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21.
Diego E. Gomez Nicola C. Cribb Luis G. Arroyo André Desrochers Gilles Fecteau Sylvain Nichols 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(10):965-969
Endoscopic removal of esophageal and ruminal foreign bodies was successfully performed in 5 Holstein-Friesian calves under sedation or general anesthesia by using an electrocautery snare or a wire-guided Dormi basket. This report describes the endoscopic manipulations, treatment, and outcomes of esophageal foreign body removal in these calves. 相似文献
22.
Nicola J Grint Thierry Beths Kathy Yvorchuk Polly M Taylor Mike Dixon Helen R Whay Joanna C Murrell 《Veterinary anaesthesia and analgesia》2014,41(4):421-429
ObjectiveTo evaluate a mechanical nociceptive threshold (MNT) testing device in the donkey, and to investigate the influence of potential confounders on MNTs generated.Study designProspective, randomised.AnimalsSixteen castrated male donkeys aged 4–9 years, weighing 105–170 kg.MethodsMechanical nociceptive thresholds were measured using an actuator with three pins placed on the dorsal aspect of the distal limb, connected to a force meter. The pins (surface area 15 mm2) were extruded onto the limb by pressurising an air-filled syringe, until the MNT force (when foot-lift was observed) or 25 N (cut-off force) was reached. Effect on MNT of presence of a companion donkey, the limb tested, rate of application of force, testing location, level of distraction, ambient temperature and hair cover at the test site was evaluated. Long and short-term repeatability of MNT was assessed. Data were analysed using general linear models and Mann–Whitney U tests, p < 0.05 was considered significant.ResultsIncreasing the rate of force application significantly increased the mean ± SD MNT from 9.2 ± 2.0 N when applied at 0.4 N sec?1 to 10.6 ± 2.1 N when applied at 1.2 N sec?1 (p = 0.001). No other factors significantly influenced MNT. Mean MNT remained stable over a 3 week period, however MNTs were significantly (p = 0.006) higher (12.8 ± 3.0 N cf 10.3 ± 1.9 N) after a 12 month interval.Conclusions and clinical relevanceWhen designing studies measuring MNT in donkeys, rate of application of force must be standardised. Donkeys’ MNTs have good short-term stability suggesting this technique is appropriate for short-term analgesiometry studies; however variability of MNTs over the long-term is greater. 相似文献
23.
Nicola Skert Jari Falomo Luigi Giorgini Alessandro Acquavita Lorenzo Capriglia Roberto Grahonja Nordio Miani 《Water, air, and soil pollution》2010,206(1-4):95-103
In order to find out a new effective accumulator of polycyclic aromatic hydrocarbons (PAHs) useful for monitoring studies on a large scale and low costs, the accumulation capacity of both biological and artificial matrixes (mosses and polyester fibers, respectively) has been tested. For this purposes, Hypnum cupressiforme and dacron® were exposed to pollution airborne in two sites located nearby an active iron industry and in center of the town of Trieste, where high PAH pollution spots, due to vehicular traffic, are usually detected. The samplers were exposed in six sampling sessions for 21 days. The results obtained were compared with data collected by active PAH samplers, usually employed for official widespread monitoring. The level of correlation between the data sets was calculated. Furthermore, a repeatability study of data was performed. According to the results, both matrixes are good PAH accumulators, though they show different skills. 相似文献
24.
25.
Lacetera N Franci O Scalia D Bernabucci U Ronchi B Nardone A 《American journal of veterinary research》2002,63(3):414-418
OBJECTIVE: To assess the effects of nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (BHBA) on functions of mononuclear cells obtained from ewes. ANIMALS: 6 Sardinian ewes. PROCEDURE: Mononuclear cells were cultured with concentrations of NEFA (0, 15.6, 31.2, 62.5, 125, 250, 500, 1,000, or 2,000 micromol/L) and BHBA (0, 0.45, 0.9, 1.8, or 3.6 mmol/L). Concentrations of NEFA and BHBA were intended to mimic those of ketotic or healthy ewes, and NEFA and BHBA were tested alone and in combination. Synthesis of DNA was stimulated by use of concanavalin A (Con A) or pokeweed-mitogen (PWM). Secretion of IgM was stimulated by use of PWM. RESULTS: Synthesis of DNA stimulated by Con A and PWM was significantly inhibited by high concentrations of NEFA (> or = 250 micromol/L) or by a combination of high concentrations of NEFA (> or = 250 micromol/L) and all concentrations of BHBA (> or = 0.45 mmol/L). In contrast, DNA synthesis was not inhibited by low concentrations of NEFA (< or = 125 micromol/L) or by a combination of low concentrations of NEFA (< or = 125 micromol/L) and the lowest concentration of BHBA (0.45 mmol/L). Secretion of IgM was significantly inhibited by all concentrations of NEFA and by all combinations of NEFA and BHBA concentrations. When used alone, none of the concentrations of BHBA inhibited DNA synthesis or IgM secretion. CONCLUSIONS AND CLINICAL RELEVANCE: Reduced immunoresponsiveness during ketosis is likely to be associated with an increase in plasma concentration of NEFA and not with an increase in plasma concentration of BH BA. 相似文献
26.
