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排序方式: 共有458条查询结果,搜索用时 37 毫秒
81.
Bescós R Rodríguez FA Iglesias X Knechtle B Benítez A Marina M Padullés JM Torrado P Vazquez J Rosemann T 《Journal of the International Society of Sports Nutrition》2012,9(1):3
Background
Information about behavior of energy intake in ultra-endurance cyclists during a 24-hour team relay race is scarce. The nutritional strategy during such an event is an important factor which athletes should plan carefully before the race. The purpose of this study was to examine and compare the nutritional intake of ultra-endurance cyclists during a 24-hour team relay race with the current nutritional guidelines for endurance events. Additionally, we analyzed the relationship among the nutritional and performance variables. 相似文献82.
Fernanda Montenegro Barbosa Camila Valdejane Silva de Souza Ellane Sabryna Ribeiro Paulo Roberto Medeiros de Azevedo Karla Suzanne Florentino da Silva Chaves Damasceno Larissa Mont'Alverne Juc Seabra 《Journal of Food Safety》2021,41(1):e12869
The aim of the study was to evaluate the overall hygienic–sanitary conditions of university hospitals foodservices and assess food safety knowledge and self‐reported practices of food handlers. A self‐administered questionnaire based on sanitary standards for foodservices was given to 123 food handlers from three public hospitals. Microbiological analysis of food handling surfaces and food hygiene inspections were also performed. Food handlers' self‐reported knowledge and practices reached satisfactory levels (77.2% and 78.1%, respectively), and showed a significant positive intercorrelation (p < .05). Food hygiene inspections in the hospitals foodservices presented a 60.9% average of adequacy and microbiological analysis results showed that 66.7% of the evaluated surfaces presented significant contamination by mesophilic bacteria. The presence of coliforms at 45°C above the safety limit was identified in 47.9% of the surfaces. The results showed a need for motivating hospital food handlers to practice the safe handling knowledge that they have demonstrated in theory. 相似文献
83.
International Regulations of Propolis Quality: Required Assays do not Necessarily Reflect their Polyphenolic‐Related In Vitro Activities 下载免费PDF全文
Raquel Bridi Gloria Montenegro Gabriel Nuñez‐Quijada Ady Giordano Maria Fernanda Morán‐Romero Isaac Jara‐Pezoa Hernán Speisky Elias Atala Camilo López‐Alarcón 《Journal of food science》2015,80(6):C1188-C1195
Propolis has been proposed as a polyphenolic‐rich natural product potentially able to be used for human consumption or even for medicinal proposes. To guarantee a minimum phenolic and flavonoid content and as consequence of their related‐biological activities, international requirements of propolis quality are commonly applied. In this work we assessed phenolic and flavonoid contents of propolis; the antioxidant capacity (toward peroxyl radicals and hypochlorous acid); the ability to generate nitric oxide (NO); and, finally the antimicrobial activity of 6 propolis samples from the VI region of Chile. Our results show that the total phenolic and flavonoid content of propolis samples are not always in agreement with their polyphenolic‐associated in vitro activities. For example, P03 and P06 samples showed the lowest (25 ± 4 GAE/g propolis) and the highest (105 ± 3 GAE/g propolis) total phenolic content, respectively. This was in agreement with flavonoid content and their Oxygen Radical Absorbance Capacity (ORAC) activity. However, this dependence was not observed toward HOCl, NO release and antimicrobial activity. Based on our results, we consider that, in order to guarantee the antioxidant or antimicrobial in vitro effects, the international regulations of propolis quality should contemplate the convenience of incorporating other simple analytical test such as ORAC or antimicrobial tests. 相似文献
84.
This article summarizes the background and a few preliminary results concerning project 7 of the NCCR Chemical Biology. The general objective is to explore new concepts for cellular uptake, membrane tunneling, sensing and labeling. Emphasis is on the use of dynamic covalent chemistry for counterion activation, slow release of polyions and fluorescent probes, and the generation of activator libraries and polyions that grow and shrink. 相似文献
85.
Sáez-Ayala M Sánchez-del-Campo L Montenegro MF Chazarra S Tárraga A Cabezas-Herrera J Rodríguez-López JN 《ChemMedChem》2011,6(3):440-449
Despite bioavailability issues, tea catechins have emerged as promising chemopreventive agents because of their efficacy in various animal models. We synthesized two catechin-derived compounds, 3-O-(3,4,5-trimethoxybenzoyl)-(-)-catechin (TMCG) and 3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin (TMECG), in an attempt to improve the stability and cellular absorption of tea polyphenols. The antiproliferative and pro-apoptotic activities of both compounds were analyzed with various cancer cell systems, and TMCG, which was easily synthesized in excellent yield, was more active than TMECG in both melanoma and non-melanoma cell lines. TMCG was also a better inhibitor of dihydrofolate reductase and was more efficiently oxidized by tyrosinase, potentially explaining the difference in activity between these epimers. 相似文献
86.
