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121.
Western blotting was performed to analyze Neospora caninum tachyzoite antigens recognized by mouse IgG at different stages of infection including recrudescence. At the early stage of infection, a 36-38 kDa antigen was clearly recognized by the mouse antisera. After day 48 postinoculation, the signal of the 36-38 kDa antigen gradually weakened. Meanwhile, a 43 kDa antigen was intensely and continuously recognized from 48 to 125 days postinoculation. This 43 kDa antigen was clearly detectable with the antisera from the mice under immunosuppression. Sera from naturally infected cattle strongly reacted with the 43 kDa antigen. Therefore, the 43 kDa antigen may be useful for immunological reactions to detect infected animals except in the early stage of the infection.  相似文献   
122.
Capsule thickness of avian Pasteurella multocida type A strains was determined by transmission electron microscopy after labeling with polycationic ferritin and compared with their pathogenicity for chickens. The capsule thickness of P. multocida strains Pm-18 and X-73 was 81.4 and 50.1 nm on average, respectively. These strains were highly virulent for chicken, whereas the less virulent strains Pm-1 and Pm-3 had a thin and irregular capsule, 21.0 and 29.8 nm on average, respectively. However, the thickest capsule was observed in strain P-1059, 101.2 nm on average, and the strain revealed moderate virulence. The noncapsulated variant P-1059B, which was derived from strain P-1059, revealed low virulence. The six P. multocida strains were examined with regard to protein content on the capsule of organisms. Amounts of total proteins of crude capsular extract (CCE) from capsulated strains were approximately twice those of the noncapsulated strains. The amount of an antigenic 39 kDa protein in the CCE were found to correlate with the capsule thickness, since heavily capsulated strains exhibited the greatest amount, whereas noncapsulated strains including noncapsulated and low virulent variant P-1059B possessed little 39 kDa protein. The results demonstrated that the capsule thickness and the quantity of a 39 kDa capsular protein of avian P. multocida type A strains correlated with their pathogenicity for chickens.  相似文献   
123.
The N'-benzoyl group of N-tert-butyl-N'-benzoyl-3,5-dimethylbenzohydrazide (1) was converted to a series of benzoheterocyclecarbonyl groups in order to investigate the potential usefulness of superimposing a hydrazine insecticide on 20-hydroxyecdysone. A series of analogues with benzodioxole, benzodioxane, benzodioxapine, indole, benzoxazole, benzoxazine or benzothiazole instead of the phenyl group of (1) were synthesized and tested for their insecticidal activity against the common cutworm (Spodoptera litura F). N-tert-Butyl-N'-(3,5-dimethylbenzoyl)-1,3-benzodioxole-5-carbohydrazide and N-tert-butyl-N'-(3,5-dimethylbenzoyl)-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide showed high insecticidal activities, superior to that of (1) and equal to that of the commercial insecticide tebufenozide (RH-5992).  相似文献   
124.
A series of N'-benzoheterocyclecarbonyl-N-tert-butyl-3,5-dimethylbenzohydrazide analogues possessing a variety of substituents on the benzene rings of the benzoheterocyle moieties were synthesized and tested for their insecticidal activity. The introduction of a methyl group at the R1 position of the benzoheterocycle moiety strongly increased the insecticidal activity. Among the analogues synthesized, N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-6-chromanecarbohydrazide showed the highest insecticidal activity (LC50 = 0.89 mg litre(-1)).  相似文献   
125.
Much is known about those aspects of tuna health which can be studied in wild populations, e.g. helminth parasites. However, because aquaculture of these species is in its infancy, knowledge of microbial, nutritional and environmental diseases is limited. This review is an attempt to bring together the available information on those diseases of Thunnus spp. which cause significant morbidity, mortality or economic loss. In doing so it has become clear that much more research needs to be undertaken on the physiology of the species (southern, northern and Pacific bluefin tuna) currently used in aquaculture in order for the pathogenesis of some conditions to be properly understood. Attempts at hatchery culture of Pacific bluefin tuna has indicated that Thunnus spp. will be problematic to hatch and propagate.  相似文献   
126.
