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排序方式: 共有343条查询结果,搜索用时 15 毫秒
321.
A J Sinclair D H Embury I J Smart D A Barr R L Reece P T Hooper J A Gould 《The Veterinary record》1984,115(19):485-488
A number of plasma biochemical parameters were examined in five outbreaks of runting in broiler chickens. In four of the five outbreaks, runts showed consistent elevations in plasma amylase activity and reductions in glutathione peroxidase activity. In two of the five outbreaks the plasma vitamin E concentration was reduced, as was the activity of plasma alkaline phosphatase. A highly significant number of runted chickens were found to have pancreatic degeneration, elevated plasma amylase activity and reduced plasma glutathione peroxidase activity, compared with non-runted chickens. The implications of these changes are discussed in relation to the aetiology of runting and stunting syndrome and, in particular, the possible involvement of selenium. 相似文献
322.
W J Gould A E Yaegar J C Glennon 《Journal of the American Veterinary Medical Association》1992,200(5):705-706
Ingested scutes caused an intestinal obstruction in an 18-year-old turtle. An enterotomy, performed through a flank approach to the celiac cavity, successfully relieved the obstruction. The scutes were ingested during a period of neglect by the owner. 相似文献
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325.
Polycythemia vera in a cat 总被引:1,自引:0,他引:1
326.
Polioencephalomalacia (PEM) was induced in calves by feeding a semipurified, low-roughage diet of variable copper and molybdenum composition. Two formulations resulting in Cu-insufficient and Cu-sufficient forms of the diet were fed (n = 10 and 4 calves, respectively); both diets induced PEM. Clinical signs of disease developed as early as 15 days after transition to the experimental diets and included impaired vision, decreased response to external stimuli, and abnormal gait. Grossly evident cerebrocortical lesions consisted of laminar areas of cavitation and/or autofluorescence seen under UV illumination. Hepatic Cu concentration was decreased in calves fed the Cu-insufficient diet, but not below normal range. During the course of feeding either diet, rumen pH decreased, rumen volatile fatty acid concentrations increased, rumen and blood lactic acid concentrations increased, and rumen and plasma thiamine concentrations increased. The thiamine pyrophosphate effect on erythrocyte transketolase activity was unaltered in calves of either diet group. This nutritionally induced form of PEM does not appear to be related to Cu deficiency or reduction in plasma or rumen thiamine concentration. 相似文献
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328.
Virus-induced gene silencing as a tool for functional analyses in the emerging model plant Aquilegia (columbine, Ranunculaceae) 总被引:1,自引:0,他引:1
Background
There is considerable interest in rapid assays or screening systems for assigning gene function. However, analysis of gene function in the flowers of some species is restricted due to the difficulty of producing stably transformed transgenic plants. As a result, experimental approaches based on transient gene expression assays are frequently used. Biolistics has long been used for transient over-expression of genes of interest, but has not been exploited for gene silencing studies. Agrobacterium-infiltration has also been used, but the focus primarily has been on the transient transformation of leaf tissue. 相似文献329.
Cannon M Gould D Caney S Foster D Harvey A Reed N Sparkes A Tasker S Van de Stadt-Gould M 《The Veterinary record》2007,160(1):32; author reply 32
330.
Christopher M. Richards Michael F. Antolin Ann Reilley Jackie Poole Christina Walters 《Genetic Resources and Crop Evolution》2007,54(4):837-848
Genebanks complement other conservation programs because they preserve genetic diversity needed for future breeding and restoration.
We evaluated efficiency of capturing genetic diversity, using endangered Zizania texana (Texas wild rice) as a model for plants with recalcitrant seeds. This perennial aquatic grass is restricted to 4 km of the
San Marcos River in Texas. An early conservation collection included plants from stands throughout the river, based on the
assumption stands would be unique genotypes. Using microsatellite markers, we found that genetic diversity was concentrated
in five of 15 large, demographically stable stands; 96 stands smaller than 2 m2 contributed no unique alleles. High heterozygosity and few duplicate genotypes suggested that sexual reproduction occurs
more often than presumed. Simulations of stratified sampling of large stands captured all alleles in only 45 individuals,
while random sampling along the river captured much less diversity. The early conservation collection captured as much diversity
as expected from random sampling. Texas wild rice stands resemble a mainland-island metapopulation; our analyses suggest that
stratified sampling maximizes genetic diversity for this population dynamic. Demographic and genetic information is important
for validating the design of efficient ex situ collections and guiding in situ conservation. 相似文献