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81.
An 11‐year‐old spayed female miniature dachshund was evaluated for a 2‐month history of chronic vomiting. Abdominal ultrasonography revealed a heterogeneous mass in the pyloric region. Contrast upper gastrointestinal radiography demonstrated impairment of gastric outflow. Endoscopic examination revealed multiple polyps at the gastric pylorus. The pyloric polyps were variable in size, sessile‐shaped and pedunculated. Initially, endoscopic polypectomy was attempted, but all the polyps could not be completely resected. Thus, endoscopic polypectomy with argon plasma coagulation was performed to cauterise the lesions. The histopathological diagnosis of the lesions was inflammatory polyps, and a moderate number of Helicobacter spp. was revealed. After the argon plasma coagulation treatment, the dog did not vomit, and improvement of clinical signs was maintained for 13 months. Endoscopic polypectomy with argon plasma coagulation may be useful for mixtures of sessile and pedunculated polyps. The present report may provide a basis for further studies of argon plasma coagulation treatment for canine gastrointestinal polyps.  相似文献   
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The immunomodulatory effects of beta-endorphin were studied by measurements of the production of superoxide anion, phagocytosis and chemotaxis of kidney phagocytic cells in rainbow trout, Oncorhynchus mykiss. The production of superoxide anion in phagocytic cells increased significantly in rainbow trout injected with chum salmon beta-endorphin. The responses were dose-dependent. The phagocytosis and chemotaxis also significantly increased in kidney phagocytic cells of rainbow trout injected with alpha-endorphin. These results show that beta-endorphin in rainbow trout activates the function of phagocytic cells in vivo.  相似文献   
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Adherence of four virulent and four avirulent strains of Erysipelothrix rhusiopathiae, serovar 1a, to porcine kidney cell lines, PK-15 and ESK cells, was examined in an in vitro system. The virulent strains adhered well to the cells (range of means, 9.95 +/- 0.87-36.01 +/- 1.10 per cell). In contrast, the avirulent strains showed negligible adherence to the cells (range of means, 0.11 +/- 0.04-1.41 +/- 0.13 per cell). Pretreatment of bacteria with heat, trypsin, or antiserum resulted in a marked decrease in adherence. Scanning electron microscopic examination revealed that the bacteria attached directly to the microvilli of cells.  相似文献   
87.
Inhibition of specific gene expression using RNA interference (RNAi) is a valuable tool for functional analysis of a target gene. However, there is little information available concerning RNAi for analysis of gene function in relation to the reproductive physiology of follicular cells in ruminants. Thus, the aim of this study was to evaluate the interfering effect of small interference RNA (siRNA) on expression of cyclooxygenase-2 (Cox-2) mRNA and prostagrandin F(2alpha) (PGF(2alpha)) production in bovine cumulus-granulosa (CG) cells. Bovine CG cells were collected from aspirated follicles and cultured. After reaching confluency, two experiments were conducted. In experiment 1, to investigate the effective concentration of siRNA, 0, 100, 250 and 500 pM of Cox-2 siRNA was introduced into the CG cells, respectively. After 24 h, the amount of Cox-2 mRNA expression was measured by RT-PCR and real-time PCR. In experiment 2, to investigate the time required for effective interference of siRNA and Cox-2 activity, 250 pM siRNA was introduced for 0, 3, 6, 12 and 24 h. After culture, the amount of Cox-2 mRNA expression was measured and the culture medium was collected to determine the PGF(2alpha) concentration by enzyme immunoassay. The Cox-2 mRNA expression was not affected by introduction of 100 pM siRNA into CG cells for 24 h, but 250 and 500 pM Cox-2 siRNA significantly reduced the Cox-2 mRNA expression. Moreover, the significant suppressive effect of 250 pM siRNA was observed 6 h after introduction, and the reduction of mRNA expression by RNAi became more obvious over 12 h. On the other hand, the PGF(2alpha) concentration in the culture medium was not significantly different 12 h after siRNA introduction; however, the PGF(2alpha) concentration 24 h after siRNA introduction was significantly decreased compared with the control at the same time point. These results suggest that gene silencing of Cox-2 with siRNA is capable of analyzing the function and expression of specific genes in bovine CG cells.  相似文献   
88.
Matrix metalloproteinases (MMPs) play very important roles in extracellular matrix (ECM) remodeling during ovarian follicular development, ovulation and atresia. The aim of the present study was to determine the content of gelatinases in follicular fluid in various sized bovine follicles. Bovine ovaries were collected from local slaughterhouse and follicular fluid from follicles of 2 to over 25 mm in diameter was collected. Gelatinase activity within the follicular fluid was analyzed by gelatin zymography. The concentration of inhibin in the follicular fluid was also measured by immunoblot analysis. The proMMP-2 and alpha-subunit (alphaN) inhibin was detected in all follicles regardless of their size. The abundance of proMMP-2 varied with follicular size, while alphaN inhibin increased significantly (P<0.01) in follicles of 10-14 and 15-20 mm in size. There was a positive and negative correlation between estradiol (E(2)) and progesterone (P(4)) concentrations with abundance of proMMP-2, respectively. Follicles of diameter over 25 mm had greater proMMP-9 activity than other follicles. These same follicles had significantly (P<0.01) lower inhibin levels than follicles of 10-14 and 15-20 mm in size. In conclusion, these results suggest a significant role of these proteases in growth and development of bovine follicle, particularly proMMP-2 and active MMP-2 activities in the follicular fluid could serve as markers of follicular health while abundance of proMMP-9 may possibly denote a follicular cyst.  相似文献   
89.
To improve the efficiency of transgenesis, we investigated the effects of a radical scavenger during microinjection on the development to blastocysts or pups of mouse pronuclear embryos, microinjected with the enhanced green fluorescent protein (EGFP) transgene. When embryos were microinjected in medium containing 0-1,000 units/ml catalase, the developmental rate to blastocysts was significantly higher (P<0.01) in 100-units/ml catalase (81%) than those in 0 and 1,000 units/ml (56 and 65%). To investigate the ontogenetic ability of DNA-injected embryos, EGFP-injected embryos manipulated under 0 or 100 units/ml catalase were transferred separately to recipient mice. The proportion of fetuses derived from EGFP-injected embryos manipulated under 100 units/ml catalase (29%) was significantly higher (P<0.05) than that manipulated under 0 units/ml catalase (19%). Furthermore, the numbers of transgenic pups were 17 in 100 units/ml catalase and 14 in 0 units/ml catalase. The results of the present study indicate that scavenging reactive oxygen species during in vitro micromanipulation is beneficial for the development of DNA-injected embryos.  相似文献   
90.
Medical records of dogs with colorectal polyps were retrospectively reviewed, and clinical presentation of inflammatory colorectal polyps in miniature dachshunds was evaluated. Of 33 dogs found to have colorectal polyps, miniature dachshunds were markedly over-represented with 16 dogs (48%), of which 12 (75%) were found to have inflammatory polyps. Multiple polyps localized between the rectum and the descending colon was the most common finding in miniature dachshunds with inflammatory polyps. Twenty dogs (80%) out of 25 miniature dachshunds with inflammatory colorectal polyps responded to immunosuppressive therapy using prednisolone and cyclosporine. The results of this study indicate that miniature dachshunds are predisposed to develop inflammatory colorectal multiple polyps, for which immunosuppressive therapy may be a treatment option.  相似文献   
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