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排序方式: 共有772条查询结果,搜索用时 15 毫秒
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Anna F. Horn Nina S. Nielsen Charlotte Jacobsen 《International Journal of Food Science & Technology》2012,47(5):1097-1108
The objective of this study was to investigate the protective effect of five different emulsifiers on iron‐mediated lipid oxidation in 70% fish oil‐in‐water emulsions. The emulsifiers were either based on protein (whey protein isolate and sodium caseinate) or based on phospholipid (soy lecithin and two milk phospholipids with different phospholipid contents, MPL20 and MPL75). Lipid oxidation was studied at pH 4.5 and 7.0, and results were compared to lipid oxidation in neat fish oil. Results showed that all emulsions oxidised more than neat oil. Furthermore, emulsions prepared with proteins oxidised more at low pH than at high pH, and casein emulsions oxidised the least (Peroxide value (PV) at day 7 was 0.5–0.7 meq kg?1). Among emulsions prepared with phospholipids, emulsions with MPL75 were the most oxidised followed by emulsions prepared with lecithin and MPL20. Thus, PV in MPL75 emulsions was 5.0–5.5 meq kg?1 at day 7 compared with 0.9–1.9 meq kg?1 in MPL20 emulsions. 相似文献
23.
ABSTRACT: BACKGROUND: Weight loss is often difficult to achieve in individuals with type 2 diabetes and anti-obesity drugs are often advocated to support dietary intervention. Despite the extensive use of centrally acting anti-obesity drugs, there is little evidence of how they affect dietary composition. We investigated changes in energy intake and dietary composition of macro- and micronutrients following therapy with the endocannabinoid receptor blocker, rimonabant. METHODS: 20 obese patients with type 2 diabetes were studied before and after 6 months dietary intervention with rimonabant. Dietary intervention was supervised by a diabetes dietician. Five-day food diaries were completed at baseline and at 6 months and dietary analysis was performed using computer software (Dietplan 6). RESULTS: After 6 months, (compared with baseline) there were reductions in weight (107+/-21Kg versus 112+/-21, p<0.001, 4% body weight reduction), and improvements in HbA1c (7.4+/-1.7 versus 8.0+/-1.6%, p<0.05) and HDL cholesterol. Intake of energy (1589+/-384 versus 2225+/-1109kcal, p<0.01), carbohydrate (199+/-74 versus 273+/-194g, p<0.05), protein (78+/-23 versus 98+/-36g, p<0.05), fats (55+/-18 versus 84+/-39g, p<0.01) and several micronutrients were reduced. However, relative macronutrient composition of the diet was unchanged. Improvement in blood glucose was strongly correlated with a reduction in carbohydrate intake (r = 0.76, p<0.001). CONCLUSIONS: In obese patients with type 2 diabetes, rimonabant in combination with dietary intervention led to reduced intake of energy and most macronutrients. Despite this, macronutrient composition of the diet was unaltered. These dietary changes (especially carbohydrate restriction) were associated with weight loss and favourable metabolic effects. 相似文献
24.
Hwa Jung Kim Jeongah Ko Charlotte Storni Hong Ji Song Young Gyu Cho 《Journal of Functional Foods》2012,4(1):287-293
Overweight and obesity have become a global epidemic and they may impair health. Traditional use and growing evidence indicate that mate (Ilex paraguariensis A. St.-Hil.) may be helpful in losing excessive weight and fat. The present randomized, double-blind, placebo-controlled study evaluated efficacy and safety of an extract from green mate in 60 overweight subjects aged 20–39 years during 6-weeks. Body composition was measured by Dual-Energy X-ray Absorptiometry (DEXA) at baseline and after 6 weeks. Body weight, body mass index (BMI), waist circumference (WC) and various safety parameters were monitored. After 6 weeks, subjects taking mate experienced a significantly greater reduction of percent of body fat (?0.3% vs. +0.6%, p = 0.04) and fat mass (?0.5 kg vs. +0.2 kg, p = 0.04) than placebo. No significant differences were observed in other measurements. No adverse events occurred and all safety parameters were within normal ranges during the study in both groups. Thus, taking green mate extract reduced body fat after 6 weeks, while the treatment was safe and well tolerated. 相似文献
25.
This study describes the Danish publication award system (BFI), investigates whether its built-in incentives have had an effect on publication behavior at the University of Southern Denmark, and discusses the possible future implications on researcher incentives should universities wish to measure BFI on the individual level. We analyzed publication data from the university CRIS system (Pure) and from SciVal. Several studies indicate that co-authored scholarly journal articles attract more citations than single author articles. The reason for this are not clear, however, research collaboration across institutions and countries is commonly accepted in the research community and among university managements as one way of increasing the researcher’s and institution’s reputation and impact. The BFI system is designed to award scholarly publication activity at Danish universities, especially publication in international journals of high status. However, we find that the built-in incentives leave the researcher and his or her institution with a dilemma: If the researchers optimize their performance by forming author groups with external collaborators, the optimal way of doing so for the researchers is not the optimal way seen from the perspective of the university. Our analysis shows that the typical article has 6.5 authors, two of which are internal, and that this has remained stable since the introduction of the BFI. However, there is variation across the disciplines. While ‘the Arts and Humanities’ and ‘the Social Sciences’ seem to compose author groups in a way which does not optimize the performance of the institution, both ‘Health’ and ‘the Natural Sciences’ seem to optimize according to criteria other than those specified in the BFI. 相似文献
26.