Julián Jiménez Reinosa David Martín y Marero Adolfo del Campo Miguel Ángel de la Rubia José Francisco Fernández 《Journal of the American Ceramic Society》2013,96(6):1783-1788
Copper and iron in glasses constitute classical aims of study because of the optical effects that they produce. Structured materials are also interesting due to the incorporated functionalities derived from their spatial organization. Here, CuO and Fe2O3 were incorporated into a standard glass, from which glass coatings with different thicknesses were studied. Whereas iron cations dissolved in the glassy matrix, copper cations saturated it and crystallized at the surface, forming a hierarchical microstructure. The surface microstructure consisted of crystallizations of Tenorite (CuO) forming interconnected walls. The walls surrounding areas of glassy matrix gave rise to a cells microstructure. Rutherford Backscattering Spectrometry provided the composition of the samples with high depth resolution, and Raman Confocal Microscopy determined the phases location and their distribution forming the microstructure. The joint information from both techniques allowed high chemical and spatial resolution of the main cations location for the hierarchical surface microstructure. 相似文献
87.
Nanocrystalline particles of La1−xSrxCrO3 (0.000 ≤ x ≤ 0.020) compounds were synthesized in order to investigate the antiferromagnetic (AFM) to paramagnetic (PM) phase transition temperature, g-factor, line width and intensity by electron paramagnetic resonance (EPR). All samples were synthesized by combustion reaction method using strontium nitrate, lanthanum nitrate, chromium nitrate and urea as fuel without subsequent heat treatment. X-ray diffraction patterns of all systems showed broad peaks consistent with orthorhombic structure of LaCrO3. The absence of extra reflections in the diffraction patterns of as-prepared materials ensures the phase purity. The average crystallite sizes determined from the prominent (1 1 2) peak of the diffraction using Scherrer's equation was independent of the addition of Sr2+ ions; being ca. 31–29 nm for x = 0.000 and 0.020, respectively. The EPR line width and intensity were found to be dependent on Sr2+ addition and temperature. However, the AFM–PM transition temperature was found to be independent of strontium concentration, being ca. 296 K. In the PM phase, g-factor was nearly temperature independent with increasing of x. The EPR results indicated that the addition of Sr2+ ions may induce creation of Cr3+–Cr4+ clusters. 相似文献
88.
M. Ángeles Gil M. Teresa López-García M. Asunción Lubiano Manuel Montenegro 《TEST》2001,10(1):183-201
In this paper we develop regression and corrclation analyses of a certain general linear relation between two random elements
whose values are non-empty compact intervals. To this purpose, we firstly extend the least-squares method to deal with the
involved random elements on the basis of a generalized metric defined on the space of the considered intervals. As a complementary
study, a coefficient quantifying the strength of the linear relation between the two random elements is also presented, and
a discussion of the extreme values for this measure is presented. A real-life example illustrates these studies.
Research partially supported by DGESIC/MEC Grants No. DGE-99-PB98-1534 and No. DGE-98-PB97-1282. 相似文献
89.
M. Sánchez Negrette M.A. Montenegro M.S. Catuogno W.J. Lértora M.C. Guanziroli 《Biocell》2007,31(3):391-396
Epidemiological studies in human beings and experimental studies in laboratory animals suggest that milk and dairy products can inhibit effects on the development of some kinds of tumors. Cow milk contains sphingomyelin, butyric acid, conjugated linoleic acid, calcium, vitamin A, carotene and vitamin D. All of these components are known to inhibit the process of carcinogenesis. Our objective was to determine the effect of cow milk and water buffalo milk on the development of colon neoplasias in an experimental model of carcinogenesis in rats induced with 1,2-dimethylhydrazine (DMH). Three-month-old Wistar male rats with an average body weight of 180 g were given a nutritionally adequate diet and drinking water adlivitum, cow milk or water buffalo milk. The milk diets were provided two weeks before the first DMH treatment and their administration was continued during the 10 weeks of DMH treatment. Milk administration finished two weeks after the last DMH doses treatment. Four months after the last carcinogen injection, all surviving animals were sacrificed and examined for intestinal tumors. The number, size, and location of the tumors were recorded and gross pathology was described. Small tumors (< 2.5 mm) were examined by Scanning Electron Microscopy (SEM). Significantly fewer tumors were observed in both groups treated with DMH and supplemented with milk, than in the group treated with DMH without milk administration. 相似文献
90.
Adolfo Hernandez 《软件和集成电路》2022,(6):10-11
<正>和其他运营商相比,电信运营商向5G的过渡要更具挑战性。而通过拥抱云技术,电信运营商能够更好地克服5G技术带来的挑战,包括解决复杂的网络编排,整合新技术、应用和运营模式,开发运行新网络技能组合等。电信运营商正面临着多重挑战:一方面,他们必须开发更多的智能网络(包括边缘计算功能)以应对物联网(IoT)设备数量的快速增长,并研究如何确保5G的投资回报;另一方面,他们还需要应对新冠肺炎疫情造成的财务影响, 相似文献