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排序方式: 共有2295条查询结果,搜索用时 31 毫秒
991.
Paula A. Pebsworth Gretchen L. Seim Michael A. Huffman Raymond P. Glahn Elad Tako Sera L. Young 《Journal of chemical ecology》2013,39(3):447-449
Despite widespread consumption of soil among animals, the role of geophagy in health maintenance remains an enigma. It has been hypothesized that animals consume soil for supplementation of minerals and protection against toxins. Most studies determine only the total elemental composition of soil, which may not reflect the amount of minerals available to the consumer. Our aim was to test these hypotheses by evaluating the bioavailability of iron in soil consumed by chacma baboons, using a technique that simulates digestion and adsorption. Our results indicate that, despite variation in absolute iron concentration of soil samples, actual iron bioavailability was low while clay content was quite high. This suggests that iron supplementation is unlikely to be the primary motivation for geophagy in this population, and that detoxification is a plausible explanation. This study demonstrates that more research on bioavailability and clay composition is needed to determine the role geophagy plays in health maintenance. 相似文献
992.
Rejiane da Rosa Schio Bruno Cruz da Rosa Nina Paula Gonalves Salau Evandro Stoffels Mallmann Guilherme Luiz Dotto 《化学工程与技术》2019,42(11):2434-2442
The potential of a chitosan/polyurethane foam (CTS/PU) fixed‐bed column for the removal of Allura Red dye (AR) from aqueous solutions was evaluated. Breakthrough curves were constructed under different conditions and optimized using response surface methodology (RSM). The empirical models Thomas, Yoon‐Nelson, and Bed Depth Service Time (BDST) were fitted to the experimental data. The dynamic models of Yoon‐Nelson and BDST accurately fitted the experimental data. As a result, CTS/PU can be successfully applied in a fixed‐bed adsorption operation to remove AR dye. 相似文献
993.
Pereira Maria Luísa F. da Silva Paula Fernandes Isabel Chastre Carlos 《Bulletin of Engineering Geology and the Environment》2021,80(4):2889-2910
Bulletin of Engineering Geology and the Environment - Basalts are a common lithology found beneath Lisbon and are the predominant rocks of the Volcanic Complex of Lisbon (CVL) (72 Myr). These... 相似文献
994.
Lingonberry Extract Provides Neuroprotection by Regulating the Purinergic System and Reducing Oxidative Stress in Diabetic Rats 下载免费PDF全文
995.
Paula Ofek Keren Miller Anat Eldar-Boock Dina Polyak Ehud Segal Ronit Satchi-Fainaro 《Israel journal of chemistry》2010,50(2):185-203
Although anti-angiogenic agents offer great therapeutic potential, preclinical and clinical studies suggest that these agents, used as monotherapies, have a delayed onset of activity and may have only limited effects on advanced malignancies. Multimodality targeted polymer therapeutics that include anti-angiogenic agents and chemotherapeutics offer the potential for improved efficacy and diminished toxicity in the treatment of cancer and other angiogenesis-dependent diseases. We have recently designed and characterized novel combined anti-angiogenic and antitumor polymer–drug conjugates that target both the tumor and its microenvironment. These conjugates include combined anti-angiogenic and chemotherapeutic drugs, such as TNP-470 and paclitaxel, respectively. Several conjugates also incorporate bisphosphonates as targeting moieties for bone metastases and osteosarcomas or RGD peptidomimetics that target integrins overexpressed on tumor endothelial cells and several tumor cells. Using molecular imaging techniques, we have successfully established dormant and fast-growing tumor mouse models to intravitally non-invasively follow-up tumor progression and response to novel polymer therapeutics. Our results point at our polymer therapeutics as novel bi-specific conjugates targeting both the tumor epithelial and endothelial compartments, warranting their use on a wide spectrum of primary as well as metastatic tumors. The use of these novel architectures will potentially shed light on the molecular mechanisms underlying tumor dormancy and hopefully transform cancer into a chronically-manageable disease. 相似文献
996.
Luísa Gouveia Carla Coutinho Emanuel Mendonça Ana Paula Batista Isabel Sousa Narcisa M Bandarra Anabela Raymundo 《Journal of the science of food and agriculture》2008,88(5):891-896
BACKGROUND: Sweet biscuits, a traditional and nutritious food, can be healthy and very attractive when redesigned to be prepared with the addition of a natural product, the microalgal biomass of Isochrysis galbana. This marine microalga is recognised as a rich source of polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA; 20:5ω3), and is a promising ingredient in the food and feed industries. The importance of PUFA‐ω3 (an alternative to fish oils) in food, and the need to increase the daily intake of these substances to promote a healthier lifestyle is now well known. RESULTS: Traditional butter biscuits were enriched with I. galbana biomass (1% and 3%) and evaluated in terms of colour, texture and fatty acid profile, within 3 months of storage. I. galbana biscuits presented total levels of 100 mg 100 g?1 and 320 mg 100 g?1 of PUFA‐ω3 (EPA + DPA (docosapentaenoic acid; 22:5ω3) + DHA (docosahexaenoic acid; 22:6ω3) for 1% and 3% I. galbana, respectively. CONCLUSION: The enhancement of texture properties, the high stability of colour and texture and the good profile of polyunsaturated fatty acids, with emphasis on EPA and DHA, of the biscuits obtained, reveal a new food market niche opportunity. Copyright © 2008 Society of Chemical Industry 相似文献
997.
