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排序方式: 共有1017条查询结果,搜索用时 46 毫秒
991.
992.
Douglas S Kalman Maria Heimer Anita Valdeon Howard Schwartz Eric Sheldon 《Nutrition journal》2008,7(1):3
Background
Intra-articular hyaluronic acid represents a substantive addition to the therapeutic armamentarium in knee osteoarthritis. We examined the effect of dietary supplementation with a natural extract of chicken combs with a high content of hyaluronic acid (60%) (Hyal-Joint®) (active test product, AP) on pain and quality of life in subjects with osteoarthritis of the knee.Methods
Twenty subjects aged ≥40 years with knee osteoarthritis (pain for at least 15 days in the previous month, symptoms present for ≥6 months, Kellgren/Lawrence score ≥2) participated in a randomized double-blind controlled trial. Ten subjects received AP (80 mg/day) and 10 placebo for 8 weeks. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and quality of life by the Short Form-36 (SF-36v2) were administered at baseline and after 4 and 8 weeks of treatment.Results
WOMAC pain (primary efficacy variable) was similar in both study groups (mean [SD]) with 6.6 (4.0) points in the AP group and 6.4 (2.7) in the placebo group (P = 0.943). As compared with baseline, subjects in both groups showed statistically significant improvements in WOMAC pain, stiffness, physical function subscales, and in the aggregate score, but the magnitude of changes was higher in the AP group for WOMAC physical function (-13.1 [12.0] vs. -10.1 [8.6], P = 0.575) and total symptoms (-18.6 [16.8] vs. -15.8 [11.4], P = 0.694). At 4 weeks, statistically significant mean changes compared with baseline were observed in the SF-36v2 scales of role-physical, bodily pain, social functioning and role-emotional among subjects in the AP group, and in physical functioning, bodily pain, and social functioning in the placebo group. At 8 weeks, changes were significant for role-physical, bodily pain, and physical component summary in the AP group, and for physical functioning and role-emotional in the placebo arm. Changes in bodily pain and social functioning were of greater magnitude in subjects given AP.Conclusion
This pilot clinical trial showed that daily supplementation with oral hyaluronic acid from a natural extract of chicken combs (Hyal-Joint®) was useful to enhance several markers of quality of life in adults with osteoarthritis of the knee. The results warrant further study in larger sample sizes.993.
Anita Pettersson Maria Zevenhoven Britt-Marie Steenari Lars-Erik Åmand 《Fuel》2008,87(15-16):3183-3193
In the important efforts to decrease the net CO2 emissions to the atmosphere, new, alternative fuels are being included in the fuel mixes used in utility boilers. However, these fuels have ash properties that are different from those of the traditionally used fuels and in some cases technical problems, such as ash fouling and corrosion occur due to this. Therefore, diagnostic and predictive methods are developed and used to avoid such problems. Determination of the chemical association forms of important elements, such as potassium and sodium, in the fuel by chemical fractionation is a method well defined for coal and biofuels, such as wood pellets, bark and forest residues. Chemical fractionation is a step by step leaching method extracting water soluble salts in the first step, ion exchangeable elements, such as organically associated sodium, calcium and magnesium in the second step and acid soluble compounds such as carbonates and sulfates in the third step. The solid residue fraction consists of silicates, oxides, sulfides and other minerals. The compound extracted in the two first steps is considered reactive in the combustion with a few exceptions. In this work, it has been applied to some waste fuels, i.e. sewage sludge, straw and refuse derived fuel (RDF), as well as to coal and wood. The present work also includes results from combustion tests in a fluidised bed boiler where three blends of the investigated fuels were used. The fractionation results for the fuel blends are weighted results of the fractionations of the pure fuels discussed above which are compared with fractionations of their corresponding fly ashes. The co-combustion strategy gave very good results in reducing ash problems. Possible chemical mechanisms involved are discussed in the article. 相似文献
994.
