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排序方式: 共有347条查询结果,搜索用时 15 毫秒
161.
162.
Xiao-ming Yang Wei Yu Zhong-ping Ou Hai-le Ma Wei-ming Liu Xue-lin Ji 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):167-173
The antioxidative activities of water extract (WE) and crude hot-water soluble polysaccharide (PS) from Ficus carica L. fruit were investigated using various assays in vitro, including scavenging abilities on DPPH, superoxide and hydroxyl radicals and reducing power. The immunity activities of
PS were evaluated using the carbon clearance test and serum hemolysin analysis in mice. In addition, total phenolics and flavonoids
contents were also determined. Both WE and PS have notable scavenging activities on DPPH with the EC50 values of 0.72 and 0.61 mg/ml, respectively. The PS showed higher scavenging activity than WE on superoxide radical (EC50, 0.95 mg/ml) and hydroxyl anion radical (scavenging rate 43.4% at concentration of 4 mg/ml). The PS (500 mg/kg) also has
a significant increase in the clearance rate of carbon particles and serum hemolysin level of normal mice. The results indicate
that both WE and PS might be applicable in healthy medicine and food industry. 相似文献
163.
164.
Qiuyue Wang Jianhua Li Xichen Zhang Quan Liu Chengwu Liu Guangpeng Ma Lili Cao Pengtao Gong Yanan Cai Guocai Zhang 《Veterinary parasitology》2009,160(3-4):198-203
Two recombinant Mycobacterium bovis BCG (rBCG) strains carrying the Eimeria tenella rhomboid gene (Rho) delivered by extrachromosomal vector pMV261 and integrative vector pMV361 were evaluated for their ability to protect chickens against E. tenella challenge. The chickens were immunized intranasal with BCG, rBCG pMV261-Rho, or rBCG pMV361-Rho twice at a 2-week interval. All the recombinant BCG immunized chickens developed specific immune responses, and there was a significant increases of the percentages of CD4+ and CD8+ cells compared to the control (P < 0.05). Challenge experiments demonstrated that the two rBCG strains could provide significant protection against E. tenella challenge. But vaccination with rBCG pMV261-Rho induced higher specific antibody titers and produced greater protection rate (56.04%) than rBCG pMV361-Rho group (P < 0.05). These results indicated that M. bovis BCG is a novel vaccine vector to express and present antigens of E. tenella, and rBCG has a potential as vaccine in chickens. 相似文献
165.
《动物营养(英文)》2021,7(3):770-778
To reduce nitrogen excretion and lower feeding costs, low crude protein (CP) diets are sometimes proposed, however, a great reduction of dietary CP concentration (>4% reduction vs. recommended concentration), even supplemented with essential and nonessential amino acids (AA) can detrimentally affect small intestinal barrier function and immunity, possibly due to the excessive lack of peptides. Here we hypothesize that with an extremely low CP concentration diet, protein-derived peptides, rather than AA supplementation, can improve intestinal barrier development and health. To test this hypothesis, 21 growing pigs (19.90 ± 1.00 kg body weight) were randomly assigned to 3 treatments with control diet (16% CP), or low CP diets (13% CP) supplemented with AA (LCPA) or casein hydrolysate (LCPC) for 28 days. In comparison with the control diet, the LCPA diet decreased the protein expression level of jejunal barrier factor zonula occludens-1 (ZO-1) and stem cell proliferation factor leucine-rich repeat-containing G-protein-coupled receptor-5, whereas the LCPC diet enhanced intestinal barrier function by increasing the protein expression level of jejunal occludin and ZO-1 and ileal mucin-2. The LCPA diet reduced Lactobacillus counts, whereas the LCPC diet increased Lactobacillus counts and reduced Escherichia coli counts in the ileum. The LCPA diet also increased protein expression levels of pro-inflammatory cytokine interleukin-6 (IL-6) and IL-22, whereas the LCPC diet decreased protein expression levels of pro-inflammatory IL-1β, IL-17A and tumor necrosis factor-α in the ileum. Collectively, the casein hydrolysate supplementation of low CP diets showed beneficial effects on the small intestinal barrier, bacterial community, and immunity in pigs, pointing to the important role of protein-derived peptides in small intestinal health in cases of low crude protein diets. 相似文献
166.
