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1.
In this study we investigated whether alpha-tocopherol can be spared by ubiquinol-3 during autoxidation of multilamellar liposome. A lipophilic azocompound, 2,2'-azobis-(2,4-dimethyl-valeronitrile), was chosen to initiate liposome autoxidation. The effect of either alpha-tocopherol, ubiquinol-3, or a mixture of them was compared. Rates of conjugated diene formation and concomitant disappearance of the two antioxidants was measured. Since the inhibition rate constant for the scavenging of peroxyl radical for alpha-tocopherol was higher than that for quinol-3, it was concluded that alpha-tocopherol is regenerated by ubiquinol-3. 相似文献
2.
Biagina Chiofalo Vittorio Lo Presti Vincenzo Chiofalo Fabio Gresta 《Animal Feed Science and Technology》2012,171(2-4):230-239
The aim of this study was to investigate the productive traits and fatty acid profiles of eight sweet varieties of Lupinus albus, Lupinus angustifolius and Lupinus luteus cultivated in a Mediterranean environment (Sicily, southern Italy). This is being done to identify the most suitable species, from an agronomical and nutritional point of view, for supporting animal husbandry in this area. Seed yield, oil quantity and oil quality were considerably different depending on the genotype. L. albus showed the highest yield (2.0–2.4 t/ha), 100 seed weight (27.0 g, on average), oil content (70.4–75.5 g/kg), and n?3/n?6 polyunsaturated fatty acid ratio (0.39–0.51), L. angustifolius showed the highest content of saturated fatty acids (21.03–26.66 g/100 g) and L. luteus showed the highest levels of n?6 polyunsaturated fatty acids (47.56–50.85 g/100 g), unsaturated/saturated (4.93–5.62) and polyunsaturated/saturated (3.33–3.99) fatty acid ratios and the best atherogenic (0.06) and thrombogenic (0.09–0.11) indices. The data obtained suggests L. albus as the most interesting lupin species for aiding the crop-livestock food chain and L. luteus as a promising crop due to its high nutritive traits for the Mediterranean environment. 相似文献
3.
Felice Esposito Filippo Flavio Angileri Peter Kruse Luigi Maria Cavallo Domenico Solari Vincenzo Esposito Francesco Tomasello Paolo Cappabianca 《PloS one》2016,11(4)
BackgroundFibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks.MethodsA comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors.ResultsA total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a significant advantage to fibrin sealant use. Two small case series studies evaluated the effect of fibrin sealants in persistent cerebrospinal fluid leak treatment, but did not establish firm efficacy conclusions. Specific adverse reports where fibrin sealants were used for dura sealing were limited, with only 8 cases reported in neurosurgical procedures since 1987 and most reporting only a speculative relationship/association with fibrin sealant exposure.ConclusionsA major finding of this systematic literature review is that there is a paucity of randomized studies that have evaluated the effectiveness and safety of fibrin sealants in providing intraoperative watertight dura closure and post-operative cerebrospinal fluid leakage. Among the limited studies available, evidence from a single randomized, controlled trial indicates that fibrin sealants provide a higher rate of intraoperative watertight closure of the dura suture line than control, albeit with a higher rate of postoperative cerebrospinal fluid leakage. Evidence from non-randomized, controlled trials suggests that fibrin sealants may be effective in preventing cerebrospinal fluid leaks with an acceptable safety profile. There is a substantial need for randomized, controlled clinical trials or well-designed prospective observational trials where the conduct of a randomized trial is not feasible to fully assess the impact of fibrin sealant utilization on the rates of intraoperative dura closure, postoperative cerebrospinal leakage, and safety. 相似文献
4.
This study aimed to test the concurrent validity of an electronic version (to run on tablet) of a sleep diary derived from the core Consensus Sleep Diary compared with the traditional paper and pencil version. To this end, 15 healthy volunteers (6 males; mean age 37.20 ± 17.55 years) every morning, for at least 7 consecutive days, filled both paper and electronic sleep diary. Furthermore, sleep was objectively assessed through actigraphy. With reference to all sleep parameters examined, no significant differences were observed between paper and electronic sleep diary. As expected, paper and electronic sleep diary showed the same poor agreement with actigraphic estimates of sleep quantity and sleep quality. On the basis of the present data, we can conclude that electronic sleep diary performs like paper sleep diary. Bearing in mind that electronic sleep diary presents several benefits in comparison to the paper sleep diary (e.g. avoiding of the “parking lot syndrome”, in which patient retrospectively completes more days at the same time; reducing the time for data entry and scoring), we suggest that, if the present findings will be confirmed also in clinical populations, electronic sleep diary should replace paper sleep diary in both research and clinical settings. 相似文献
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6.
Vincenzo Pavone Angelina Lombardi Michele Saviano Benedetto Di Blasio Flavia Nastri Roberto Fattorusso Ornella Maglio Carla Isernia 《Biopolymers》1994,34(11):1505-1515
In the present paper we describe the synthesis, purification, single crystal x-ray analysis, and solution structural characterization by nmr spectroscopy, combined with restrained molecular dynamic simulations, of the cyclic hexapeptide cyclo-(Pro-Phe-β-Ala-Phe-Phe-β-Ala). The peptide was synthesized by classical solution methods and the cyclization of the free hexapeptide was accomplished in good yields in diluted methylenechloride solution using N, N-dicyclohexyl-carbodiimide. The compound crystallizes in the monoclinic space group P21 from methanol/ethyl acetate. The molecule adopts in the solid state a conformation characterized by cis β-Ala6-Pro1 peptide bond. The α-amino acid residues are at the corner positions of turned structures. The Pro1-Phe2 segment is incorporated in a pseudo type I β-turn, while Phe4-Phe5 is in a typical type I β-turn. Assignment of all 1H and 13C resonances was achieved by homo- and heteronuclear two-dimensional techniques in dimethylsulfoxide (DMSO) solutions. The conformational analysis was based on inter-proton distances derived from rotating frame nuclear Overhauser effect spectroscopy spectra and homonuclear coupling constants. Restrained molecular dynamic simulation in vacuo was also performed to built refined molecular models. The molecule is present in DMSO solution as two slowly interconverting conformers, characterized by a cis-tran isomerism around the β-Ala6-Pro1 peptide bond. This work confirms our expectations on the low propensity of β-alanyl residues to be positioned at the corners of turned structure. © 1994 John Wiley & Sons, Inc. 相似文献
7.
The experience of the Toronto General Hospital in the use of nonspecific stimulation of the immune system with bacille Calmette-Guérin (BCG) for the treatment of cancer of the gastrointestinal tract, malignant melanoma and breast cancer is described. The results are presented in terms of survival curves. The use of BCG administered intraperitoneally in a randomized study of patients with gastric, pancreatic and colorectal cancer proved of no benefit. On the other hand, when BCG was given orally in a randomized study of patients with resectable cancer of the colon and in nonrandomized consecutive studies of patients with malignant melanoma and stage IV carcinoma of the breast survival was increased. In a group of patients with advanced gastrointestinal cancer selective stimulation of the immune system with NED 137 produced a significant increase in survival when compared with the survival of historical controls (the patients given BCG intraperitoneally along with 5-fluorouracil for gastrointestinal cancer). The results of these studies suggest the need for a more rational approach in manipulating the immune response that would combine chemotherapy with selective stimulation of the immune system. 相似文献
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