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排序方式: 共有1141条查询结果,搜索用时 15 毫秒
91.
Carole Guillaume Jeremy Pinte Nathalie Gontard Emmanuelle Gastaldi 《Food research international (Ottawa, Ont.)》2010,43(5):1395-1401
The objective of the present work was to understand how the structural, surface, water vapour and gas barrier properties of wheat gluten (WG) coated paper could be influenced by the features of paper. For this purpose, a surface treated paper (TP) and an untreated paper (UTP) were compared. Penetration of WG-coating into the bulk of paper was more pronounced in UTP than TP. This led to the formation of a significant junction zone resulting in an interpenetrated structure for WG–UTP, suggesting a composite-like structure, while a bi-layer one was obtained for WG–TP. Differences in WG penetration were related to the hydrophilicity, roughness and porosity of the paper used. Even though the extent of penetration did not greatly affect the surface properties (water and oil resistance), the transfer properties (water vapour, O2 and CO2) of WG-coated papers were significantly improved when WG-coating highly penetrated: while the WG–TP behaved as a micro-perforated material, the WG–UTP behaved as WG-film. 相似文献
92.
Rachid Boumaza Lydie Huché-Thélier Sabine Demotes-Mainard Eric Le Coz Nathalie Leduc Sandrine Pelleschi-Travier El Mostafa Qannari Soulaiman Sakr Pierre Santagostini Ronan Symoneaux Vincent Guérin 《Food quality and preference》2010,21(8):987-997
The context of ornamental horticulture is considered in order to extend the techniques of sensory and preference evaluation by taking the rosebush as a plant model. In a preliminary study (Boumaza, Demotes-Mainard, Huché-Thélier, & Guérin, 2009), a sensory evaluation was conducted in order to set up a list of attributes. Subsequently, this list was adapted to assess 10 rosebushes. After the control of the panel performance using a multivariate strategy of analysis, the average scores were used in product mapping. The evaluation of the preferences with regard to these rosebushes was undertaken: 253 subjects were asked to rank the products by decreasing order of liking. Thereafter, the preference data were subjected to an internal preference mapping and a cluster analysis. Six homogeneous segments of consumers were eventually retained. By way of performing an external preference mapping, the average ranks were regressed upon the sensory attributes using principal component regression: the preferences of 67% of the consumers were satisfactorily explained by the attributes. 相似文献
93.
Piotr Wacinski Mariusz Gadzinowski Wojciech Dabrowski Justyna Szumilo Jakub Wacinski Nathalie Oru Eric Vicaut Stanislaw Czuczwar Janusz Kocki Teresa Basinska Stanislaw Slomkowski 《International journal of molecular sciences》2021,22(14)
Atherosclerosis involves an ongoing inflammatory response of the vascular endothelium and vessel wall of the aorta and vein. The pleiotropic effects of statins have been well described in many in vitro and in vivo studies, but these effects are difficult to achieve in clinical practice due to the low bioavailability of statins and their first-pass metabolism in the liver. The aim of this study was to test a vessel wall local drug delivery system (DDS) using PLA microstructures loaded with simvastatin. Wistar rats were fed high cholesterol chow as a model. The rat vessels were chemically injured by repeated injections of perivascular paclitaxel and 5-fluorouracil. The vessels were then cultured and treated by the injection of several concentrations of poly(L,L-lactide) microparticles loaded with the high local HMG-CoA inhibitor simvastatin (0.58 mg/kg) concentration (SVPLA). Histopathological examinations of the harvested vessels and vital organs after 24 h, 7 days and 4 weeks were performed. Microcirculation in mice as an additional test was performed to demonstrate the safety of this approach. A single dose of SVPLA microspheres with an average diameter of 6.4 μm and a drug concentration equal to 8.1% of particles limited the inflammatory reaction of the endothelium and vessel wall and had no influence on microcirculation in vivo or in vitro. A potent pleiotropic (anti-inflammatory) effect of simvastatin after local SVPLA administration was observed. Moreover, significant concentrations of free simvastatin were observed in the vessel wall (compared to the maximum serum level). In addition, it appeared that simvastatin, once locally administered as SVPLA particles, exerted potent pleiotropic effects on chemically injured vessels and presented anti-inflammatory action. Presumably, this effect was due to the high local concentrations of simvastatin. No local or systemic side effects were observed. This approach could be useful for local simvastatin DDSs when high, local drug concentrations are difficult to obtain, or systemic side effects are present. 相似文献
94.
