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排序方式: 共有358条查询结果,搜索用时 15 毫秒
271.
272.
A novel analytical procedure based on the combination of multiplex PCR, restriction analysis, and CGE-LIF to unambiguosly and simultaneously confirm the presence of multiple lines of genetically modified corn is proposed. This methodology is based on the amplification of event-specific DNA regions by multiplex PCR using 6-FAM-labeled primers. Subsequently, PCR products are digested by a mixture containing specific restriction endonucleases. Thus, restriction endonucleases selectively recognize DNA target sequences contained in the PCR products and cleave the double-stranded DNA at a given cleavage site. Next, the restriction digest is analyzed by CGE-LIF corroborating the length of the expected restriction fragments, confirming (or not) the existence of GMOs. For accurate size determination of the DNA fragments by CGE-LIF a special standard DNA mixture was produced in this laboratory for calibration. The suitability of this mixture for size determination of labeled DNA fragments is also demonstrated. The usefulness of the proposed methodology is demonstrated through the simultaneous detection and confirmatory analysis of samples containing 0.5% of GA21 and MON863 maize plus an endogenous gene of maize as control. 相似文献
273.
Ian D. Jones Virginia Luis Fuentes Adrian Boswood Melanie J. Hezzell David Wrigglesworth Ana Mateus Walasinee Moonarmart Jonathan Elliott 《Journal of Veterinary Cardiology》2012,14(1):203-210
ObjectivesTo measure flow-mediated vasodilation (FMD) in healthy dogs and in client-owned dogs with chronic valvular disease (CVD) and to investigate possible correlations between markers of CVD severity and FMD.AnimalsTwelve dogs with CVD and 11 healthy weight-matched dogs.MethodsBrachial artery FMD following 5 min inflation of a cuff around the antebrachium was measured in 12 dogs with CVD and 11 healthy weight-matched dogs. Measurements were also obtained in the healthy dogs 5 min after cuff placement but without inflation (‘sham cuff placement’). Dogs with CVD underwent echocardiography to confirm and characterize their disease.ResultsIn healthy dogs (median age 4 [2–6] years), median FMD was 7.7% versus 3.4% with sham cuff placement (P = 0.003). In dogs with CVD (median age 8 [4–16] years) median FMD was 5.5% versus 7.7% in healthy dogs (P = 0.131). FMD showed an inverse correlation with left ventricular end-diastolic diameter normalized for body weight (r = ?0.76, P = 0.0043).ConclusionsBrachial FMD in dogs with early CVD inversely correlates with severity of left ventricular remodelling. 相似文献
274.
Lorena A. Aguayo‐Ulloa Maria Pascual‐Alonso Csar Gonzlez‐Lagos Genaro C. Miranda‐de la Lama Morris Villarroel Begoa Asenjo Virginia Resconi Gustavo A. María 《Journal of animal physiology and animal nutrition》2019,103(6):1747-1757
The aim was to evaluate the effect of size (long or chopped wheat straw), type (barley or wheat) and presence/absence (1 week) of straw supplementation on behaviour and welfare of fattening lambs. Sixteen lambs (65 days) were individually housed to be used in two simultaneous experiments (8 lambs each) for 5 weeks of fattening. After a habituation period, they were offered straw that differed either in size (Experiment 1) or type (Experiment 2), which was followed by a week without straw and then reallocation of straw. Maintenance behaviours, play and stereotypies were analysed using video recording. Physiological stress responses were measured using blood samples taken at the end of the week without straw and after the reallocation of the straw. A preference test was performed during the last week. Concentrate and roughage consumption, average daily gain and conversion index were estimated. Lambs provided with long straw spent more time eating forage, playing and performed fewer stereotypies (Experiment 1). Lambs given wheat straw increased their play behaviour compared with those given barley straw, without affecting stereotypies (Experiment 2). When the straw was removed, lambs performed more behaviours associated with stress; however, this was not reflected in blood stress indicators. Lambs clearly preferred long straw over chopped straw, but no clear preference was observed between wheat and barley straw. The amount of forage intake was consistent with the time spent eating forage, but the amount of concentrate intake did not vary with eating concentrate behaviour, since the amount of concentrate intake was higher when the straw was removed, especially in Experiment 2. Our results show that size more than type of straw supplement impact the behaviour of lambs. Long straw reduces the stereotypies and increases play. This may improve the welfare and performance of fattening lambs, adding ethical value to a highly appreciated product. 相似文献
275.
