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111.
Barthel R Piedrahita JA McMurray DN Payeur J Baca D Suárez Güemes F Perumaalla VS Ficht TA Templeton JW Adams LG 《American journal of veterinary research》2000,61(9):1140-1144
OBJECTIVE: To determine necropsy and Mycobacterium bovis culture results in cattle from herds with tuberculosis, the role of the bovine NRAMP1 gene in resistance and susceptibility to infection with M bovis, and the association between magnitude of the tuberculous lesions and various types of M bovis isolates. ANIMALS: 61 cattle from herds with tuberculosis in Texas and Mexico. PROCEDURE: 61 cattle were evaluated by necropsy; 59 had positive and 2 had negative caudal fold tuberculin intradermal test (CFT) results. Thirty-three cattle with positive CFT results were genotyped to evaluate polymorphism of the 3' untranslated region of the bovine NRAMP1 gene, using single-stranded conformational analysis, 9 were resistant to M bovis with no tuberculous lesions and negative M bovis culture results, and 24 were susceptible with tuberculous lesions and positive M bovis culture results. Isolates of M bovis were analyzed by restriction fragment length polymorphism (RFLP) on the basis of IS6110 sequences and direct-repeat fingerprinting patterns. RESULTS: 21 (35.6%; 21/59) cattle with positive CFT results had tuberculous lesions or positive culture results; in addition, 1 of 2 cattle with negative CFT results had tuberculous lesions and positive culture results. Tuberculous lesions were most common in the thorax (35/63; 55.5%) and lymphoid tissues of the head (10/63; 15.9%). Tuberculous lesions varied from 1 to 11/animal; 8 of 21 (38.1%) had solitary lesions. Associations were not found between resistance or susceptibility to infection with M bovis and polymorphism in the NRAMP1 gene or between the magnitude of the lesions and various RFLP types of M bovis isolates. CONCLUSIONS AND CLINICAL RELEVANCE: The NRAMP1 gene does not determine resistance and susceptibility to infection with M bovis in cattle. 相似文献
112.
We used pressure-volume analysis and dewpoint hygrometry to determine leaf water relation parameters of mangrove (Avicennia germinans L.) seedlings grown at salinities of 0, 8, 20 and 32 per thousand. Seedlings responded to an increase in salinity from 0 to 32 per thousand by an increase in leaf succulence as reflected in an increase in leaf water content per unit area from 300 to 360 g m(-2). Additionally, osmotic potential at full turgor decreased from -2.3 to -3.5 MPa and osmotic potential at zero turgor decreased from -2.7 to -4.3 MPa. Cell elasticity decreased as salinity increased from 0 to 32 per thousand, as indicated by a progressive increase in volumetric modulus of elasticity from 19 to 27 MPa. Increased leaf succulence enabled leaves to sequester large amounts of solutes without adversely increasing cell osmotic pressure. On the other hand, osmotic adjustment facilitated turgor maintenance as water potential diminished. Salinity-induced decreases in tissue elasticity generated greater water potential differences between leaves and soil under saline conditions than under non-saline conditions. 相似文献
113.
Sánchez-Andrade R Paz-Silva A Suárez J Panadero R Díez-Baños P Morrondo P 《Veterinary parasitology》2000,93(1):39-46
An indirect-enzyme immune-linked immunosorbent assay (IEA) was compared to a sandwich-enzyme-linked immunosorbent assay (SEA) to diagnose fasciolosis in naturally infected cattle. By means of a rabbit polyclonal IgG antibody to F. hepatica antigens, captured circulating antigens were detected by an SEA technique. A total of 85.1% of the samples examined was considered positive by using the IEA-test, whereas this percentage was of 37.3% by the SEA test. Using the two enzymatic probes, only the 38.3% resulted positive to both immunoassay probes. Our data indicate that circulating antigen detection assay in combination with results of antibody detection may offer a more reliable diagnostic technique than classic coprologic ones, with results very appropriate for epidemiologic studies carried out on a wide area. 相似文献
114.
Suárez P 《Veterinary research》2000,31(1):47-55
Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) was first isolated in swine alveolar macrophages (SAMs) and has subsequently been reported to replicate in other cell lines. Entry of the virus inside the cell takes place by receptor-mediated endocytosis. Following the entry of the virus into the cell, several not completely understood changes take place. PRRSV has been reported to be an apoptotic-inductor virus both in vivo and in vitro. Interestingly, it has been suggested that PRRSV-induced apoptosis occurs in cells other than those in which PRRSV replicates by a bystander mechanism. In this paper the ultrastructural pathogenesis of PRRSV will be reviewed. 相似文献
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我站是重庆市农业局直属处级行政执行型全额拨款事业单位。现有技术人员43名,其中高级职称13名,中级5名,硕士11名,本科生17名,专科11名,其他4名。实验室现有面积3250m2,拥有细菌鉴定及药敏测试仪、气-质联用仪、高效液相色谱仪、气相色谱仪、电感耦合等离子体原子发射光谱仪(ICP)等199台(套)精密仪器,价值2000余万元。能承担现有国家标准、行业标准和重庆市地方标准规定的所有动物疫病诊断,饲料、兽药、畜产品质量检测检验项目。检测指标达到微量级,有的指标甚至可以检测痕量级。实验室已经全面通过重庆市质量技术监督局计量认证和农业部… 相似文献
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蜜蜂是设施农业的重要授粉昆虫,授粉蜂群的状况可能影响授粉效率的高低。通过意大利蜂(Apismellifera)对温室草莓、油桃的6次授粉重复试验,采集授粉蜂群的蜂子比值与出勤率的数据,分析蜂子比值与出勤率的相关性。结果表明,蜂子比值与工蜂出勤率之间呈显著的负相关(P<0.05),其相关系数分别为-0.8470、-0.6543、-0.7616、-0.6969、-0.6740和-0.8477,说明在正常范围内,温室授粉蜂群的出勤率随蜂子比值的减小而提高,也就是说,授粉蜂群内的子脾越好,蜜蜂出勤采集的积极性越高。 相似文献
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