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排序方式: 共有140条查询结果,搜索用时 15 毫秒
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Ivanka Krasteva Anne Liljander Anne Fischer David G.E. Smith Neil F. Inglis Massimo Scacchia Attilio Pini Joerg Jores Flavio Sacchini 《Veterinary microbiology》2014
Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides (Mmm) is a severe cattle disease, present in many countries in sub-Saharan Africa. The development of improved diagnostic tests and vaccines for CBPP control remains a research priority. Polyacrylamide gel electrophoresis and mass spectrometry were used to characterize the Triton X-114 soluble proteome of nine Mmm strains isolated from Europe or Africa. Of a total of 250 proteins detected, 67 were present in all strains investigated. Of these, 44 were predicted to be lipoproteins or cytoplasmic membrane-associated proteins and are thus likely to be members of the core in vitro surface membrane-associated proteome of Mmm. Moreover, the presence of all identified proteins in other ruminant Mycoplasma pathogens were investigated. Two proteins of the core proteome were identified only in other cattle pathogens of the genus Mycoplasma pointing towards a role in host–pathogen interactions. The data generated will facilitate the identification and prioritization of candidate Mycoplasma antigens for improved control measures, as it is likely that surface-exposed membrane proteins will include those that are involved in host–pathogen interactions. 相似文献
44.
Olcott AN Sessions AL Corsetti FA Kaufman AJ de Oliviera TF 《Science (New York, N.Y.)》2005,310(5747):471-474
Laterally extensive black shales were deposited on the S?o Francisco craton in southeastern Brazil during low-latitude Neoproterozoic glaciation approximately 740 to 700 million years ago. These rocks contain up to 3.0 weight % organic carbon, which we interpret as representing the preserved record of abundant marine primary productivity from glacial times. Extractable biomarkers reflect a complex and productive microbial ecosystem, including both phototrophic bacteria and eukaryotes, living in a stratified ocean with thin or absent sea ice, oxic surface waters, and euxinic conditions within the photic zone. Such an environment provides important constraints for parts of the "Snowball Earth" hypothesis. 相似文献
45.
Alatalo RV Aragón S Avilés JM Barbosa A Gomes CB Cadée N Christe P Cuervo JJ Díaz M Erritzøe J Galeotti P Garamszegi LZ Gil D Gontard-Danek M Legendre S Martin TE Martínez J Martín-Vivaldi M Martínez JG Merino S Moreno J Mousseau T Ninni P Petrie M Pulido F Rubolini D Saino N Soler JJ Soler M Spottiswoode C Szép T Thornhill R Zamora C Sacchi R 《Science (New York, N.Y.)》2004,303(5664):1612
46.
R. Aragüés 《Irrigation Science》1982,3(2):133-147
Summary The stability of 22 commercially available soil salinity sensors was studied: 23% were considered to be stable under the imposed experimental conditions during a period of 14 months. During the same time period, accuracy of sensors decreased from ±0.32 to ±0.98 mmho cm–1. Time response is adequate under saturated conditions (Fig. 3) but it may be extremely long for unsaturated soils (Fig. 4 and Table 2). Measurements of the soil solution electrical conductivity with salinity sensors and by the suction probe extraction technique demonstrated that the soil matrix affects the salt distribution near soil surfaces and within the pore space. Time response (63% of total change) of sensor thermistor is 0.9 min, with an estimated accuracy of ±0.3 °C. 相似文献
47.
Robson Andreazza Simone Pieniz Amauri A. Barcelos Maurizio S. Quadro Flavio A. O. Camargo 《Journal of plant nutrition》2015,38(10):1580-1594
Phytoremediation is a helpful technique to remediate copper-contaminated areas. The aim of this study was to evaluate sunflower phytoremediation capacity in two vineyard copper-contaminated soils (Inceptisol and Mollisol) and a copper mining waste. Nutrient uptake, copper phytoaccumulation, translocation factor (TF), and bioaccumulation factor (BCF) of sunflower were evaluated after 57 days of growth. Plants grown in both the Mollisol and Inceptisol soils showed high plant height. Fresh biomass was high in the Mollisol in the shoots and roots and also demonstrated the highest values on the tolerance index (TI). The BCF after growth in all three of the copper contaminated soils as Inceptisol, Mollisol, and copper mining waste showed reduction of this index value to 0.19, 0.24, and 0.03, respectively against native soil (Mollisol under natural conditions (4.71). Sunflowers have some important characteristics such as high phytomass production, copper phytoaccumulation, and potential use to biofuel. Thus, sunflower is a potential candidate to phytoremediation of vineyard copper-contaminated soils. 相似文献
48.
