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1.
To detect serum antibody against Pasteurella multocida (P. multocida) in infected rabbits. a modified immunoperoxidase assay was applied. An outbreak of P. multocida infection in rabbits started from sudden death. The infected rabbits had severe fibrinous and purulent pneumonia with hemorrhage, and a large number of P. multocida (A:12) was isolated from the trachea and lungs of the animals. Antibodies of IgM and IgG to P. multocida were assessed by immunohistochemical staining using the sera of the animals as primary antibodies and applying them to formalin-fixed, paraffin-embedded sections of P. multocida attached to calf fibrin. IgM antibodies to P. multocida were first detected 7 days after the onset of the disease. IgG antibodies began to rise on the 7th or 14th day. These results suggested that the modified immunoperoxidase assay could detect antibodies against P. multocida.  相似文献   
2.
Two feline cases were diagnosed as systemic cryptococcosis due to Cryptococcus neoformans (teleomorph: Filobasidiella neoformans) by PCR assay with CAP59 gene primers using urine, serum and biopsy samples. The results of molecular analysis were consistent with the mycological findings.  相似文献   
3.
Canine necrotizing meningoencephalitis (NME) and granulomatous meningoencephalomyelitis (GME) were compared pathologically. Gross observation exhibited lateral ventricular dilation and discoloration, malacia and/or cavitation of the cerebrum in NME. On the contrary, gross changes were milder in GME, except for occasional visible granulomatous mass formation. Histopathologically, the lesions of NME were distributed predominantly in the cerebral cortex and various degrees of inflammatory and necrotic changes were observed according to clinical stages. Besides, microscopic lesions of GME were mainly distributed in the white matter of the cerebrum, cerebellum and brainstem, which are characterized by perivascular cuffing, multiple granulomas and leptomeningeal infiltrates. Although macrophages and lymphocytes were predominant in the inflammatory lesions of both disorders, macrophages in GME transformed into epithelioid cells and exhibited more massive infiltration. Although lectin RCA-1-reactive cells were numerous in both disorders, lysozyme immunoreactive cells in NME were fewer than that in GME. Parenchymal infiltration of MAC387-positive cells was common in GME and limited in NME. The number of CD3-positive lymphocytes in the GME lesions tended to be greater than in NME, though the difference was not statistically significant. Morphological and immunohistochemical differences of the lesions, in particular, the characteristics of infiltrative macrophages may reflect these different pathogeneses of the two disorders.  相似文献   
4.
A new canine cell line, named CCT, was established from the cutaneous malignant histiocytosis in a 4-year-old male Borzoi. CCT proliferated with loose adherence and doubling time was approximately 30 hr. When co-cultured with latex beads, CCT phagocytized beads vigorously. Lysozyme and vimentin were positive by immunostaining, and non-specific esterase and acid phosphatase were positive by cytochemical staining. These features indicated the cells had a histiocytic nature. Furthermore, by subcutaneous injection to nude mice CCT could successfully form tumors with the morphological and immunohistochemical features similar to the original tumor.  相似文献   
5.
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species.  相似文献   
6.
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA.  相似文献   
7.
The effect of soil freeze–thaw cycles on the denitrification potential was examined based on the C2H2 inhibition method. The gross N2O production curve of the soil sample (incubation with C2H2) showed minor changes between the freeze–thaw treatment and the unfrozen control. However, kinetics analysis revealed that the initial production rate, an indicator of the population density of denitrifying communities, decreased (P = 0.043) and the specific growth rate constant, an indicator of the activity of denitrifying communities, increased (P = 0.039) as a result of the freeze–thaw cycles in five of six soil samples examined. The increase in the specific growth rate constant suggested the stimulation of the activity of denitrifying communities that survived after the freeze–thaw cycles and may explain the minor suppression on the gross N2O production in spite of decreasing the population density of denitrifying communities that was suggested by the initial production rate. The net N2O production curve of the soil sample (incubation without C2H2) showed a remarkable change in one out of six soil samples, and in that one soil sample, N2O release to the atmosphere was largely stimulated (7.6 times) by the freeze–thaw cycles. However, the stimulation of the N2O release by the freeze–thaw cycles was even observed in two other selected soil samples (4.6 and 1.8 times), suggesting that an imbalance in the N2O-producing and N2O-reducing activities of denitrifying communities might complementally explain the N2O release stimulated by the freeze–thaw cycles.  相似文献   
8.
