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191.
The phase boundary between spinel (gamma phase) and MgSiO3 perovskite + MgO periclase in Mg2SiO4 was determined by in situ x-ray measurements by a combination of the synchrotron radiation source (SPring-8) and a large multianvil high-pressure apparatus. The boundary was determined at temperatures between 1400 degrees to 1800 degreesC, demonstrating that the postspinel phase boundary has a negative Clapeyron slope as estimated by quench experiments and thermodynamic analyses. The boundary was located at 21.1 (+/-0.2) gigapascals, at 1600 degreesC, which is approximately 2 gigapascals lower than earlier estimates based on other high-pressure studies.  相似文献   
192.

We focused on developing an epidemic prevention method for circulating masu salmon aquaculture using the probiotic Lactococcus lactis strain K-C2. This study aimed to evaluate the antibacterial activities of strain K-C2 against pathogens isolated from dead Yamame and masu salmon. First, we identified pathogenic bacteria that were isolated from dead masu salmon based on phylogenetic analysis of the 16S rRNA gene sequence and biological and biochemical characterization. The antibacterial activity of strain K-C2 against seven pathogenic strains isolated from dead masu salmon in this study and two strains of Aeromonas salmonicida previously isolated from dead Yamame was tested using a double agar plate method. The results of a BLAST search using 16S rRNA partial sequence data (1200–1300 bp) revealed that six of the former strains and one of the latter strains showed high similarity to Vibrio anguillarum and Tenacibaculum maritimum, respectively. Strain K-C2 showed antibacterial activity against all pathogenic bacteria. In this study, pathogenic bacteria were newly isolated from dead seawater-acclimated masu salmon, and strain K-C2 was found to have antibacterial effects against these pathogens.

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193.
Isolates 007Lm, S124C and Ac96I and a Vero cell-adapted Onderstepoort strain of canine distemper viruses (CDV) were examined for stability after passages in Vero cells expressing the canine signaling lymphocyte activation molecule (dogSLAM, the intrinsic receptor to CDV). These viruses passage once in Vero cells expressing dogSLAM (Vero-DST) cells (original) and after 20 passages (20p) were compared by using sequence analyses and growth characteristics. All four strains of 20p grew well and were slightly better than their originals. The 20p viruses developed a cytopathic effect slightly lower than the original strains. A few changes in amino acids in the H gene were between the 20p and the original viruses, but the sites of changes were not specific. Fragments of P, M and L genes of all strains showed no nucleotide changes after the passages. These results showed that: (1) passages of CDVs in Vero-DST cells induced amino acid changes only in the H gene, not in the P, M and L genes, unlike in a previous study with Vero cells; (2) passages did not markedly affect the growth characteristics of every viral strain. These results indicate that Vero cells expressing canine SLAM allow the isolation and passaging of CDV without major changes in viral genes.  相似文献   
194.
A solitary mass approximately 1.5 x 2 cm located on the outer side of the third digit of the left forepaw of a 7-year-old male cross-breed cat was examined pathologically. The excised tumor mass was hard and white and located within the deep dermis and subcutis. Histopathologically, the mass consisted of a mixed population of small round epithelioid cells arranged in ribbon- or cordlike structures and spindle-shaped cells forming loose irregular bundles in a mucinous stroma. The epithelioid cells were often arranged around small blood vessels. Neoplastic cells were intensely positive for vimentin and alpha smooth muscle actin and negative for keratin, desmin, S-100 protein, and neuron-specific enolase. Based on these pathologic features, the tumor was diagnosed as a glomus tumor, a neoplasm not previously reported in cats and extremely rare in animals.  相似文献   
195.
Ethionine, an analogue of methionine, induces fatty liver in rats by inhibiting protein synthesis, including that of apolipoproteins in liver. Ethionine was administered to cows to elucidate the participation in fatty liver development of impaired triglyceride secretion from liver attributable to decreased apolipoprotein synthesis. The administration resulted in a significant increase of liver triglyceride contents. Several apolipoproteins were found to have decreased concentrations. In particular, apolipoprotein B-100 in very low-density (0.95 to 1.006 g/ml) lipoprotein and in low-density (1.006 to 1.063 g/ml) lipoprotein fractions was greatly reduced. The decreases of apolipoprotein B-100 concentrations in the 2 lipoprotein fractions were at least partly correlated to the decreased triglyceride concentrations in the respective fractions. Decreased concentrations of apolipoprotein A-I in high-density (1.063 to 1.210 g/ml) lipoprotein were also observed, although not as distinctly as with apolipoprotein B-100. Total cholesterol and phospholipid concentrations in low- and high-density lipoprotein fractions were decreased. The decrease in cholesterol was attributed to reduced concentrations of cholesteryl esters. It was suggested that the impaired lipid secretion from liver attributable to the decreased apolipoprotein concentrations has a role in ethionine-induced fatty liver of cows.  相似文献   
196.
A 14-year-old intact male Maltese dog was presented with a history of pain and swelling of the left upper forelimb and lameness for 3 weeks. Hematological and radiographical examinations showed regenerative anemia and osteolysis of the humerus. Fine needle aspiration biopsy detected epithelioid- and fibroblast-like anaplastic cells with blood components. A hemorrhagic and osteolytic malignant tumor was suspected, and the affected forelimb was amputated. Histopathologically, the dog was diagnosed with primary hemangiosarcoma of the humerus. Thereafter, metastatic lesions appeared in the skin, and the dog was euthanized 1 month after the operation.  相似文献   
197.