Predicting across scales: Theory development and testing 总被引:21,自引:0,他引:21
Landscape ecologists deal with processes that occur at a variety of temporal and spatial scales. The ability to make predictions at more than one level of resolution requires identification of the processes of interest and parameters that affect this process at different scales, the development of rules to translate information across scales, and the ability to test these predictions at the relevant spatial and temporal scales. This paper synthesizes discussions from a workshop on Predicting Across Scales: Theory Development and Testing that was held to discuss current research on scaling and to identify key research issues. 相似文献
276.
Virginia Luis Fuentes 《Veterinary Clinics of North America: Small Animal Practice》2004,34(5):1145-1155
Pimobendan is an oral inodilator compound available in many countries for use in canine heart failure. It combines calcium-sensitizing effects with PDE III inhibition, resulting in positive inotropic effects and veno- and ergic signal transduction pathway in the failing heart, the calcium-sensitizing effects may assume greater importance in patients with heart failure. Clinical studies in human patients have shown sustained improvement in hemodynamics and exercise tolerance, with favorable neurohormonal effects. One study showed a nonsignificant trend toward increased mortality [20], but proarrhythmic effects have not ben observed. Studies in naturally occurring canine heart failure suggest that pimobendan's effects are at least comparable to those of ACE inhibitors, if not superior. Pimobendan is likely to play an increasing role in the future in the treatment of canine heart disease. 相似文献
277.
278.
279.
Koplitz SL Meurs KM Spier AW Bonagura JD Fuentes VL Wright NA 《Journal of the American Veterinary Medical Association》2003,222(6):770-774
OBJECTIVE: To determine aortic ejection velocity in healthy adult Boxers with soft ejection murmurs without overt structural evidence of left ventricular outflow tract obstruction and in healthy Boxers without cardiac murmurs. DESIGN: Retrospective study. ANIMALS: 201 Boxers. PROCEDURE: Dogs were examined independently by 2 individuals for evidence of a cardiac murmur, and a murmur grade was assigned. Maximal instantaneous (peak) aortic ejection velocity was measured by means of continuous-wave Doppler echocardiography from a subcostal location. Forty-eight dogs were reexamined approximately 1 year later. RESULTS: A soft (grade 1, 2, or 3) left-basilar ejection murmur was detected in 113 (56%) dogs. Overall median aortic ejection velocity was 1.91 m/s (range, 1.31 to 4.02 m/s). Dogs with murmurs had significantly higher aortic ejection velocities than did those without murmurs (median, 2.11 and 1.72 m/s, respectively). Auscultation of a murmur was 87% sensitive and 66% specific for the identification of aortic ejection velocity > 2.0 m/s. An ejection murmur and aortic ejection velocity > 2.0 m/s were identified in 73 (36%) dogs. For most dogs, observed changes in murmur grade and aortic ejection velocity during a follow-up examination 1 year later were not clinically important. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ejection murmurs were common among healthy adult Boxers and that Boxers with murmurs were likely to have high (> 2.0 m/s) aortic ejection velocities. The cause of the murmurs in these dogs is unknown. 相似文献
280.
Eleonora Deschamps Virginia S. T. Ciminelli Frank Thomas Lange J?rg Matschullat Brigitte Raue Hanka Schmidt 《Journal of Soils and Sediments》2004,4(3):169
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median
concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and
to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil
and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential
effects and how they compare with current screening and threshold values. While surface soil As-val-ues are reproducible at
a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrologicai variances.
Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential
health risk. 相似文献