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21.
Terry C. Gerros DVM MS John S. Mattoon DVM Stanley P. Snyder DVM PHD 《Veterinary radiology & ultrasound》1998,39(4):322-324
A 7-month-old La Mancha doe was presented with a right head tilt and ventral strabismus while circling to the left. History and physical examination led to a tentative diagnosis of a cerebral abscess. Computed tomography revealed a large, complex mass with ring enhancement in the left cerebral hemisphere, supporting the diagnosis. Postmortem examination confirmed the cerebral abscess. Bacterial cultures yielded heavy growth of Actinomyces pyogenes. 相似文献
22.
Isolation of a monoclonal antibody with specificity for commonly employed vaccine strains of Newcastle disease virus 总被引:2,自引:0,他引:2
A monoclonal antibody, AVS-I, was produced from a hybridization of murine myeloma cells and splenocytes from mice immunized with the La Sota strain of Newcastle disease virus (NDV). The hybridoma producing AVS-I, selected from 184 NDV-positive supernatants, is one of two supernatants that reacted exclusively with lentogenic strains in an indirect enzyme-linked immunosorbent assay. AVS-I can also be assayed by hemagglutination-inhibition (HI), which was used to test selected reference avian paramyxovirus (PMV) strains of types 1 to 3. NDV vaccines La Sota and B1 and field isolates from chickens, turkeys, pigeons, and cockatoos were also used as antigens. AVS-I had a high binding affinity for all La Sota and B1 strains, including vaccines. The antibody bound with a lower titer to the Australian Queensland V4 and Ulster strains, but it did not bind to the F strain, a lentogenic strain from England. AVS-I was HI-negative against the other PMV reference strains. AVS-I may be valuable for identifying field isolates antigenically similar to La Sota and B1 and rapidly differentiate those vaccine strains from more virulent viruses. 相似文献
23.
Snyder CW 《Science (New York, N.Y.)》1967,158(3809):1665-1669
On 19 October 1967 the Mariner V spacecraft passed by Venus 10,151 kilometers from the center of the planet; the gravitational field, atmosphere, ionosphere, hydrogen corona, and interaction with the solar wind were observed. 相似文献
24.
Classical ecological theory suggests that the coexistence of consumer species is fostered by resource-use differences, leading to greater resource use in communities with more species. However, explicit empirical support for this idea is lacking, because resource use by species is generally confounded with other species-specific attributes. We overcame this obstacle by co-opting behavioral plasticity in food choice among a group of animal consumers, allowing us to manipulate patterns of resource use while controlling for the effects of species identity and diversity. Within an aphid-parasitoid-radish community, we created a fully factorial manipulation of consumer resource-use breadth (specialist versus generalist) and species diversity (one versus three species) and found that resource exploitation improved with greater specialist, but not generalist, diversity. Therefore, resource partitioning, and not diversity per se, fostered greater overall resource consumption in our multispecies consumer communities. 相似文献
25.
T. J. Sullivan J. R. Webb K. U. Snyder A. T. Herlihy B. J. Cosby 《Water, air, and soil pollution》2007,182(1-4):57-71
A geologic classification scheme was combined with elevation to test hypotheses regarding watershed sensitivity to acidic deposition using available regional spatial data and to delimit a high-interest area for streamwater acidification sensitivity within the Southern Appalachian Mountains region. It covered only 28% of the region, and yet included almost all known streams that have low acid neutralizing capacity (ANC ≤20 μeq l?1) or that are acidic (ANC ≤0). The five-class geologic classification scheme was developed based on recent lithologic maps and streamwater chemistry data for 909 sites. The vast majority of the sampled streams that had ANC ≤20 μeq l?1 and that were totally underlainby a single geologic sensitivity class occurred in the siliceous class, which is represented by such lithologies as sandstone and quartzite. Streamwater acid-base chemistry throughout the region was also found to be associated with a number of watershed features that were mapped for the entire region, in addition to lithology and elevation, including ecoregion, physiographic province, soils type, forest type and watershed area. Logistic regression was used to model the presence/absence of acid-sensitive streams throughout the region. 相似文献
26.
