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21.
Judy A. Driskell Young-Nam Kim David W. Giraud Fayrene L. Hamouz Amilton S. de Mello Jr. Galen E. Erickson Chris R. Calkins 《Journal of food composition and analysis》2011,24(3):362-367
Selected vitamin (vitamin E, thiamin, riboflavin, niacin, vitamin B6, and vitamin B12) and mineral (calcium, phosphorus, magnesium, potassium, sulfur, iron, copper, zinc, manganese, and sodium) concentrations were determined for the value cuts—flat iron steaks (musculus infraspinatus) and petite tenders (musculus teres major) from cross-bred steers fed finishing rations containing 0% or 40% DM wet distiller's grains plus solubles (WDGS) with and without added daily supplemental vitamin E. The feeding treatment groups were: 0% WDGS with basal vitamin E (n = 6), 0% WDGS with supplemental vitamin E (500 IU/steer top-dressed daily) (n = 7), 40% WDGS with basal vitamin E (n = 8), and 40% WDGS with supplemental vitamin E (n = 8). Few differences in micronutrient concentrations were observed in either cut by treatment groups. Feeding steers diets containing 40% WDGS decreased vitamin B12 and increased sodium concentrations in flat iron steaks and increased thiamin and decreased manganese concentrations in petite tenders. Significant differences in α-tocopherol concentrations in both cuts were observed by vitamin E grouping. Several significant differences were observed by cut. Uncooked flat iron steaks and petite tenders from these steers are rich sources of vitamin B12, zinc, and sometimes phosphorus, good sources of riboflavin, niacin, vitamin B6, and iron, and low in sodium. 相似文献
22.
目的对四维钙片中的维生素C(VitC)、维生素B1(vitB1)及维生素B2(VitB2)进行含量测定。方法采用反相高效液相色谱法,使用Zorbax Eclipse XDB—C8柱(150mm×4.6mm,5μm),流动相为0.05%乙酸溶液(含0.005mol/L己烷磺酸钠、1.3%三乙胺,用冰醋酸调节pH值至3.5)-甲醇(90:lO),检测波长为254nm。结果VitC,VitB1,,VitB2质量浓度分别在7~60μg/mL,1~10μg/mL,1~10μg/mL范围内与峰面积线性关系良好,r分别为0.9998,0.9997,0.9998(n=8);平均回收率分别为100.3%,99.1%,98.5%,RSD分别为1.2%.1.5%.1.6%(n=9)。结论该方法准确、简单,能够有效控制制剂的质量。 相似文献
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目的:了解维生素加早期干预对早产低出生体重儿智能发育的影响。方法:选择2001年12月~2003年12月出生存活的早产儿160例随机分为维生素加干预组和早产对照组,同时收集正常出生体重儿80例为足月对照组。干预组在新生儿期即给予抚触、听背景音乐、看红球等刺激,指导家长在家中进行视听、感知觉及运动方面的干预训练,并于生后2周口服小施尔康滴剂1.0ml/d共8周。对所有儿童每月进行随访,小儿1岁时用婴幼儿智能发育量表Gesell(中国标准化)测定其发育商(Development Quotient DQ)。结果:智能测试综合指标:早产治疗组与早产对照组相比具非常显著性差异(F=9.28,P=0.00);早产治疗组与足月对照组相比无显著性差异(F=0.56,P=0.70);早产对照组与足月对照组相比具非常显著性差异(F=9.96,P=0.00)。维生素加早期干预组在运动能、应物能、言语能、应人能等能区与早产对照组相比,有显著性差异,与正常出生体重儿相比无差异。结论:维生素加早期干预对早产低出生体重儿在婴儿期智能发育方面有良好的促进作用。 相似文献
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26.
The purpose of this study was to investigate the implications of dietary intake and the level of plasma antioxidant, lipid peroxidation, and antioxidant capacity in Korean women with cervical intraepithelial neoplasia (CIN). From October 2002 to March 2003, 58 patients diagnosed with CIN (confirmed with colposcopy directed biopsy) and 86 patients without any cervical disease as control group were enrolled in the study at the Department of Gynecology cancer center at Samsung Cheil Hospital. The intake of antioxidant vitamins in both groups exceeded the amount recommended by the Korea RDA, 7th edition. The plasma concentration of Vitamin C was significantly lower in the CIN group (0.36 mg/dL) than in the control group (0.48 mg/dL) (p<0.05). The two groups showed similar plasma concentrations of beta-carotene, alpha-tocopherol, and retinol. The average concentration of malondialdehydes in the CIN group, 7.23 mmol/mL, was significantly higher than in the control group, 5.18 mmol/mL (p<0.01). The total radical trapping antioxidant potential concentration of plasma was significantly higher in the CIN group (1.15 mM) than in the control group (1.25 mM) (p<0.05). These results suggest that there is a possible correlation between cervical intraepithelial neoplastic processes and changes in the plasma antioxidative system. 相似文献
27.
