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排序方式: 共有522条查询结果,搜索用时 31 毫秒
141.
富含硒玉米对低硒大鼠血硒和GSH-Px活性的影响 总被引:1,自引:0,他引:1
为了研究富含硒玉米对低硒粮饲料喂养大鼠血硒状态的影响 ,观察了补充富含硒玉米或亚硒酸钠时和停止补硒后大鼠血硒水平和谷胱甘肽过氧化物酶 ( GSH- Px)活性的变化。结果显示 :1两种补硒形式均可有效地增高血浆、红细胞的硒水平和红细胞的 GSH- Px活性 ;2富含硒玉米增高和维持血浆和红细胞硒水平作用与亚硒酸钠相同 ;3富含硒玉米升高红细胞 GSH- Px活性的作用低于亚硒酸钠 ,但停止补硒后两者维持 GSH- Px活性作用相似。表明富含硒玉米能有效地改善低硒大鼠的血硒状态 相似文献
142.
Farsi DA Harris CS Reid L Bennett SA Haddad PS Martineau LC Arnason JT 《Phytotherapy research : PTR》2008,22(1):108-112
Non-enzymatic glycation and the accumulation of advanced glycation end products (AGEs) are associated with various disease states, including complications of diabetes and aging. Secondary metabolites from several plant species are known to inhibit non-enzymatic glycation and the formation of AGEs, including flavonoids found in the style (silk) of Zea mays (maize). Thirteen modern maize inbreds and one land race were tested for in vitro inhibition of non-enzymatic glycation of bovine serum albumin. Many of the tested extracts exhibited inhibitory activity, in particular the newest inbreds, which were bred for resistance to gibberella ear rot (Fusarium graminearum) and common smut (Ustilago maydis). The most active maize genotype (CO441), displaying an IC50 of 9.5 microg/mL, was more effective than aminoguanidine, a known inhibitor of glycation. Zapalote chico, a land race with high maysin content, showed only moderate inhibitory activity compared with the modern maize genotypes. Antiglycation activity was highly correlated with the total phenolic content of silk extracts and mildly correlated with resistance to certain fungal infections. The results identify modern resistant and high phenolic maize inbreds as promising candidates for the development of natural AGE inhibitors for the prevention and treatment of diabetic complications and the degenerative effects of aging. 相似文献
143.
Sara Petersson Elena Philippou Carrie Rodomar Elena Nikiphorou 《Autoimmunity reviews》2018,17(11):1105-1114
The impact of dietary interventions such as specific types of diet or nutritional supplements in rheumatoid arthritis (RA) has been subject to increased attention in recent years. The recognition of the unmet need to better understand the effects of specific dietary interventions on disease outcomes in RA, along with the growing patient interest on lifestyle interventions beyond pharmacotherapy, have informed the undertaking of this narrative literature review. The benefits of the Mediterranean Diet (MD) have been shown in various studies, although only a limited number of trials focus specifically on RA. Based on the studies reviewed, the MD may provide benefits in reducing pain and swollen and tender joints in RA patients. There is more and better evidence that n-3 polyunsaturated fat (PUFA) supplementation has the potential to reduce inflammation and provide clinical benefit, possibly slowing progression to pharmacotherapy. Yet, many of these studies to date are limited in their methodology; this being partly a reflection of the complexity of the research questions being addressed. Consequently, the conclusions that can be robustly drawn from their results are restricted. With a focus on clinical trials on the MD and fish oil supplementation, this review critically appraises the evidence, discussing the findings of studies in the wider context of impact on RA outcomes, methodological challenges, and practical points to consider as part of the routine care of RA patients. 相似文献
144.
目的:研制玉米须多糖胶囊。方法:采用单因素试验筛选玉米须多糖胶囊的制备所适宜的润湿剂浓度、用量,干燥温度、时间,并确定颗粒的临界相对湿度,建立含量测定方法。结果:所制备胶囊的制备工艺简单、质量稳定。结论:建立的玉米须胶囊的制备方法,可以减少服用剂量、促进玉米须资源的利用。 相似文献
145.
Julio Navascués Carmen González-Ramos Ignacio S. Alvarez Lucía Rodríguez-Gallardo Gervasio Martín-Partido 《Anatomy and embryology》1989,180(4):343-351
Summary In addition to mitoses of neuroepithelial cells at the ventricular surface of the chick embryo optic stalk, mitoses in nonventricular stalk zones begin to be observed from stage 19 on. These latter represent the division phase of glioblasts detached from the ventricular surface. Thus, the topographical location of mitotic cells could be considered a morphological marker of neuroepithelial and glioblast populations in the optic stalk. Quantitative analysis of ventricular (VMCs) and extraventricular (EMCs) mitotic cells revealed that the total number of VMCs decreases through the developmental stages studied, while the number of EMCs simultaneously increases exponentially. These results suggest that the glioblast population arises from both division of the early glioblasts and progressive transformation of neuroepithelial cells.The first EMCs in the ventral region of the stalk wall are observed in stage 19, previous to the stages in which the first EMCs appear in the dorsal region. Moreover, EMCs are much more numerous in the ventral than in the dorsal stalk wall in all stages analysed. Keeping in mind that the invasion of the stalk by optic fibre fascicles occurs essentially in the ventral region, these results suggest that EMCs are strongly related to axon fascicle outgrowth in the stalk.Cell division features are different in neuroepithelial cell and glioblast populations, as the proportions of the mitotic phases differ in VMCs and EMCs. In addition, the patterns of mitotic spindle orientation in VMCs and EMCs are also different. In the former, orientations are predominantly longitudinal parallel and transverse parallel, with a smaller proportion of radial mitoses, which are slightly more frequent through stages 23 to 28 than in earlier development. In the EMCs, radial and longitudinal parallel spindle orientations are the most frequent, the proportion of mitoses with transverse parallel orientation being very low through stages 24 to 28. The significance of these results is discussed with reference to stalk developmental mechanisms. 相似文献
146.
