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61.
2型猪链球菌的血清学鉴定 总被引:41,自引:0,他引:41
本试验首次证实了2型猪链球菌在我国的存在,采用玻片凝集、琼脂扩散及毛细管沉淀等3项试验,对1990年以来广东某猪场断奶仔猪暴发流行的败血症、脑膜炎及关节炎病猪中分离的15株链球菌进行了血清学鉴定。结果表明:15株链球菌均为2型猪链球菌;用高压法提取抗原进行沉淀反应,其结果比酸热法提取抗原具有简便、敏感、特异性强的特点。 相似文献
62.
Rob W. Briddon Patricia Lunness Ian D. Bedford Leony C. L. Chamberlin Theo Mesfin Peter G. Markham 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(4):397-400
The cause of a streak disease of pearl millet (Pennisetum glaucum), originating from Nigeria, has been attributed to a geminivirus belonging to the African streak virus cluster. A full-length, infectious clone of the virus was obtained which was transmissible by the vectorCicadulina mbila (Naudé). Analysis of the complete nucleotide sequence of the coat protein gene of this virus shows it to be most closely related to sugarcane streak virus. The possible evolutionary implications of this finding are discussed. 相似文献
63.
K. Tagata S. Yokoyama T. Ginbo M. Honda T. Okimura M. Odakura M. Nomura S. Yamamoto 《Veterinary research communications》1996,20(1):21-30
A capillary reversed passive latex agglutination test (capillary RPLA) was developed which allows quantification of serum C-reactive protein (CRP) within approximately 15 min. The logarithmic regression line (calibration curve) obtained after measuring each CRP concentration three times in twofold dilutions of a standard canine serum containing 222 g/ml of CRP was y=6.394+0.030x (r=0.995). Capillary RPLA permitted quantification of CRP in the range 6.9–222 g/ml. The coefficients of variation ranged from 10.28% to 12.40%. The recovery rates (percentage recovery) of CRP by capillary RPLA were within the range 87% to 106%. On measuring the CRP concentrations in sera from 78 dogs by capillary RPLA, single radial immunodiffusion (SRID) and enzyme-linked immunosorbent assay (ELISA), close correlations were demonstrated between SRID and capillary RPLA (y=7.250+1.109x, r=0.978), between SRID and ELISA (y=3.042+1.059x, r=0.967), and between capillary RPLA and ELISA (y=1.778+0.929x, r=0.962). Capillary RPLA may be considered useful as a routine biochemical technique for measurement of serum CRP concentration in the dog.Abbreviations CRP
C-reactive protein
- ELISA
enzyme-linked immunosorbent assay
- RPLA
reversed passive latex agglutination test
- SRID
single radial immunodiffusion 相似文献
64.
应用种子蛋白电泳图谱对高羊茅品种进行鉴别与聚类研究 总被引:2,自引:2,他引:0
利用种子贮藏蛋白进行二二烷其磺酸钠-聚丙烯酰胺凝脉电泳,对23个高羊茅品种进行了 分析。表明该方法成本低,效率高,重复性好,能有效地反应高羊茅品种的遗传差异和亲缘关系。电泳谱带聚类分析所得到的类群,能代表生产上,饲用,草坪用类型以及两种用途中的主要生态类型。 相似文献
65.
N. Katoh 《Veterinary research communications》1994,18(6):423-432
Protein kinase C (PKC) activity was evaluated and the phosphorylation of its endogenous substrates was explored in fatty liver induced by administration of ethionine (an analogue of methionine) to cows in order to assess the relevance of PKC-dependent phosphorylation in the development of fatty liver. PKC activity was decreased in both the cytosolic and the total particulate fractions from fatty livers, compared to the corresponding fractions from control liver. The mode of activation by the PKC cofactors (1-oleoyl-2-acetyl-sn-glycerol, 12-O-tetradecanoylphorbol-13-acetate, phosphatidylserine and Ca2+) was similar in both control and fatty livers, suggesting a quantitative but not a qualitative change in PKC in fatty liver. At least three substrate proteins (34 kDa, 26 kDa and 19 kDa) were found in the cytosolic fraction and their phosphorylation was reduced in fatty liver. These results suggest that impairment of the signal transduction pathway mediated by PKC is involved in the pathogenesis of fatty liver in cows.Abbreviations ATP
adenosine triphosphate
- EGTA
ethylene glycol bis(-aminoethylether)-N,N,N,N-tetraacetic acid
- NEFA
non-esterified fatty acid
- OAG
1-oleoyl-2-acetyl-sn-glycerol
- PKC
protein kinase C
- PS
phosphatidylserine
- SDS-PAGE
sodium dodecyl sulphate-polyacrylamide gel electrophoresis
- TG
triglyceride
- TPA
12-O-tetradecanoylphorbol-13-acetate 相似文献
66.
