Sequence and analysis of genomic segment A and B of very virulent infectious bursal disease virus isolated from China     

Sun JH  Lu P  Yan YX  Hua XG  Jiang J  Zhao Y 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(3):148-154

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宁夏苜蓿病虫害发生现状及防治对策   总被引：33，自引：10，他引：23  

张蓉  马建华  王进华  任学山 《草业科学》2003,20(6):40-44

通过2001—2002年的田间调查和室内鉴定,明确了宁夏苜蓿病虫害的发生种类、分布和危害程度。目前,在宁夏苜蓿生产中大面积发生并引起灾害性损失的害虫为蚜虫、蓟马、草地螟、象甲和潘叶蝇,病害为苜蓿褐斑病、霜霉病、白粉病和花叶病,并提出相应的防治对策。  相似文献   

鸡骨型白血病免疫琼扩与放射摄片诊断的比较   总被引：1，自引：1，他引：0  

陈白希  白朝勇  单玉萍  岳学民  詹国英  吴玄光  詹耀明  钟奋军  林景坤  黎建荣 《中国兽医学报》2003,23(5):490-492

为了探索特异性免疫学诊断方法对鸡骨型白血病(OP)的检测效果。用双盲法分批采样同时进行羽髓琼脂扩散试验和胫骨X线摄片检查对比,共检834只鸡(433羽属天然自发OP鸡群,401羽属人工诱发实验鸡群)。结果羽髓琼扩试验的OP阳性检出率为3．48％(29／834：)。阳性病理符合率为75．86％(22／29)。阳性误诊(假阳性)率24．13％(7／29),阴性误诊(假阴性)率36．15％(291／805)。而X线摄片检查的OP阳性检出率为38．37％(320／834)。X线阳性完全可获病理组织学证实,不存在假阳性或假阴性。把禽白血病羽髓琼扩试验试用于检测鸡骨型白血病尚属初次报道,其阳性检出率低而误诊率高,尚不宜作OP检测手段。放射摄片诊断的阳性检出率高而误诊率低,可快速诊断,故适用于OP检疫。  相似文献   

茶秆竹高生长模型的比较及组合选择   总被引：2，自引：1，他引：1  

代全林  陈存及  肖书平  陈东阳  董建文 《福建林学院学报》2002,22(2):129-132

通过对 5种 S增长模型的比较及组合选择 ,结果表明 :S增长模型都具有单调性、渐近性和拐点 ,此特征能客观地反映诸多自然和经济规律 .通过一定的加权组合 ,用多个增长模型来反映 S变化过程 ,可以提高拟合的精度 ,多个模型的组合要优于单个模型 .用加权模型可以很好地反映茶秆竹的高生长过程 ,在实际生产中可选择 yp2 或 yp 3 组合  相似文献   

Evaluation of L-selectin expression and assessment of protein tyrosine phosphorylation in bovine polymorphonuclear neutrophil leukocytes around parturition   总被引：3，自引：0，他引：3  

Monfardini E  Paape MJ  Wang Y  Capuco AV  Husheem M  Wood L  Burvenich C 《Veterinary research》2002,33(3):271-281

Impaired polymorphonuclear neutrophil leukocyte (PMN) function around parturition has been associated with increased clinical mastitis in dairy cows. Rolling and attachment of PMN to the endothelium is the first step in the recruitment process and is accomplished by interaction between L-selectin on PMN and its ligand on endothelial cells. Furthermore, tyrosine phosphorylation is involved in the initiation of many PMN functions. The objective of this work was to determine changes in expression of L-selectin and tyrosine phosphorylation in the perinatal period. Eight clinically healthy Holstein cows were used as PMN donors at d-21, -14, -7,0 (calving), +1, +2, +7, +14, +28. Evaluation of L-selectin expression was carried out on activated and resting PMN. Anti-bovine L-selectin monoclonal antibody (MAB) and flow cytometric analysis were used to measure the percentage of PMN fluorescing and receptor expression (log mean fluorescent channel, LMFC). Activated and resting PMN showed similar trends in % PMN fluorescence and LM FC. The percentage of PMN fluorescing tended to decrease at parturition, followed by a significant increase at d +14 and +28 (P < 0.02). For LMFC a decrease was observed on d +1 followed by an increase through d +28 (P < 0.01). Protein tyrosine phosphorylation of lysates prepared from PMN isolated throughout the study was detected by electrophoresis and western blotting using anti-phosphotyrosine MAB. Several protein bands were tyrosine phosphorylated. Two of these bands (42-44 kDa and 90 kDa) varied in intensity over time. The intensity of the 42-44 kDa band gradually increased from d -7, peaked at d +7 (P < 0.03), and steadily decreased to d +28 (P < 0.02). Antibody to activated mitogen protein kinase reacted with the 42-44 kDa band. Reduced PMN function during the periparturient period could be related to reduced L-selectin adhesion molecules on the cell surface, and to modulation in the phosphorylation of functionally important molecules.  相似文献   

Induced systemic protection against tomato late blight elicited by plant growth-promoting rhizobacteria     

