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361.
362.
Riss J Décordé K Sutra T Delage M Baccou JC Jouy N Brune JP Oréal H Cristol JP Rouanet JM 《Journal of agricultural and food chemistry》2007,55(19):7962-7967
The effects of spirulina and its chromophore phycocyanin, both without bound Se or selenium-enriched, were studied on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anions, and NAD(P)H oxidase expression in hamsters. Forty hamsters were divided into 5 groups of 8 and fed an atherogenic diet for 12 weeks. They received by gavage either 7.14 mL/(kg day) phycocyanin (PC), Se-rich phycocyanin (SePC), spirulina (SP) or Se-rich spirulina (SeSP) in water, or water as control. SeSP and SePC supplied 0.4 microg of Se per 100 g body weight. Plasma cholesterol and non-HDL cholesterol concentrations were lower in group consuming SePC. HDL-cholesterol was never affected. SePC significantly increased plasma antioxidant capacity by 42% compared with controls. A sparing effect in liver glutathione peroxidase (87% on average) and superoxide dismutase (56% on average) activity was observed for all the groups compared to controls. Aortic fatty streak area was significantly reduced in the experimental groups, especially by PC (82%) and SePC (85%). Cardiac production of superoxide anion significantly decreased by approximately 46-76% in the four experimental groups and especially in SePC group (76%). The expression of p22phox subunit of NAD(P)H oxidase decreased by 34% after consumption of SePC. The results indicate that chronic consumption of Se-rich spirulina phycocyanin powerfully prevents the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and at a lesser extent improving the serum lipid profile. 相似文献
363.
In this study, the efficacy of successive intranasal (i.n.)/intramuscular (i.m.) vaccination against Aujeszky's disease virus (ADV) was assessed in experimental pigs. The double deletion-mutant Kaplan gE-gl- was used for i.n. vaccination at 4 weeks of age and the commercially available Bartha strain, suspended in an oil-in-water emulsion, was used for the i.m. booster vaccination at 10 weeks of age. Efficacy was compared with that of the traditional double i.m. vaccination with the commercially available Bartha strain at 10 and 14 weeks of age by challenging the pigs at the end of the fattening period. There were significant differences in clinical signs, mean daily weight gain, and virus excretion between the vaccinated groups and the unvaccinated controls; however, the differences between the vaccinated groups were not statistically significant. 相似文献
364.
D Maes H Deluyker M Verdonck F Castryck C Miry B Vrijens A de Kruif 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(5):341-352
Epidemiological aspects of Mycoplasma hyopneumoniae (Mh), influenza H1N1 and H3N2 viruses, and Aujeszky's disease virus (ADV) were investigated in slaughter pigs from 50 fattening pig herds. Herd factors as potential risk indicators for respiratory disease were obtained by means of a questionnaire. At slaughter, blood samples were collected from each herd, and the proportion of seropositive pigs per herd was assessed for each of these pathogens. The median herd-level seroprevalence of the agents were: Mh 88%, H1N1 100%, H3N2 60% and ADV 90%. The percentage of herds in which all investigated fattening pigs were seronegative for these agents was: Mh 0%, H1N1 0%, H3N2 12% and ADV 18%. The percentage of herds in which all investigated fattening pigs were seropositive for these agents was: Mh 8%, H1N1 71%, H3N2 22% and ADV 40%. A positive association was found between influenza H1N1 and H3N2 viruses, and a negative association between influenza H3N2 virus and ADV. There were no risk indicators for the seroprevalence of Mh. Three risk indicators were associated with the seroprevalence of influenza H1N1 virus: a fully slatted floor, an increasing number of pigs in the municipality and dry feeding. Three risk indicators were found for the seroprevalence of influenza H3N2 virus: purchase of pigs from > or = two herds, an increasing number of pigs in the municipality and natural ventilation. The seroprevalence of ADV was influenced by two risk indicators: an increasing number of pig herds in the municipality and an increasing number of pigs per pen. 相似文献
365.
Fixation of radiocaesium traces in a weathering sequence mica → vermiculite → hydroxy interlayered vermiculite 总被引:1,自引:1,他引:0
Radiocaesium fixation in soils is reported to occur on frayed edge sites of micaceous minerals. The weathering of mica in acid soils may therefore influence the Cs+ fixation process and thereby the mobility of the radiopollutant. We produced a laboratory weathering model biotite → trioctahedral vermiculite → oxidized vermiculite → hydroxy interlayered vermiculite (HIV) and quantified the Cs+ fixation of each mineral both in a fixed K+ –Ca2+ background and in acid conditions. The transformation process was achieved through K depletion by Na-tetraphenylboron, oxidation with Br2 and Al-intercalation using NaOH and AlCl3 . In a constant K+ –Ca2+ background, vermiculite fixed 92–95% of the initial 137 Cs+ contamination while biotite and HIV fixed only 18–33%. In acid conditions, the interlayer occupancy by either potassium (biotite) or hydroxy-Al groups (HIV) strongly limited Cs+ fixation to 1–4% of the initial 137 Cs+ contamination. Cs+ fixation occurred on vermiculitic sites associated with micaceous wedge zones. Though both oxidized and trioctahedral vermiculites fixed similar Cs+ amounts in a constant K+ –Ca2+ background (92–95%), the oxidized vermiculite retained much more radiocaesium in acid conditions (78–84% against 54–59%), because of its dioctahedral character. 相似文献
366.
The physicochemical properties of small‐ and large‐granule wheat starches were investigated to reveal whether gelatinization properties and rheological behavior differ between size classes of wheat starch. All samples contained 60% water (w/w, wb). The starch granule size and shape were examined by scanning electron microscopy in the separated A‐ and B‐type granule populations and in the whole wheat starch granule population. Differential scanning calorimetry (DSC) and electron spin resonance (ESR) analyses were performed in parallel with rheological measurements using dynamic mechanical thermal analysis (DMTA) to relate the viscoelastic changes to modifications in dynamic properties of aqueous solutions and structural disorganization of starch. The small (B‐type) granules had slightly higher gelatinization temperature and lower gelatinization enthalpy than did the large (A‐type) granules. Also, B‐type granules had higher enthalpy for the amylose‐lipid complex transition. Moreover, our results suggested that small granules have higher affinity for water at room temperature. It seems that there is a less ordered arrangement of the polysaccharide chains in the smaller granules when compared with the larger ones. These differences in functional properties of small and large granules suggested that the granule size distribution is an important parameter in the baking process. 相似文献