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61.
Objectives – To (1) determine the occurrence of spurious hypercreatininemia in a population of hospitalized foals <2 days old, (2) assess the resolution of the hypercreatininemia, and (3) determine its association with survival in these foals. Design – Retrospective case series. Setting – 2 Referral hospitals. Animals – Foals <2 days old with an admission creatinine >442 μmol/L (>5.0 mg/dL) from 2 referral hospitals. Interventions – None. Measurements and Main Results – The medical records of 33 foals were reviewed. Twenty‐eight had spurious hypercreatininemia and 5 had acute renal failure. Admission creatinine was not significantly different between the 2 groups (mean [standard deviation]). The creatinine was 1,202 μmol/L (663 μmol/L) (13.6 mg/dL [7.5 mg/dL]) versus 1,185 μmol/L (787 μmol/L) (13.4 mg/dL [8.9 mg/d]) (P=0.96) in each group, respectively, though BUN at the time of hospital admission was significantly higher for acute renal failure foals (P=0.009). In the spurious group, serum creatinine at admission decreased to 504 μmol/L (380 μmol/L) (5.7 mg/dL [4.3 mg/dL]) by 24 hours, and to 159 μmol/L (80 μmol/L) (1.8 mg/dL [0.9 mg/dL]) at 48 hours, and to 115 μmol/L (44 μmol/L) (1.3 mg/dL [0.5 mg/dL]) at 72 hours. Twenty‐three of 28 foals with spurious hypercreatininemia survived to hospital discharge and there was no difference in mean admission creatinine between survivors (1176 μmol/L [628 μmol/L]) (13.3 mg/dL [7.1 mg/dL]) and nonsurvivors (1308 μmol/L [857 μmol/L]) (14.8 mg/dL [9.7 mg/dL]) (P=0.67). Twenty of 28 foals had clinical signs suggestive of neonatal encephalopathy. Conclusion – Creatinine decreased by >50% within the initial 24 hours of standard neonatal therapy and was within the reference interval in all but 1 foal within 72 hours of hospitalization. The diagnosis of neonatal encephalopathy was common in these foals.  相似文献   
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The survival of BradyrMzobium japonicum strains in autoclaved and non-autoclaved soil at various temperatures for up to 18 days was determined by plate count, plant infectivity-most probable number (MPN) and modified fluorescent antibody (FA) techniques. The high-temperature tolerant strains studied were BR587, NC1005 and NC1033, and the high-temperature intolerant strains studied were NCI028, 3Ilb24 and 311b123. Each strain was exposed individually in a sandy loam soil at 28, 33 or 37°C under humidity controlled conditions. Those strains reported to be tolerant to elevated temperature in pure culture decreased by <101.5 cells g−1 when enumerated by plate count after high-temperature exposure in autoclaved soil. Based on plate counts, the population of two of the three high-temperature intolerant strains added to autoclaved soil decreased by more than 103 cells g−1 soil after exposure to elevated temperatures. In non-autoclaved soil, the population of all inoculated strains decreased after exposure to elevated temperature when enumeration was by the plant infectivity-MPN technique. In autoclaved soil at 28°C, the correlation between plate count and FA enumerations was significant at the 0.05 probability level for four of the six strains (r2 = 0.65). After high-temperature incubation, counts based on the FA technique were not correlated with plate counts of intolerant strains or MPN enumeration of tolerant and intolerant strains (r2 = 0.004). Differential survival of B. japonicum strains in autoclaved soil at high temperature as enumerated by plate counts confirms the designation of temperature tolerance made by Munevar and Wollum (1981). However. MPN enumeration of bradyrhizobia in the non-autoclaved system did not follow the original temperature tolerance classifications. Enumeration by FA procedures did not show a decrease in population after exposure to high temperature as observed with the plate and MPN counts. Thus, the FA technique may not adequately indicate population dynamics in short-term ecological studies.  相似文献   
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Desmopathy of the distal interphalangeal joint collateral ligament is a common cause of lameness in the horse and carries a variable prognosis for soundness. Intralesional treatment has been proposed for improving outcome; however, limited reports describe methods for injecting this ligament. The purpose of this study was to compare accuracy of low‐field magnetic resonance imaging (MRI) vs. radiography for injecting the collateral ligament of the distal interphalangeal joint. Equine cadaver digit pairs (n = 10) were divided by random assignment to injection of the ligament by either technique. An observer unaware of injection technique determined injection success based on postinjection MRI and/or gross sections acquired from the proximal, middle, and distal portions of the ligament. McNemar's test was performed to determine statistical difference between injection techniques, the number of injection attempts, and injection of the medial or lateral collateral ligament. Magnetic resonance imaging guided injection was successful more frequently than radiographic‐guided injection based on postinjection MRI (24 of 30 vs. 9 of 30; P = 0.0006) and gross sections (26 of 30 vs. 13 of 30; P = 0.0008). At each level of the ligament (proximal, middle, and distal), MRI‐guided injection resulted in more successful injections than radiographic guidance. Statistical significance occurred at the proximal aspect of the collateral ligament based on postinjection MRI (P = 0.0143) and the middle portion of the ligament based on gross sections (P = 0.0253). Findings supported future testing of standing, low‐field MRI as a technique for delivering intralesional regenerative therapy in live horses with desmopathy of these collateral ligaments.  相似文献   
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Summary Ten potato cultivars were rated for a leaf spotting disorder at three locations in Maine in each of two years; there were consistent differences between cultivars and between locations. Cultivar Seminole had no symptoms but cultivar Plymouth had severe symptoms in both years. A comparison of preliminary data of soil analyses and leaf spotting scores for the three locations showed that higher levels of the disorder were associated with higher levels of phosphorous and lower levels of aluminum and iron. The effects of nitrogen and other elements on leaf spotting could not be discounted.