Valeria Negri Nicola Tosti Mario Falcinelli Fabio Veronesi 《Genetic Resources and Crop Evolution》2000,47(2):141-146
Thirteen landraces of cowpea (Vigna unguiculata (L.) Walp. subsp. unguiculata cv. gr. Unguiculata) have been morphologically and agronomically characterised as part of a plan for safeguarding and protecting plant biodiversity typical of Lake Trasimeno (Umbria, central Italy). Sixty plants per accession were scored for plant vigour, growth habit, flower colour, days to flowering, days to first mature pod, pod length, total number of pods produced, seed colour pattern, 100 seed weight, total seed yield and virus susceptibility. With the exception of vigour and growth habit, all landraces appeared to be well differentiated from one another for all the characters considered. Strategies and problems related to their in situ conservation are discussed. 相似文献
27.
High protein content and a strong gluten are required in durum wheat (Triticum turgidum L. var. durum) to process semolina into a suitable final pasta product. The variation in grain protein content and quality realized through breeding and the concomitant variation in biomass production and partitioning have been analyzed by comparing in a 2-year field trial, four groups of cultivars released in different eras and areas of breeding. Three groups of cultivars represented the evolution of the Italian germplasm from the first landraces and genealogical selections (Group 1) to the cultivars constituted by crossing Mediterranean types with Syriacum types (Group 2), and the modern dwarf and semi-dwarf cultivars (Group 3). Group 4 was an ICARDA collection of breeding lines bred for adaptation to high altitudes. The measured traits included both biomass production and its partitioning to the grain, and total nitrogen uptake and its partitioning to the grain. Grain protein percentage, gluten content and gluten index were utilized as quality traits. Breeding resulted in an increased earliness, reduced height without significant decreases in total biomass, and improved partitioning. The concomitant total nitrogen uptake did not change, whereas the changed biomass partitioning caused a parallel change in nitrogen partitioning, with an increase in nitrogen harvest index from 0.41 to 0.59. The lower protein percentage in the grains of modern cultivars was therefore not due to a reduced nitrogen uptake, nor to a lower NHI or to less milligram of nitrogen per grain, but to the dilution effect caused by the heavier grains of modern cultivars. A notable increase in gluten index was observed in the modern cultivars, reflecting an improvement in the pasta-making quality of grain proteins. 相似文献
28.
Upscaling of agro-ecological indicators applied in regional analyses is sensitive to scale issues of the input data. This study develops a methodology to quantify this sensitivity for an indicator of soil organic carbon (SOC) dynamics at the farming system level. A reference case consists of seven fully described farms in northern Italy. Both upscaling in complexity by substituting measured input with estimated input and upscaling in space by extending the methods to farms not included in the reference case are addressed. The indicator increased with 3-107% at four farms after substituting measured management input with that estimated by an expert, whereas it remained unchanged or decreased at the other three farms. Taking the modal value from a cluster of pedological input did not lead to additional uncertainty in most cases, and only slightly increased it in others. We evaluated spatial upscaling by including 733 farms divided in 18 clusters that were described with less information as compared to the reference farms. Within each cluster, we observed relevant variability of the indicator (coefficients of variation of 12-43%), as a consequence of the heterogeneity of farms comprised in each cluster. In each cluster we calculated the indicator for one virtual farm, defined by using modal values for basic farm inputs. In this case the indicator was highly correlated (R2 = 0.98) with the average of the values obtained using measured basic farm inputs. We conclude that upscaling in complexity and space introduces uncertainty in the values of the indicator compared to the reference case. The extent of such differences depends on the variability of the systems under analysis and on indicator sensitivity. 相似文献
29.
Romanowsky AJ Douglas NG Arnaboldi M Kuijken K Merrifield MR Napolitano NR Capaccioli M Freeman KC 《Science (New York, N.Y.)》2003,301(5640):1696-1698
The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies were studied with the Planetary Nebula Spectrograph. The galaxies' velocity-dispersion profiles were found to decline with the radius, and dynamical modeling of the data indicates the presence of little if any dark matter in these galaxies' halos. This unexpected result conflicts with findings in other galaxy types and poses a challenge to current galaxy formation theories. 相似文献
30.
Discussions of the evolution of intelligence have focused on monkeys and apes because of their close evolutionary relationship to humans. Other large-brained social animals, such as corvids, also understand their physical and social worlds. Here we review recent studies of tool manufacture, mental time travel, and social cognition in corvids, and suggest that complex cognition depends on a "tool kit" consisting of causal reasoning, flexibility, imagination, and prospection. Because corvids and apes share these cognitive tools, we argue that complex cognitive abilities evolved multiple times in distantly related species with vastly different brain structures in order to solve similar socioecological problems. 相似文献