OBJECTIVE: To evaluate single and double layer end-to-end anastomosis in equine jejunum. STUDY DESIGN: Experimental in vitro study. ANIMALS: Mid-jejunal sections from 12 adult horses without gastrointestinal disease. METHODS: Jejunal end-to-end anastomoses were performed by a continuous Lembert pattern or a simple continuous pattern oversewn with a Cushing pattern. Jejunal segments were distended with fluid at 1 L/min, and intraluminal pressure at failure, and mode of failure were recorded. Bursting pressure and bursting wall tension were calculated. Anastomosis construction time and degree of luminal reduction were recorded. Results- Single layer anastomoses were constructed in less time than 2-layer anastomoses. Both anastomotic techniques resulted in luminal reduction compared with control tissue; however, the reduction was smaller with a 1-layer continuous Lembert anastomosis. No differences were noted in bursting pressure or bursting wall tension between groups. CONCLUSIONS: Anastomosis using a 1-layer continuous Lembert pattern resulted in a larger stoma, was faster to perform, and as strong as a 2-layer anastomosis. CLINICAL RELEVANCE: Use of a 1-layer continuous Lembert pattern for jejunojejunosotomy may be beneficial by decreasing anastomosis time and produce a larger stoma than a 2-layer anastomosis. 相似文献
27.
E S Williams J C DeMartini S P Snyder 《American journal of veterinary research》1985,46(11):2317-2321
The efficacy of the lymphocyte blastogenesis and complement-fixation tests and fecal culture for detection of Mycobacterium paratuberculosis infection was assessed in bighorn sheep (Ovis canadensis), elk (Cervus elaphus nelsoni), mule deer (Odocoileus hemionus), white-tailed deer (O virginianus), bighorn X mouflon (O musimon) hybrid sheep, and domestic sheep. Spontaneously infected bighorns were tested at the time of capture; experimentally infected animals were tested monthly for 12 months or periodically for 36 months. Lymphocyte blastogenesis tests were conducted with peripheral blood mononuclear cells and protein antigens of M avium, M bovis, and M paratuberculosis. Best diagnostic results were obtained when M avium purified-protein derivative was used as antigen and 20% bovine fetal serum was incorporated in the culture medium; a positive test was defined as a stimulation index greater than or equal to 3.5. Test sensitivity and specificity, respectively, were 82% and 94% in hybrid sheep and were 72% and 100% in domestic sheep. Sensitivity and specificity, respectively, were 39% and 94% in elk and 53% and 92% in deer. When infection was determined in spontaneously infected bighorns by culture of M paratuberculosis and/or the presence of acid-fast bacilli in characteristic microscopic lesions, sensitivity was 75% and specificity was 87%. Fecal cultures and the complement-fixation tests seldom correctly identified infected animals. 相似文献
28.
29.
Recently Infectious Bursal Disease Virus isolates have been described in USA displaying an antigenic drift. Many of the new isolates were very virulent for chickens. In several European countries severe outbreaks of Gumboro disease have also been reported from vaccinated and non-vaccinated flocks. Since vaccinated SPF birds were shown to be protected against challenge infection with the new isolates under laboratory conditions, a more detailed investigation of the European isolates is wanted. The similarity between the European and US field situation got us to use a panel of monoclonal antibodies (MCAs) previously applied to characterize US strains for testing European isolates. An antigen capture ELISA has been carried out directly on bursa homogenates of chickens form the field. One European (F52/70) and two US (Var. E and GLS-5) strains have been included as reference viruses. From the results presented here it can be concluded that the European isolates (Netherlands, France, UK, Germany, Jugoslavia and Spain) did not undergo the same antigenic drift as the US strains. A more extensive analysis of the isolates will be done to elucidate their role for disease outbreaks. 相似文献
30.