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1.
Pilot study of the effect of acemannan in cats infected with feline immunodeficiency virus. 总被引:7,自引:0,他引:7
K M Yates L J Rosenberg C K Harris D C Bronstad G K King G A Biehle B Walker C R Ford J E Hall I R Tizard 《Veterinary immunology and immunopathology》1992,35(1-2):177-189
Acemannan, a complex carbohydrate shown to stimulate interleukin-1, tumor necrosis factor alpha and prostaglandin E2 production by macrophages, has also demonstrated antiviral activity in vitro against human immunodeficiency virus, Newcastle disease virus and influenza virus. A pilot study was undertaken to determine acemannan's effect in 49 feline immunodeficiency virus (FIV) infected cats with clinical signs of disease (Stage 3, 4 or 5), 23 of which had severe lymphopenia. Cats received acemannan either by intravenous (Group 1) or subcutaneous (Group 2) injection once weekly for 12 weeks, or by daily oral (Group 3) administration for 12 weeks. Upon entry into the study, cats were randomly assigned to one of the three groups. Laboratory analyses were performed at the beginning of the study and at Weeks 6 and 12. Cats were allowed to continue with a predetermined maintenance regimen of acemannan after completing the 12-week study. Thirteen cats died during the course of treatment. Upon necropsy, the most frequent histopathologic findings were neoplastic, kidney and pancreatic disease. Friedman's two-way ANOVA test showed no significant differences in efficacy among groups administered acemannan by the different routes. Therefore, groups were combined and a signed-ranks test was used to determine changes over time. A significant increase was seen in lymphocyte counts (P < 0.001). Neutrophil counts decreased significantly (P = 0.007), as did incidence of sepsis (P = 0.008). When cats entering with lymphopenia were analyzed separately, a much greater increase in lymphocyte counts was noted (235%) compared with non-lymphopenic cats (42%). A survival rate of 75% was found for all three groups. Thirty-six of 49 animals are alive 5-19 months post-entry. These results suggest that acemannan therapy may be of significant benefit in FIV-infected cats exhibiting clinical signs of disease. 相似文献
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Adding supplements to hen feed can increase egg nutritional value. Astaxanthin, tocotrienols, and tocopherols are potent antioxidants that provide health benefits to humans. We hypothesized that the addition of these nutrients to hen feed would result in an increased nutrient content in egg yolk with minimum changes in functional properties. Laying hens (Hy-Line W-36 breed) were fed four diets with different supplementation levels of palm toco concentrate and algae biomass containing astaxanthin for 8 weeks. Egg yolks were analyzed for physical, chemical, and functional properties. The feed with the highest nutrient concentration was also studied for stability of these antioxidants using the Arrhenius approach. No significant differences were observed in functional properties except for emulsification capacity and sensory characteristics among eggs from different diet treatments. Changes in egg yolk color reached the maximum values at day 8. Incorporation of tocopherols and tocotrienols increased until day 8, astaxanthin incorporation increased until day 10, and all decreased thereafter. Feed nutrients resulted in a dose-response relationship of these compounds in the egg yolk. The transfer efficiency ranged from 0 to 9.9% for tocotrienols and tocopherols and from 7.6 to 14.9% for astaxanthin at their peak values. Results of the Arrhenius accelerated stability study showed significant differences in the shelf life of various nutrients, and these results can be used to properly formulate and store the feed materials. 相似文献
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Nimesha Fernando Joe Panozzo Michael Tausz Robert M. Norton Glenn J. Fitzgerald Samuel Myers Cassandra Walker James Stangoulis Saman Seneweera 《Journal of Cereal Science》2012
We investigated wheat (Triticum aestivum) grain quality under Free Air CO2 Enrichment (FACE) of 550 ± 10% CO2 μmol mol−1. In each of two full growing seasons (2008 and 2009), two times of sowing were compared, with late sowing designed to mimic high temperature during grain filling. Grain samples were subjected to a range of physical, nutritional and rheological quality assessments. Elevated CO2 increased thousand grain weight (8%) and grain diameter (5%). Flour protein concentration was reduced by 11% at e[CO2], with the highest reduction being observed at the late time of sowing in 2009, (15%). Most of the grain mineral concentrations decreased under e[CO2] - Ca (11%), Mg (7%), P (11%) and S (7%), Fe (10%), Zn (17%), Na (19%), while total uptake of these nutrients per unit ground area increased. Rheological properties of the flour were altered by e[CO2] and bread volume reduced by 7%. Phytate concentration in grains tended to decrease (17%) at e[CO2] while grain fructan concentration remained unchanged. The data suggest that rising atmospheric [CO2] will reduce the nutritional and rheological quality of wheat grain, but at high temperature, e[CO2] effects may be moderated. Reduced phytate concentrations at e[CO2] may improve bioavailability of Fe and Zn in wheat grain. 相似文献
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Walker R Seifriz W Ketcham HH Mateer F Calkins FC Wells FL Appleby A 《Science (New York, N.Y.)》1952,116(3018):486-488
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Rates of carbon dioxide evolution and degradation rates of metamitron, metazachlor and metribuzin were measured in two soils in the presence of three microbial inhibitors. The nonselective microbial inhibitor sodium azide reduced both carbon dioxide evolution and the rate of loss of all three herbicides in both soils, although the reduction in degradation rate of metamitron was small. The antibacterial antibiotic novobiocin enhanced carbon dioxide evolution from both soils but had variable effects on the rates of herbicide degradation. It inhibited degradation of metazachlor and metribuzin, and in one of the soils its effects on metazachlor degradation were similar to those of sodium azide. Novobiocin inhibited degradation of metamitron to a small extent in one soil only. The antifungal antibiotic cycloheximide also enhanced carbon dioxide evolution from both soils. In general, its effects on herbicide degradation were similar to those of novobiocin, although the extent of inhibition was usually less pronounced. The results are discussed in terms of the relative involvement of microorganisms in degradation of the three herbicides. 相似文献
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Helicoverpa armigera collected from cotton growing areas of South Sulawesi, Indonesia in 1987 and early 1988 were resistant to cypermethrin. It is suggested that the 86-fold resistance to cis-cypermethrin in 1987 and the 65-fold resistance to cis/trans-cypermethrin in 1988 are consistent with this being a major cause of failure to control the insects in cotton in this area. The second laboratory generation showed a 20-fold resistance to fenvalerate. The larvae collected in 1988 additionally had a 203-fold resistance to DDT and a 5.6-fold resistance to endosulfan. The results are discussed in relation to the fact that this is a further region in which Helicoverpa armigera has developed resistance to a number of pyrethroids. 相似文献