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1.
Biopsies of skin from a 2-year-old heifer with spontaneously regressing dermal leukosis were examined. The heifer was not infected with bovine leukemia virus and was negative for tumor-associated antigens of enzootic bovine lymphosarcoma. By hematological standards for bovine leukemia, the heifer was positive at about 60 days post-occurrence of the disease (POD). At 53 days POD, lymphoblastic neoplastic cells in the dermis reacted with anti-T lymphocyte monoclonal antibody by the avidin biotin peroxidase complex method. The cells had intracytoplasmic clustered dense bodies under electron microscopy. From 53 to 83 days POD, figures of the transepithelial elimination (TE) against neoplastic cells and perivascular infiltration of small lymphocytes were in the dermis. Small lymphocytes reacted with anti-T lymphocyte monoclonal antibody. At necropsy there were no neoplastic lesions; there were flat lymph node-like tissues in the subcutis. Many germinal centers were seen in the lymphatic organs. Blood lymphocytes at 46 days POD were stimulated by phytohemagglutinin-P and concanavalin A. Sera, taken until 75 days POD and at necropsy, showed an inhibitory effect on mitogen-induced blastogenesis of normal bovine lymphocytes. These results suggested the existence of a spontaneous regressive mechanism against neoplastic lesions by TE and tumor immunity.  相似文献   
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Porcine bioprosthetic valves cross-linked with glutaraldehyde and polyepoxy compound were newly developed for mitral valve replacement (MVR) in dogs. Five beagle dogs were performed a left thoracotomy and underwent MVR using the porcine bioprosthetic valves during cardiopulmonary bypass (CPB). A vein catheter inserted into right atrium and a vent catheter inserted into the right ventricle to drain. The hemodynamic conditions of CPB were excellent during surgery. The left atrial pressure was measured before and after MVR; there was no significant difference and it was normal. Thrombosis and the prosthetic valve regurgitation were not observed one week after MVR. Pressure half time (PHT) prolonged significantly (P<0.05) from 31.40 +/- 4.0 msec presurgery to 99.20 +/- 19.4 msec at seven days after MVR, although it indicated the normal range as the bioprosthetic valve. The symptom of the prosthetic valve failure was not observed. This study indicated that the MVR using porcine bioprosthetic valves under CPB might have been effective in dogs as a short-term evaluation.  相似文献   
4.
We succeeded to establish cell lines from endemic fish species Honmoroko Gnathopogon caerulescens, which inhabits Lake Biwa, the third oldest lake in the world. Two cell lines designated as RMT1 and RMO1 were established from testis and ovary of G. caerulescens, respectively. These cell lines were initially cultured in Leibovitz’s L-15 medium supplemented with fetal bovine serum (FBS), fish embryo extract, epidermal growth factor, and basic fibroblast growth factor. Further addition of forskolin and β-mercaptoethanol was required to establish and maintain these cell lines for more than 60 passages. RMT1 and RMO1 cells showed fibroblast- and epithelial-like morphology, respectively. From immunocytochemical staining and gene expression patterns, RMT1 cells showed a characteristic of testicular Sertoli cells and RMO1 cells did that of ovarian theca cells. Both RMT1 and RMO1 cells multiplied well in the medium supplemented with 10 % FBS at 28 °C and their minimum population doubling times were 24.4 and 28.8 h, respectively. At the 45th passage, most of the RMT1 and RMO1 cells had a hyperploid set of chromosomes (67.3 and 96.1 %, respectively). Cells with normal diploid chromosome set were not observed. RMT1 cells were transfected with an enhanced green fluorescent protein (EGFP) expression vector and human elongation factor 1 α promoter worked efficiently to express EGFP. In addition, EGFP-expressing cell lines were also established, suggesting that the cell lines could be utilized as an in vitro monitor system (biosensor) for the evaluation of endocrine disruptors which might affect gonadal function.  相似文献   
5.
Global warming is now attracting the world attention. Methane is an important greenhouse gas next to CO2. Prather et al. (1995) estimated that rice paddy fields account for 14% of all biogenic atmospheric methane. It is considered that methane production from rice paddy fields is increasing along with the increase of the population. Therefore, the development of rice cultivation techniques for reducing methane production is essential, in order to preserve the global environment.  相似文献   
6.
