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81.
Moderate red wine consumption is associated with decreased risk for cardiovascular disease; however, the underlying mechanisms are not completely understood. The main aim of this study was to investigate the effects of red wine polyphenols (WP) on the oxidizability of human plasma fatty acids, in particular those most involved in the inflammatory response — archidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The oxidizability of the major fatty acids of plasma was determined by measuring their loss gaschromatographycally during peroxidation kinetics induced by 2′-azobis(2-methylpropionamidine)-dihydrochloride. The capacity of WP to scavenge 1,1,diphenyl-2-picryl-hydrazyl (DPPH), superoxide anion and hydroxyl radicals, and trap total peroxyl radicals in plasma (TRAP) was also measured. WP (1.75–5 μg/mL) inhibited DPPH, superoxide anion and hydroxyl radicals and increased TRAP in a dose-dependent manner. WP (1.75 μg/mL) significantly protected all plasma PUFA from peroxidation but the protection of EPA and DHA was higher than that of AA. These results suggest that the association of WP to apolipoproteins makes EPA and DHA less accessible to hydro-soluble radicals than AA, thus providing a biochemical rationale for future ‘in vivo’ studies on the benefits to health of moderate red wine consumption.  相似文献   
82.
The twenty‐first century challenges engineering educators to design learning experiences to strategically and holistically target students' development, including cognitive, psychomotor, social and affective domains. We propose a guide for the design process. The Four‐Domain Development Diagram (4DDD) is a synthesis of learning theory and empirical data. This guide maps the relationships among the major factors that influence learning and presents them in the form of a causal loop diagram, a tool used by systems dynamicists to show how changes in important factors affect other factors within the system. In this paper, we present the theoretical and empirical basis of the 4DDD. We also describe how the 4DDD can be used as a design guide for instructional changes that promote more effective learning experiences for the broader cognitive, social, affective, and psychomotor development required of today's engineering graduate.  相似文献   
83.
Hybrid materials obtained through a Microwave-assisted grafting of organic functional groups on mesoporous silica (MCM-41 type) have been characterized by X-ray powder diffraction, TG-DSC, N2 adsorption, solid state 13C- and 29Si-NMR, TEM and SEM. The studied grafting procedure is effective in the preparation of hybrid organosilicas under solvent-free conditions. Microwaves allows an ultra-fast and clean functionalization of the mesoporous materials and the method has been applied to produce a wide series of functional materials. The hybrid materials maintain the original mesoporous structure when the loading of linked organic groups does not exceed 10 %. In this cases, the slight pore volume reduction is linearly correlated to the organic amount in the product. If functional groups able to interact among them through hydrogen bond are used, hybrid materials exhibit high Organic/SiO2 ratios and low pore volumes due to the formation of a network occluding the pores, where functional groups of free organosilane molecules interacts with the functional groups of molecules linked to the matrix. NMR data confirm that the network is composed by organosilane molecules linked or not to the framework. Acid washing is able to labilize hydrogen bond and open the network. In the case of bulky but chemically inert functionalising agents the network is not produced.  相似文献   
84.
In today’s competitive business environment, Intellectual Capital (IC) management is ever more recognized as a fundamental factor in gaining competitive advantage. Actually, most firms have only a vague idea of how to manage investments in IC and what they should obtain from these investments. As a result, many companies overlook to balance IC investments, overinvesting in some IC components and neglecting other ones. Following this lead, the aim of the paper is to assess the relative importance of IC components, with respect to their contribution to the company value creation, in order to obtain guidelines for IC management and investments.We propose a model for IC evaluation by integrating Fuzzy Logic and Analytic Hierarchy Process (AHP). This Fuzzy AHP approach allows to capture and foster IC dynamics: experts and managers are greatly supported by the use of linguistic variables in the evaluation process of the company intangible assets. Finally, the application of the Fuzzy AHP methodology to a group of ICT service companies is presented.  相似文献   
85.
Surveys the literature on social support and cancer and reports results from an empirical investigation of the factors that led cancer patients to join social support groups. Questionnaire data from 666 21–89 yr old cancer patients show that although most Ss received high levels of social support following cancer, some experienced isolated instances of rejection or did not receive the type of support they wanted from family, friends, and medical caregivers. This appeared to be 1 impetus for joining cancer support groups, although Ss reporting a lack of social support were not generally more likely to join support groups than were other Ss. The Profile of Mood States suggested that attenders were somewhat less likely to be depressed than were nonattenders. In addition, cancer support group attenders were more likely to be White middle-class females, to report having more problems, and to use social support resources of all kinds than were nonattenders. Implications for outreach to cancer patients are discussed, and it is concluded that while support groups may be beneficial for many cancer patients, current programs tend to be used largely by the same segment of the population that uses traditional mental health services. (81 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
生物技术与术材化学、真菌学、生物化学和遗传学结合为制浆造纸工业开发出一种白化真菌产品.在制浆前用其预处理木片,能够降低水材中的树脂含量并提高术片的整体白度,减轻树脂障碍.降低纸浆的漂白要求。有人提出白化菌预处理还能起到纤维改性的作用。  相似文献   
87.
88.
Discusses family systems, social support, operant conditioning, and cognitive-behavioral (CB) perspectives on the role of families in chronic illness and, specifically, chronic pain. A reformulated CB model is advanced that emphasizes patients' appraisals and interpretations of their spouses' responses to communications of pain. Using data from 148 married patients with chronic pain and their spouses, the quality of the marital relationship was specifically documented as a critical mediator. Relationships between spouses' responses to pain and important dimensions of the pain experience generally were present only among maritally satisfied couples. A CB model that integrates patients' appraisals, attributions, and expectancies with actual reinforcement contingencies appears to provide a reasonable way to conceptualize the role of spousal interactions and responses in perpetuation of pain, disability, and extent of suffering. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0 mm and an average caloric density of 611 cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.  相似文献   
90.
The present paper reported postmortem changes in muscle proteins on sea bream (Sparus aurata), during ice storage. The postmortem evolution of protein patterns in farmed sea bream was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimension electrophoresis (2DE). Matrix associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) was used for identification of proteins. Results of the bio-informatics analysis demonstrate that: (1) the normalized volume of skeletal alpha-actin and tropomyosin is not affected by the time of storage; (2) the normalized volumes of myosin light chain 3 and of major histocompatibility complex (MHC) class II beta1 increase; (3) the normalized volumes of Sec 13-like and parvalbumin significantly decrease.  相似文献   
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