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131.
Slow-reacting complement-requiring neutralizing (NT) antibody was detected in sera from cattle 2 weeks after infection with Akabane virus. Bovine sera obtained 3 or 4 weeks after infection contained slow-reacting noncomplement-requiring NT antibody. The slow-reacting complement-requiring NT antibody was sensitive to 2-mercaptoethanol (2-ME), whereas the slow-reacting noncomplement-requiring NT antibody was resistant to 2-ME. The initial phase may represent the IgM response and the later phase a change to IgG. A NT test was developed in which virus-serum mixtures were incubated at 4 degrees C for 48 h and then with complement at 37 degrees C for 60 min; this gave an improved sensitivity over the previous incubation at 37 degrees C for 60 min. 相似文献
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Typing of R factors by genetic properties was done with Salmonella typhimurium and Escherichia coli isolated from calves on a feedlot where epizootics of clinical or subclinical calf salmonellosis had repeatedly occurred during 5 years. Forty-nine R factors from S typhimurium were fi- (no fertility inhibition) and spp- (no restriction against phage lambda vir). Twenty-three (46.9%) of them belonged to compatibility group Ialpha and the remainder were nontypable. Fourteen R factors from E coli belonged to different genetic types: fi+ (11=78.6%) and fi- (3=21.4%); spp+ (1=7.1%) and spp- (13=92.9%); compatibility groups FII (5=35.7%), N (1=7.1%), and nontypable (8=57.2%). In contrast to the R factors of S typhimurium, 9 (64.3%) of the 14 R factors of E coli carried resistance against aminobenzyl penicillin with or without kanamycin resistance. The compatibility groups of R factors of S typhimurium seemed to be useful as a subsidiary epizootiologic marker in this feedlot. 相似文献
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Sato T Miyoshi T Shibuya H Fujikura J Koie H Miyazaki Y 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2005,52(1):22-25
A 10-year-old German shepherd dog was presented with a severe abdominal distension. At necropsy, whitish and firm mass was observed in the mesentery with metastases in the pericardium and pleura. The intestinal serosa was thickened and stiff. Histologically, the tumours were composed of a biphasic population of cells, which reacted with cytokeratin, vimentin and Wilms' tumour 1 protein antibody. Ultrastructural examination revealed numerous microvilli, abundant rough endoplasmic reticulum, numerous desmosomes and bundles of microfilament. The tumour was classified as biphasic mesothelioma of peritoneal origin. 相似文献
137.
Sato H Miura R Kai C 《Comparative immunology, microbiology and infectious diseases》2005,28(4):311-320
Measles virus (MV) infection primarily targets epithelial cells of the respiratory tract, which have the potential to synthesize a variety of cytokines. In this report, we studied the effect of MV infection on the production of interleukin (IL)-8 by the pulmonary epithelial cells. A549 cells, a lower airway epithelial cell line, produced IL-8 after MV inoculation in a dose- and time-dependent manner. The IL-8 production was little affected by UV-inactivation of MV and scarcely suppressed by cycloheximide treatment. These results indicated that MV particle binding to and/or incorporation into cells stimulated IL-8 expression in A549 cells. 相似文献
138.
The effect of pretreatment with different doses of GnRH to synchronize follicular wave on superstimulation of follicular growth in dairy cattle 总被引:1,自引:0,他引:1
Sato T Nakada K Uchiyama Y Kimura Y Fujiwara N Sato Y Umeda M Furukawa T 《The Journal of reproduction and development》2005,51(5):573-578
The objective of this study was to evaluate the efficiency of gonadotropin releasing hormone (GnRH) and GnRH doses in synchronizing follicular wave emergence as a pretreatment for superovulation in cattle. Fourteen Holstein-Friesian cows 6 days from estrus were randomly assigned to receive 100 microg (n=4), 50 microg (n=5), or 25 microg (n=5) of GnRH. Superovulation was induced with injections of porcine FSH (pFSH) twice daily, decreasing the dose (total 42 AU) over 5 days beginning 2.5 days after receiving GnRH. On the 7th and 8th injections of pFSH, 750 microg of PGF(2alpha) was also given. With the exception of one cow that was given 50 microg of GnRH, ovulation was induced in all cows from the three groups and the new follicular wave emergence was observed. The total number of follicles for the 25 microg GnRH group was less than that observed for the 100 microg GnRH group (P<0.05), although there were no differences between the 100 microg, 50 microg and 25 microg GnRH groups with respect to the number of preovulatory follicles (>or=10 mm) and CL. The numbers of normal embryos were greater for the 25 microg GnRH group than the 100 or 50 microg GnRH groups (P<0.01); however, the numbers of ova/embryos did not differ significantly between the three groups. These results suggest that 25 microg of GnRH was sufficient to induce ovulation and follicular wave emergence. On day 6 of the estrous cycle, a reduction of the dose of GnRH to synchronize follicular wave emergence as a pretreatment for superstimulation promotes transferable embryos. 相似文献
139.
Otagiri Y Asai T Okada M Uto T Yazawa S Hirai H Shibata I Sato S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(8):801-805
We examined nasal swab and lung homogenate samples collected from pigs experimentally and naturally infected with Mycoplasma hyopneumoniae for the detection of M. hyopneumoniae by the nested PCR (nPCR) and culture methods. In the 23 experimentally infected pigs, M. hyopneumoniae was commonly detected in nasal swabs by the nPCR and culture methods at 4 weeks after inoculation, and there was a significant correlation (P<0.01) between the titers of viable organisms in nasal swabs and in lung homogenates in the experimentally inoculated pigs. In the naturally infected pigs, on the other hand, discrepancies in detection were found between nasal swab and lung homogenate samples in 17 of 36 cases, although the presence of gross lung lesions correlated relatively well with the detection of organisms from the samples. Our results indicated that the diagnosis of mycoplasmal pneumonia by nPCR in individual pigs with nasal swabs is reliable under these experimental conditions. At present, nPCR with nasal swabs should only be used for monitoring the disease status at the herd level under field conditions. 相似文献
140.
Iijima K Jiang JY Shimizu T Sasada H Sato E 《The Journal of reproduction and development》2005,51(1):161-168
To address the role of follicular angiogenesis in the determination of ovulatory follicles and the effects of different vascular endothelial growth factor (VEGF) isoforms on follicular angiogenesis and development, mature female rats were treated with an angiogenic inhibitor (TNP-470), and also with VEGF 120 or 164 at different dosages (0.4, 0.8, 4.0 or 8.0 microg/kg body weight) for 3 days during the estrous cycle. Ovarian follicular angiogenesis, the population of large follicles and ovulation were examined. VEGF 120 (0.8 microg/kg) and 164 (8.0 microg/kg) treatments stimulated follicular angiogenesis in the theca interna layer, while TNP-470 treatment showed severe depression of follicular angiogenesis, and completely inhibited ovulation. After administration of VEGF 120 or 164, the number of healthy preovulatory follicles and ovulated oocytes increased significantly, concomitantly with a decrease in the number of atretic preovulatory follicles. The oocytes ovulated had normal fertilizability and developed to term with the same litter size as in the control rats. Our findings suggest that follicular angiogenesis may be a determinant of follicular development during the periovulatory phase, and that VEGF isoforms may play different important roles in regulating follicular angiogenesis. 相似文献