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991.
革兰阴性菌外膜囊泡的研究进展 总被引:1,自引:0,他引:1
外膜囊泡(outer membrane vesicles,OMVs)是革兰阴性(G^-)菌从细胞膜上脱落下来的囊泡,携带有细菌的大量组分,如外膜蛋白、脂多糖、脱氧核糖核酸等。由于OMVs无活性、不能复制且具有免疫原性,所以被认为是最具潜力的亚单位疫苗,同时OMVs对细菌本身具有多种作用,故OMVs成为研究的热点。本文从G^-菌OMVs的组成成分、形成机制、生物学功能、提取纯化方法及其开发应用前景5个方面综述其研究现状,为G^-菌的致病机制研究、OMVs的疫苗开发应用提供技术指导。 相似文献
992.
This experiment was conducted to study the effect of different rearing conditions of indoor and outdoor in winter and summer on growth performance and immune function of Heijiao MA chicken.In the winter and summer, 180 Heijiao MA chicken with the age of 35-day-old were chosen and randomly divided into two groups with three replicates per group and 30 chickens per replicate.The Heijiao MA chicken were reared at outdoor and indoor, respectively, and at 49, 63, 77, 91 days the immune organ indexes, serum antibody titers and growth performance were measured.The results showed that:①Whether it was winter or summer, the body weight of Heijiao MA chicken rearing at indoor were higher than that of outdoor, and the difference was significant at experimental stages in winter (P<0.05).There was significant difference only at 77 days old of Heijiao MA chicken in summer (P<0.05), the rest were not significant (P>0.05);②The ADG of outdoor group in summer was higher than that in winter, while the F/G of outdoor group in summer were significantly lower than that in winter (P<0.05).The ADFI and ADG of indoor group were not significantly different between winter and summer (P>0.05).③On immune function, immune organ indexes and ND antibody titer of Heijiao MA chicken of indoor group in winter were higher than outdoor group, while part of immune organ indexes, AI (H5) and ND antibody titers of outdoor group in summer were higher than that of indoor group;And ND and AI (H5) antibody titers in winter were higher than summer.In conclusion, The climate and season were major factors to influence the growth performance and immune function of Heijiao MA chicken. 相似文献
993.
肺气虚证小鼠模型造模方法及其对小鼠免疫功能的影响 总被引:1,自引:0,他引:1
为筛选肺气虚证小鼠模型最佳造模方法并验证其免疫功能变化,分别选用SO2法、SO2+寒冷因素刺激法、香烟烟熏法和香烟烟熏+寒冷因素刺激法重建肺气虚证小鼠模型,检测其体重、肺脏剖检及病理组织变化等指标,筛选最佳造模方法,并测定其腹腔巨噬细胞活性、体外B细胞抗体分泌能力、血清NO含量、淋巴细胞增殖能力及细胞因子IL-2、IL-4、IL-6、IL-10、IFN-γ、TNF-α含量、肺匀浆中sIgA、sIgM水平。结果显示,香烟烟熏+寒冷因素刺激法小鼠造模完成后出现严重的肺出血、肺组织坏死及炎性细胞浸润等病变,且与对照组小鼠相比,其体重、脾脏指数、胸腺指数分别显著下降18.35%,37.12%,19.69%,肺脏指数显著升高12.73%;小鼠腹腔巨噬细胞活性(P<0.01)、血清NO水平下降(P<0.05);T、B淋巴细胞增殖能力显著升高;细胞因子IL-2(P<0.01)、IFN-γ、IL-4含量升高(P<0.05),IL-6含量下降(P<0.05);sIgA、sIgM水平均极显著升高。表明,香烟烟熏+寒冷因素刺激法是肺气虚小鼠模型最佳造模方法,且其免疫功能受损。 相似文献
994.
995.
在当今生活审美化和社会网络化的新时代,图书资料的系列工作更要适应社会和时代发展的需求。同时,进一步廓清图书资料场所的基本功能,突显其存在价值与意义,才能更好发挥其在教育、服务和审美等方面的积极作用。本文对图书资料场所的基本功能进行探讨,希望能在同行之中起到抛砖引玉之效。 相似文献
996.
Kang JH Yang MP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(5):1166-1173
Background: The use of soybean oil-based lipid emulsion (SO-based LE) in parenteral nutrition has been reported to impair neutrophil functions in humans and rodents. As yet, little is understood about the effects of SO-based LE on canine immune responses.
Hypothesis: A short-term infusion with SO-based LE affects the phagocytic responses of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs).
