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排序方式: 共有220条查询结果,搜索用时 265 毫秒
211.
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R R Tramontin R C Giles C B Hong L E Newman 《Journal of the American Veterinary Medical Association》1983,183(11):1263-1265
Skeletal or cardiac myodegeneration, or both, was observed in 4 free-ranging female white-tailed deer that were found dead or recumbent and unable to rise. Gross pathologic findings included white or chalky streaks in heart or skeletal musculature. Degeneration, necrosis, and mineralization were observed microscopically in affected striated muscles. Although the precise cause of myodegeneration was not determined, changes were considered compatible with nutritional or exertional myopathy. 相似文献
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Ramírez-Venegas G. De Ita-Pérez DL. Díaz-Muñoz M. Méndez I. García-Gasca T. Ahumada-Solórzano M. Zambrano-Estrada X. Vázquez-Martínez O. Guzmán-Maldonado H. Luna-Moreno D. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(3):297-303
Plant Foods for Human Nutrition - Time-restricted feeding and food enriched in polyphenols are strategies to prevent or reduce metabolic disorders. Bean leaves (Phaseolus vulgaris L.) are a... 相似文献
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John Salmeron Caius Rommens Susan Barker Francine Carland Giles Oldroyd Anand Mehta Douglas Dahlbeck Brian Staskawicz 《Euphytica》1994,79(3):195-200
The bacterial speck disease of tomato has been developed as a model system to elucidate the molecular basis of specificity in plant-bacterial interactions and to study signal transduction events involved in the expression of plant disease resistance. We have employed a mutagenic approach to define the steps involved in the expression of disease resistance to the bacterial pathogen, Pseudomonas syringae pv. tomato (Pst) Eleven disease susceptible mutants have been identified and characterized twith altered recognition of Pst strains that express the avirulence gene avrPto. Genetic analysis of these mutants has revealed that they fall into two complementation groups. Five of the mutants map at the Pto locus, while six map a new locus that we have termed Prf. Further characterization of these mutants has revealed that the mutants that map at Pto are still sensitive to the insecticide fenthion, while the prf mutants are altered in resistance and also are insensitive to fenthion. Genetic mapping has also determined that the Prf locus maps near Pto. We are currently employing a map-based cloning strategy to isolate the Prf locus. 相似文献
217.
Uptake of vegetative cells of Azotobacter vinelandii into protoplasts of the mycorrhizal fungus Rhizopogon sp. can be induced by treatment with polyethylene glycol (molecular weight, 6000). An L-form of the bacteria has been selected for within the differentiated fungal mycelium which is capable of acetylene reduction and nitrogen fixation, as confirmed by nitrogen-15 assays; this allows the fungus to grow on media lacking any combined nitrogen. The fungus grows and reduces acetylene on concentrations of antibiotics that prevent the growth and activity of free-living Azotobacter. Electron microscopy has revealed modified mitochondrial forms or included bacterial L-forms surrounded by an extra fungal membrane within the hyphae of the modified strains. Poly-beta-hydroxybutyric acid, a storage product of Azotobacter cysts, has also been identified in the hyphae. This would appear to be the first report of the transgenosis for acetylene reduction activity and nitrogen fixation into a eukaryote cell. 相似文献
218.
Late Tertiary silicic ashflow tuffs and lavas peralkaline in chemical character (atomic Na + K greater than Al), mainly comendites, occur over wide areas in northwestern Nevada and appear to be widespread in southeastern Oregon. Such peralkaline rocks-which are not uncommon in the western United States-and other chemically unusual silicic rocks are found near the margins rather than toward the center of the Great Basin. 相似文献
219.
A stratiform, massive copper sulfide deposit with possible gold, silver, and cobalt credits was discovered by a United Nations reconnaissance team in Paleozoic (?) metamorphic terrain of north central Turkey. The deposit, which is of possible volcanigenic exhalative origin, contains evidence of extensive prehistoric underground mining and smelting activity that, based on radiocarbon data, may date to 2800 B.C. (Early Bronze I Age). 相似文献
220.
Rachel N. Hofer Allen Lin Benjamin C. House Christopher N. Purvis Bradley J. Harris Steven J. K. Symes David K. Giles 《Journal of fish diseases》2023,46(1):31-45
Aeromonas salmonicida is a Gram-negative bacterium that can infect a wide host range of fish populations, including salmonids and non-salmonids as well as freshwater and marine life. Some strains of A. salmonicida cause the disease furunculosis, which can cause lethargy, intestinal inflammation, ulcers, haemorrhaging and death. The infection is spread through fish-to-fish contact, and the presence of infection can have devastating effects on cultivated fish populations. The purpose of this study was to explore the ability of non-A-layer and A-layer A. salmonicida strains to incorporate polyunsaturated fatty acids (PUFAs) into their lipid profile and test the phenotypic effects thereof. Lipids were extracted from PUFA-exposed cultures and analysed for lipid modification by thin-layer chromatography and ultraperformance liquid chromatography-mass spectrometry, showing A. salmonicida, regardless of A-layer, capable of incorporating all seven of the PUFAs studied. Phenotypic effects were determined through the use of assays that tested for biofilm formation, membrane permeability and cyclic peptide susceptibility. Temperature-dependent effects on biofilm formation were observed, and PUFA exposure showed significant (p < .001) increases in membrane permeability as tested by the uptake of the hydrophobic compounds crystal violet and ethidium bromide. Additionally, some PUFAs elicited modest protection and vulnerability against the membrane-targeting cyclic peptides polymyxin B (PMB) and colistin. The diverse, strain-specific responses to exogenous PUFAs may allude to evolved adaptive strategies that enhance survival, persistence and virulence of non-pathogenic and pathogenic members of bacteria that oscillate between environmental and fish host niches. 相似文献