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81.
82.
We investigated the effect of oxidative stress induced by hydrogen peroxide (H2O2) on lipid peroxide (LPO) level and nuclear maturation in porcine oocytes cultured with or without cumulus cells. After 22 h of pre‐culture, oocytes with attached cumulus cells (COC group) or denuded oocytes (DO group) were cultured with H2O2, and intra‐oocyte H2O2 and LPO levels were quantitatively analyzed using immunofluorescence. This is the first report evaluating LPO levels in porcine oocytes. After H2O2 supplementation, the DO group showed severe accumulation of H2O2 and LPO in the oocytes. Similarly, while inhibition of progression of nuclear maturation was observed in both groups, the effect was more severe in the DO group. These results demonstrate that cumulus cells reduce the accumulation of H2O2 stress in oocytes. Furthermore, we attempted to reduce the oxidative stress by H2O2 with L‐carnitine, a H2O2 scavenger. L‐carnitine decreased H2O2 and LPO levels in the oocytes in both groups, and improvement in the progression of impaired nuclear maturation was observed. These effects were different by the presence of cumulus cells. Our results provide that L‐carnitine is useful for alleviating H2O2‐induced oxidative stress by reducing LPO levels and improving the progression of nuclear maturation.  相似文献   
83.
Spontaneous malignant mesothelioma was found in a 104-week-old male Crj:CD(SD) rat. The tumor was scattered on the surface of the lung, heart, mediastinal pleura and thoracic wall and metastasized to the alveolar septa. Histopathologically, small flattened or cuboidal tumor cells proliferated with stroma, formed almost normal papillary structures and reacted positively to colloidal iron stain and immunohistochemical staining for mesothelin. Round hyalinous stromata were pronounced, which is a characteristic feature, and the possible reason for this is as follows; at first, a small amount of collagen fibers was formed in the center of the clusters of several tumor cells, and then the cell clusters expanded like balloons with an increase in the collagen fibers.  相似文献   
84.
85.
To demonstrate the psychophysical effect of edge-grain patterns on visual impressions received by human observers, printed images of the edge-grain patterns of 16 species were prepared as well-regulated visual stimuli, and impressions of the patterns on 32 subjects were evaluated using six categories. Image characteristics of the patterns were expressed numerically using contrast values that were derived by multi-resolution contrast analysis (MRCA) proposed by the authors, and relationships between the image characteristics and the visual impressions were examined. The difference in lightness between local areas with a certain size in the image was used as the contrast value, which could be used to detect the change in lightness due to the particular feature in the edge-grain pattern. While some impressions were almost independent of the contrast values, other impressions showed highly positive or negative linear relationships to the contrast values, derived at the optimal filter size in MRCA. Moreover, these optimal sizes were rarely affected by color information. The contrast value proposed in this paper would be a good numerical index that could be used not only to describe image characteristics of the edge-grain patterns but also to estimate some of their visual impressions.  相似文献   
86.
Spontaneous mammary adenocarcinoma was observed in a 12-week-old female SD rat. A movable mass in the right cervical region was found at 11 weeks of age, and the rat was sacrificed the following week. The mass was located in the vicinity of the right salivary gland and measured 38 mm × 26 mm × 16 mm in gross size. It was a firm whitish mass, with a cut surface that was also whitish in appearance. Histopathologically, neoplastic cells formed glandular structures that contained secreted eosinophilic material. Ultrastructurally, similar secreted material and lipid droplets were in the cytoplasm of the neoplastic cells. Immunohistochemically, the neoplastic cells were positive for cytokeratin 8, cytokeratin 18 and estrogen receptor α. Based on these findings, the tumor was diagnosed as a mammary gland adenocarcinoma, and we therefore conclude that this tumor type can occur spontaneously in female SD rats as young as 12 weeks of age.  相似文献   
87.
This study evaluated the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) analysis of fliC for typing flagella antigen (H) of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) strains isolated from different animals. The molecular typing of the H type was efficient in the determination of 93 (85%) strains. Two nonmotile (H-) E. coli strains showed a PCR-RFLP electrophoretic profile that did not match known H type patterns. The fliC nucleotide sequence of strains B2N and 4a revealed a nucleotide substitution at the restriction site and a nucleotide insertion that generated a stop codon, respectively. The results of this study showed that PCR-RFLP analysis of fliC is faster, less laborious and as efficient for the determination of H type E. coli isolated from animals, compared to serotyping and that it is useful in determining H type in nonmotile strains and strains expressing non-reactive H antigens. Moreover, the fliC sequence of strain B2N suggests that we could have found a new flagellin antigen type.  相似文献   
88.
To determine the acute effects of carvedilol (beta-blocker) on cardiovascular and renal function and its pharmacokinetics in dogs. Fifteen mature mongrel dogs (7-15 kg) of both sexes were used in these experiments. Eight dogs served as controls, and seven dogs served as iatrogenic mitral regurgitation (MR) experimental animals. Carvedilol (0.2, 0.4, and 0.8 mg/kg, P.O.) was administered, and the blood carvedilol concentration was analyzed by reverse-phase high-performance liquid chromatography. The response to isoproterenol or phenylephrine was also evaluated. Isoproterenol (0.025 microg/kg/min) was infused via the saphenous vein for 5 min, and phenylephrine (5 microg/kg) was injected with carvedilol (0.2, 0.4 mg/kg) or placebo for 4 days. The heart rate and arterial blood pressure were measured, and LV fractional shortening was measured by echocardiography. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured by intravenous infusion of sodium thiosulfate and sodium para-aminohippurate. Carvedilol (0.2 mg/kg) decreased the heart rate, whereas renal function, arterial blood pressure, and left ventricular contractile function were not affected. Carvedilol (0.4 mg/kg) decreased heart rate, blood pressure, and renal function. The tachycardic response to isoproterenol was significantly diminished for 36 hr by 0.4 mg/kg carvedilol. Carvedilol 0.2 mg/kg inhibited this effect for 24 hr. Thus, it is necessary to titrate the dosage of carvedilol, it should be initiated at less than 0.2 mg/kg and titrated up to 0.4 mg/kg for heart failure dogs.  相似文献   
89.
This report describes the pathological characterizations of a rare case of necrosis of the femoral head that was spontaneous, bilateral, avascular and nontraumatic. A 14-month-old beagle dog was presented with pain in the hind limbs. At necropsy, the articular surface in the bilateral femoral head was markedly irregular. There were no gross abnormalities other than in the hip joints. Microscopically, a wide range of trabecular bone necrosis localized in the subchondral area was observed in both femoral heads. In the right femoral head, fibrosis and proliferative vessels were noted in the subchondral area. The articular cartilage was thickened irregularly, but there was no evidence of cartilage necrosis. The bone marrow adjacent to the affected area showed severe depression. In the metaphysis, atrophic bone marrow, but not bone necrosis, was observed. This was a rare case of spontaneous necrosis of the femoral head in an experimental beagle dog.  相似文献   
90.
The objective of this study was to evaluate the hemodynamics of the anesthetic isoflurane in healthy cats given angiotensin-converting enzyme inhibitor (ACEI). The 7 healthy young cats and 3 old cats were received placebo or enalapril 0.5 mg/kg orally. The change in systolic arterial pressure from the baseline to 30 min postanesthesia in the ACEI group was significantly higher than in the placebo group (mean +/- SD: -39 +/- 13% vs. -17 +/- 12%, respectively). The present study indicated that general anesthesia may induce hypotension after the administration of an ACEI.  相似文献   
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