INTRODUCTIONIntheworldoftoday,theglobalclimatechangeanditsinfluenceonecologyhavebe-comeaveryimportantproblem,towhichmanyscientists,governnentleadersandordinarypcoplepaycloseattentionI1-'].Inl979,theWorldClimateResearchProgram(WCP)waslaiddowninthefirstworldclimatemeeting.lnl99(),thesecondworldclimatemeetingwasconvcl1edinGencva,andalltl1eexpertsagreedthattheglobalwarmlngwillbeextremelyseriousdisasterthananynatUralcalamityever.Attl1eMectingof"WorldEnvironmentandDevelopment,"holdinBrazil… 相似文献
67.
G. Jager H. Velvis 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(4):467-478
The position of plants withRhizoctonia solani sclerotia (black scurf) on progeny tubers was mapped for an experimental field at Haren where potatoes were grown continuously and in rotation with other crops for five successive years, and for another field at Borgercompagnie with a 12 frequency of potatoes during three potato crops. Initially, the distribution of plants with black scurf on both fields was rather dense and homogeneous. In the following years the distribution became heterogeneous and patchy. The local decline ofR. solani AG 3 (the common potato pathogen) in Haren was apparently caused by an unknown factor selectively suppressingR. solani AG 3, while simultaneouslyR. solani AG 5 increased in mass. This AG 5 type proved to be an inferior competitor of AG 3 on the potato plant in a laboratory experiment. The specificR. solani antagonistVerticillium biguttatum did not play a role. A similar factor could have reduced the formation of black scurf in the experimental field at Borgercompagnie, whereV. biguttatum was also too infrequent to account for the decline.R. solani AG 5 was not present here and could not indicate the presence of a selective factor against AG 3. 相似文献
68.
South-Westerm blot mapping是一种结合Western blotting和Southern blotting某些特点的方法.本文介绍用其成功地观察到锥虫核蛋白中DNA结合蛋白的情况,并对一个分子量在40000左右、于较严谨条件下与DNA结合的核蛋白进行了特性鉴定.该蛋白等量地存在于锥虫的前循环期和血液期,对双链DNA有较大的亲和力,并能与酵母菌复制起始片段结合.本文还介绍了锥虫细胞核的提取技术和核蛋白的制备技术. 相似文献
69.
70.
蛋白质组学研究技术及其在果树学中的应用 总被引:7,自引:3,他引:7
蛋白质组研究是当今生命科学发展的一个新的增长点,它能阐明基因组所表达的真正执行生命活动的全 部蛋白质的表达规律和生物功能。简要介绍了蛋白质组学产生的科学背景、研究方法和研究内容。蛋白质组学研究 方法主要有双向聚丙烯酰胺凝胶电泳(2D-PAGE)、质谱(Mass-spectrometric)技术、蛋白质芯片(Protein chips)技术、酵母 双杂交系统(Yeast two-hybrid system)、双向高效柱层析和生物信息学等。其应用的范围包括植物群体遗传学、在个体 水平上植物对生物和非生物环境的适应机制、植物的发育和组织器官的分化过程,以及不同亚细胞结构在生理生态 过程中的作用等诸多方面。同时展望了植物蛋白质组学研究前景以及蛋白质组学技术在果树学中的应用前景。 相似文献