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101.
The fate of spherosome on the degradation of tetrachloroethylene in soil was investigated for 38 days. The time needed to become the half value of the initial concentration is 8 days for the case with spherosome and 15 days for the case without spherosome. The time needed for complete degradation is 25 days for the case with spherosome and 38 days for the case without spherosome. The degradation of tetrachloroethylene appeared to be essentially due to the biological activity of the soil. Spherosome should enhance the rate of tetrachloroethylene destruction.  相似文献   
102.
We investigated the distribution of 3 types of steroidogenic enzymes, P450scc, 3betaHSD, and P450c17, in wild raccoon dog ovaries by immunohistochemistry. Six pairs of ovaries were obtained from wild raccoon dogs between 2001 and 2003, with 3 of the 6 pairs of ovaries containing corpora lutea. P450scc, 3betaHSD, and P450c17 were localized in the granulosa and theca cells of these raccoon dogs. Furthermore, lutein cells were stained positively for P450scc and 3betaHSD in the pregnant and non-pregnant raccoon dogs. These results suggest that granulosa and theca cells may synthesize progesterone and androgens, which may play an important role in follicular development, and that lutein cells are a major source of progesterone in wild raccoon dogs.  相似文献   
103.
The purpose of this study was to ascertain whether or not Japanese black bears (Ursus thibetanus japonicus) are induced ovulators. The progesterone levels of female bears kept with a male and allowed to mate (n=2) and female bears allowed contact with a male through bars but not allowed to mate (n=6) during the mating season increased significantly in late October. Based on this result, the female bears were considered to have ovulated. Females isolated from males (n=3) were ovarioectomized after the mating season, and no corpora lutea were observed, indicating they had not ovulated. These findings suggest that Japanese black bears may be induced ovulators that ovulate with stimuli from males and without coitus at a high rate.  相似文献   
104.
The rabbit is considered to be a valuable laboratory animal. We compared glycerol, lactamide, acetamide, and dimethylsulfoxide (DMSO) as cryoprotectants in egg-yolk diluent of ejaculated Japanese white rabbit spermatozoa for improvement of sperm cryopreservation methods. Rabbit semen was frozen with 1.0 M glycerol, lactamide, acetamide, or DMSO in plastic straws. Forward progressive motility and plasma membrane integrity of the post-thaw spermatozoa were examined. The rate of forward progressive motile spermatozoa in lactamide (37.8 +/- 3.0%) was significantly (P<0.05) higher than in glycerol (17.0 +/- 3.3%). In addition, the rates of sperm plasma membrane integrity in lactamide and acetamide (35.9 +/- 3.3% and 30.2 +/- 3.0%, respectively) were significantly (P<0.05) higher than in glycerol (17.0 +/- 2.6%). The results indicate that 1.0 M lactamide and acetamide have higher cryoprotective effects than 1.0 M glycerol for cryopreservation of Japanese white rabbit spermatozoa.  相似文献   
105.
Although some clinical studies have suggested that spironolactone (SPL), a mineralocorticoid receptor (MR) antagonist, appears to increase the blood glucose levels, experimental studies have not supported this notion. Here, we investigated the effect of SPL on blood glucose levels in SHR/NDmcr-cp(cp/cp) (ND) rats, an animal model of metabolic syndrome, in comparison with that of eplerenone (EPL), another MR antagonist. At the same dose of 100 mg/kg, SPL and EPL increased the urinary sodium-to-potassium ratio to a comparable extent, indicating that both agents have similar renal MR antagonistic efficacy in ND rats. Interestingly, SPL but not EPL significantly increased the level of blood glucose. The oral glucose tolerance test revealed that treatment with SPL led to glucose intolerance. The levels of serum insulin and adiponectin, regulators of the blood glucose level, were virtually unaffected by treatment with SPL. On the other hand, SPL induced a marked increase in the blood level of aldosterone, known to be a risk factor for insulin resistance. These results demonstrate that in comparison with EPL, SPL characteristically impairs glucose tolerance in an animal model of metabolic syndrome, in association with a higher blood level of aldosterone.  相似文献   
106.
107.
A total of 518 fecal samples collected from 183 apparently healthy cattle, 180 pigs and 155 broilers throughout Japan in 1999 were examined to determine the prevalence and antimicrobial susceptibility of Salmonella. The isolation rates were 36.1% in broilers, 2.8% in pigs and 0.5% in cattle. S. enterica Infantis was the most frequent isolate, found in 22.6% of broiler fecal samples. Higher resistance rates were observed against oxytetracycline (82.0%), dihydrostreptomycin (77.9%), kanamycin (41.0%) and trimethoprim (35.2%). Resistance rates to ampicillin, ceftiofur, bicozamycin, chloramphenicol and nalidixic acid were <10%. CTX-M-2 β-lactamase producing S. enterica Senftenberg was found in the isolates obtained from one broiler fecal sample. This is the first report of cephalosporin-resistant Salmonella directly isolated from food animal in Japan.  相似文献   
108.
109.
A dog with purulent vulval discharge was found to have many cysts containing purulent mucus in the uterine cervix. The uterine horns did not contain any pus. Histological examination revealed a cervical adenomyosis infiltrated by many neutrophils. After an ovariohysterectomy including the whole cervix, the dog recovered well.  相似文献   
110.
Leukotoxin family genes in Staphylococcus aureus isolated from domestic animals were examined by polymerase chain reaction. LukS and lukF genes were detected in all 48 avian and 72 porcine isolates of S. aureus. LukE and lukD genes, located in a putative staphylococcal pathogenicity island (Sapln3/Saplm3), were recognized in 44 (91.7%) of 48 avian isolates, but these genes were not detected in porcine isolates. In 297 bovine isolates collected from mastitic cow's milk and bulk milk from dairy farms in two regions, lukM and lukF-PV(P83) genes in addition to lukS-lukF and lukE-lukD genes were detected in 100 (62.5%) of the 160 isolates from Ishikawa and in118 (86.1%) of the 137 isolates from Hokkaido. When the lysogeny of S. aureus bovine isolates was examined by treatment with mitomycin C, clearing of the culture due to cell lysis was observed in 34 (91.9%) of 37 lukM-lukF-PV(P83) genes--positive isolates. In addition, we isolated a novel lukM-lukF-PV(P83)-carrying (designated phiLukM), and revealed that the lukM-lukF-PV(P83) genes were located very close to an amidase gene on the temperate phage genomes. These results suggest horizontal transmission of lukM-lukF-PV(P83) genes by temperate bacteriophages in S. aureus of bovine origin.  相似文献   
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