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91.
Shu Q Hillard MA Bindon BM Duan E Xu Y Bird SH Rowe JB Oddy VH Gill HS 《American journal of veterinary research》2000,61(7):839-843
OBJECTIVE: To determine efficacy of vaccines incorporating QuilA, alum, dextran combined with mineral oil, or Freund adjuvant for immunization of feedlot cattle against Streptococcus bovis and Lactobacillus spp. ANIMALS: 24 steers housed under feedlot conditions. PROCEDURE: Steers were randomly assigned to 4 experimental groups and a control group. Animals in experimental groups were inoculated on days 0 and 26 with vaccines containing Freund adjuvant (FCA), QuilA, dextran combined with mineral oil (Dex), or alum as adjuvant. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were measured, along with fecal pH, ruminal fluid pH, and number of S bovis and Lactobacillus spp in ruminal fluid. RESULTS: Throughout the study, serum anti-S bovis and anti-Lactobacillus IgG concentrations for animals in the Dex, QuilA, and alum groups were similar to or significantly higher than concentrations for animals in the FCA group. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were significantly increased on days 26 through 75 in all 4 experimental groups, and there was a linear relationship between anti-S bovis and anti-Lactobacillus IgG concentrations. For animals in the QuilA and Dex groups, mean pH of feces throughout the period of experiment were significantly higher and numbers of S bovis and Lactobacillus spp in ruminal fluid on day 47 were significantly lower than values for control cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that immunization of feedlot steers against S bovis and Lactobacillus spp with vaccines incorporating Freund adjuvant, QuilA, dextran, or alum as an adjuvant effectively induced high, long-lasting serum anti-S bovis and anti-Lactobacillus IgG concentrations. Of the adjuvants tested, dextran may be the most effective. 相似文献
92.
苍耳等药用植物提取物对小菜蛾的拒食作用和产卵忌避效果 总被引:16,自引:0,他引:16
室内采用叶碟法,研究苍耳(Xanthium sibiricumPetril)等8种药用植物乙醇提取物对小菜蛾(Plutel-la xylostella)的拒食和产卵忌避活性。结果表明,苍耳(果实)、雷公藤(根)和商陆(根)乙醇提取物对小菜蛾4龄幼虫的取食均有较强的抑制作用,选择性拒食率分别为86.16%、49.06%和43.82%;非选择性拒食效果仍以苍耳(果实)提取物最好,达45.23%。选择性产卵忌避率以雷公藤(根)提取物为最高(69.52%),其次是苍耳(果实)和山苍树(枝叶)提取物,分别为62.50%和57.72%,雷公藤(根)、商陆(根)、窃衣(茎叶)和苍耳(果实)的非选择性产卵忌避作用均在77%以上。苍耳和雷公藤提取物在对小菜蛾的拒食和产卵忌避的各测试中,均表现较强活性。 相似文献
93.
94.
Toshiyuki Usami Shu Ishigaki Hiroko Takashina Yuko Matsubara Yoshimiki Amemiya 《Journal of General Plant Pathology》2007,73(2):89-95
Japanese isolates of Verticillium dahliae, a causal agent of wilt disease in many plants, are classifiable into pathotypes based on their pathogenicity. Because these
pathotypes are morphologically indistinguishable, establishing a rapid identification method is very important for the control
of this pathogen in Japan. For cloning DNA fragments that are useful for identification and specific detection of V. dahliae pathotypes, we performed random amplified polymorphic DNA (RAPD) analyses using various isolates. One polymerase chain reaction
(PCR) product, E10-U48, was specific to isolates pathogenic to sweet pepper. The other product, B68-TV, was specific to race
1 of isolates pathogenic to tomato. The specificity of these sequences was confirmed by genomic Southern hybridization. Further
analyses revealed that the region peripheral to B68-TV obtained from the genomic DNA library includes the sequence specific
to all isolates pathogenic to tomato (races 1 and 2). Moreover, sequence tagged site (STS) primers designed from B68-TV and
its peripheral region showed race-specific and pathotype-specific amplification in a PCR assay. The probes and primers obtained
in this study are likely to be useful tools for the identification and specific detection of pathotypes and races of V. dahliae.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB095266. 相似文献
95.
Kang Lan-ying Shu Jian-hua 《农业科技与信息》2007,(9)
应2008奥运会的需求,象征中国喜庆的红色花卉的繁育成为热点。本文提出一串红的良种繁育制度和种子生产技术规程,并以新品种的良种繁育为核心,开展了相关研究,以供良种的繁育。 相似文献
96.
WANG Hong WU Jin-min CAO Hou-jun ZHOU Wen-peng FANG Yong ZHANG Xing ZHENG Shu 《园艺学报》2006,22(6):1218-1221
AIM:To evaluate the relationship between u PA and NF-κB p65 expression and its clinical significance in breast cancer.METHODS:The uPA mRNA was measured by real-time fluorescent quan t itative PCR in 46 cases of breast cancer tissues and their adjacent counterparts .NF-κB p65 were measured using immunohistochemistry.RESULTS:The expression of uPA gene was elevated in 63% of cases ,and there was a strong correlation between NF-κB p65 and uPA expression (r =0.451,P<0.01).In addition,the expression of uPA was associated with num bers of axillary lymph node involvement and tumor size.However,no significance was found in uPA expression in the age,pathological type and distant metastasi s organ classification.CONCLUSION:The uPA gene is highly expressed in most of the brea st cancer,and there is strong correlation to NF-κB p65 expression,number of l ymph nodes involvement and tumor size. 相似文献
97.
98.
立桶式家用热泵热水器冷凝器性能的研究 总被引:1,自引:0,他引:1
针对华南地区的气候特点,用同样管径和长度的高导热耐腐蚀不锈钢管绕成等径螺旋盘管和非等径螺旋盘管作为家用热泵热水器的沉浸式冷凝器,并对其传热特性进行了对比分析和实验研究.结果表明,在同等环境条件下,加热90 L立桶式静态水至50℃,非等径螺旋盘管的综合效果优于等径螺旋盘管;加热3 L/min流量的立桶式动态水,采用非等径螺旋盘管的平均出水温度比等径螺旋盘管大约高1℃. 相似文献
99.
试论草业系统工程结构 总被引:1,自引:0,他引:1
草业系统工程的结构是有关草业发展的战略问题。重点阐述了下述意见:1.草业与农林三者鼎立,不同于以往的农林牧提法。一字之差,不仅提高了草业在大农业上的地位,而且扭转了只重有实利可图的畜,而把其基础第一性的草业抛于脑后的逐利忘本、置草原退化荒废于不顾的思想根源。种草才能获得畜牧业的合理持续发展。2.在振兴草业的诸项大纲中栽培草本最受重视。不仅项目较多,而且那些与人、畜应用有共轭关系的受到特别强调。因为这是提高草地畜牧业产值的一条重要途径。3.把灌木(灌丛)纳入草业合乎草地类型和家畜食性的实际,是扩大草业资源、保护草原的战略措施。同时,把混牧林和林产品采食的现有习惯看作草和林的结合与联系,而不必勉强划归草业。 相似文献
100.