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31.
本文阐述了蒸参水的化学成分。实验结果表明,蒸参水含有人参总皂甙(1.90g/L),多种氨基酸和多种维生素。 相似文献
32.
H. B. Stähelin 《Supportive care in cancer》1993,1(6):295-297
The potential of a high intake of fresh fruits and vegetables in cancer prevention is well established. Epidemiological studies support carotene, vitamins A, C, E and selenium as the active compounds. Antioxidant properties and direct effects (e.g. inhibition of N-nitrosamine formation or cell-to-cell interactions) are invoked. The role of other trace elements is less clear. The modulation of immune function by vitamins and trace elements remains important and affects survival. In established cancers, the site-specific differences in the diet/cancer relation require appropriate dietary changes, e.g. low fat (20% by energy) in breast cancer, or high vegetable or fruit intake in lung cancer. Single high-dose supplements (e.g. vitamin C) have proved to have no curative or life-prolonging effect. Chemotherapy and radiation increase the requirements for antioxidant compounds. Supplementation can diminish the damage induced by peroxidation. Carefully planned and monitored trials that establish the optimal intake of micronutrients as adjuvants in cancer patients are required.Presented as an invited lecture at the 4th International Symposium: Supportive Care in Cancer, St. Gallen, Switzerland, 24–27 February 1993 相似文献
33.
目的:建立HPLC法同时测定五维葡钙口服溶液中维生素B1,维生素B2,维生素B6(以下简称VB1,VB2,VB6)和烟酰胺的含量.方法:采用C18柱;以0.005 mol·L-1己烷磺酸钠与0.008 mol·L-1庚烷磺酸钠的1%乙酸溶液-甲醇(74:26)为流动相;检测波长276 nm;流速:1.0 mL· min-1.结果:VB1在36.30~84.70 μg·mL-1;VB2在7.26~ 16.94 μg·mL-1;VB6在10.93~25.51μg·mL-1与烟酰胺在36.20~84.48 μg·mL -1的范围内峰面积与浓度具有良好线性关系;VB1,VB2,VB6与烟酰胺的回收率依次为:99.78%,RSD=1.58%(n=6);99.80%,RSD=1.22% (n =6);100.07%,RSD=0.75% (n=6);99.62%,RSD=1.01% (n =6).结论:该方法准确,灵敏度高,重现性好. 相似文献
34.
35.
Ronco AM Llanos M Tamayo D Hirsch S 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2007,17(3):188-194
Background and aimsSeveral studies have shown the beneficial effects of folate treatment in improving cardiovascular function. However, the mechanisms involved have not been clearly identified. The aim of this study is to determine the effect of folates and vitamin B12 on endothelial vasoconstriction/vasodilatation parameters in cultured human endothelial cells incubated with human low density lipoproteins (LDL).Methods and resultsHuman umbilical vein endothelial cells (HUVEC) were extracted from recently delivered umbilical cords, cultured until confluence was achieved, and then incubated for 24 h with folic acid (FA), 5-methyltetrahydrofolic acid (5-MTHF) or vitamin B12 (B12) in the presence or absence of LDL that was isolated from healthy volunteers. Total nitrites (as a measure of nitric oxide production), thiobarbituric acid reactive species (TBARS, a parameter of lipid peroxidation), and endothelin-1 (ET-1) were determined in the incubation media. None of the vitamins, either in the presence or absence of LDL, was able to modify nitric oxide production by HUVEC. A significant reduction of ET-1 production was observed in LDL-treated cells. This effect was not modified by FA or B12; however, 5-MTHF caused a concentration-dependent increase on ET-1 production, an effect coincidental with reduced TBARS production.ConclusionsThis study demonstrates for the first time that 5-MTHF, but not FA or B12, increases ET-1 production in LDL-treated endothelial cells. Although this effect was associated with the antioxidant properties of this folate, our results show that additional specific mechanisms involving 5-MTHF-LDL interactions may be operating to regulate endothelial function. 相似文献
36.
Bruna Teixeira da Costa Glauber Rocha Lima Ara jo Ronaldo Teixeira da Silva J nior Luana Kauany de S Santos Vin cius Lima de Souza Gon alves Daniel Bastos Alves Lima Beatriz Rocha Cuzzuol Jonathan Santos Apolonio Lorena Sousa de Carvalho Hanna Santos Marques Camilo Santana Silva Isadora de Souza Barcelos M rcio Vasconcelos Oliveira Fabr cio Freire de Melo 《World Journal of Critical Care Medicine》2022,11(4):201-218
Recent research has demonstrated that critically ill patients with coronavirus disease 2019 (COVID-19) show significant immune system dysregulation. Due to that, some nutrients that influence immunomodulation have been suggested as a form of treatment against the infection. This review collected the information on the impact of vitamins on the prognosis of COVID-19, with the intention of facilitating treatment and prevention of the disease risk status in patients. The collected information was obtained using the PubMed electronic database by searching for articles that relate COVID-19 and the mechanisms/effects of the nutrients: Proteins, glucose, lipids, vitamin B12, vitamin D, calcium, iron, copper, zinc, and magnesium, including prospective, retrospective, and support articles. The findings reveal an optimal response related mainly to omega-3, eicosap entaenoic acid, docosahexaenoic acid, calcium, and iron that might represent benefits in the treatment of critically ill patients. However, nutrient supplementation should be done with caution due to the limited availability of randomized controlled studies. 相似文献
37.