Antioxidative vitamins decrease cytotoxicity of HEMA and TEGDMA in cultured cell lines 总被引:3,自引:0,他引:3
OBJECTIVES AND METHODS: In a previous study it was postulated that toxicity of 2-hydroxyethylmethacrylate (HEMA) and triethleneglycoldimethacrylate (TEGDMA) is based on oxidative metabolites. In this study the influence of antioxidative vitamins (including uric acid) on the toxicity of HEMA or TEGDMA was tested. Toxicity of HEMA and TEGDMA was determined in rat alveolar epithelial L2, human malignant A549, and human fibroblast-like 11Lu cells by inhibition of methionine incorporation (as a marker of protein synthesis inhibition) and by determination of glutathione depletion, as well as by measurement of GSSG increase. RESULTS: Toxicity of the composite components HEMA and TEGDMA was demonstrated by GSH depletion as the most sensitive method. Five hundred micromoles per litre Vitamin C or 250 micromol/l Vitamin E were mostly able to decrease toxicity of HEMA and TEGDMA in the cell lines tested. In addition, 250 micromol/l Vitamin A was only effective in L2 cells impairing HEMA toxicity and 250 micromol/l uric acid impairing TEGDMA toxicity as assessed by decreased GSH depletion. In A549 cells only methionine incorporation inhibition but not GSH depletion was significantly affected. By contrast, in 11Lu cells methionine incorporation inhibition was not significantly changed, but GSH depletion was. CONCLUSIONS: The postulated mechanism of HEMA or TEGDMA toxicity based on radical metabolites is supported by the effectivity of the antioxidative substances tested in mitigating toxicity and by the greater susceptibility of the glutathione redox system as compared to protein synthesis inhibition in assessing toxicity. 相似文献
28.
Using the comet assay, we showed that vanadyl sulfate induced DNA damage in human normal lymphocytes and in HeLa cells. Vanadyl at 0.5 and 1 mM produced DNA single- and double-strand breaks (SSBs and DSBs) in lymphocytes, whereas in HeLa cells we observed only SSBs. Post-treatment of vanadyl-damaged DNA from lymphocytes with formamidopyrimidine-DNA glycosylase (Fpg), an enzyme recognizing oxidized purines, gave rise to a significant increase in the extent of DNA damage. A similar effect was observed in HeLa cells, but, using endonuclease III, we also detected oxidized pyrimidines in DNA of these cells. There were no differences in the extent of DNA damage in the lymphocytes and HeLa cells in the pH >13 and pH 12.1 conditions of the comet assay, which indicates that strand breaks, and not alkali-labile sites, contributed to the measured DNA damage. Study of DNA repair, determined in the comet assay as an ability of cells to decrease of DNA damage, revealed that HeLa cells retained the ability to repair vanadyl-damaged DNA induced at a ten-fold higher concentration than that in lymphocytes. Incubation of the cells with nitrone spin traps DMPO, POBN and PBN decreased the extent of DNA damage, which might follow from the production of free radicals by vanadyl sulfate. The presence of vitamins A, C or E caused an increase of DNA damage in HeLa cells whereas in lymphocytes such an increase was observed only for vitamin C. Our data indicate that vanadyl sulfate can be genotoxic for normal and cancer cells. It seems to have a higher genotoxic potential for cancer cells than for normal lymphocytes. Vitamins A, C and E can increase this potential. 相似文献
29.
van Herpen-Broekmans WM Klöpping-Ketelaars IA Bots ML Kluft C Princen H Hendriks HF Tijburg LB van Poppel G Kardinaal AF 《European journal of epidemiology》2004,19(10):915-921
Background: Endothelial cell dysfunction may be related to an increase in cellular oxidative stress. Carotenoids and vitamins could have an antioxidant-mediated tempering influence on endothelial function and inflammation, thereby reducing the risk of atherosclerosis. Methods: We measured serum carotenoids, $\ralpha$-tocopherol and Vitamin C concentrations in 379 subjects sampled from the general population. High-sensitive C-reactive protein (CRP), fibrinogen (Fbg) and leukocytes were measured as markers of inflammation. Furthermore, soluble intercellular adhesion molecule-1 (sICAM-1) and flow-mediated vasodilation (FMD; n=165) were measured as markers of endothelial function. Relationships between serum carotenoids and vitamins and markers of endothelial function and inflammation were analysed after adjustment for confounding. Results: In the total study group, lutein and lycopene were inversely related to sICAM-1 with regression-coefficients of –0.38 $\pm$ 0.19 (p=0.04) and –0.16 $\pm$ 0.08 (p=0.04) per 1 $\rmu$mol/l, respectively. $\rbeta$-Carotene was inverse related to leukocytes (–0.23 $\pm$ 0.07; p=0.007) and CRP (–1.09 ± 0.30; p=0.0003) per 1 $\rmu$mol/l. Vitamin C was inverse related to CRP (–0.01 $\pm$ 0.005; p=0.04) per 1 $\rmu$mol/l, whereas $\ralpha$-tocopherol was positively related to CRP (0.03 $\pm$ 0.01; p=0.02) per 1 $\rmu$/l. Zeaxanthin was inversely related to FMD (31.2 $\pm$ 15.3; p=0.04) per 1 $\rmu$mol/l. Conclusion: The inverse relations between carotenoids, Vitamin C and sICAM-1, CRP and leukocytes may help to explain the possible protective effect of carotenoids and Vitamin C on atherosclerosis through an influence on inflammatory processes and endothelial function. 相似文献
30.
The oxidative modification hypothesis postulates that oxidative stress is one of the major factors in aging and the development of age-related disorders, including cardiovascular diseases. In this scenario, the oxidative modification of lipids, proteins and nucleic acids in vascular walls contributes to the etiology of cardiovascular disease, implying that consumption or therapeutic use of antioxidants could prevent the onset of such pathological disorders. Because of this, a number of studies have been conducted to address the question of whether cardiovascular diseases can be modulated by antioxidant treatment or consumption. Although some of the earliest data, collected in animal studies and epidemiologic studies have shown a measure of success, numerous clinical trials indicate that this approach is of minimal or no benefit. These conclusions represent a challenge to design more sensitive antioxidant trials in order to confirm or alter these conclusions. The focus of this review is on the benefits and disadvantages associated with the use of antioxidants, such as vitamins C and E, polyphenols, or antioxidant therapies, including hormone replacement therapy and iron reduction therapy, on overall vascular health. 相似文献