Paula A. Conforti Cecilia E. Lupano Diego K. Yamul 《International Journal of Food Science & Technology》2013,48(5):1035-1040
The effect of different amounts of whey protein concentrate (50–150 g kg?1), low and high methoxyl pectin (5–15 g kg?1) on the rheological, thermal, structural properties and sensory quality of mashed potatoes prepared from dried mashed potatoes flakes was investigated. The response surface technique was used to analyse the effects of whey protein concentrate and pectin simultaneously on the consistency index, flow behaviour index, apparent viscosity and Casson plastic viscosity. Both whey protein concentrate and pectin decreased the consistency of the mashed potatoes weakening its structure in all concentrations assayed. Results suggest that whey protein concentrate interacts with high methoxyl pectin through non‐covalent interactions. Based on the sensory evaluation results, up to 100 g kg?1 whey protein concentrate with 15 g kg?1 of low methoxyl pectin and 15 g kg?1 of high methxyl pectin could be incorporated to dried mashed potatoes flakes without losing significantly the sensory quality of the product. 相似文献
998.
Ana Paula Manera Graciele Kuhn André Polloni Marluci Marangoni Giovani Zabot Susana J. Kalil Débora de Oliveira Helen Treichel J. Vladimir Oliveira Marcio A. Mazutti Francisco Maugeri 《Food chemistry》2011
The present work investigates, as a first step, the influences of pressure, exposure time and depressurisation rate on the β-galactosidase activity of permeabilized cells of Kluyveromyces marxianus CCT 7082 submitted to treatment with compressed carbon dioxide, propane and n-butane. In general, results showed that the enzyme activity changes significantly, depending on the experimental conditions investigated, allowing the selection of proper operating conditions for advantageous application of this biocatalyst in hydrolysis reactions. Further, the stability of the enzyme, after high-pressure pre-treatment, was also experimentally monitored, and the results demonstrated that the activities of this biocatalyst were always higher than those of the non-treated one. Finally, evaluation of synthesis of galactooligosaccharides (GOS), using β-galactosidase without treatment and after treatment in compressed fluids, was carried out. Results indicated promising possibilities since the use of n-butane-pre-treated enzyme led to very satisfactory reaction conversions and selectivity. 相似文献
999.
Wann Daniel L.; Waddill Paula J.; Polk Josh; Weaver Stephen 《Canadian Metallurgical Quarterly》2011,15(1):75
Previous work has consistently found positive relationships between levels of sport team identification and social psychological well-being. According to the Team Identification–Social Psychological Health Model, these effects result from the increased social connections fans generate through their interest in the team. The current pair of investigations was designed to test the hypotheses that (1) team identification is positively related to social well-being and (2) team identification is positively related to social connections. In addition, the interrelationships among the variables were investigated (i.e., tests for mediation and moderation). In Study 1, a sample of 161 college students completed a questionnaire assessing demographics, identification with a local team, connections gained by following the team, and social well-being. Results indicated that, as expected, team identification was positively related to both well-being and social connections. Subsequent analyses failed to find evidence that social connections mediated or moderated the relationship between team identification and social psychological health. Study 2 (N = 199 students from the same university as Study 1) replicated the results of the initial study using a more general measure of social connections (i.e., the Campus Connectedness Scale). Discussion includes the implications for the Team Identification–Social Psychological Health Model and the directionality between identification and social connections. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
1000.
Annina Lyly Anu Laulajainen-Hongisto Philippe Gevaert Paula Kauppi Sanna Toppila-Salmi 《International journal of molecular sciences》2020,21(24)
Monoclonal antibodies, biologics, are a relatively new treatment option for severe chronic airway diseases, asthma, allergic rhinitis, and chronic rhinosinusitis (CRS). In this review, we focus on the physiological and pathomechanisms of monoclonal antibodies, and we present recent study results regarding their use as a therapeutic option against severe airway diseases. Airway mucosa acts as a relative barrier, modulating antigenic stimulation and responding to environmental pathogen exposure with a specific, self-limited response. In severe asthma and/or CRS, genome–environmental interactions lead to dysbiosis, aggravated inflammation, and disease. In healthy conditions, single or combined type 1, 2, and 3 immunological response pathways are invoked, generating cytokine, chemokine, innate cellular and T helper (Th) responses to eliminate viruses, helminths, and extracellular bacteria/fungi, correspondingly. Although the pathomechanisms are not fully known, the majority of severe airway diseases are related to type 2 high inflammation. Type 2 cytokines interleukins (IL) 4, 5, and 13, are orchestrated by innate lymphoid cell (ILC) and Th subsets leading to eosinophilia, immunoglobulin E (IgE) responses, and permanently impaired airway damage. Monoclonal antibodies can bind or block key parts of these inflammatory pathways, resulting in less inflammation and improved disease control. 相似文献