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排序方式: 共有137条查询结果,搜索用时 31 毫秒
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Lamont LA Greene SA Grimm KA Tranquilli WJ 《American journal of veterinary research》2004,65(1):93-98
OBJECTIVE: To determine the relationship between bispectral index (BIS) and minimum alveolar concentration (MAC) multiples of sevoflurane in cats. ANIMALS: 8 domestic cats. PROCEDURE: Each cat was anesthetized twice with sevoflurane. First, the MAC of sevoflurane for each cat was determined by use of the tail clamp method. Second, cats were anesthetized with sevoflurane at each of 5 MAC multiples administered in random order. Ventilation was controlled, and after a 15-minute equilibration period at each MAC multiple of sevoflurane, BIS data were collected for 5 minutes and the median value of BIS calculated. RESULTS: The mean (+/- SD) MAC of sevoflurane was 3.3 +/- 0.2%. The BIS values at 0.5 MAC could not be recorded as a result of spontaneous movement in all 8 cats. The BIS values at 2.0 MAC were confounded by burst suppression in all 8 cats. Over the range of 0.8 to 1.5 MAC, BIS values decreased significantly with increasing end-tidal sevoflurane concentrations. Mean (+/- SD) BIS measurements were 30 +/- 3, 21 +/- 3, and 5 +/- 2 at 0.8, 1.0, and 1.5 MAC, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Values of BIS are inversely and linearly related to end-tidal sevoflurane concentrations in anesthetized cats, and BIS may be a useful predictor of CNS depression in this species. The consistently low BIS values recorded in this study suggest that clinical BIS end points used to titrate anesthetic agents in humans may not be applicable to cats. 相似文献
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Krecek RC Michael LM Schantz PM Ntanjana L Smith MF Dorny P Harrison LJ Grimm F Praet N Willingham AL 《Veterinary parasitology》2008,154(1-2):38-47
The pork tapeworm, Taenia solium, causative organism of porcine cysticercosis and human neurocysticercosis is known to occur in areas of South Africa including Eastern Cape Province but, despite increasing reports of its occurrence throughout the subregion, the prevalence is yet to be clearly established. The parasite presents a potentially serious agricultural problem and public health risk in endemic areas. The human populations considered to be at highest risk of infection with this zoonotic helminth are people living in rural areas most of whom earn their livelihood wholly or partially through livestock rearing. Here we report on initial results of a community-based study of pigs owned by resource-poor, emerging pig producers from 21 villages in the Eastern Cape Province. Lingual examination (tongue palpation) in live pigs, two enzyme-linked immunosorbent assays (ELISAs), which detect parasite antigen (B158/B60 Ag-ELISA and HP10 Ag-ELISA) and an enzyme immunotransfer blot (EITB) assay, which detects antiparasite antibody, were used to verify endemicity and estimate apparent prevalence. In the absence of a gold standard true prevalence was obtained, using a Bayesian approach, with a model that uses both available data and prior information. Results indicate that the parasite is indeed present in the study villages and that true prevalence was 64.6%. The apparent prevalences as measured by each of the four tests were: 11.9% for lingual examination, 54.8% for B158/B60 Ag-ELISA, 40.6% for HP10 Ag-ELISA and 33.3% for EITB. This base-line knowledge of the prevalence of T. solium in pigs provides information essential to the design and monitoring of sustainable and appropriate interventions for cysticercosis prevention and control. 相似文献
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David Bruce Lewis Nancy B. Grimm Tamara K. Harms John D. Schade 《Landscape Ecology》2007,22(6):911-924
Nutrient dynamics in rivers affect biogeochemical fluxes from land to oceans and the atmosphere. Fluvial ecosystems are thus
important environments for understanding spatial variability in nutrient concentrations. At the San Pedro River in semi-arid
Arizona, USA, we investigated how variability in dissolved inorganic nitrogen (DIN) was regulated by subsystem type and hydrological
flowpaths. The three subsystems we compared were the riparian zone, parafluvial (gravel bar) zone, and surface stream. DIN
concentration was greater in the riparian zone than in the surface stream, suggesting that the riparian zone retains DIN and
is a source of N for the surface stream. Parafluvial zones were too variable to generalize how they regulate DIN. Our hypothesis
that subsystem type regulates DIN oxidation was too simple. The riparian and parafluvial zones host a mosaic of oxidizing
and reducing conditions, as they exhibited highly variable ammonium to nitrate (NH4+:NO3−) ratios. Surface stream DIN was dominated by NO3−. Along a subsurface flowpath in the riparian zone, we did not observe spatial covariation among the N forms and transformations
involved in mineralization. We also compared spatial variability in solute concentrations between flowpaths and non-flowpath
reference areas. Our mixed results suggest that spatial variability is regulated in part by flowpaths, but also by solute-specific
processing length along a flowpath. To understand the distribution of N in fluvial ecosystems, subsystem type and flowpaths
are readily discernable guides, but they should be coupled with other mechanistic factors such as biota and soil type. 相似文献
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A survey on taxonomy, diagnosis, distribution and pathogenicity of Cryptococcus neoformans is given. The investigation presented here concerns 1046 fecal samples of avian species, which can be kept in the living area of humans. All together only 15 strains have been isolated, 9 of which originated from the same breeder. 相似文献
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Bose-Einstein condensation of cesium atoms is achieved by evaporative cooling using optical trapping techniques. The ability to tune the interactions between the ultracold atoms by an external magnetic field is crucial to obtain the condensate and offers intriguing features for potential applications. We explore various regimes of condensate self-interaction (attractive, repulsive, and null interaction strength) and demonstrate properties of imploding, exploding, and non-interacting quantum matter. 相似文献