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Sheep red blood cells were fractionated by ion exchange and gel filtration chromatography to yield glutathione peroxidase approximately 99% pure. An antiserum against glutathione peroxidase was raised in the rabbit. The antiserum has been shown to cross-react with both bovine and human glutathione peroxidase by double diffusion. An enzyme linked immunosorbent assay has been developed for glutathione peroxidase which detected 6.15 X 10(-5) IU of the enzyme. The antiserum has also been shown to be effective in the detection of glutathione peroxidase immobolised on strips of nitrocellulose, subsequent to sodium dodecyl sulphate polyacrylamide gel electrophoresis, by second antibody conjugate. Avidin-biotin was also used to detect nitrocellulose immobolised enzyme. These techniques provide an alternative highly sensitive and specific means of assaying glutathione peroxidase which is not dependent on the lability of enzymatic activity nor the chemical specificity of the assay. 相似文献
693.
Objective To determine if anthropometric measurements of the Labrador scapula, humerus, ulna and radius, or their ratios, are related to the presence of elbow dysplasia (ED). Methods Digital calliper measurements of the lengths of the left scapula, humerus, radius and ulna, and their ratios, were analysed by gender in 103 volunteer Labradors (41 dogs, 62 bitches) against the ED radiological scores derived by the International Elbow Working Group (IEWG). The IEWG score is an umbrella score used to classify for ED and includes fragmented coronoid process, osteochondritis dessicans, incongruity and ununited anconeal process, the last of which occurs rarely in Labradors. Results Of the 103 Labradors studied, 31 were diagnosed radiographically with ED (20 bitches (32%), 11 (27%) dogs). Scapula length was significantly shorter for bitches with ED (P = 0.02), but not for dogs with ED. However, dogs showed a trend for a difference in the ulna:radius ratio (P = 0.06), which bitches did not. Although a greater percentage of bitches than dogs had ED in this study, the difference was not statistically significant. Conclusions Labrador bitches diagnosed with ED have a shorter scapula, which is a new finding associated with this condition. The difference in presentation associated with gender is unexpected and further research is recommended. 相似文献
694.
Matthew J. Germino David M. Barnard Bill E. Davidson Robert S. Arkle David S. Pilliod Matthew R. Fisk Cara Applestein 《Landscape Ecology》2018,33(7):1177-1194
Context
Reestablishing foundational plant species through aerial seeding is an essential yet challenging step for restoring the vast semiarid landscapes impacted by plant invasions and wildfire-regime shifts. A key component of the challenge stems from landscape variability and its effects on plant recovery.Objectives
We assessed landscape correlates, thresholds, and tipping points for sagebrush presence from fine-scale sampling across a large, heterogeneous area burned the previous year, where we were able to quantify soil surface features that are typically occluded yet can strongly affect recovery patterns.Methods
Hypothesis testing and binary-decision trees were used to evaluate factors affecting initial sagebrush establishment, using 2171 field plots (totaling?~?2,000,000 m2 sampled) over a 113,000-ha region.Results
Sagebrush established in 50% of plots where it was seeded, a?>?12-fold greater establishment frequency than in unseeded areas. Sagebrush establishment was enhanced in threshold-like ways by elevation (>?1200 m ASL), topographic features that alter heatload and soil water, and by soil-surface features such as “fertile islands” that bore the imprint of pre-fire sagebrush. Sagebrush occupancy had a negative, linear relationship with exotic-annual grass cover and parabolic relationship with perennial bunchgrasses (optimal at 40% cover).Conclusions
Our approach revealed interactive, ecological relationships such as novel soil-surface effects on first year establishment of sagebrush across the burned landscape, and identified “hot spots” for recovery. The approach could be expanded across sites and years to provide the information needed to explain past seeding successes or failures, and in designing treatments at the landscape scale.695.
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Warnock JJ Marks SL Pollard R Kyles AE Davidson A 《Journal of the American Veterinary Medical Association》2003,223(10):1462-1468
OBJECTIVE: To determine outcome of and complications associated with cricopharyngeal myotomy or myectomy for treatment of cricopharyngeal dysphagia (CPD) in dogs. DESIGN: Retrospective study. ANIMALS: 14 dogs. PROCEDURE: Medical records of dogs with CPD that underwent cricopharyngeal myotomy or myectomy were examined. Follow-up information was obtained through telephone interviews with owners and referring veterinarians and clinical examinations when feasible. RESULTS: 16 surgical procedures were performed on the 14 dogs. Dysphagia was completely resolved immediately after surgery in 1 dog, and clinical signs did not recur (follow-up time of 8 years); a second dog also had immediate complete resolution of dysphagia, but follow-up time was only 10 days. Three dogs had transient complete resolution with a mean time to recurrence of dysphagia of 12.3 weeks (range, 2 to 36 weeks). Three dogs had permanent partial resolution. Six dogs had no improvement after surgery. Eight of the 14 dogs were euthanatized because of problems related to CPD, including persistent dysphagia (n = 8) and aspiration pneumonia (5). CONCLUSIONS AND CLINICAL RELEVANCE: The failure rate for dogs undergoing surgical treatment of CPD may be high, particularly if concurrent aspiration pneumonia or malnutrition is not addressed prior to surgery. For those dogs with concurrent diseases, more aggressive medical management, such as enteral tube feeding, may be warranted rather than surgery. In dogs with CPD complicated by other anatomic or functional conditions, such as myasthenia gravis, laryngeal paralysis, and esophageal stricture, surgery may also not be indicated. 相似文献
700.
An integrated hydro-economic modelling framework to evaluate water allocation strategies I: Model development 总被引:2,自引:0,他引:2
Biju George Hector MalanoBrian Davidson Petra HellegersLuna Bharati Sylvain Massuel 《Agricultural Water Management》2011,98(5):733-746
In this paper an integrated modelling framework for water resources planning and management that can be used to carry out an analysis of alternative policy scenarios for water allocation and use is described. The modelling approach is based on integrating a network allocation model (REALM) and a social Cost Benefit economic model, to evaluate the physical and economic outcomes from alternative water allocation policies in a river basin or sub-basin. From a hydrological perspective, surface and groundwater models were first applied to assess surface and groundwater resource availability. Then an allocation model was applied to reconcile the calculated surface and groundwater resources. From an economic perspective initially the value of water allocated to different uses in each demand centre within the system was estimated. These values were then placed in a social Cost Benefit Analysis to assess the economic consequences of different allocation scenarios over time and space. This approach is useful as it allows policymakers to consider not only the physical dimensions of distributing water, but also the economic consequences associated with it. This model is considered superior to other models as water is increasingly being seen as an economic good that should be allocated according to its value. The framework outlined in this paper was applied to the Musi sub-basin located in the Krishna Basin, India. In applying this framework it was concluded that competition for Musi water is very high, the transfer of water from agriculture to urban users is likely to grow in future and the value of water used in different agricultural zones is very low. 相似文献