147.
研究目的探讨玉米花粉山楂口服液对大白鼠血液流变学的影响。研究背景玉米花粉具有明显的降血脂和降低血液粘度的作用,已被用于治疗高脂血症和冠心病,山楂具有消积和活血化瘀等功能,两者联合使用,对降血脂会更加明显。为此我们作了进一步的探讨。研究方法通过建立高脂动物模型,观察补充喂食玉米花粉山楂口服液对高脂动物血液流变学8项指标的影响。结果玉米花粉山楂口服液可明显降低血液粘度(P<0.05)。除血浆比粘度外,玉米花粉山植口服液在改变血液流变学万面优于安妥明组(p<0.05或p<0.01)。结论玉米花粉山植口服液具有降低血液粘度的作用,提示此药有可能成为较理想的降血脂药物。 相似文献
148.
10g玉米粉在500ml的三角瓶中与200ml Na_2HPO_4/KH_2PO_4缓冲液(1/15M,pH6.81,含草酸铵0.6%,MgSO_4 0.01%,FeSO_4 0.002%)混匀,在接种热带假丝酵母B020的同时加入α-淀粉酶1.5g,在摇床中30℃,120r/min通气培养3天,蛋白质含量从8.4%提高到23.4%(P<0.005);硫胺素含量从0.383mg/100g提高到0.767mg/100g(P<0.005);核黄素含量从0.124 mg/100g提高到0.233mg/100g(P<0.05)。蛋白质中赖氨酸含量从32.1mg/g提高到67.5mg/g;色氨酸含量从8.5mg/g提高到12.7mg/g。 相似文献
149.
J. Scibilia E. A. Pastorello G. Zisa A. Ottolenghi B. Ballmer‐Weber V. Pravettoni E. Scovena A. Robino C. Ortolani 《Clinical and experimental allergy》2008,38(12):1943-1949
Background Maize allergy is not very common especially in Europe. The number of studies that address IgE mediated maize allergy is all too few. Objective Evaluate subjects with a history of maize allergy by double‐blind, placebo‐controlled food challenge; identify the spectrum of symptoms manifested during challenge; determine the lowest provocation dose (PD) during challenge; determine the performance characteristics of maize skin prick test and specific IgE. Methods Twenty‐seven patients with a history of maize allergy were enrolled to be evaluated by skin test, specific IgE and double‐blind placebo‐controlled maize challenge. Results Forty‐eight percent of the patients were challenge positive. PD range was 0.1–25 g. Fifty‐four percent of the maize allergic subjects had a PD that was 2.5 g; two subjects reacted to 100 mg of maize. Comparison of maize specific IgE levels and skin test results to the challenge results revealed the following (specific IgE level/skin testing): sensitivity 1.00/0.846, specificity 0.077/0.384, positive predictive value 0.520/0.579, and negative predictive value 1.00/0.714. Conclusion Maize is a cause of IgE‐mediated allergic reactions to foods in adults and children. Nearly half of the subjects recruited were confirmed by challenge to be allergic to maize. Twenty‐three percent of the positive challenge patients manifested symptoms that involved two organ systems, thus fulfilling the criteria for maize induced anaphylaxis. Maize is allergenic and can pose a risk for symptomatic food allergy at a dose of 100 mg. 相似文献
150.
Susan A MacKenzie Ian Lamb Jean Schmidt Lora Deege Michael J Morrisey Marc Harper Raymond J Layton Lee M Prochaska Craig Sanders Mary Locke Joel L Mattsson Angel Fuentes Bryan Delaney 《Food and chemical toxicology》2007,45(4):551-562
Maize line 1507, containing event DAS-Ø15Ø7-1 (1507), is a genetically modified (GM) maize plant that expresses the cry1F gene from Bacillus thuringiensis (Bt) sbsp. aizawai and the phosphinothricin-N-acetyltransferase (pat) gene from Streptomyces viridochromogenes throughout the plant including in the grain expression of the Cry1F protein confers in planta resistance to the European corn borer (ECB; Ostrinia nubilalis Hübner: Crambidae) and other lepidopteran pests. Expression of the PAT protein confers tolerance to the herbicidal active ingredient glufosinate–ammonium. The current study evaluated the nutritional performance of rats fed diets containing 1507 maize grain in a subchronic rodent feeding study. The grains in this study, 1507, its near-isogenic control (33P66), and a non-GM commercial hybrid (33J56) contained similar amounts of proximates, amino acids, minerals, anti-nutrients, and secondary metabolites. The subchronic feeding study compared standard toxicology response variables in rats fed diets containing 1507 maize grain with those in rats fed diets containing non-GM maize grains. All diets were prepared according to the specifications of PMI® Nutrition International, LLC Certified Rodent LabDiet® 5002 (PMI® 5002). Diets were fed ad libitum to Sprague–Dawley rats for approximately 90 days. In-life response variables included indicators of dietary performance and weekly evaluations for clinical signs of toxicity. No toxicologically significant differences were observed in the nutritional performance variables, clinical and neurobehavioral signs, ophthalmology, clinical pathology (hematology, clinical chemistry, coagulation, and urinalysis), organ weights, and gross and microscopic pathology between any pair of treatment groups. These results demonstrate that 1507 maize grain is as safe and as nutritious as non-GM maize grain. 相似文献