The role of a 39kDa protein of avian Pasteurella multocida in pathogenesis of fowl cholera was investigated using monoclonal antibodies (Mabs). Mabs were prepared by immunization of BALB/c mice with a crude capsular extract (CCE) of P. multocida strain P-1059 (serovar A:3). Totally eight hybridomas producing Mab were obtained. Immunoblot analysis of the hybridomas revealed that all the Mabs recognized a 39kDa protein of CCE. Treatment of CCE antigen with proteinase K or periodic acid indicated that the epitope recognized was proteinaceous. The Mabs reacted with a major 39kDa protein of CCE from encapsulated strains but not with any protein of non-capsulated strains indicating that a direct correlation between encapsulation and the 39kDa protein. Immunoelectron microscopy on strain P-1059 and the non-capsulated derivative P-1059B (serovar -:3) reacting with the Mabs and gold-labeled anti-mouse IgG indicated that the protein is associated with the capsule. The Mabs significantly inhibited the adherence of encapsulated P. multocida strains to chicken embryo fibroblast cells, but only slightly that of non-capsulated strains. Mice passively immunized with the Mabs were protected from lethal challenge with virulent strains P-1059 and X-73 (serovar A:1). Thus the capsular 39kDa protein was determined to be an adherence factor and a cross-protective antigen of avian P. multocida type A strains.  相似文献   
127.
An 8-year and 6-month-old female Maltese dog showed a stoop with rigidity of her cervix and back. Neurologic examination showed loss of proprioception, and deficiency of pain response. Postmortem examination revealed the neoplastic mass replacing the central area in the cervical spinal cord at the level from 4th to 5th segments. Histologically, the mass was composed of neoplastic ependymal cells. The neoplastic cells showed marked atypism, and occasionally formed ependymal rosettes. Based on the morphologic features, the tumor was diagnosed as anaplastic ependymoma. Immunohistochemistry showed that the neoplastic cells were negative for glial fibrillary acid protein, and slightly positive for vimentin and cytokeratin.  相似文献   
128.
A case of olfactory neuroepithelioma was investigated electron microscopically and immunohistochemically. The tumor mass was found in the nasal cavities of a 10-year-old female dog, which showed epistaxis, nasal discharge and facial swelling. The tumor tissue consisted of tubular structure of cuboidal to columnar cells and compactly arranged nests of small cells surrounded by a fibrovascular stroma. Mitotic figures were frequently observed. Immunohistochemically, the tumor cells frequently showed positive for neurofilament protein, synaptophysin and/or carnosine in addition to keratin. Ultrastructurally, tight junction was observed between the tumor cells. No dense-cored secretory granules were shown in the tumor cells. These findings indicated that the present tumor had neuronal and epithelial features probably originating from the olfactory epithelium.  相似文献   
129.
130.
Recently, glyphosate‐resistant Italian ryegrass (Lolium multiflorum Lam.) was found on rice paddy levees in a western region of Shizuoka Prefecture, Japan. Naturalized populations of Italian ryegrass are frequently infected with fungal Epichloë endophytes. Endophytes often confer benefits to their host grasses. This study investigated the influence of five weed management treatments on glyphosate resistance and endophyte infection in Italian ryegrass that was growing on paddy levees where glyphosate‐resistant individuals were dominant. The weed management treatments were: (i) mowing once before the grass flowered; (ii) mowing once during flowering; (iii) mowing twice during flowering; (iv) glyphosate application before flowering; and (v) no treatment. The seeds were collected from the treatment plots in 2013 and 2014. The seeds were examined for endophyte infection and the seedlings that had been grown from the seeds were tested for the frequency of glyphosate resistance. The seedlings that had been derived from the glyphosate treatment showed higher frequencies of glyphosate resistance than those seedlings that had been derived from all the other treatments. Endophytes were found in all populations of the seeds from the paddy levees, with higher infection rates in the seeds that had been derived from the glyphosate treatment and the twice‐mowed treatment. There was a significant relationship between the endophyte infection frequency in the seeds and glyphosate resistance in the seedlings that had been grown from the same populations. The results indicate that where glyphosate herbicides are frequently used, selection for glyphosate‐resistant Italian ryegrass occurs, and along with this, the frequency of endophyte infection also increases.  相似文献   
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