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131.
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A PCR-based method was developed for the identification and detection of Phytophthora capsici in pepper plants. Three PCR primers (CAPFW, CAPRV1 and CAPRV2) specific for P. capsiciwere designed based on the sequence of its internal transcribed spacer regions. CAPFW/CAPRV1 amplify a 452 bp product from P. capsici DNA whereas CAPFW/CAPRV2 a 595 bp fragment; neither set amplifies DNA from pepper or several fungi pathogenic to pepper. In conventional (single-round) PCR, the limit of detection was 5 pg DNA for both primer sets, whereas in nested PCR the detection limit for both was of 0.5 fg. However, when the dilution series of target DNA were spiked with plant DNA, amplification declined two-fold in both conventional and nested PCR. The CAPFW/CAPRV2 set in conventional PCR was used to detect P. capsici DNA in inoculated plants. Detection occurred as soon as 8h post-inoculation in stem samples from infected but still symptomless plants. The method was also tested to detect fungal DNA in infected soils.  相似文献   
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An African Swine Fever virus (ASFV) isolated in an 1983 outbreak of the disease in Piemonte, Italy, was related by restriction endonuclease analysis of the viral genome to ASFV strains isolated in the Dominican Republic (1978), Haiti (1981) and Cameroon (1982).  相似文献   
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A monoclonal antibody was used to characterize a serogroup 1 specific Legionella pneumophila Philadelphia strain 1 antigenic determinant. A quantitative fluorometric assay was developed to quantitate the antibody sites (2.7 +/- 0.4 X 10(5)) on Legionella bacteria and to determine the physico-chemical parameters of the antibody-antigen interaction (at 4 degrees C: delta G = -10.9 Kcal X mol-1, delta H = 1.7 Kcal X mol-1, delta S = 45 cal X K-1 X mol-1). The same method was used to study the modification or the removal of the antigen by chemical and enzymatic means (trypsin, papain, lysozyme, acetone, chloroform-methanol and Tris-EDTA); only Tris-EDTA extraction resulted in a significant decrease in antibody binding sites. Inhibition studies of the fluorescein-labelled antibody binding were performed with different sugars of which only L-fucosylamine was inhibitory, and with other monoclonal antibodies to Legionella pneumophila serogroup 1 in order to compare their fine specificity and affinity. The results indicate that the epitope recognized was an immunodominant carbohydrate including an aminodideoxyhexose and carried by the lipopolysaccharide.  相似文献   
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Three mature Quarter Horse geldings were used in 2 Latin square experiments to measure the effect of cutting and vacuum cleaning of oats on digestibility. The horses were fed at the maintenance level of digestible energy (DE) as recommended by the NRC.12The data were analyzed by Latin square analysis of variance, and Tukey's t test was used to determine any differences between specific means.No significant differences among treatments were observed during either experiment, indicating that the digestibility of nutrients from oats was not affected by cutting and vacuum cleaning. Differences in the digestibility of the ether extract (EE) fraction between periods of experiment 1 were noted.  相似文献   
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