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排序方式: 共有155条查询结果,搜索用时 15 毫秒
11.
WE Scherrer AE Kyles VF Samii EM Hardie PH Kass CR Gregory 《New Zealand veterinary journal》2013,61(6):330-333
AIMS: To assess the sensitivity of non-angiographic contrast-enhanced computed tomography (CT) to determine the presence of vascular invasion of cranial mediastinal masses in dogs and a cat, and to evaluate the association between vascular invasion and peri-operative mortality. METHODS: A retrospective study was conducted on 25 dogs and one cat. CT scans were completed with slices ranging from 2 to 10 mm. CT images were evaluated by a board-certifi ed radiologist blinded to previous diagnoses and surgical fi ndings. Each CT study was evaluated for vascular invasion, defi ned as disruption of the vessel wall and extension of the mass into the vessel lumen. Data retrieved from the surgery reports included surgical approach, whether vascular invasion was present, the surgeon's decision on operability, and post-operative complications. RESULTS: Computed tomographic evaluation revealed 25/26 masses had no evidence of vascular invasion. During surgical exploration, 10/26 masses were found to invade major regional vasculature; the cranial vena cava (CVC) was the vessel most commonly invaded (7/10 animals), and 4/7 (57%) patients with invasion of the CVC were euthanised or died in the perioperative period, from surgical or disease-related problems, which was signifi cantly higher than patients without vascular invasion (p=0.045). CONCLUSIONS: Non-angiographic contrast-enhanced CT was signifi cantly less sensitive for detecting vascular invasion of cranial mediastinal masses when compared with surgical evaluation. If the CVC was invaded by a tumour there was a signifi cant risk of death peri-operatively when compared with non-invasive cases. CLINICAL RELEVANCE: Due to the signifi cantly higher mortality risk associated with invasion of the CVC, a more sensitive method than CT should be investigated to determine vascular invasion of mediastinal masses pre-operatively. 相似文献
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13.
D. Alves Martins E. Gomes P. Rema J. Dias R.O.A. Ozório L.M.P. Valente 《Aquaculture International》2006,14(3):285-295
A shortage of marine raw ingredients, such as fish oil, is predicted in the near future. The use of suitable alternative lipid sources, such as vegetable oils, is crucial for sustainable growth of the aquaculture sector. Three isonitrogenous (50% Crude Protein) and isoenergetic (19 kJ g−1) diets, in which fish oil was gradually replaced by soybean oil (0, 25 and 50% of the oil fraction) were tested for 12 weeks, using European sea bass (Dicentrarchus labrax) and rainbow trout (Oncorhynchus mykiss) juveniles. No dietary effects (p>0.05) on growth performance, feed conversion, digestibility or body composition were observed with either species. The results obtained suggest the inclusion of soybean oil up to 50% of the dietary lipid is possible, in diets for sea bass and/or rainbow trout juveniles. 相似文献
14.
Definition of priority areas for forest conservation through the ordered weighted averaging method 总被引:2,自引:0,他引:2
Roberta de Oliveira Averna Valente Carlos Alberto Vettorazzi 《Forest Ecology and Management》2008,256(6):1408-1417
The general objective of this study was to evaluate the ordered weighted averaging (OWA) method, integrated to a geographic information systems (GIS), in the definition of priority areas for forest conservation in a Brazilian river basin, aiming at to increase the regional biodiversity. We demonstrated how one could obtain a range of alternatives by applying OWA, including the one obtained by the weighted linear combination method and, also the use of the analytic hierarchy process (AHP) to structure the decision problem and to assign the importance to each criterion. The criteria considered important to this study were: proximity to forest patches; proximity among forest patches with larger core area; proximity to surface water; distance from roads; distance from urban areas; and vulnerability to erosion. OWA requires two sets of criteria weights: the weights of relative criterion importance and the order weights. Thus, Participatory Technique was used to define the criteria set and the criterion importance (based in AHP). In order to obtain the second set of weights we considered the influence of each criterion, as well as the importance of each one, on this decision-making process. The sensitivity analysis indicated coherence among the criterion importance weights, the order weights, and the solution. According to this analysis, only the proximity to surface water criterion is not important to identify priority areas for forest conservation. Finally, we can highlight that the OWA method is flexible, easy to be implemented and, mainly, it facilitates a better understanding of the alternative land-use suitability patterns. 相似文献
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16.