采用提高雏鸡应激能力、预防药物抵御环境污染、早期免疫激活等综合防制技术进行育雏试验。结果表明,试验Ⅰ组海兰W-36商品蛋鸡49日龄雏鸡成活率、健雏率分别比对照组高83和49个百分点,降低成本67%;伊莎褐商品蛋鸡49日龄成活率、健雏率分别比对照组高72和45个百分点,降低成本54%。试验Ⅱ组海兰W-36商品蛋鸡49日龄成活率、健雏率分别比对照组高83和44个百分点,降低成本6.9%;伊莎褐商品蛋鸡49日龄成活率、健雏率分别比对照组高70和45个百分点,降低生产成本51%。使用高维E电解多维可有效降低早期雏鸡逆境应激。 相似文献
167.
本试验旨在研究日粮中添加不同水平包膜半胱胺(CCS)对肥育猪生长性能、免疫和抗氧化能力及十二指肠消化酶活性的影响。选择体重(62.12±1.43)kg的健康杜×长×大肥育猪160头,随机分为4个处理,每个处理组4个重复,每个重复10头(公、母各半)。对照组饲喂基础日粮,试验组在基础日粮的基础上分别添加100、200、400 mg/kg CCS。试验猪自由采食饮水,预试期5 d,正试期40 d。结果表明:CCS对肥育猪的平均日增重(ADG)、平均日采食量(ADFI)和耗料增重比(F/G)无显著影响,但100 mg/kg CCS组生长性能指标相对最佳;100、200 mg/kg CCS组血清IgM和补体C3水平均上升(P<0.05),C3水平随着CCS添加剂量的提高呈线性上升(P<0.05);CCS有提高血清Ig G水平的趋势(P=0.07),并呈二次升高(P<0.05);CCS提高了血清中总抗氧化能力(T-AOC)并呈二次变化(P<0.05);血清谷胱甘肽过氧化物酶(GSH-Px)水平和过氧化氢酶(CAT)活性随着CCS水平的提高呈线性及二次变化(P<0.05);肝脏GSH-Px和总超氧化物歧化酶(T-SOD)活性随着CCS水平的提高呈线性及二次增高(P<0.05);CCS提高了十二指肠总蛋白酶和总脂肪酶活性(P<0.05),使总淀粉酶活性呈二次上升(P<0.05)。可见,日粮中添加低剂量的CCS对肥育猪生产性能有一定改善趋势,CCS可提高肥育猪的免疫和抗氧化性能,促进肠道消化酶的分泌。在本试验中,CCS在肥育猪饲粮中的适宜添加水平为100 mg/kg。 相似文献
168.
2~3月龄肉兔粗蛋白水平对营养物质利用、肉品品质及免疫指标影响的研究 总被引:2,自引:0,他引:2
选用50只2月龄新西兰肉兔随机分为5组,各组日粮的粗蛋白(CP)水平分别为14%、16%、18%、20%和22%,观察日粮粗蛋白对2~3月龄新西兰兔营养物质利用、肉质及免疫指标的影响。结果表明:2~3月龄肉兔营养物质消化率随蛋白水平的提高先上升后下降,其中CP消化率以20%CP组最高,为74.43%;粗纤维消化率以16%CP组最高,为32.34%;必需氨基酸中甘氨酸、赖氨酸、亮氨酸、苏氨酸、缬氨酸、组氨酸和苯丙氨酸的消化率以18%或20%CP组最高。日粮蛋白水平对肉兔肌肉的化学组成影响不大,剪切力和系水力以20%CP组最低和最高,分别为961.53g/cm2和73.12%;3月龄肉兔的脾脏指数和胸腺指数蛋白水平为20%时最高,分别为0.89和2.60。 相似文献
169.
P. Lesaver J. F. Bach 《Comparative immunology, microbiology and infectious diseases》1980,3(4):391-406
An increasing number of substances is capable of potentiating immune responses. These can be grouped into several categories: bacterial products, leucocyte extracts (transfer factor, interferon) thymic hormones and synthetic drugs (levamisole). Their therapeutic use against infections is still uncommon for several reasons. First, the immunostimulants, particularly the bacterial extracts have many toxic side-effects. Second, most of them have not been obtained under pure and chemically-characterized form. Third the mechanisms of immunostimulation are not completely understood and depending on the route and the timing of injection, the immunostimulants can exhibit suppressive activities. For these reasons a larger use of immunostimulant substances requires purified or synthetic materials, careful experimental and clinical analysis of their effects and rigorous indications. These conditions are already fulfilled for some immunostimulants especially in immunodeficient virus-infected patients. 相似文献
170.