Lymphoid neoplasms are usually diagnosed on the basis of cytological and histopathological findings. However, in some cases, discrimination of lymphoid neoplasms from reactive lymphoid proliferation is difficult. Polymerase chain reaction (PCR) amplification of the complementarity-determining region (CDR) 3 of the T-cell receptor (TCR) γ gene can be used to assess clonality of T-cell populations as a supportive diagnostic tool for T-cell neoplasms. Because the length variation in the TCRγ CDR3 is relatively small, false positive results may occur in non-neoplastic T-cell populations in the absence of high-resolution analytical methods for PCR products. In the present study, a PCR assay system was developed to detect clonal TCRγ gene rearrangement in feline lymphoid cells using GeneScan analysis. Thirty T-cell neoplasms, 27 B-cell neoplasms, and 34 non-neoplastic tissues were subjected to the newly developed TCRγ gene rearrangement analysis. Clonal TCRγ gene rearrangement was detected in 26 of 30 (87%) T-cell neoplasms, 2 of 27 (7%) B-cell neoplasms, and 1 of 34 (3%) non-neoplastic tissues. To compare GeneScan analysis with conventional PAGE and heteroduplex analysis, 20 clonal and 20 polyclonal samples were subjected to both analyses. Most of the results were concordant between the 2 analyses; however, several clonal peaks (bands) appeared as a single band when analyzed via conventional PAGE with heteroduplex analysis in 4 of the 20 (20%) clonal samples as a result of the difference in resolution. The PCR assay system to detect clonal TCRγ gene rearrangement in feline lymphoid cells, using GeneScan analysis, would be a useful molecular diagnostic tool for feline T-cell neoplasms, with high fidelity.  相似文献   
198.
Intradural disc herniation is a rarely reported cause of neurologic deficits in dogs and few published studies have described comparative imaging characteristics. The purpose of this retrospective cross sectional study was to describe clinical and imaging findings in a group of dogs with confirmed thoracolumbar intradural disc herniation. Included dogs were referred to one of four clinics, had acute mono/paraparesis or paraplegia, had low field magnetic resonance imaging (MRI) and/or computed tomographic myelography, and were diagnosed with thoracolumbar intradural disc herniation during surgery. Eight dogs met inclusion criteria. The prevalence of thoracolumbar intradural disc herniation amongst the total population of dogs that developed a thoracolumbar intervertebral disc herniation and that were treated with a surgical procedure was 0.5%. Five dogs were examined using low‐field MRI. Lesions that were suspected to be intervertebral disc herniations were observed; however, there were no specific findings indicating that the nucleus pulposus had penetrated into the subarachnoid space or into the spinal cord parenchyma. Thus, the dogs were misdiagnosed as having a conventional intervertebral disc herniation. An intradural extramedullary disc herniation (three cases) or intramedullary disc herniation (two cases) was confirmed during surgery. By using computed tomographic myelography (CTM) for the remaining three dogs, an intradural extramedullary mass surrounded by an accumulation of contrast medium was observed and confirmed during surgery. Findings from this small sample of eight dogs indicated that CTM may be more sensitive for diagnosing canine thoracolumbar intradural disc herniation than low‐field MRI.  相似文献   
199.
This retrospective study of a series of 18 cases aimed to describe the clinical and pathological findings of oral tumours in rabbits, as there have been few reports detailing spontaneous oral tumours in this species. A total of 13 different tumour types were diagnosed: squamous cell carcinoma (three), ameloblastoma (two), fibrosarcoma (two), osteosarcoma (two), cementoma (one), complex odontoma (one), giant cell epulis (one), sarcoma (one), chondrosarcoma (one), trichoepithelioma (one), papilloma (one), malignant melanoma (one) and basal cell carcinoma (one). Odontogenic tumours were relatively common in this study as compared to the oral tumours typically identified in dogs and cats. The most common clinical sign in this study was feeding abnormalities. Surgical excision and radiation therapy were found to be effective in rabbits.  相似文献   
200.
In order to understand the sorption phenomena of I on Andosols, one of the most typical soils in Japan, radiotracer experiments were carried out using I? (iodide), IO3 ? (iodate), and for comparison, Cl?(chloride) by the batch method, with special emphasis on the influence of solution pH and concentration of the respective ions. Kanuma soil composed of allophane, one of the main consistent minerals in most Andosols, was also examined regarding sorption. The sorption of I? and Cl? on Kanuma soil increased with decreasing pH and the sorptions were expressed by Henry isotherms. This indicated that these anions were electrostatically adsorbed on the positive charges which appeared on the surface of Kanuma soil. Sorption of Cl? onto Andosol could also be explained by electrostatic adsorption. Both I? and IO3 ? were readily sorbed on Andosol from water even under weakly alkaline conditions. The adsorption isotherm of IO3 ? on Andosol almost overlapped with that on Kanuma soil, suggesting that the high IO3 ? sorption on Andosol was caused by the high adsorbability of IO3 ?on allophane and/or sesquioxides of Fe and Al. However, the high I? sorption on Andosol could not be explained analogously.  相似文献   
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