Sandra Wenger Désirée Müllhaupt Stefanie Ohlerth Sarah Prasse Karina Klein Bianca da Silva Valente Martina Mosing 《Veterinary anaesthesia and analgesia》2017,44(3):529-537
Objective
To compare airway management during induction of anaesthesia, spontaneous ventilation (SV) and controlled mechanical ventilation (CMV), using an endotracheal tube (ETT), laryngeal mask (LM), rabbit-specific supraglottic airway device (v-gel) or facemask (FM).Study design
Prospective randomized crossover experiment.Animals
Ten New Zealand White rabbits.Methods
After premedication, rabbits were randomly allocated to four groups: 1) ETT; 2) LM; 3) v-gel or 4) FM. The required dose of propofol, duration and number of attempts to place an airway device and leakage during SV and CMV at different peak inspiratory pressures (6, 10, 12, 14 and 16 cmH2O) were recorded. Computed tomography (CT) of the head, neck and abdomen were performed before and after CMV.Results
Significantly less propofol and time [2.0 ± 0.5 mg kg?1, 82 ± 34 seconds, p < 0.001] were needed to place the FM compared to the three other groups [v-gel 5.1 ± 2.1 mg kg?1, 302 ± 124 seconds; LM 4.8 ± 1.2 mg kg?1, 275 ± 89 seconds; ETT 5.5 ± 1.4 mg kg?1, 315 ± 147 seconds]. A leak > 25% of the tidal volume occurred at the lowest pressure in FM [median (range), 6 (6–8) cmH2O], which was significantly lower than with v-gel [16 (6–no leak at 16) cmH2O], LM [>16 (6–no leak at 16)] or ETT [>16 (no leak at 16) cmH2O] (p < 0.001). On CT images, the height and width of the larynx were significantly smaller with v-gel in comparison to FM and LM (p = 0.004). A significant increase in the amount of gas in the stomach (p = 0.007), but not gastric volume, was detected in FM and LM.Conclusions and clinical relevance
The v-gel is a practical alternative to LM and ETT for airway management and CMV, but can compress the larynx. The FM is easily placed, but significant leakage occurs during CMV. 相似文献17.
The first records of the invasive pest Drosophila suzukii in the South American continent 总被引:1,自引:0,他引:1
Maríndia Deprá Jean Lucas Poppe Hermes José Schmitz Daniela Cristina De Toni Vera L. S. Valente 《Journal of pest science》2014,87(3):379-383
This paper presents the first report of the occurrence of Drosophila suzukii (Diptera: Drosophilidae) in South America. Several samples were collected during various seasons in 2012 and 2013, and a significant number of individuals were obtained and identified. Based on the data recorded during each sampling campaign, including the locality, temperature, time of year, and number of individuals collected, several conclusions were drawn about the development of this invasion in southern Brazil. 相似文献
18.
F.L. Pereira J.H.C. Gash J.S. David T.S. David P.R. Monteiro F. Valente 《Agricultural and Forest Meteorology》2009,149(3-4):680-688
In a previous study, it was shown that an isolated, fully saturated tree-crown behaves like a wet bulb, allowing evaporation of intercepted rainfall to be estimated by a simple diffusion equation for water vapour. This observation was taken as the basis for a new approach in modelling interception loss from savanna-type woodland, whereby the ecosystem evaporation is derived by scaling up the evaporation from individual trees, rather than by considering a homogeneous forest cover. Interception loss from isolated trees was estimated by combining the aforementioned equation for water vapour flux with Gash's analytical model. A new methodology, which avoids the subjectivity inherent in the Leyton method, was used for estimating the crown storage capacity. Modelling performance was evaluated against data from two Mediterranean savanna-type oak woodlands (montados) in southern Portugal. Interception loss estimates were in good agreement with observations in both sites. The proposed modelling approach is physically based, requires only a limited amount of data and should be suitable for the modelling of interception loss in isolated trees and savanna-type ecosystems. 相似文献
19.
de Lima Marllos Santos Araujo Maristela Machado Berghetti Álvaro Luís Pasquetti Aimi Suelen Carpenedo Costella Claudia Griebeler Adriana Maria Somavilla Luiza Michelon dos Santos Osmarino Pires dos Reis Teixeira Valente Brígida Maria 《New Forests》2022,53(1):161-179
New Forests - The forestry sector has been able to sustainably satisfy the increasing global demand for forest products, thereby positively impacting the economy, while mitigating climate change.... 相似文献
20.
Monilinia fructicola was until very recently a regulated pest in the European Union, and EU countries were requested to monitor its presence on their territories. As accredited laboratories should use validated tests, the mycological laboratory of CRA‐PAV carried out a validation process for the multiplex based PCR test (Coté et al., 2004 ), that is one of the most widely used tests for the identification of M. fructicola, although this test is not described in the EPPO diagnostic protocol PM 7/18 (2) because the validation data were lacking. The performance characteristics of this multiplex PCR test were established according to the EPPO Standard PM 7/98 (1) and the test was compared in a collaborative study with the end point PCR test (Ioos & Frey, 2000 ), considered as the ‘standard test’. The validation data were obtained using different isolates of M. fructicola, M. laxa, M. fructigena and Monilia polystroma, as well as different fruit tissues. Four series of the DNA target at different concentration, repeated three times, were analyzed in four Italian laboratories. The results showed that the multiplex PCR detection test (Coté et al., 2004 ) was fit for diagnostic purpose, although the analytical sensitivity was significantly lower compared to the conventional PCR ‘standard test’. 相似文献