Levinson FJ Mehra S Levinson D Chauhan AK Koppe G Bence B Almedom AM 《Food and nutrition bulletin》2004,25(3):221-227
A follow-up study of malnutrition and its determinants among children 6 to 24 months of age was carried out in rural areas of Punjab State in India 30 years after the original study, and following a period of rapid economic growth. The original 1971 study had found a high prevalence of mortality and malnutrition and the worst gender difference in nutritional status ever recorded in an Indian study. The 2001 follow-up study found dramatic reductions in child mortality, child malnutrition, gender-based imbalances in child well-being and care, and family size, the result of participatory economic growth coupled with broad-based educational, health, and family-planning services. Despite overall improvements in caloric intake, however, 40% of lower-class children in 2001 were still consuming less than 50% of their caloric allowance. With minimal gender-based abortion and significantly reduced neglect and mortality offemale children, gender balance among children in this area of rural Punjab improved markedly over the 30-year period. 相似文献
995.
Imen Hamed Anita Nordeng Jakobsen Jørgen Lerfall 《Comprehensive Reviews in Food Science and Food Safety》2022,21(1):198-226
The global food processing industries represent a challenge and a risk to the environment due to the poor handling of residues, which are often discarded as waste without being used in further sidestreams. Although some part of this biomass is utilized, large quantities are, however, still under- or unutilized despite these byproducts being a rich resource of valuable compounds. These biowastes contain biopolymers and other compounds such as proteins, polysaccharides, lipids, pigments, micronutrients, and minerals with good nutritional values and active biological properties with applications in various fields including the development of sustainable food packaging. This review offers an update on the recent advancement of food byproducts recycling and upgrading toward the production of food packaging materials, which could be edible, (bio)degradable, and act as carriers of biobased active agents such as antimicrobials, antioxidants, flavoring additives, and health-promoting compounds. This should be a global initiative to promote the well-being of humans and achieve sustainability while respecting the ecological boundaries of our planet. Edible films and coatings formulations based on biopolymers and active compounds extracted from biowastes offer great opportunities to decrease the devastating overuse of plastic-based packaging. It has become evident that a transition from a fuel-based to a circular bio-based economy is potentially beneficial. Therefore, the exploitation of food discards within the context of a zero-waste biorefinery approach would improve waste management by minimizing its generation, reduce pollution, and provide value-added compounds. Most importantly, the development of edible packaging materials from food byproducts does not compete with food resources, and it also helps decrease our dependency on petroleum-based products. Practical Application Almost 99% of current plastics are petroleum-based, and their continuous use has been devastating to the planet as plastic-derived components have been detected in all trophic levels. Besides, the increasing amounts of food by-products are a socioeconomic and environmental challenge, and halving food loss and waste and turning it into valuable products has become necessary to achieve sustainability and economic circularity. The development of new packaging systems such as edible materials could be one of the solutions to limit the use of persistent plastics. Edible films and coatings by-products-based could also enhance food packaging performance due to their compounds' bioactivities. 相似文献
996.
Andrew John Forrest Paul Exley John Mayze Carl Paulo David Williams Anita Sikes Susan Elizabeth Poole 《Journal of food science》2014,79(10):C1877-C1885
Saddletail snapper (Lutjanus malabaricus) is a commercially significant tropical species in Australia and has been the subject of consumer complaints of extreme toughness in cooked fillets. Textural and biochemical analyses including collagen and hydroxylysyl pyridinoline (PYD) cross‐links concentrations were conducted on 101 commercially harvested Saddletail snapper to identify causes of toughness. Fish age was found to account for 75.6% of observed variation in cooked muscle texture (work done) of Saddletail snapper. A significant linear relationship (P < 0.001) between PYD content and cooked muscle texture was also identified accounting for 50.3% of observed variation. The concentration ratio of PYD to total collagen (TC) ranged from 0.04 to 0.38 mol PYD per mol of TC. Fish size was also found to be a poor indicator of fish age and therefore a poor indicator of the potential risk of toughness of the cooked muscle. 相似文献
997.
