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排序方式: 共有856条查询结果,搜索用时 15 毫秒
101.
Natalie Carrier Denise Ouellet Gale E West 《Revue canadienne de la pratique et de la recherche en diététique》2007,68(1):14-20
PURPOSE: Links between food service characteristics and residents' risk of malnutrition were examined. METHODS: Cognitively intact residents meeting inclusion criteria and living in one of 38 participating nursing homes were randomly sampled. The final sample consisted of 132 residents, who were screened for risk of malnutrition and completed a face-to-face interview questionnaire about dining experiences. Additional data came from participants' medical charts, and each institution's food service manager completed a written questionnaire. Frequencies and logistic regressions were used to describe the sample and to examine relationships between risk of malnutrition and food service characteristics. RESULTS: Overall, 37.4% of participants were at risk of malnutrition. Food service factors, including food packages, lids, and dishes that were difficult to manipulate (b=0.285, p=0.009), bulk food-delivery systems (b=1.329, p=0.036), overall food satisfaction (b=0.253, p=0.044), menu cycle length (b=-2.162, p=0.003), and porcelain dishes (b=-0.345, p=0.052), all were significantly associated with risk of malnutrition. CONCLUSIONS: Our findings clearly show a need for nursing homes to modify certain aspects of food service that may increase the risk of malnutrition among cognitively intact residents. 相似文献
102.
The response of a potential nonpathogenic surrogate organism to a particular treatment should closely mimic the response of the target pathogenic organism. In this study, growth characteristics (generation time, lag phase duration, and maximum population), pH at stationary phase, and survival characteristics (level of attachment and survival on apple surfaces, resistance to hydrogen peroxide decontamination treatments, and thermal resistance at 60 degrees C) of 15 nonpathogenic generic Escherichia coli strains and one nonpathogenic E. coli O157:H43 strain were compared with those of two E. coli O157:H7 strains and two Salmonella strains. Few differences in growth characteristics or pH at stationary phase were evident between nonpathogenic and pathogenic strains tested. However, considerably more separation among strains was seen following investigation of survival characteristics. E. coli ECRC 97.0152, which does not contain genes encoding for known virulence factors associated with E. coli O157:H7, appears to be a good surrogate candidate, with growth and survival characteristics similar to those of E. coli O157:H7 strains. The less heat-resistant surrogate strains E. coli NRRL B-766 and NRRL B-3054 and E. coli ATCC 11775, ATCC 25253, and ATCC 25922 may be used when attempting to model the heat resistance of Salmonella Montevideo G4639 and Salmonella Poona RM 2350, respectively. These surrogate strains may be useful for evaluating the efficacy of intervention steps in reducing populations of selected strains of E. coli O157:H7 and Salmonella in processing environments where these pathogens cannot be introduced. 相似文献
103.
Marina G.B. Aleixo Carla A.B. Sass Rafael M. Leal Tiago M. Dantas Mônica M. Pagani Tatiana C. Pimentel Mônica Q. Freitas Adriano G. Cruz Denise R.P. Azeredo Erick A. Esmerino 《International Journal of Food Science & Technology》2021,56(1):61-68
Social media has experienced rapid growth in recent years and has been subjected of discussions on a wide range of topics including new lifestyles and eating habits, providing a great opportunity to obtain spontaneous consumer information. In this sense, the present work aimed to understand the perception of Twitter® users about themes of veganism and plant-based diets. The social networking data mining methodology was applied to measure the relationship between both terms. The significant differences found were analysed using the global chi-square (χ2) test, and their sources of variation were investigated by the chi-square per cell. The results indicate that the vegan group's posts are more related to the categories of recipes, trends, criticism and negative comments about veganism, being more often citing sources when compared to the other group. The results of the plant-based diet group are more significantly related to the impacts of nutrition, physical activity and consumer health. In conclusion, Twitter® has proved to be an interesting tool for obtaining data on (re) produced food publications on social media and their results can guide the market and the academic environment in creating new products, services and marketing strategies to answer the needs of specific consumers. 相似文献
104.