The interface between decaying plant residues and soil is a hotspot for microbial immobilization of soil inorganic N. Recent studies on forest and grassland soils have demonstrated that rapid abiotic immobilization of inorganic N is also induced by the presence of plant residues. We, therefore, examined (1) how N immobilization varies with distance from the soil-residue interface and (2) whether abiotic immobilization occurs in agricultural soils. Spatiotemporal changes of N immobilization in the soil-residue interface were evaluated using a box that enabled soil to be sampled in 2 mm increments from a 4 mm-thick residue compartment (RC). The RC was filled with paddy soil containing ground plant residue (rice bran, rice straw or beech leaves) uniformly at a rate of 50 g dry matter kg−1. Soil in the surrounding compartments contained no residue. After aerobic incubation for 5, 15 and 30 days at 25 °C, soils in each compartment were analyzed. After 5 days, significant depletion of inorganic N occurred throughout a volume of soil extending at least 10 mm from the RC in all residue treatments, suggesting extensive diffusion of inorganic N towards the RC. The depletion within 10 mm of the RC amounted to 5.0, 4.3 and 3.4 mg for rice bran, rice straw and beech leaf treatment, respectively. On the other hand, microbial N had increased significantly in the RC of the rice bran and rice straw treatments (11 mg and 5.5 mg, respectively) and insignificantly in the RC of the beech leaf treatment (0.06 mg). This increase amounted to 221% (rice bran), 129% (rice straw) and 1.7% (beech leaves) of the decrease in inorganic N within 10 mm of each RC. Thereafter the rate of N mineralization exceeded that of immobilization, and inorganic N levels had recovered almost to their original level by 15 days (rice bran) and 30 days (rice straw and beech leaves). These results suggested the predominance of biotic immobilization in soil near rice bran and rice straw and of abiotic immobilization in soil near beech leaves. No significant increase in both microbial and soluble organic N in the vicinity of beech leaves after incubation for 5 days further suggested that the abiotic process was responsible for the transformation of inorganic N into the insoluble organic N.  相似文献   
9.
KIT, a transmembrane receptor tyrosine kinase, is one of the specific targets for anti-cancer therapy. In humans, its expression and mutations have been identified in malignant melanomas and therapies using molecular-targeted agents have been promising in these tumours. As human malignant melanoma, canine malignant melanoma is a fatal disease with metastases and the poor response has been observed with all standard protocols. In our study, KIT expression and exon 11 mutations in dogs with histologically confirmed malignant oral melanomas were evaluated. Although 20 of 39 cases were positive for KIT protein, there was no significant difference between KIT expression and overall survival. Moreover, polymerase chain reaction amplification and sequencing of KIT exon 11 in 17 samples did not detect any mutations and proved disappointing. For several reasons, however, KIT expression and mutations of various exons including exon 11 should be investigated in more cases.  相似文献   
10.
Adrenal medullary cells are derived from the neural crest. To study the formation process of the adrenal medulla in the embryonic period, we visualized chromaffin cells of rat embryos at 13 to 17 days of gestation using anti-tyrosine hydroxylase (TH) antiserum, and created three-dimensional images from serial tissue sections. Between 13 and 15 days of gestation, TH-positive cells (chromaffin cells) migrated from a group of TH-positive cells present dorsal to the adrenal primordium via the medial cranial end of the adrenal primordium into the adrenal primordium. At or after 16 days of gestation, the adrenal capsule was formed except on the ventral aspect of the cranial end of the adrenal gland, from which TH-positive cells penetrated into the adrenal gland. The reconstructed images showed that TH-positive cells were present contiguously from the sympathetic chain ganglia through a group of TH-positive cells ventral to the adrenal gland into the adrenal cortex, and that the group of TH-positive cells ventral to the adrenal gland communicated with the preaortic ganglion present ventral and caudal to the adrenal gland. These results suggest that neural crest cells use the same pathway to migrate to the sympathetic chain ganglia dorsal to the adrenal gland, to the adrenal gland, and to the preaortic ganglion.  相似文献   
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