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71.
72.
Anti‐adhesion activity of thyme (Thymus vulgaris L.) extract,thyme post‐distillation waste,and olive (Olea europea L.) leaf extract against Campylobacter jejuni on polystyrene and intestine epithelial cells
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73.
Tovilovic G Zogovic N Harhaji-Trajkovic L Misirkic-Marjanovic M Janjetovic K Vucicevic L Kostic-Rajacic S Schrattenholz A Isakovic A Soskic V Trajkovic V 《ChemMedChem》2012,7(3):495-508
The protective ability of novel arylpiperazine-based dopaminergic ligands against nitric oxide (NO)-mediated neurotoxicity is investigated. The most potent neuroprotective arylpiperazine identified during the study was N-{4-[2-(4-phenyl-piperazin-1-yl)ethyl]-phenyl}picolinamide, which protected SH-SY5Y human neuron-like cells from the proapoptotic effect of NO donor sodium nitroprusside (SNP) by decreasing oxidative stress, mitochondrial membrane depolarization, caspase activation and subsequent phosphatydilserine externalization/DNA fragmentation. The protective effect was associated with the inhibition of proapoptotic (JNK, ERK, AMPK) and activation of antiapoptotic (Akt) signaling pathways, in the absence of interference with intracellular NO accumulation. The neuroprotective action of arylpiperazines was shown to be independent of dopamine receptor binding, as it was not affected by the high-affinity D?/D? receptor blocker butaclamol. These results reported support the further study of arylpiperazines as potential neuroprotective agents. 相似文献
74.
V Bučević-Popović M Sprung B Soldo M Pavela-Vrančič 《Chembiochem : a European journal of chemical biology》2012,13(13):1913-1920
The adenylation (A) domain in nonribosomal peptide synthetases catalyses a two-step reaction in which an amino acid is activated and then transferred to the neighbouring thiolation (T) domain. In this study, we investigated the role of the conserved A9 core sequence of the A-domain of tyrocidine synthetase 1, by analysis of single amino acid mutations in the A9 region. Mutation of an absolutely conserved proline (P490G) significantly reduced the conformational stability of the protein, as evidenced by increased susceptibility to proteolytic cleavage and denaturation. All mutant A-domains were capable of amino acid activation, but the activity in the overall reaction was reduced. Surprisingly, the S491R mutant (mutation at the first residue following the A9 motif) showed elevated overall activity compared to the wild-type protein. Our results suggest that the A9 core sequence plays a role in the second reaction step, in which it could serve as a "clip" for the proper positioning of residues important for the interaction with the T-domain, and/or stabilisation of the thioester-forming conformation. 相似文献
75.
Fluoride in teas of different types and forms and the exposure of humans to fluoride with tea and diet 总被引:1,自引:0,他引:1
Human exposure to the fluoride (F) from commercial teas was assessed. The efficacy of the F leaching was determined from the total F (Ft) contents in the teas (53–435 mg/kg) and the F concentrations in tea infusions (0.31–3.55 mg/l of free F available to human organism). Both were determined with a fluoride ion selective electrode. The efficacies of F leaching from the green, oolong and black teas were 55–90% with continuous, and 74–100% by repeated infusions, and were not affected by the type or the manufactured form. Lower efficacies were observed from Pu’erh teas, 21–38% with continuous, and 37–59% by repeated infusions. The daily intake of F with daily consumption of five cups of tea can represent 9–101% of the adequate intake (AI) for an adult person with 70 kg, and with tea and diet 25–173% of the AI in non-fluoridated and 35–210% of AI in fluoridated areas. The upper limits of these intakes can be already associated with a risk of developing F-related adverse effects. 相似文献
76.
