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21.
The gross composition and amino acid content of the proteins of barley, corn, rye and wheat grains were determined. Leaf protein concentrates (LPC) were produced from the green matter of clover, lucerne, barley and ryegrass using standard methods and analysed as for the cereal grains. Each cereal was mixed with each concentrate at a protein ratio of 2:1, respectively. The chemical score (CS) and essential amino acid index (EAAI) of the cereals, the protein concentrates and their mixtures were calculated. The biological value (BV) and true digestibility (TD) of all proteins were determined on rats using the Thomas-Mitchell balance method. LPC proteins contained more lysine (4.6–6.0%) but less cystine than cereal proteins (2.8–3.8 and 2.3–2.7 g per 16 g N, respectively). The CS and BV of LPC proteins were low (30–40 and 44–58, respectively) because of the low cystine content. Mixing cereals with LPC improved the CS, EAAI and BV of their proteins. The BV of the protein mixtures was in almost every case higher than that of either protein alone, but the digestibility of the cereal proteins was reduced as a result of admixture with LPC, especially with clover LPC.  相似文献   
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Europium doped hafnium dioxide nanoparticles were crystallized using biologically friendly microwave hydrothermal method and employed in observation of small rodents tissues.Main solvent in synthesis is water,in consequence nanoparticles are found surrounded by thin hydroxide layer.Size of the nanoparticles is controlled by temperature of calcination.1200℃heating causes drop of luminescence intensity,explained as damage of high symmetry surface emission centers in the nanocrystals.On the other hand,growth of crystallites increases intensity of X-ray and electron beam excited luminescence.This makes them promising activator in photodynamic therapy.  相似文献   
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The aim of this study was to evaluate the cytotoxicity of dried aqueous extracts from Thymus serpyllum (ExTs), Thymus vulgaris (ExTv), Majorana hortensis (ExMh), and Mentha piperita (ExMp), and the phenolic compounds caffeic acid (CA), rosmarinic acid (RA), lithospermic acid (LA), luteolin-7-O-glucuronide (Lgr), luteolin-7-O-rutinoside (Lr), eriodictiol-7-O-rutinoside (Er), and arbutin (Ab), on two human breast cancer cell lines: Adriamycin-resistant MCF-7/Adr and wild-type MCF-7/wt. In the MTT assay, ExMh showed the highest cytotoxicity, especially against MCF-7/Adr, whereas ExMp was the least toxic; particularly against MCF-7/wt cells. RA and LA exhibited the strongest cytotoxicity against both MCF-7 cell lines, over 2-fold greater than CA and Lgr, around 3-fold greater than Er, and around 4- to 7-fold in comparison with Lr and Ab. Except for Lr and Ab, all other phytochemicals were more toxic against MCF-7/wt, and all extracts exhibited higher toxicity against MCF-7/Adr. It might be concluded that the tested phenolics exhibited more beneficial properties when they were applied in the form of extracts comprising their mixtures.  相似文献   
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Edible macromycetes for ages have been used by humans, not only as a source of food, but medicinal resources as well; however, this happened first of all in the civilizations of the East. In recent years, they have become subjects of numerous scientific studies in Europe and United States. It was shown that they constitute a rich source of bioactive compounds exhibiting antitumor, hypocholesterolemic, immunosuppressive, antioxidant, antimicrobial and anti-inflammatory properties. These compounds include non-starch polysaccharides, polysaccharide–protein and polysaccharide–peptide complexes, ribonucleases, proteases and lectins. Mushrooms also accumulate many secondary metabolites, that is, polyphenols, polyketides, terpenes and steroids. Most of the above-mentioned compounds exhibit a clinical potential. In this article, the health-promoting potential of mushroom polisaccharides was characterized. The special attention was paid on their antitumor, antiatherogenic and prebiotic activities.  相似文献   
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An automatic flow procedure based on a multicommuted flow analysis (MCFA) for the determination of the total polyphenolic content in food samples employing chemiluminescence (CL) as a detection technique is described. The concept of applying three-way solenoid valves in flow injection analysis was chosen in order to develop an environmentally friendly system which enables minimal consumption of reagents and waste generation. The method was based on the enhancing effect of polyphenolic antioxidants on CL of Mn(IV)–formaldehyde–hexametaphosphate system. The calibration graph obtained for standard solutions of gallic acid was linear in the range 5–150 μg L?1 with a detection limit of 1.5 μg L?1. The relative standard deviation for 20 measurements was between 1.1 and 2.4 %. The sampling rate was 60 determinations per hour. The proposed method was found to be selective to polyphenol detection and was successfully applied to the determination of the total polyphenol index in 27 diverse plant-derived food samples (wine, tea, coffee, fruit and vegetable juices, herbs, spices and extracts of olive oil). A significant correlation between the total phenolic contentment determined by the MCFA-CL method and the total reducing capacity determined by Folin–Ciocalteu method and total antioxidant activity estimated by the DPPH method was observed.  相似文献   
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In this article, we propose a novel super‐agent‐based framework for reputation management and community formation in decentralized systems. We describe this framework in the context of Web service selection where agents with more capabilities act as super‐agents. These super‐agents serve as reputation managers to maintain reputation information of services and share the information with other consumer agents that have fewer capabilities than the super‐agents. In addition, super‐agents can maintain communities and build community‐based reputation for a service based on the opinions from all community members that have similar interests and judgement criteria as the super‐agents or the other community members. A practical reward mechanism is also introduced to create incentives for super‐agents to contribute their resources (to maintain reputation and form communities) and provide truthful reputation information. Experimental results obtained through simulation confirm that our approach achieves better effectiveness and scalability compared to the systems that do not use super‐agents and that do not form communities.  相似文献   
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Two generations of positively charged poly(amidoamine) dendrimers (PAMAMs) were selected for study as potential carriers for the anticancer drug 5-fluorouracil (5FU), a drug primarily used in the treatment of colorectal cancer. Analytical techniques, such as UV-Vis spectrophotometry, NMR Spectroscopy and Laser Doppler Velocimetry (LDV), have shown that the most critical factor determining the formation of a PAMAM–5FU complex is the starting components’ protonation degree. The tests confirmed the system’s ability to attach about 20 5FU molecules per one dendrimer molecule for the G4PAMAM dendrimer and about 25 molecules for the G6PAMAM dendrimer, which gives a system yield of 16% for the fourth generation and 5% for sixth generation dendrimers. Additionally, using the QCM-D method, the adsorption efficiency and the number of drug molecules immobilized in the dendrimer structure were determined. A new aspect in our study was the determination of the change in zeta potential (ζ) induced by the immobilization of 5FU molecules on the dendrimer’s outer shell and the importance of this effect in the direct contact of the carrier with cells. Cytotoxicity tests (resazurin reduction and MTS tests) showed no toxicity of dendrimers against mouse fibroblast cells (L929) and a significant decrease in cell viability in the case of four human malignant cell lines: malignant melanoma (A375), glioblastoma (SNB-19), prostate cancer (Du-145) and colon adenocarcinoma (HT-29) during incubation with PAMAM–5FU complexes. The purpose of our work was to investigate the correlation between the physicochemical properties of the carrier and active substance and the system efficiency and optimizing conditions for the formation of an efficient system based on PAMAM dendrimers as nanocarriers for 5-fluorouracil. An additional aspect was to identify potential application properties of the complexes, as demonstrated by cytotoxicity tests.  相似文献   
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