The presence of pharmaceuticals or their active metabolites in surface and ground waters has been recently reported as mainly due to an incomplete removal of these pollutants in sewage treatment plants (STP). Advanced oxidation processes may represent a suitable tool to reduce environmental release of these species by enhancing the global efficiency of reduction of pharmaceuticals in the municipal sewage plant effluents. The present work aims at assessing the kinetics of abatement from aqueous solutions of clofibric acid (a metabolite of the blood lipid regulator clofibrate) which has been found in surface, ground and drinking waters. Ozonation and hydrogen peroxide photolysis are capable of fast removal of this species in aqueous solution, with an almost complete conversion of the organic chlorine content into chloride ions for the investigated reaction conditions. A validation of assessed kinetics at clofibric acid concentrations as low as those found in STP effluents is presented for both systems. 相似文献
998.
Anita Klaus Maja Kozarski Miomir Niksic Dragica Jakovljevic Nina Todorovic Leo J.L.D. Van Griensven 《LWT》2011,44(10):2005-2011
Antioxidant properties of hot water extract (HWE), hot water extracted polysaccharides (HWP) and hot alkali extracted polysaccharides (HWAE) were obtained from fruiting bodies of the wild basidiomycete Schizophyllum commune. All extracts contained both α- and β-glucans as determined by Megazyme β-glucan assay kit. Glucose was found by TLC and NMR to be the prevalent monosaccharide in all extracts. Total phenol contents were in descending order of HWP ≈ HWE > HWAE. Median effective concentrations (EC50 values) of antioxidant activities were 8.3 ± 0.1, 6.9 ± 0.0 and 8.9 ± 0.1 mg/mL, and of the DPPH scavenging activity 0.8 ± 0.0, 0.6 ± 0.0 and 1.8 ± 0.0 mg/mL, for HWE, HWP and HWAE, respectively. EC50 values of reducing power were 7.6 ± 0.1, 7.9 ± 0.0 and 12.5 ± 0.1 mg/mL, whereas those of the chelating abilities on ferrous ions were 3.1 ± 0.0, 4.6 ± 0.1 and 4.9 ± 0.1 mg/mL. The EC50 values of the antioxidant activity, of the DPPH scavenging, and of the reducing power were correlated with total polysaccharide as well as with total phenol content. The antioxidant activities of all the extracts may be caused by both polysaccharides and polyphenols or by a complex of both. 相似文献
999.
Renouf LS Sheps S Hubley A Pick N Johansen D Tyndall MW 《Revue canadienne de la pratique et de la recherche en diététique》2012,73(3):128-133
Purpose: The association between medical, social, and nutritional factors and iron deficiency anemia was examined in adult women who had tested positive for human immunodeficiency virus (HIV) and were living in the Greater Vancouver Area. Methods: This was a cross-sectional observational study of 102 HIV-positive women, aged 19 or older, who were patients of one of three chosen community health clinics in Vancouver, British Columbia. Information on usual dietary intake and other nutrition-related factors was collected with a short diet survey, while medical information and laboratory data were obtained from each participant's medical chart. Results: Of the predictors studied, a CD4 cell count below 200 cells/μL, a regular menstrual pattern, and African ethnicity were associated with an increased risk of iron deficiency anemia. Dietary intake was not independently associated with iron status. Conclusions: Iron deficiency anemia in HIV-positive women has multifactorial and complicated causation, but is strongly associated with poorer immune status and greater menstrual losses. Health disparities in Aboriginal and African women may lead to a higher risk for iron deficiency anemia. Routine screening and ongoing nutrition education are necessary for the prevention and management of iron deficiency anemia. Further research into factors associated with iron deficiency anemia is essential to improve prevention and management efforts. 相似文献
1000.
In Gram-negative bacteria, the acyl-homoserine lactones (acyl-HSLs) are the main signaling substances employed in cell-to-cell communication systems. This paper describes the chemical characterization of acyl-HSLs produced by the worldwide-spread phytopathogen Pantoea ananatis (Serrano 1928) by using gas chromatography-electron impact mass spectrometry. The absolute configuration of the major identified substance, (S)-(−)-N-hexanoyl-HSL, was determined with gas chromatography-flame ionization detection with a chiral capillary column. Biological activities of extracts, fractions, and synthetic products were evaluated with the specific reporter Agrobacterium tumefaciensNTL4(pZLR4) in β-galactosidase expression assays. 相似文献