An integrative approach for analysing landscape dynamics in diverse cultivated and natural mountain areas 总被引:3,自引:1,他引:2
Our landscape can be regarded as a development process that is affected and subsequently shaped by a series of different environmental
and human-induced factors. However, to date, concrete data about the impact of each of these factors are still missing. One
key reason for this is that methods of acquisition and evaluation of these factors inherently have differences, thereby preventing
meaningful comparative analyses. This study presents an integrative methodical approach that bridges many of these gaps. Our
approach also has the advantages of being generally applicable while delivering easily interpretable results that also allow
comparisons between diverse geographical regions. The indicators used enable all major features of landscape change, e.g.
changes in land use, landscape structuring, habitat settings, and urban sprawl, to be accurately monitored and provide high-quality
realistic results that were validated in our study site, South Tyrol (North Italy). Indicators were selected for both their
further subdivision, e.g. monocrops and different features of mixed crops, and their easy to ascertain hierarchically structured
feature classification, e.g. land cover. Furthermore, our use of ecoregions enables better comparison of aspects of landscape
development for geographical regions having diverse socio-economic and ecological conditions. Our methodical approach can
be used as a basis not only for creating landscape change scenarios, but also for determining the environmental and human-induced
factors involved and being able to list them in order of importance. Further the detected striking difference between the
mapped land-use data and the official census data suggests a validation of the methodical approach in context of the national
agriculture census. 相似文献
49.
Emily H. Berryhill Naomi S. Urbina Sam Marton William Vernau Flavio H. Alonso 《Journal of veterinary diagnostic investigation》2023,35(2):124
The Wellness Ready Test (WRT) is a lateral flow, stall-side assay that measures equine insulin in whole blood and requires validation before recommending clinical use. We evaluated intra- and inter-assay precision and linearity and compared the WRT with a radioimmunoassay (RIA). Tested concentrations ranged from <139 to >695 pmol/L (<20 to >100 μIU/mL). For 20 replicates at each insulin level, intra-assay CVs of the WRT for insulin were 13.3%, 12.9%, and 15.3% at low (139–278 pmol/L; 20–40 μIU/mL), intermediate (278–417 pmol/L; 40–60 μIU/mL), and high (>417 >60 μIU/mL) concentrations, respectively. For 10 replicates at each level (3 assay lots), inter-assay CVs were 15.9%, 11.0%, and 11.7%, respectively. In the weighted linear regression of 5 measured insulin concentrations against expected concentrations, R2 = 0.98, slope = 1.02, and y-intercept = 14.4 pmol/L (2.08 μIU/mL). The Spearman correlation coefficient (rs) was 0.90 (95% CI: 0.85–0.94) between the WRT and RIA; the WRT = f(RIA) Passing–Bablok regression yielded the fit, y = 1.005x + 24.3 pmol/L (3.50 μIU/mL). The WRT result averaged 10.4% higher than the RIA result, with targeted bias of 25.9, 26.1, and 26.7 pmol/L (3.74, 3.76, and 3.84 μIU/mL) for cutoffs used to diagnose insulin dysregulation of 312, 347, and 451 pmol/L (45, 50, and 65 μIU/mL). Assay clinical sensitivities, specificities, and accuracies determined at the 3 selected clinical cutoffs and using the RIA as gold standard were 87–95%, 92–96%, and 91–95%, respectively (n = 99 samples). Observed total error was 28.4–30.4%. The WRT had acceptable precision, excellent linearity, and good association with the RIA. 相似文献
50.
Stelio P. L. Luna Polly M. Taylor & Flavio Massone 《Journal of veterinary pharmacology and therapeutics》1997,20(2):153-159
Six Welsh gelding ponies were premedicated with 0.03 mg/kg of acepromazine intravenously (i.v.) prior to induction of anaesthesia with midazolam at 0.2 mg/kg and ketamine at 2 mg/kg i.v.. Anaesthesia was maintained for 2 h using 1.2 % halothane concentration in oxygen. Heart rate, electrocardiograph (ECG), arterial blood pressure, respiratory rate, blood gases, temperature, haematocrit, plasma arginine vasopressin (AVP), dynorphin, ß-endorphin, adrenocorticotropic hormone (ACTH), cortisol, dopamine, noradrenaline, adrenaline, glucose and lactate concentrations were measured before and after premedication, immediately after induction, every 20 min during anaesthesia, and at 20 and 120 min after disconnection. Induction was rapid, excitement-free and good muscle relaxation was observed. There were no changes in heart and respiratory rates. Decrease in temperature, hyperoxia and respiratory acidosis developed during anaes-thesia and slight hypotension was observed (minimum value 76 ± 10 mm Hg at 40 mins). No changes were observed in dynorphin, ß-endorphin, ACTH, catecholamines and glucose. Plasma cortisol concentration increased from 220 ± 17 basal to 354 ± 22 nmol/L at 120 min during anaesthesia; plasma AVP concentration increased from 3 ± 1 basal to 346 ± 64 pmol/L at 100 min during anaesthesia and plasma lactate concentration increased from 1.22 ± 0.08 basal to 1.76 ± 0.13 mmol/L at 80 min during anaesthesia. Recovery was rapid and uneventful with ponies taking 46 ± 6 min to stand. When midazolam/ketamine was compared with thiopentone or detomidine/ketamine for induction before halothane anaesthesia using an otherwise similar protocol in the same ponies, it caused slightly more respiratory depression, but less hypotension. Additionally, midazolam reduced the hormonal stress response commonly observed during halothane anaesthesia and appears to have a good potential for use in horses. 相似文献