Tania Aparecida Becker‐Algeri Denise Castagnaro Kennidy de Bortoli Camila de Souza Deisy Alessandra Drunkler Eliana Badiale‐Furlong 《Journal of food science》2016,81(3):R544-R552
This paper presents a literature review of the occurrence of several mycotoxins in bovine milk and dairy products, because it is the main type of milk produced and marketed worldwide. Mycotoxins are produced by different genera of filamentous fungi and present serious health hazards such as carcinogenicity and mutagenicity. Under favorable growth conditions, toxigenic fungi produce mycotoxins which contaminate the lactating cow's feedstuff. During metabolism, these mycotoxins undergo biotransformation and are secreted in milk. Data show that there is a seasonal trend in the levels of mycotoxins in milk, with these being higher in the cold months probably due to the prolonged storage required for the cattle feeds providing favorable conditions for fungal growth. Good agricultural and storage practices are therefore of fundamental importance in the control of toxigenic species and mycotoxins. Although aflatoxins (especially aflatoxin M1) are the mycotoxins of greater incidence in milk and dairy products, this review shows that other mycotoxins, such as fumonisin, ochratoxin A, trichothecenes, zearalenone, T‐2 toxin, and deoxynivalenol, can also be found in these products. Given that milk is widely consumed and is a source of nutrients, especially in childhood, a thorough investigation of the occurrence of mycotoxins as well the adoption of measures to minimize their contamination of milk is essential. 相似文献
105.
Ludmilla Santos Silva de Mesquita Tássio Rômulo Silva Araújo Luz José Wilson Carvalho de Mesquita Denise Fernandes Coutinho Flavia Maria Mendonça do Amaral Maria Nilce de Sousa Ribeiro 《Food Reviews International》2019,35(2):105-131
Lamiaceae is among the largest families of flowering plants with about 250 genera and over 7,000 species distributed around the world. It is considered as the important source of essential oils, for example, menthol, geraniol, eucalyptol, camphor and thymol. Therefore, it is imperative to study these economically important compounds under in vitro conditions for their sustainable and enhanced production. In addition to proven biological activities, essential oils from this family have recently been evaluated for anticancer activities and considered as a source of anticancer drugs. Mechanisms involved in the essential oils-mediated antiproliferative activity include cell cycle arrest, apoptosis and DNA repair mechanisms. Essential oils also act in the reduction of tumors, inhibiting metastasis and as anti-multidrug resistance molecules. The aim of this review is to assess the anticancer properties of essential oils obtained from different members of family Lamiaceae. The available reports on active components of essential oils and their effect on cancer type and cell line have been discussed. Biotechnological studies to improve the production of essential oils have also been highlighted. Various methods have been adopted to obtain essential oils under in vitro conditions from different plant species of family Lamiaceae, and their production is affected by culture conditions, cultivation mode, utilization of nutrient media and plant growth regulators. The literature survey suggests that essential oils obtained from family Lamiaceae have perspective for the development of new alternatives for disease treatment and prevention. 相似文献
106.
Maria Elisa Melo Branco de Araújo Yollanda E. Moreira Franco Thiago Grando Alberto Mariana Alves Sobreiro Marco Aurélio Conrado Denise Gonçalves Priolli Alexandra C.H. Frankland Sawaya Ana Lucia T.G. Ruiz João Ernesto de Carvalho Patrícia de Oliveira Carvalho 《Food chemistry》2013
Bioavailability and biological properties of flavonoid glycosides can be improved after the enzymatic hydrolysis of specific glycosyl groups. In this study, we evaluate the antioxidant and antiproliferative potential of rutin after enzymatic hydrolysis performed by α-l-rhamnosidases (hesperidinase from Penicillium sp. and naringinase from Penicillium decumbens) previously heated at 70 °C for 30 min to inactivate the undesirable β-d-glucosidase activity. The highest in vitro antioxidant activity determined by DPPH radical scavenging was achieved with rutin hydrolyzed by hesperidinase. Rutin was predominantly bioconverted into quercetin-3-glucoside. There was no statistical difference between xanthine oxidase inhibition by rutin before and after hydrolysis. However, in vitro inhibitory activity against ten human tumor cell lines showed that hydrolyzed rutin exerted a more potent antiproliferative effect than quercetin and rutin on various cancer cell lines, specially glioma, and ovarian and breast adenocarcinomas. These results indicate that quercetin-3-glucoside could be a promising functional derivative obtained by rutin hydrolysis. 相似文献
107.