Yan Z  Reddy MS  Ryu CM  McInroy JA  Wilson M  Kloepper JW 《Phytopathology》2002,92(12):1329-1333

ABSTRACT Two strains of plant growth-promoting rhizobacteria (PGPR), Bacillus pumilus SE34 and Pseudomonas fluorescens 89B61, elicited systemic protection against late blight on tomato and reduced disease severity by a level equivalent to systemic acquired resistance induced by Phytophthora infestans or induced local resistance by chemical inducer beta-amino butyric acid (BABA) in greenhouse assays. Germination of sporangia and zoospores of P. infestans on leaf surfaces of tomato plants treated with the two PGPR strains, pathogen, and chemical BABA was significantly reduced compared with the noninduced control. Induced protection elicited by PGPR, pathogen, and BABA were examined to determine the signal transduction pathways in three tomato lines: salicylic acid (SA)-hydroxylase transgenic tomato (nahG), ethylene insensitive mutants (Nr/Nr), and jasmonic acid insensitive mutants (def1). Results suggest that induced protection elicited by both bacilli and pseudomonad PGPR strains was SA-independent but ethylene- and jasmonic acid-dependent, whereas systemic acquired resistance elicited by the pathogen and induced local resistance by BABA were SA-dependent. The lack of colonization of tomato leaves by strain 89B61 suggests that the observed induced systemic resistance (ISR) was due to systemic protection by strain 89B61 and not attributable to a direct interaction between pathogen and biological control agent. Although strain SE34 was detected on tomato leaves, ISR mainly accounted for the systemic protection with this strain.  相似文献   

黄皮种子脱水敏感性与核酸、蛋白质代谢的关系   总被引：3，自引：0，他引：3  

王艳  李韶山  何军贤  傅家瑞 《园艺学报》2000,27(3):210-210

黄皮种子发育晚期,胚内核酸和蛋白质合成能力增强,而花生种子发育晚期则呈下降趋势。脱水处理使生理成熟期黄皮胚核酸和蛋白质合成能力急剧下降,核酸水解酶活性增强。生物大分子代谢能力的变化是黄皮种子脱水敏感性的分子基础。  相似文献   

神经内分泌因子、代谢产物对体外培养新生犊牛肝细胞胰高血糖素受体mRNA丰度的影响     

张永宏  高妍  孙玉成  刘国文  陈承祯  王哲 《中国草食动物》2007,27(6):3-6

为阐明神经内分泌因子胰岛素（In）、胰高血糖素（GLN）、瘦素（LEP）和代谢产物非酯化脂肪酸（NEFA）、β-羟丁酸（BHBA）、葡萄糖（GLU）在奶牛肝糖代谢、脂代谢中的调控作用，应用荧光定量PCR（fluorescent quantitative PCR）法观察了神经内分泌因子、代谢产物对体外培养新生犊牛肝细胞胰高血糖素受体（glucagon receptor，GLNR）mRNA丰度的影响。结果显示：随着培养液中In、NEFA、BHBA和GLU的升高，GI。NRmRNA表达逐渐增加（P〈0．01）；随着培养液中GLN浓度的升高，GLNRmRNA表达逐渐降低（P〈0．01）；而随着培养液中瘦素浓度的升高，GLNRmRNA的表达呈先升高后降低的趋势（P〈0．01）。表明：神经内分泌因子In、GLN、LEP和代谢产物NEFA、BHBA、GLU直接调控新生犊牛肝细胞GLNRIT／RNA的表达。  相似文献   

可发酵碳水化合物减少猪场臭气的机理和应用   总被引：2，自引：0，他引：2  

潘倩  陈安国  赵燕 《家畜生态学报》2007,28(3):6-10

可发酵碳水化合物,添加在猪日粮中到达后肠作为微生物发酵的底物,通过改变猪肠道和粪便中的微生物及其发酵过程,改变粪尿的理化特性,来减少氨的挥发以及臭气的产生.本文对臭气和除臭方法进行了简单的介绍,并综述了通过在猪日粮中添加可发酵碳水化合物来控制猪场臭气的机理和应用效果.  相似文献   

不同寡糖对肉仔鸡肠道主要菌群和免疫器官指数的影响   总被引：4，自引：2，他引：4  

袁缨  闫际平  陈立华  崔蕾 《中国饲料》2007,(15):15-17

为研究含糖量相同(0.015%)的不同种类寡糖对肉仔鸡肠道菌群和免疫机能的影响,本试验选用150只健康的1日龄艾维茵肉仔鸡(公母各半),随机分为5个处理,每个处理设3个重复,每个重复10只鸡。对照组饲喂基础日粮,试验组为分别在基础日粮添加果寡糖组(FOS)、甘露寡糖组(MOS)、低聚异麦芽糖组(GOS)、低聚木糖组(XOS),试验期为42d。试验结果表明:42日龄时,低聚木糖组对肠道菌群的改善效果最好;寡糖极显著提高了胸腺指数(P<0.01),且低聚木糖组极显著提高了法氏囊指数(P<0.01)。  相似文献