Temerinac-Ott M Ronneberger O Ochs P Driever W Brox T Burkhardt H 《IEEE transactions on image processing》2012,21(4):1863-1873
We propose an algorithm for 3-D multiview deblurring using spatially variant point spread functions (PSFs). The algorithm is applied to multiview reconstruction of volumetric microscopy images. It includes registration and estimation of the PSFs using irregularly placed point markers (beads). We formulate multiview deblurring as an energy minimization problem subject to L1-regularization. Optimization is based on the regularized Lucy-Richardson algorithm, which we extend to deal with our more general model. The model parameters are chosen in a profound way by optimizing them on a realistic training set. We quantitatively and qualitatively compare with existing methods and show that our method provides better signal-to-noise ratio and increases the resolution of the reconstructed images. 相似文献
77.
Biological and nutritional properties of blackcurrant berries (Ribes nigrum L.) under conditions of shading nets
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78.
Tomislav Mašek Luka Krstulović Diana Brozić Marina Vranić Maja Maurić Miroslav Bajić Kristina Starčević 《European Food Research and Technology》2014,238(4):635-640
The objective of the study was to explore whether it is possible to alter cow colostrum and early milk fatty acid composition with a low level of fat supplement, high in docosahexaenoic (DHA) and eicosapentaenoic (EPA) fatty acid. Diets included a control diet and a diet supplemented with DHA- and EPA-enriched fat supplement. Addition of fat supplement significantly decreased saturated fatty acids, C14:0 and C16:0 and increased the values of monounsaturated fatty acids, polyunsaturated fatty acids (PUFA), n3 fatty acids, EPA, DHA, C18:1n9cis and C18:1n11trans. The percentage of short-chain fatty acids significantly increased with the progress of lactation, while the percentage of PUFA, n3 and n6 significantly decreased. These results showed that fat supplement, high in DHA and EPA, modified the fatty acid profile of colostrum and milk fat and increased the proportion of beneficial fatty acids for human health. 相似文献
79.
Vesna Ilić Zoran Šaponjić Vesna Vodnik Ricardo Molina Suzana Dimitrijević Petar Jovančić Jovan Nedeljković Maja Radetić 《Journal of Materials Science》2009,44(15):3983-3990
This study discusses the possibility of using the corona (electric discharge at atmospheric pressure) treatment for fiber
surface activation that can facilitate the loading of Ag nanoparticles (NPs) from colloids onto the polyester and polyamide
fabrics and thus enhance their antifungal activity against Candida albicans. The laundering durability of achieved effects and the influence of dyeing of fabrics with disperse dyes on their antifungal
efficiency were studied. The morphology of fibers loaded with Ag nanoparticles was characterized by SEM whereas X-ray photoelectron
spectroscopy was used for the evaluation of surface chemical changes. Corona pretreated polyester and polyamide fabrics loaded
with Ag nanoparticles showed better antifungal properties compared to untreated fabrics. The advantage of corona treated fabrics
became even more prominent after washing test, particularly for polyester fabrics. Antifungal efficiency of polyester and
polyamide fabrics loaded with Ag nanoparticles were almost unaffected by dyeing process. 相似文献
80.
Bituh T Marovic G Franic Z Sencar J Bronzovic M 《Journal of hazardous materials》2009,162(2-3):1199-1203
The contents of natural radionuclides (radium, uranium and potassium) were measured in the area of a phosphate fertilizer factory in central Croatia, as a part of extended and still ongoing monitoring program of radioactive contamination of human environment in Croatia that is performed by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health in Zagreb. Activity concentrations in all analysed media (waste water, trickling water from piezometers, phosphogypsum deposit and final products) considerably fluctuated, especially in phosphogypsum and waste water. Mean (226)Ra activity concentration in waste phosphogypsum was measured to be 483+/-190 Bqkg(-1). Based on that value, it was estimated that 4 million m(3) of phosphogypsum that have been deposited up to now contain about 4.3 x 10(12) Bq, i.e. about 200 g of (226)Ra. However, effective dose for an adult that would be incurred by consumption of water from nearby wells was estimated to be 5.3+/-1.3 microSv. The results show that (226)Ra activities cause effective doses, which are below the recommended maximum as the estimated annual (226)Ra effective dose does not exceed 0.1 mSv as recommended by the World Health Organization. 相似文献