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排序方式: 共有1604条查询结果,搜索用时 31 毫秒
41.
Miller MW Fossum TW Bahr AM 《Journal of the American Veterinary Medical Association》2002,221(11):1586-90, 1574
Transvenous retrograde portography for identification and characterization of portosystemic shunts in dogs A method for transvenous retrograde portography (TRP) in dogs suspected to have a portosystemic shunt (PSS) and results in 20 dogs are described. For TRP, dogs were anesthetized and positioned in left lateral recumbency A dual-lumen balloon-tipped catheter was inserted into the right jugular vein and advanced into the azygos vein. The balloon was inflated to occlude the azygos vein, and contrast material was injected during fluoroscopic evaluation. The catheter was then positioned in the caudal vena cava just cranial to the diaphragm. The balloon was again inflated to occlude the vena cava, and contrast material was again injected. Once a shunt was identified, selective catheterization was attempted with a guide wire and angled catheter. A PSS was identified in 18 of the 20 dogs. In 10 of the 18, the shunt vessel could be selectively catheterized, allowing measurement of portal pressures while the shunt was occluded with the balloon. In 1 dog, results of TRP were normal, but subsequent exploratory celiotomy revealed a single extrahepatic PSS, which was surgically attenuated. The other dog in which results of TRP were normal did not have a macroscopic PSS. In dogs suspected to have a PSS, TRP may be a useful adjunctive diagnostic test that is less invasive than operative mesenteric vein portography and allows measurement of portal pressures before and after temporary shunt occlusion. 相似文献
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Fifty canine fecal samples were evaluated by five flotation procedures to compare the sensitivity of the zinc sulfate (ZnSO4) centrifugation flotation test with ZnSO4 flotation tests using benchtop incubation during the flotation period. One or more parasite species were detected in 40 samples. Results showed that centrifugation with ZnSO4 solution was significantly more likely to detect a positive sample than benchtop procedures. The difference in procedures was due primarily to increased detection of Trichuris eggs and Giardia cysts by centrifugal flotation. No significant difference was seen in the ability of benchtop procedures to detect positive samples when tests sat either for 5 or 10 minutes before examination. 相似文献
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Muhle AC Jaggy A Stricker C Steffen F Dolf G Busato A Kornberg M Mariscoli M Srenk P Gaillard C 《Veterinary journal (London, England : 1997)》2002,163(3):247-318
Sensorineural deafness is a common congenital disorder in Dalmatians and is genetically transmitted. Different modes of inheritance have been proposed and the objective of this study was to study these by segregation analyses using maximum likelihood procedures. Data from 33 complete Dalmatian families were collected and data from 56 single Dalmatians added. This resulted in a total of 575 dogs with 357 known phenotypes. All dogs were clinically evaluated and electrophysiologically tested with brainstem auditory evoked responses.The prevalence of deafness was 16.5% (9.4% unilaterally deaf, 7.1% bilaterally deaf). Females were 4.4% more affected than males but this difference was not significant. Within the same litter, different phenotypic expressions of deafness occurred, which suggested different expressions of the disease. In addition, two data sets were analysed: the first included normal, uni- and bilaterally deaf dogs, the second had normal and deaf Dalmatians. We found that a recessive allele at a single biallelic major locus fitted our data best, although an incomplete penetrance of the recessive homozygotes was observed. 相似文献
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This article offers information regarding selected veterinary information resources, along with basic search strategies for locating clinical evidence within these resources. No one database provides adequate indexing and abstracting to all literature relevant to the veterinary clinical question. An understanding of a database's syntax and field structure is necessary to formulate a functional search strategy and evaluate the outcome of search results. Flexibility when identifying, selecting, and combining search terms is also required to avoid overlimiting a search. 相似文献
47.
Ariena H. C. van Bruggen Alexander M. Semenov Anne D. van Diepeningen Oscar J. de Vos Wim J. Blok 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(1):105-122
A healthy soil is often defined as a stable soil system with high levels of biological diversity and activity, internal nutrient
cycling, and resilience to disturbance. This implies that microbial fluctuations after a disturbance would dampen more quickly
in a healthy than in a chronically damaged and biologically impoverished soil. Soil could be disturbed by various processes,
for example addition of a nutrient source, tillage, or drying-rewetting. As a result of any disturbance, the numbers of heterotrophic
bacteria and of individual species start to oscillate, both in time and space. The oscillations appear as moving waves along
the path of a moving nutrient source such as a root tip. The phase and period for different trophic groups and species of
bacteria may be shifted indicating that succession occurs. DGGE, Biolog and FAME analysis of subsequent populations in oscillation
have confirmed that there is a cyclic succession in microbial communities. Microbial diversity oscillates in opposite direction
from oscillations in microbial populations. In a healthy soil, the amplitudes of these oscillations will be small, but the
background levels of microbial diversity and activity are high, so that soil-borne diseases will face more competitors and
antagonists. However, soil-borne pathogens and antagonists alike will fluctuate in time and space as a result of growing plant
roots and other disturbances, and the periods and phases of the oscillations may vary. As a consequence, biological control
by members of a single trophic group or species may never be complete, as pathogens will encounter varying populations of
the biocontrol agent on the root surface. A mixture of different trophic groups may provide more complete biological control
because peaks of different trophic groups occur at subsequent locations along a root. Alternatively, regular addition of soil
organic matter may increase background levels of microbial activity, increase nutrient cycling, lower the concentrations of
easily available nutrient sources, increase microbial diversity, and enhance natural disease suppression. 相似文献
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Anne E. Desjardins Mark Busman Michael Muhitch Robert H. Proctor 《Physiological and Molecular Plant Pathology》2007,70(4-6):149-160
Zea mays often is colonized with the fungus Gibberella moniliformis, which produces fumonisin toxins. The role of fumonisins in seedling colonization and blight was studied using complementary genetic analyses of host and pathogen. Only one of two fumonisin B1 (FB1)-insensitive maize backcross lines was more resistant than the FB1-sensitive parent to seedling blight, indicating that the increase in FB1-insensitivity was not associated with an increase in resistance. FB1-producing and nonproducing isogenic fungal strains did not differ in ability to cause seedling blight, but the FB1-producing strain was more effective in systemic colonization of seedlings in reciprocal strain challenge tests. Together, these and previous results indicate that the role of fumonisins depends on complex environmental and genetic contexts in this host–pathogen interaction. 相似文献