Igor V. Levkov Stephanie Cassel Zoia V. Voitenko Nathalie Saffon Armand Lattes Isabelle Rico-Lattes 《Journal of surfactants and detergents》2014,17(1):101-109
In this work, we present the synthesis of cationic surfactants based on 1-aminoisoindole. The physico-chemical properties were studied by conductometry, tensiometry, dynamic light scattering and transmission electron microscopy in water and in formamide. The reactivity of these novel surfactants has been studied at concentrations below and above critical aggregation concentrations (CAC) and it was found that reactions can proceed in structured media without the addition of other catalysts. 相似文献
95.
Steffen Vojacek Lukas Schulig Nathalie Wössner Norman Geist Prof. Dr. Walter Langel Prof. Dr. Manfred Jung Prof. Dr. Dennis Schade Prof. Dr. Andreas Link 《ChemMedChem》2019,14(8):853-864
Indoles are privileged structures in medicinal and bioorganic chemistry that are particularly well suited to serve as platforms for diversity. Among many other therapeutic areas, the indole scaffold has been used to design aromatic compounds useful to interfere with enzymes engaged in the regulation of substrate acylation status, such as sirtuins. However, the planarity of the indole ring is not necessarily optimal for all target enzymes, especially when functionalization with aromatic side chains is required. Replacement of flat scaffolds by nonplanar molecular cores dominated by sp3 hybridization is a common strategy to avoid the disadvantages associated with poor solubility and high promiscuity, while covering less-well-explored areas of chemical space. Thus, we synthesized fragment-like tetrahydroindoles suitable for fragment-based drug discovery as well as a well-characterized small library intended as multipurpose screening compounds. For proof of principle, these compounds were screened against sirtuins 1–3, enzymes known to be addressable by indoles. We found that 2,6,6-trimethyl-4-oxo-4,5,6,7-tetrahydro-1H-indole-3-carboxamides are potent and selective SIRT2 inhibitors. Compound 16 t displayed an IC50 value of 0.98 μm and could serve as exquisite starting point for hit-to-lead profiling. 相似文献
96.
A three-dimensional method for obtaining the bending losses and field distributions of curved integrated optic rib-waveguides is presented. The method is based on a so called 'line method' and relies on a discretisation of the potential in the direction of the rib-heights and leads to Bessel-equations in the radial direction. Good agreement with experimental results is obtained.<> 相似文献
97.
We discuss the introduction of an information system where the dominant coalition claimed project success. While the key users did not use the system as intended and the project goals were not achieved, the project committee reported success to the top management board. Using a multi-methodological approach, we can follow how different stakeholders attributed different meanings to the system introduced over time. The rhetorical tools used are analysed using a narrative methodology. We draw on the social construction of technology and use the concept of relevant social groups to understand the different interests influencing the organisational dynamics. We complement this approach by employing the concepts of organisational power and cultural fit between the new system and the different subcultures. We found that this multiple approach explains well how the acceptance of the new software processes was interpreted differently within the organisation, and also by the software supplier. Although limited, our case study reveals the process of socially constructing the success or failure of an information system using this multiple research approach. We compare our results with the literature on IS failures and we consider the value of combining constructionist and critical approaches through a narrative methodology. 相似文献
98.
Summary The 2,2 bis(4-ethynylphenyl)hexafluoropropane is prepared via an original synthesis's process using a substitution of 2,2 bis(4-triflatephenyl) hexafluoropropane by trimethylsilyl acetylene. In this process ZnO is used to remove the triflate anion formed during the reaction.This diacetylenic compound melts at 37–38°C, exhibits an onset of polymerization at 120°C. After thermal treatment at 250°C, the obtained network shows a softening point at 300°C. This network remains stable in air up to 435°C. 相似文献
99.
Carole Marques Ludovic D’auria Patrice D. Cani Chiara Baccelli Raoul Rozenberg Nike L. Ruibal-Mendieta Géraldine Petitjean Dominique L. Delacroix Joëlle Quetin-Leclercq Jean-Louis Habib-Jiwan Marc Meurens Nathalie M. Delzenne 《Food chemistry》2007,100(3):1265-1271
The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt (Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat (Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food. 相似文献
100.
Psychophysiological reactivity to nonaversive (1-KHz, 70-db tones) and aversive stimuli (shock) was examined in nonalcoholic men with multigenerational family histories (MFH) of alcoholism and family history negative (FH–) men, while sober and after consuming alcohol. In comparison with FH– Ss, sober MFH Ss had significantly larger skin conductance (SC) orienting responses (ORs), shorter OR latencies, slower habituation rates to the tones, and larger increases in heart rate and vasoconstriction to the shock. Alcohol dampened the magnitude of the SC-OR to the tones and the degree of cardiovascular reactivity to the shocks and increased the habituation rate to the tones in MFH Ss only. Alcohol consumption also increased the SC-OR recovery time in FH– Ss only. The MFH Ss' pattern of psychophysiological hyperreactivity is discussed in terms of a potential dysfunction in stimulus–response regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献