The effectiveness of ozone and acidulant treatments in extending the refrigerated shelf life of fresh-cut potatoes 总被引:1,自引:0,他引:1
Calder BL Skonberg DI Davis-Dentici K Hughes BH Bolton JC 《Journal of food science》2011,76(8):S492-S498
Abstract: The objective of the study was to determine the effectiveness of acidulant dip treatments (with or without aqueous ozone) to reduce enzymatic browning and to extend the shelf life of fresh‐cut potato slices during refrigerated storage (4 °C) for 28 d. Potato slices subjected to aqueous ozone (2 ppm) had significantly (P≤ 0.05) higher L‐values and lower a‐values, but ozone did not appear to have any effect on aerobic plate counts (APCs) or polyphenol oxidase (PPO) activity. NatureSeal (NS) and sodium acid sulfate (SAS) were the most effective acidulant treatments in reducing browning (significantly [P≤ 0.05] higher L‐values, lower a‐values, and browning index values) regardless of ozone treatment. NS and SAS also had lower PPO activity compared to other treatments on days 0 and 28, and significantly (P≤ 0.05) lower APCs (≤2.00 log CFU/g) over refrigerated storage. Therefore, the SAS treatment was comparable to NS, a commercially available product, and showed promise as an effective antibrowning dip to reduce browning and spoilage in fresh‐cut potato products. Practical Application: A 1% SAS dip treatment which included 1% citric and 1% ascorbic acid was found to be an effective antibrowning dip for fresh‐cut potatoes along with NatureSeal®'s PS‐10, compared to other treatments. They were both effective in maintaining low microbial counts over refrigerated storage. Additionally, aqueous ozone washes (2 ppm) showed significant benefits to reduce browning; however, ozone did not affect microbial counts or PPO enzyme activity. Therefore, the SAS treatment could have potential use in the fruit and vegetable industry to reduce browning and spoilage in fresh‐cut potato products. 相似文献
108.
Discusses the articles contained in the present volume addressing the issue of will and the frequent disconnect between what people intend to do and what they actually do. The authors in the series suggest that people perceive themselves to have more control over everyday behavior than they actually do. The authors present a conceptual and empirical framework for understanding the causes of behavior for the times when it is recognized that "will" has broken down and people are unable to act as they desire. According to the authors, the source of behavioral control comes not from active awareness but from subtle cues in the environment and from thought processes and information not readily accessible to consciousness. The theory and data presented in these articles represent recent fundamental breakthroughs in the understanding of motivations, free will and behavioral control. The premise of the 4 articles is this: There are mental activations of which we are unaware and environmental cues to which we are not consciously attending that have a profound effect on our behavior and that help explain the complex puzzle of human motivation and actions that are seemingly inexplicable, even to the individual performing the actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Mary Ann B. Meador Denise Hardy-Green Judith V. Auping James R. Gaier Lesley Ann Ferrara Demetrios S. Papadopoulos James W. Smith Dennis J. Keller 《应用聚合物科学杂志》1997,63(7):821-834
A method to generate conductive films composed of small amounts of conductive polymer absorbed into the surface of polyimide films has been optimized. Both pyrrole (PY) and 3-methylthiophene (3MT) were evaluated as precursors for the conductive phase. Predictive models were empirically derived for each precursor to describe the effects of polymerization variables on the conductivity of the films. The variables studied were found to be highly synergistic. An optimum set of conditions was found for each conductive polymer that produces the highest conductivity. Using p-3MT as the conductive phase, films with conductivity as high as 5.7 Ω−1 cm−1 can be produced, an improvement of four orders of magnitude over previously reported results with Kapton as a base polymer. The highest conductivity achieved using p-PY as the conductive phase was 0.041 Ω−1 cm−1, still a two order of magnitude improvement over previously reported results. Mean mechanical properties of the 3MT-treated films were not significantly lower than that for untreated Kapton. The conductivities of p-3MT/Kapton films tested over time under ambient temperature in air persist fairly well for 300 days. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 821–834, 1997 相似文献
110.