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1.
All commercial corn oil is obtained by pressing corn germ and/or extracting the germ with hexane. In the current study, six types of corn oil were prepared by extracting corn germ, corn fiber and ground corn, each with hexane or with ethanol. The levels of lutein, zeaxanthin and other carotenoids were quantitatively analyzed in the six corn oils. The levels of lutein + zeaxanthin in the oil ranged from 2.3 μg/g for hexane-extracted corn germ oil to 220.9 μg/g for ethanol-extracted ground corn oil. These results indicate that a diet that includes 30 g (~2 tbsp) per day of the unrefined corn oil obtained by extracting ground corn with ethanol would provide ~6 mg of lutein + zeaxanthin, the daily dosage that is currently considered to be necessary to slow the progression of age-related macular degeneration. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture.  相似文献   
2.
We used psychophysiological technology to examine the effect of an oral supplement, a combination of lutein, zeaxanthin and blackcurrant extract (LUT), on visual fatigue, within the context of a randomized, double-blind, placebo-controlled cross-over trial. The LUT supplement and placebo samples were randomly assigned to thirteen participants, who took the samples for two LUT (and vice versa) for another 2 week. Each participant completed visual proof reading tasks for 2 h during each of four testing sessions. Saccade tests were administered before and after the proof reading task, during which the participants moved their eyes back and forth between two targets positioned in the center of two checkerboards. We recorded EEG, EOG, heart rate, and facial muscle potential/performance during the saccade tests. Blood pressure was measured and subjective fatigue and stress scores were collected before and after the proof reading task. We averaged EEG starting at saccade offset in order to analyze eye fixation related potentials (EFRP). Our results suggested that the proof reading task induced visual fatigue. An analysis of EFRP and other psychophysiological data revealed significant differences between the LUT and placebo conditions. These results suggest that supplementation with LUT could help to reduce symptoms of visual fatigue.  相似文献   
3.
叶黄素的热解产物分析   总被引:4,自引:0,他引:4  
为研究叶黄素对卷烟燃吸品质的影响,分别在300、600、900℃和氮气、10%氧气 90%氮气、大气环境中进行了叶黄素热解试验,热解产物经固相微萃取后进行GC/MS分析,并用叶黄素进行了卷烟加香试验。结果表明:①在所试验的温度和氛围中,叶黄素的裂解产物主要是甲苯、对-二甲苯、1,2-二氢-1,1,6-三甲基-萘和2,7-二甲基萘等,另外还有少量的氧化异佛尔酮、巨豆三烯酮、醛和烯烃类物质等;②叶黄素裂解产物的种类和相对含量都随着裂解温度的变化而变化,而裂解氛围则影响不大;③添加叶黄素的卷烟烟气香气略增加,但其杂气、刺激性都明显增大,余味变差。因此,添加叶黄素不利于卷烟抽吸品质的提高。  相似文献   
4.
Lutein is an oxycarotenoid primarily found in dark-green leafy vegetables such as spinach and kale. Other dietary sources which contain moderate amounts of lutein include corn, egg yolks, and fruits like oranges and kiwi. Although a number of in vivo studies have demonstrated the anti-inflammatory effect of lutein, its in vitro anti-inflammatory molecular mechanism of action is unknown. In this study, we have investigated the in vitro anti-inflammatory effect of lutein using LPS-stimulated mouse macrophage cell line (RAW 264.7). The inhibition of LPS-stimulated nitric oxide (NO) was measured and the expression of inducible NO synthase (iNOS) was assessed at the mRNA and protein levels in mouse macrophage cells after treatment with lutein. Lutein decreased the LPS-induced NO production by 50% compared to LPS alone. Real-time PCR analysis showed a 1.9-fold reduction in iNOS expression at the mRNA level. Western blotting revealed that lutein decreased LPS-induced iNOS expression at the protein level by 72.5%. The results of this study suggest the anti-inflammatory properties of lutein demonstrated by the decrease in the expression of iNOS at the mRNA and protein levels in RAW 264.7 mouse macrophage cells.  相似文献   
5.