Animals: Twenty-four healthy Beagle dogs.
Methods: Experimental study. Dogs were randomly assigned into groups of six and administered a 2-hour IV infusion with 0.9% NaCl solution or sufficient SO-based LE (INTRALIPOS 20%) to supply 40, 100, and 200% of the basal energy requirement (BER). PMN functions were determined after collecting blood samples before, immediately after, and 24 hours after the infusion.
Results: None of the treatments significantly affected the phagocytic capacity of PMNs or circulating leukocyte numbers. The infusion providing 200% of BERs significantly reduced PMN oxidative burst activity, filamentous actin polymerization, and Cdc42 Rho guanosine triphosphatase activity immediately after its delivery. However, these functions were restored to pre-infusion values 24 hours after the infusion. The lower calorie infusions did not have these effects.
Conclusions and Clinical Importance: These results suggest that short-term infusions with a supraphysiological dose of SO-based LE may decrease the immune functions of canine PMNs. However, more long-term studies will be needed to extrapolate the effect of SO-based LE with clinically relevant doses in a practical situation. 相似文献
Hypothesis: A short-term infusion with SO-based LE affects the phagocytic responses of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs).
Animals: Twenty-four healthy Beagle dogs.
Methods: Experimental study. Dogs were randomly assigned into groups of six and administered a 2-hour IV infusion with 0.9% NaCl solution or sufficient SO-based LE (INTRALIPOS 20%) to supply 40, 100, and 200% of the basal energy requirement (BER). PMN functions were determined after collecting blood samples before, immediately after, and 24 hours after the infusion.
Results: None of the treatments significantly affected the phagocytic capacity of PMNs or circulating leukocyte numbers. The infusion providing 200% of BERs significantly reduced PMN oxidative burst activity, filamentous actin polymerization, and Cdc42 Rho guanosine triphosphatase activity immediately after its delivery. However, these functions were restored to pre-infusion values 24 hours after the infusion. The lower calorie infusions did not have these effects.
Conclusions and Clinical Importance: These results suggest that short-term infusions with a supraphysiological dose of SO-based LE may decrease the immune functions of canine PMNs. However, more long-term studies will be needed to extrapolate the effect of SO-based LE with clinically relevant doses in a practical situation. 相似文献
997.
998.
为测定溪黄草对三黄肉仔鸡免疫功能的影响,将1日龄三黄肉仔鸡210只随机分为7组,每组3个重复,每个重复10只。Ⅰ组饲喂基础日粮,Ⅱ组添加0.2%恩诺沙星,Ⅲ组添加1%双黄连。Ⅳ-Ⅶ组分别在日粮上添加0.5%、1%、2%和4%溪黄草。分别测定免疫器官指数、新城疫HI抗体滴度和T淋巴细胞转化0D57。值。结果显示,溪黄草以2%剂量添加时可不同程度地刺激28日龄前三黄肉仔鸡的免疫器官发育,延长ND—HI抗体存留时间和抑制T淋巴细胞增殖,其它添加剂量对三黄肉仔鸡免疫功能也产生一定影响。 相似文献
999.
胰高血糖素样肽-I(GLP-1)是一种近年发现的胃肠激素,具有促进动物胰岛素分泌,刺激生长抑素释放,抑制胃酸产生与延长胃排空等生理功能。本文主要就GLP-1的生物学特性、生理调节功能及其应用前景作一阐述。 相似文献
1000.
黄芩甙对断奶仔猪生产性能和免疫机能的影响研究 总被引:2,自引:0,他引:2
将96头杜×长×大三元杂交断奶仔猪随机分为4组,每组设3个重复。第1组为对照组,饲喂基础日粮;第2组在基础日粮中添加0.006%的喹乙醇;第3组在基础日粮中添加0.05%的黄芩甙;第4组在基础日粮中添加0.006%的喹乙醇和0.05%的黄芩甙,探讨黄芩甙与仔猪免疫机能的关系。结果表明:第2、3、4组血清中总蛋白I、gG水平与第1组相比有升高的趋势(P>0.05);第2、4组的白球比值显著低于第1组(P<0.05),3组白球比值也低于1组(P>0.05);第2、3、4组T3、C4、GH水平显著高于第1组(P<0.05),而C3、T4水平有升高的趋势,但差异不显著(P>0.05),皮质醇含量显著低于第1组(P<0.05)。试验结果表明,在早期断奶仔猪日粮中添加黄芩甙具有改善免疫机能的作用,有助于提高仔猪抗病力。 相似文献