Charlotte Besser Christoph SchneidhoferNicole Dörr Franz Novotny-FarkasGünter Allmaier 《Tribology International》2012,46(1):174-182
The effect of ethanol and its combustion products on the lubrication system is not very well understood. In this paper, a novel lab-based artificial ageing method for the evaluation of engine oils for bio-fuelled automotives and the results thereof are presented. Artificial ageing of three fully formulated engine oils with addition of ethanol, acetaldehyde, and acetic acid was carried out. The oil formulations chosen represent a consequent series of optimisation steps based on the engine oil performance in terms of preservation of typical oil parameters, e.g. base reserve and oxidation, observed during the artificial ageing procedure. It was shown that ethanol as well as acetaldehyde has almost no effect on the oil degradation especially in the case that advanced additive technology was used. On the contrary, acetic acid significantly affected the formulated oil showing influence on the detergent chemistry and even caused sludge formation. The use of the novel artificial ageing method proved to clearly differentiate the impact of the respective compounds added with the possibility to simulate enhanced stress conditions without the need of time-consuming and expensive engine bench tests. Hence, the novel setup offers valuable input for the formulation and the pre-selection of future engine oils suitable for bio-fuel. 相似文献
27.
Antioxidant Activity of Seaweed Extracts: In Vitro Assays,Evaluation in 5 % Fish Oil‐in‐Water Emulsions and Characterization 下载免费PDF全文
K. H. Sabeena Farvin Charlotte Jacobsen 《Journal of the American Oil Chemists' Society》2015,92(4):571-587
In this study the antioxidant activity of absolute ethanol, 50 % ethanol and water extracts of two species of seaweeds, namely Fucus serratus and Polysiphonia fucoides, were evaluated both in in vitro assays and in 5 % fish oil‐in‐water (o/w) emulsions. The 50 % ethanolic extracts of P. fucoides showed higher antioxidant activity both in in vitro assays and in 5 % oil‐in‐water emulsion in the presence or absence of iron. In spite of the higher phenolic content and very good antioxidant activity in some of the in vitro assays, the absolute ethanol extracts of both the species showed a pro‐oxidative tendency in 5 % fish oil‐in‐water emulsion in the presence or absence of iron. In order to investigate the reason for the higher antioxidant activity of 50 % ethanolic extracts of P. fucoides, these extracts were further fractionated into polyphenol‐rich, protein‐rich, polysaccharide‐rich and low‐molecular‐weight fractions. These fractions were tested both in in vitro and in 5 % oil‐in‐water emulsions. The results of the present study showed that the main effect was due to the phenolic compounds. In conclusion, the 50 % ethanolic extracts of P. fucoides can be a potential source of natural antioxidants as these extracts have antioxidant activities similar to those of synthetic antioxidants such as BHT. 相似文献
28.
ABSTRACTThis paper examines the performance of environmental strategies in seven recently constructed or refurbished university buildings in the UK. These buildings contain a range of administrative spaces, classrooms, libraries and studios, reflecting their often complex, multi-use, heterogeneous nature. The key features of each environmental strategy are described (including passive, mixed-mode or active systems), in the context of the occupants and spaces they serve and the level of interaction that they afford. Energy performance and occupant thermal comfort (assessed by user surveys) are analysed and compared with studies of other non-domestic buildings, which have typically focused on more predictable single administrative uses (e.g. government offices), and unusually effective operation scenarios (e.g. continuous monitoring by expert building managers). The paper concludes by examining two of the case studies that reflect an increasingly common model of ‘flexible’ environmental design in more detail, identifying key features of the strategies for each building that have had a significant impact on their performance. The design assumptions leading to these features will be explored, and key lessons identified, contributing towards the development of a more robust evidential basis for choosing appropriate environmental strategies for university and other non-domestic buildings in the UK. 相似文献
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30.
Araceli Diez-Fraile Joke De Ceulaer Charlotte Derpoorter Christophe Spaas Tom De Backer Philippe Lamoral Johan Abeloos Tim Lammens 《International journal of molecular sciences》2022,23(5)
The 5-year relative survival for patients with head and neck cancer, the seventh most common form of cancer worldwide, was reported as 67% in developed countries in the second decade of the new millennium. Although surgery, radiotherapy, chemotherapy, or combined treatment often elicits an initial satisfactory response, relapses are frequently observed within two years. Current surveillance methods, including clinical exams and imaging evaluations, have not unambiguously demonstrated a survival benefit, most probably due to a lack of sensitivity in detecting very early recurrence. Recently, liquid biopsy monitoring of the molecular fingerprint of head and neck squamous cell carcinoma has been proposed and investigated as a strategy for longitudinal patient care. These innovative methods offer rapid, safe, and highly informative genetic analysis that can identify small tumors not yet visible by advanced imaging techniques, thus potentially shortening the time to treatment and improving survival outcomes. In this review, we provide insights into the available evidence that the molecular tumor fingerprint can be used in the surveillance of head and neck squamous cell carcinoma. Challenges to overcome, prior to clinical implementation, are also discussed. 相似文献