调查了30例肺癌患者血清维生素A(VA)、β-胡萝卜素(CAR)、维生素C(VC)、维生素E(VE)及微量元素硒(Se)、锌(Zn)和铜(Cu)的含量。结果表明肺癌病人血清VA、CAR、VC、VE及Se、Zn水平显著低于对照组,血清Cu和Cu/Zn比值明显高于对照组。肺癌病人中吸烟者血清VC明显低于不吸烟者。3天膳食调查结果显示:肺癌病人每日CAR、膳食纤维、Zn及谷类、干豆类和蔬菜类食品摄入量显著低于对照组。 相似文献
38.
To develop tissue valves for prolonged use in the cardiovascular system, the complicated process of surface induced calcification must be better understood. Calcification was examined for 60 days on glutaraldehyde treated bovine pericardium (GABP) and enzyme extracted tissues fixed in glutaraldehyde (GATBP) incubated in metastable solutions of calcium phosphate, and the roles of aspirin and persantine in conjunction with vitamins C, B, or E, gentamycin (antibiotic), or pentothal sodium (anesthetic) in the medium were examined. Further, the diffusion of calcium across the GATBP was evaluated using a diffusion cell with 2 compartments. Pericardial calcification as also observed using scanning electron microscopy (SEM) techniques. It seems that the examined antiplatelet agents can modify the pericardial surfaces and subsequently their mineralization processes (GATBP, 31.7 μg/mg tissue; in the presence of 5 mg% vitamin C, 13.1 μg/mg tissue; in 1.5 mg% aspirin, 17.2 μg/ mg tissue; and 1 mg% gentamycin, 14.8 μg/mg tissue) on exposure with the metastable calcium phosphate solution for 60 days. In addition, these agents may modify calcium transport and interfere with the adsorption at the surface, hence reducing calcium nodulation on GATBP. Scanning electron micrographs also revealed a reduction in calcium deposition on the pericardium due to these antiplatelet agents. It may be hypothesized that the influx of calcium on GATBP may be due to the cellular components or the involvement of plasma proteins like the fibrinogen molecule. The exact mechanism of these changes in the calcification of the pericardium are still unknown. From these in vitro findings, it appears that a combined vitamin therapy with low doses of aspirin may be beneficial for platelet suppression and thereby for prevention of thrombosis and calcification. However, more in vivo studies are needed to develop applications. 相似文献
39.
完全肠道外营养添加维生素A、E、C对腹腔感染后抗氧化能力的影响 总被引:2,自引:1,他引:1
目的:观察完全肠道外营养(TPN)添加维生素A、E、C对腹腔感染后抗氧化能力的影响。方法:采用盲肠结扎加穿孔(CLP)模型,将SD大鼠随机分为对照组(CLP TPN)和治疗组(CLP TPN 维生素A、E、C),于0、1、3、5天观察血浆及肝组织中维生素含量、丙二醛(MDA)、还原型谷胱甘肽(GSH)的变化。结果:治疗组维生素A、E、C及GSH显著高于对照组,MDA明显低于对照组。结论:TPN添加维生素A、E、C能改善腹腔感染后机体的抗氧化能力,减轻脂质过氧化损伤。 相似文献
40.
Licinio J Milane M Thakur S Whelan F Yildiz BO Delibasi T de Miranda PB Ozata M Bolu E Depaoli A Wong ML 《Appetite》2007,49(3):594-599
In this report, we examine the effects of leptin on the intake of specific macro- and micronutrients in a female patient with leptin gene deficiency. The patient was studied off and on leptin at stable body weight, within the normal to mildly overweight range. The data were obtained by detailed dietary assessments, measuring dietary intakes by weighed food and fluid consumption records, and analyzed using nutrition analysis software. Overall, significant differences were found in the off versus on leptin treatment periods in the following categories: (i) macronutrients: kilocalories, protein, carbohydrates, monounsaturated fats, MFA 18:1 oleic and total fiber; (ii) vitamins: vitamin C, pyridoxine and pantothenic acid; (iii) minerals: potassium, magnesium, copper and chromium; and amino acids: threonine, lysine and histidine. The nutritional data from this study indicates a direct link between the effects of leptin and ingestion of several specific micronutrients. The mechanisms underlying these effects warrant further investigation and study. 相似文献