The effects of B and Ca treatments on root growth, nutrient localization and cell wall properties in wheat ( Triticum aestivum L.) plants with and without Al stress were investigated. Seedlings were grown hydroponically in a complete nutrient solution for 7 d and then treated with B (0, 40 μM), Ca (0, 2,500 μM), and Al (0, 100 μM) in a 500 μM CaCl2 solution for 8 d. The cell wall materials (CWM) were extracted with a phenol: acetic acid: water (2:1:1 w/v/v) solution and used for subsequent pectin extraction with trans -1,2-diami-nocyclohexane- N,N,N,N -tetraacetic acid (CDTA) and Na2CO3 solutions. Boron, Ca, and B + Ca treatments enhanced root growth by 19.5, 15.2, and 27.2%, respectively, compared to the control (pH 4.5). Calcium and B+Ca treatments enhanced root growth with Al stress by 43 and 54%, respectively, while B did not exert any effect. The amounts of CWM and pectin per unit of root fresh weight increased by Al treatment, whereas the Ca and B+Ca treatments slightly reduced the contents of these components. Seventy-four percent of total B, 69% of total Ca, and 85% of total Al were located in the cell wall in the B, Ca, and Al treatments, respectively and 32% of total B, 33% of total Ca, and 33% of total Al were located in the CDTA-soluble and Na2CO3-soluble pectin fractions. A more conspicuous localization of B was observed in the presence of Al. Aluminum treatment markedly decreased the Ca content in the cell wall as well as pectin fractions, mainly in the case of the CDTA-soluble pectin fraction. Boron + Ca treatment decreased the Al content in the cell wall and pectin fractions compared to the Ca treatment alone in the presence of Al. It is concluded that the B+Ca treatment enhanced root growth and, B and Ca uptake, and helped to maintain a normal B and Ca metabolism in the cell walls even in the presence of Al.  相似文献   
7.
In order to examine the antigenic similarity and specificity of the trail antigen of Eimeria stiedai and Etp 100, a microneme protein of Eimeria tenella, monoclonal antibodies to the trail antigen of E. stiedai sporozoites were selected by an indirect immunofluorescent antibody method. The monoclonal antibody of one clone, 3D10, reacted with the anterior portion of non-fixed sporozoites. By immunoblotting, the monoclonal antibody was found to react with a 100 kDa antigen of E. stiedai sporozoites, and a 117 kDa antigen of E. tenella sporozoites and merozoites. It was also found to react with a recombinant protein with thrombospondin-/properdin-like motifs homologous to E. tenella microneme protein Etp 100. The monoclonal antibody significantly inhibited the penetration of E. stiedai sporozoites into cultured rabbit hepatobiliary epithelial cells. These results suggest that E. stiedai sporozoites have a trail antigen, located in the anterior region on the outer surface of the sporozoites, which has an epitope with thrombospondin-/properdin-like motifs similar to E. tenella microneme protein Etp 100. This protein may play an important functional role in the process of penetration of host cells.  相似文献   
8.
In the present study, the daily excretion of potassium (K) in urine (urinary K(UK)) was estimated from a 6 h urine sample using urinary creatinine (UC) as the index substance. All urine was collected from six pregnant Holstein cows at 6 h intervals for 24 h on 3 days of the 4th, 2nd and final week before the expected date of parturition. In total, 72 6 h urine samples were obtained. Daily UC excretion (mg/day per kg bodyweight (BW)) was almost the same for the three sampling days. Daily UC excretion varied among cows from 22.1 to 24.3 mg/day per kg BW with a mean of 22.8 mg/day per kg BW with no significant difference. Thus, daily UC excretion was confirmed to be constant throughout the prepartum period with no differences among individuals. The concentration ratios of K to creatinine ((UK mg/dL)/(UC mg/dL) (UK/UC)) correlated strongly to the hourly K excretions (mg/h per kg BW) (r = 0.952, P < 0.01) in the 6 h urine samples. The differences in the UK/UC ratio between sampling periods were not significant within each cow. Therefore, daily UK excretion (mg/day) can be estimated using the equation: daily UK excretion (mg/day) = daily UC excretion (mg/day per kg BW) × BW (kg) × 6 h urine sample UK/UC, where daily UC excretion can be a given value.  相似文献   
9.
The goal of the current study was to compare the efficiency of gas exchange and platelet conservation of a new extracapillary blood flow oxygenator versus an endocapillary blood flow oxygenator during open heart surgery with extracorporeal circulation in dogs. Dilation and remodeling of the right ventricular outflow tract of dogs was performed using a patch graft technique to simulate pulmonary stenosis. Sequential pre- and post-operative blood analysis revealed that gas exchange efficiency and platelet conservation was significantly greater with the extracapillary blood flow oxygenator than with the endocapillary blood flow oxygenator. However, the priming volume of the extracapillary blood flow oxygenator was significantly greater, leading to hemodilution. We conclude that while the extracapillary blood flow oxygenator provided benefits in terms of gas exchange and platelet conservation, development of a smaller extracapillary blood flow type oxygenator to reduce hemodilution effects would be beneficial.  相似文献   
10.
PCR amplification and nucleotide sequencing of the mini-exon gene revealed that four strains isolated from a sloth (Choloepus hoffmanni), a squirrel (Sciurus granatensis) and two sandflies (Lutzomyia hartmanni) in Ecuador were indistinguishable from Endotrypanum monterogeii. Another strain isolated from Lu. hartmanni showed the high sequence similarity to E. schaudinni. Since three of these strains have been previously identified as Leishmania (Viannia) equatorensis, the results demonstrate that L. (V.) equatorensis is genetically closely related to the genus Endotrypanum. The present study also indicates that Endotrypanum species are distributed in arboreal animals and sandflies in Ecuador, and that mini-exon gene amplification is useful for epidemiological studies of Leishmania and Endotrypanum in the New World.  相似文献   
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