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排序方式: 共有235条查询结果,搜索用时 31 毫秒
101.
接种猪圆环病毒2型(PCV2)疫苗不仅可以减少猪只的死亡,而且似乎还可以减少抗生素的使用。众多农场的例子说明了这一点。 相似文献
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Domoic acid epileptic disease is characterized by spontaneous recurrent seizures weeks to months after domoic acid exposure. The potential for this disease was first recognized in a human case study of temporal lobe epilepsy after the 1987 amnesic shellfish-poisoning event in Quebec, and was characterized as a chronic epileptic syndrome in California sea lions through investigation of a series of domoic acid poisoning cases between 1998 and 2006. The sea lion study provided a breadth of insight into clinical presentations, unusual behaviors, brain pathology, and epidemiology. A rat model that replicates key observations of the chronic epileptic syndrome in sea lions has been applied to identify the progression of the epileptic disease state, its relationship to behavioral manifestations, and to define the neural systems involved in these behavioral disorders. Here, we present the concept of domoic acid epileptic disease as a delayed manifestation of domoic acid poisoning and review the state of knowledge for this disease state in affected humans and sea lions. We discuss causative mechanisms and neural underpinnings of disease maturation revealed by the rat model to present the concept for olfactory origin of an epileptic disease; triggered in dendodendritic synapases of the olfactory bulb and maturing in the olfactory cortex. We conclude with updated information on populations at risk, medical diagnosis, treatment, and prognosis. 相似文献
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Johnson S Lowenstine L Gulland F Jang S Imai D Almy F Delong R Gardner I 《Veterinary microbiology》2006,114(1-2):94-103
To investigate the association between genital bacterial infection and urogenital carcinoma in California sea lions (Zalophus californianus), vaginal and preputial swabs for bacterial isolation were taken from 148 free-ranging and 51 stranded California sea lions including 16 animals with urogenital carcinoma. Cytological examination of vaginal or preputial smears showed a majority (65.5%, 57/87) of animals examined had mild or no inflammation. Aerobic bacteria were isolated from 116 (78.4%) wild sea lions and 100% of stranded animals. A total of 403 isolates were identified representing 51 unique bacterial species. The median number of isolates per animal increased with age in the wild group, but there was no difference in the number of isolates per animal between wild and stranded adults. The most common bacteria isolated from the wild sea lions were Psychrobacter phenylpyruvicus (39 isolates), non-hemolytic Streptococcus (35 isolates), Corynebacterium spp. (30 isolates), and Escherichia coli (20 isolates). More bacterial species were isolated from stranded animals than wild animals (33 versus 26) and there was significantly less growth of P. phenylpyruvicus, Corynebacterium spp., and Moraxella-like spp. in the stranded animals. Beta-hemolytic Streptococcus was the only bacterium significantly associated with urogenital carcinomas in California sea lions, but only in females. 相似文献
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Coleman WM Dube MF Ashraf-Khorassani M Taylor LT 《Journal of agricultural and food chemistry》2007,55(8):3037-3043
The chemical nature of davanone isolated from natural davana oil via packed column preparative supercritical fluid chromatography with a carbon dioxide-based mobile phase has been defined. Analyses used to characterize davanone included nuclear magnetic resonance spectroscopy, optical rotation, mass spectrometry, headspace solid-phase microextraction, enantiomeric purity via gas chromatography (GC), and GC-coupled olfactometry. For comparison, natural davana oil was subjected to the same types of measurements. The enriched davanone sample was nearly 100% optically pure. This indicates that fractionation of the davana oil with supercritical fluids at near room temperature had little effect on the optical integrity of the sample. 相似文献
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Landscape Ecology - Ecological design used for stormwater management—referred to as Water Sensitive Urban Design (WSUD)—exemplifies how urban environments can benefit from mimicking... 相似文献
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Wong KK Signal FA Campion SH Motion RL 《Journal of agricultural and food chemistry》2005,53(11):4633-4636
Of five commercial plant extracts (citronella, garlic oil, neem extract, pine oil, and pyrethrum), citronella was found to be effective in deterring the infestation of cartons containing muesli and wheat germ by red flour beetles. The chemical components were applied as part of a coating on the carton board. In an experimental set up that accelerates infestation over a 2 week period, citronella-treated cartons (0.2 g/m2 of carton board) reduced beetle infestation to approximately 50% of the level observed in control cartons. Evidence was provided to indicate that an insect repellent effect persists for at least 16 weeks. Additional work on the controlled release of the insect repellent would be required to prolong the effect. 相似文献