path within each scenario, individually. In the second phase, network coding is applied to the common path between two scenarios (or a scenario pair) in order to enhance the resource saving. This phase develops conditions that select the most appropriate combination of scenario pairs, such as TS–TS, 2SD–2SD, and 2SD–TS for network coding, including their proofs. Using these conditions, a heuristic algorithm is introduced in order to select the most appropriate combination of scenario pairs for further enhancing of resource saving. Simulation results show that the proposed scheme outperforms the conventional 1 + 1 protection scheme, the TS scenario, and the 2SD scenario in terms of link cost reduction in the network. 相似文献
96.
A critical analysis of the procedures available in the literature for the serviceability assessment of footbridges in unrestricted pedestrian traffic conditions is presented. Based on a full probabilistic model of the loading, Monte Carlo simulations are carried out and a critical discussion concerning the role of the statistical distribution of the random walking parameters on the footbridge dynamic response is provided. Furthermore, numerical results are compared with the ones obtained by simplified procedures. Finally, a graphical procedure is proposed which permits a simple evaluation of footbridge maximum acceleration as a function of the modal mass, damping ratio and expected average pedestrian flow. 相似文献
97.
Evangelisti C Raffa P Balzano F Barretta GU Vitulli G Salvadori P 《Journal of nanoscience and nanotechnology》2008,8(4):2096-2101
Pt nanoclusters have been generated by reaction of Pt vapour and mesitylene vapour and the role of the mesitylene/platinum ratio and the Pt particle size has been evaluated, quenching the resulting mesitylene solvated Pt atoms with 1,3-divinyltetramethyldisiloxane (DVS) as additional ligand. The Pt particle sizes have been estimated on the basis of DOSY (Diffusion-Ordered SpectroscopY) analysis and information on their structure features have been obtained by combined use of 2D NMR techniques. 相似文献
98.
Modelling urinary excretion of molybdenum after oral and intravenous administration of stable tracers 总被引:1,自引:0,他引:1
Giussani A Cantone MC Höllriegl V Oeh U Tavola F Veronese I 《Radiation protection dosimetry》2007,127(1-4):136-139
An extensive study using stable isotopes of molybdenum as tracers was undertaken to investigate intestinal uptake, systemic kinetics and urinary excretion of molybdenum in healthy human volunteers. In total 63 experiments with 17 volunteers were performed administering the tracers in different chemical forms and measuring their concentrations in blood plasma and urine samples by means of activation analysis and mass spectrometry. Molybdenum was eliminated very rapidly from the circulation. The amount eliminated via the renal pathway was observed to be dependent on several factors, such as form and modality of administration and also the total amount of circulating molybdenum. The fact that the urinary excretion patterns diverged significantly from the current predictions of the International Commission on Radiological Protection model might be relevant when using the model for retrospective intake assessments in case of an accident. On the basis of the experimental data, a more realistic compartmental structure has been presented. 相似文献
99.
A Cuneo R Bigoni GM Rigolin MG Roberti A Bardi N Piva R Milani F Bullrich ML Veronese C Croce F Birg H D?hner A Hagemeijer G Castoldi 《Canadian Metallurgical Quarterly》1999,93(4):1372-1380
Conventional chromosome analysis (CCA) and interphase fluorescence in situ hybridization (FISH) was performed in 42 patients with mantle-cell lymphoma (MCL), with BCL1 rearrangement. The t(11;14)(q13;q32) or 11q abnormalities were detected by CCA in 34 cases, 20 of which had additional aberrations. A normal karyotype was observed in 8 cases. Probes detecting the chromosome aberrations that were observed in at least 3 cases by CCA, ie, +12, 13q14 deletion, and 17p deletion, were used for interphase FISH analysis. FISH detected total or partial +12, 13q14 deletion and 17p- in 28.5%, 52.4%, and 26% of the cases, respectively. The presence of these anomalies was not a function of karyotype complexity. Based on the results of CCA/FISH, three groups of increasing karyotype complexity were recognized: group 1, including 11 patients without detectable aberrations in addition to BCL1 rearrangement; group 2, including 14 patients with 1 to 2 additional anomalies; and group 3, including 17 patients with three or more additional anomalies. Clinical parameters associated with shorter survival were male sex (P =.006) and primary lymph-node involvement compared with primary bone marrow involvement (P =.015). Trisomy 12 was the only single cytogenetic parameter predictive of a poor prognosis (P =.006) and the best prognostic indicator was the derived measure of karyotype complexity (P <.0001), which maintained statistical significance in multivariate analysis (P<.0001). We arrived at the following conclusions: 13q14 deletion occurs at a high incidence in MCL; 17p deletion and total/partial +12 are relatively frequent events in MCL, the latter aberration being associated with a shorter survival; and the degree of karyotype complexity has a strong impact on prognosis in this neoplasia. 相似文献
100.
Francesco Demetrio Lofaro Barbara Cisterna Maria Assunta Lacavalla Federico Boschi Manuela Malatesta Daniela Quaglino Carlo Zancanaro Federica Boraldi 《International journal of molecular sciences》2021,22(19)
Aging is characterized by a progressive decline of skeletal muscle (SM) mass and strength which may lead to sarcopenia in older persons. To date, a limited number of studies have been performed in the old SM looking at the whole, complex network of the extracellular matrix (i.e., matrisome) and its aging-associated changes. In this study, skeletal muscle proteins were isolated from whole gastrocnemius muscles of adult (12 mo.) and old (24 mo.) mice using three sequential extractions, each one analyzed by liquid chromatography with tandem mass spectrometry. Muscle sections were investigated using fluorescence- and transmission electron microscopy. This study provided the first characterization of the matrisome in the old SM demonstrating several statistically significantly increased matrisome proteins in the old vs. adult SM. Several proteomic findings were confirmed and expanded by morphological data. The current findings shed new light on the mutually cooperative interplay between cells and the extracellular environment in the aging SM. These data open the door for a better understanding of the mechanisms modulating myocellular behavior in aging (e.g., by altering mechano-sensing stimuli as well as signaling pathways) and their contribution to age-dependent muscle dysfunction. 相似文献