Intestinal carotenoid absorption is greatly affected by dietary factors. In this study, it was hypothesized that lipids with varying functional groups may influence differentially lutein bioavailability. Hence, the influence of glyco‐, phospho‐, neutral, crude (mixture of lipids) lipids, or mixed micelles (control) on the percent lutein micellarization in vitro and its postprandial plasma, liver, and eye response in mice were investigated. Results show that the percent micellarization of lutein with crude lipids and glycolipids were higher (91.4 and 45.7%) than control, while no significant difference was found between phospho‐ and neutral lipids. The mean plasma response of lutein was higher for crude‐ (6 times), glyco‐ (3 times), phospho‐ (2.7 times), and neutral (2 times) lipid than control (12.4 ± 1.18 nmol/mL 8 h?1) group. Lutein levels (pmol/g) in liver were higher in crude (7.4 ± 1) and phospho‐ (3.6 ± 0.8) lipid groups while in eyes it was higher in glyco‐ (54.0) and neutral (21.2) lipid groups than control. The influential effect of glyco‐ and phospholipids may be due to smaller micellar size (glyco‐upto 3.43 µm, phospho‐ upto 5.78 µm) than the neutral lipids (upto 66 µm). Ingestion of lutein with glycolipid or phospholipids may improve lutein bioavailability. Practical applications: The findings of the present study will be useful in nutritional and biomedical applications for feeding lutein with specific lipid combinations to achieve enhanced lutein absorption. Specifically, feeding diet/emulsion with lutein and glyco‐ and phospholipid combination may reduce the risk of macular degeneration, owing to the influential effect of these lipids on intestinal absorption of lutein.  相似文献   
6.
The distribution of protein, ash, lutein, tocopherols and tocotrienols in the germ, bran and endosperm portions was studied in seeds of two einkorn accessions and one bread wheat. The two einkorns showed a higher content of most compounds, but the distribution within the kernel was similar in both species. The germ fraction showed the highest concentration of protein, lutein, α-tocopherol, β-tocopherol and total tocols. Ash, α-tocotrienol and β-tocotrienol levels were highest in the bran fraction, although significant quantities were detected also in the germ and, for tocotrienols, in the flour.  相似文献   
7.
Epidemiological and experimental studies provide supportive evidence that lutein, a major carotenoid, may act as a chemopreventive agent against atherosclerosis, although the underlying molecular mechanisms are not well understood. The main aim of this study was to investigate the effects of lutein on the alleviation of atherosclerosis and its molecular mechanisms involved in oxidative stress and lipid metabolism. Male apolipoprotein E knockout mice (n = 55) were fed either a normal chow diet or a high fat diet (HFD) supplemented with or without lutein for 24 weeks. The results showed that a HFD induced atherosclerosis formation, lipid metabolism disorders and oxidative stress, but noticeable improvements were observed in the lutein treated group. Additionally, lutein supplementation reversed the decreased protein expression of aortic heme oxygenase‐1 and increased the mRNA and protein expressions of aortic nicotinamide‐adenine dinucleotide phosphate oxidase stimulated by a HFD. Furthermore, the decreased mRNA and protein expression levels of hepatic peroxisome proliferator‐activated receptor‐α, carnitine palmitoyltransferase 1A, acyl CoA oxidase 1, low density lipoprotein receptors and scavenger receptor class B type I observed in mice with atherosclerosis were markedly enhanced after treatment with lutein. Taken together, these data add new evidence supporting the anti‐atherogenic properties of lutein and describing its mechanisms of action in atherosclerosis prevention, including oxidative stress and lipid metabolism improvements.  相似文献   
8.
红蜜南瓜中叶黄素的超临界CO2流体萃取分离方法研究   总被引:2,自引:0,他引:2  
研究了日本红蜜南瓜中叶黄素的超临界CO2萃取方法,确定了提取叶黄素的最佳工艺条件,即萃取压力15MPa、萃取温度40℃、CO2流量20kg/h、萃取时间4h.在上述条件下,叶黄素的提取率可达到88%,提取物中的叶黄素含量达到88.2%.  相似文献   
9.
ABSTRACT

Mathematical models of pizza baking by forced and natural convection heating methods were developed describing heat and mass transfer phenomena. The models were solved using finite difference technique and a simulation language. Moisture and temperature histories were collected at different baking conditions. The models and experimental data were used to determine mass transfer properties—moisture diffusivities of crust, tomato paste and cheese, and moisture transfer coefficient. Heat transfer coefficient was measured by minimizing the internal heat resistance.  相似文献   
10.
This work aims to study supercritical anti-solvent micronization of marigold derived purified lutein that was dissolved in the mixture of hexane and ethyl acetate (70:30 v/v), the solvent used as the mobile phase for chromatographic purification. The results show significant effect of pressure on the morphology of micronized lutein particles. The increase in lutein initial concentration from 1.5 mg/ml to 3.2 mg/ml and the increase in SC-CO2 flow rate from 15 ml/min to 25 ml/min show no significant effects on the morphology of lutein particles. However, the reduction of mean particle size from about 2 μm to 0.8 μm was observed by increasing SC-CO2 flow rate. The X-ray diffraction patterns of the micronized lutein particles show apparent amorphous nature, while the Fourier transform infrared spectroscopy results show that no chemical structural changes occurred. Moreover, the solubility of the micronized lutein particles in aqueous solution was found to increase significantly from being almost insoluble to having approximately 20% solubility  相似文献   
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