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51.
ObjectiveTo determine whether preoperative electrocardiographic measurements linked to sympathetic nervous activity could be used to predict recovery quality after general anaesthesia in horses.Study designProspective, clinical study.AnimalsEighteen adult client-owned horses.MethodsThe electrocardiogram (ECG) was recorded presurgery in horses under three standard conditions: stabled unattended; with a groom whilst being led along a standard course; alone in the induction box. After surgery, each animal's recovery quality was scored by eight experienced anaesthetists or technicians using Donaldson's scoring system (2000). The digitized ECG recordings were analyzed for T-wave morphology, mean heart rate (HR), HR variability (HRV) and HRV derivatives including mean R-R interval, standard deviation of normal intervals (SDNN) and the root mean square of successive intervals (RMSSD), low (LF) and high frequency (HF) activity and the LF/HF ratio in both fast Fourier transformed and autoregressive spectra. Correlations between ECG variables and recovery score were examined using Spearman's rank correlation.ResultsThere was no significant correlation between preanaesthetic ECG measurements and recovery quality.ConclusionsPredictions of recovery quality after general anaesthesia in horses cannot be based on preanaesthetic ECG variables.Clinical relevanceMeasures other than those based on the ECG should be investigated as predictors of recovery quality.  相似文献   
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Three experiments (Exp. 1, n = 144 broilers [Ross × Ross]; Exp. 2, n = 118 mallard ducklings [Anas platyrhynchos]; and Exp. 3, n = 75 mature mallard ducks) were conducted to determine the effects of 3 levels of unmilled hybrid rice on growth performance and organ and gastrointestinal tract development. The dietary treatments were 1) corn-soybean meal (basal), 2) basal + 5% hybrid rice, and 3) basal + 10% hybrid rice for Exp. 1 to 3, respectively. One bird from each pen in Exp. 1 (n = 24) and all the birds in Exp. 2 (n = 118) and Exp. 3 (n = 75) were randomly selected and euthanized to determine linear measurements and organ and gastrointestinal tract weight. In Exp. 1 and 2, birds fed 10% rice experienced slower growth (P < 0.05) than birds fed the basal diet. In Exp. 3, the addition of rice did not affect growth performance. Rice addition did not affect organ length or weight (P > 0.05) in Exp. 1. However, birds fed 5% rice had significantly increased (P < 0.05) pancreas, ileum, and jejunum weights in Exp. 2, and 10% rice significantly increased (P < 0.05) liver weight in Exp. 3. The addition of 10% unmilled rice to broiler and duck diets may reduce growth performance.  相似文献   
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Zimbabwe embarked on planting Eucalyptus species in the early 1900s. Based on a robust breeding programme, it has become a major source of seed for other countries in and outside Africa. Tree health surveys conducted on Eucalyptus in some east and southern African countries over the past two decades have revealed several important fungal diseases that were previously not known in the region, but little is known regarding these problems in Zimbabwe. The aim of this study was to identify important Eucalyptus diseases across Zimbabwe's agroclimatic regions. Morphological characteristics and DNA sequence data were used to identify pathogens collected to species level. Widespread stem canker diseases, caused by species belonging to the Botryosphaeriaceae and Teratosphaeriaceae, and leaf spot diseases caused by fungi in the Capnodiales, were identified. Armillaria root and stem rot was restricted to a single site in the Eastern Highlands. Fungi that could cause canker or blue stain of timber were isolated from recently harvested stumps and included species of Ceratocystis and Ophiostoma. This study is the first to identify Eucalyptus pathogens to species level in Zimbabwe and we report for the first time the presence of the stem canker pathogen T. gauchensis in southern Africa. The results will provide a foundation for the formulation of future disease management strategies in the country.  相似文献   
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Glyphosate resistance evolution in weeds is a growing problem in world agriculture. Here, we have investigated the mechanism(s) of glyphosate resistance in a Lolium rigidum population (DAG1) from South Africa. Nucleotide sequencing revealed the existence of at least three EPSPS homologues in the L. rigidum genome and identified a novel proline 106 to leucine substitution (P106L) in 52% DAG1 individuals. This mutation conferred a 1.7-fold resistance increase to glyphosate at the whole plant level. Additionally, a 3.1-fold resistance increase, not linked to metabolism or translocation, was estimated between wild-type P106-DAG1 and P106-STDS sensitive plants. Point accepted mutation analysis suggested that other amino acid substitutions at EPSPS position 106 are likely to be found in nature besides the P106/S/A/T/L point mutations reported to date. This study highlights the importance of minor mechanisms acting additively to confer significant levels of resistance to commercial field rates of glyphosate in weed populations subjected to high selection pressure.  相似文献   
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Community forestry has been characterized as a successful model of community-based forest governance in Nepal that shifts forest management and use rights to local users, often socially heterogeneous in caste, gender and wealth status. This heterogeneity forms the basis of social groups, which differ in their needs, priorities and perceptions regarding community forestry implementation processes. This paper explores the dynamics of three community forestry processes—users’ participation, institutional development, and decision-making and benefit-sharing—among forest user groups as perceived by three social groups of forest users—elite, women and disadvantaged—from eight community forests of Dhading district, Nepal, using qualitative and quantitative techniques. It is found that social groups have differing levels of perception about community forestry processes occurring in their user groups. In particular, social elites differ from women and disadvantaged members of the group in users’ participation in community forestry activities and institutional development of forest user groups. An important policy implication of the findings is that social inclusiveness is central to the effective implementation of community forestry processes, not only to safeguard its past successes but also to internalize the economic opportunities it poses through reducing deforestation and forest degradation in the future.  相似文献   
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Objective To devise a method for assessing evoked muscle strength on nerve stimulation [mechanomyography (MMG)] in the anaesthetized minipig. Study design Prospective observational. Animals Sixty male Göttingen minipigs weighing 10.5–26.0 kg. Methods After cadaveric studies, a limb fixation device was constructed which allowed the twitch responses of the pelvic limb digital extensor muscles to be measured by force‐displacement transduction in response to supramaximal train‐of‐four (TOF) stimulation of the common peroneal nerve. The device was tested in 60 minipigs weighing 10.5–26.0 kg positioned in dorsal recumbency. Results The technique recorded the MMG of the common peroneal–pelvic limb digital extensor nerve‐muscle unit for up to 12 hours during which twitch height remained constant in 18 animals in which single twitch duration was <300–500 ms. In 42, in which twitch duration was >300–500 ms, 2 Hz nerve stimulation caused progressive baseline elevation (reverse fade) necessitating a modified signal capture method for TOF ratio (TOFR) computation. However, T1 was unaffected. The mean (range) of the TOFR in pigs with reverse fade was 1.2 (1.1–1.3). Conclusions and clinical relevance The technique allowed MMG recording in unparalysed pigs in response to TOF nerve stimulation and revealed a hitherto unreported complication of MMG monitoring using TOF in animals: reverse fade. This complicated TOFR calculation.  相似文献   
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Clutton RE  Moens Y  Gasthuys F  Brodbelt D  Taylor P 《The Veterinary record》2007,160(5):171; author reply 171-171; author reply 172
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