Zusammenfassung Zehn Kartoffelsorten wurden an drei Standorten in Maine in jeweils zwei Jahren hinsichtlich der H?he des Schadens durch Blattflecken untersucht. Zwischen den Sorten (Tabellen 1 und 2) und den Standorten (Tabellen 2, 3 und 4) wurden gleichbleibende Unterschiede bei der Blattfleckung gefunden. Die Unterschiede drückten sich von ‘frei von Blattflecken’ bei der Sorte ‘Seminole’ bis zu 80% Flecken bei der Sorte ‘Plymouth’ aus (Tabelle 1). Diese Blattfleckung unterscheidet sich von der Sch?digung durch Luftverschmutzung durch die Entwicklung von Symptomen zuerst auf der Blattoberfl?che (Hooker et al., 1973). Bodenanalysen bei den drei verschiedenen Standorten zeigten, dass der Standort mit der h?chsten Blattfleckung den h?chsten Gehalt an Phosphor und den niedrigsten Gehalt an Eisen und Aluminium aufwies (Tabellen 3 und 4). Obwohl die Einflüsse anderer Elemente nicht ausgeschlossen werden konnten, ist anzunehmen, dass die Einflüsse von Eisen-, Aluminium-und Phosphorgehalten auf die ?tiologie dieser Krankheit die aussichtsreichsten Gebiete für weitere Untersuchungen sind.

Résumé Dix variétés de pommes de terre sont classées quant à l'expression d'anomalies foliaires en taches, dans trois localités pendant deux années, dans le Maine. Des différences conséquentes sont observées entre les variétés (tableaux 1 et 2) et entre les localités (tableaux 2, 3, et 4). Les différences varient de: aucune tache pour la variété ‘Seminole’ à 80% de taches pour ‘Plymouth’ (tableau 1). Les anomalies foliaires en taches sont distinguées des lésions dues à la pollution atmosphérique par l'apparition primaire des sympt?mes sur la face inférieure des feuilles (Hooker et al., 1973). Les analyses de sol des trois localités montrent que les sympt?mes les plus marqués sont observés dans la localité ayant les plus hauts niveaux de phosphore et les plus faibles de fer et d'aluminium (tableaux 3 et 4). Bien que les effets des autres éléments ne puissent pas être écartés, il semble que les meilleures voies de recherches futures soient les effets des niveaux d'aluminium, de fer et de phosphore sur l'étiologie de cette anomalie.
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The previous larval-trajectory modeling studies on Georges Bank were assessed through process-oriented Lagrangian-tracking comparison experiments using the high-resolution Gulf of Maine/Georges Bank Finite-Volume Coastal Ocean Model (GOM-FVCOM). The results indicate that in a strong nonlinear system such as Georges Bank, the passive tracer movement is driven by a fully three-dimensional Lagrangian flow field that varies in space and time due to large tidal excursion and steep bottom topography. The particle-tracking methods developed based on the assumption of weak nonlinearity of the flow field are not applicable to Georges Bank. The results of previous larval transport studies driven by circulation fields constructed under the weak-nonlinearity assumption need to be interpreted with caution. In the present work, the influence of model physical setups on sea scallop larval dispersal and settlement on Georges Bank and adjacent shelf regions is examined. Distinct differences in the spatial distribution of the passive larvae predicted by the model under various physical conditions suggest that a fully nonlinear model driven by realistic spatially and temporally varying forcing should be employed for Lagrangian-based studies of fishery population dynamics on Georges Bank.  相似文献   
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Soil tillage practices can affect soil hydraulic properties and processes dynamically in space and time with consequent and coupled effects on chemical movement and plant growth. This literature review addresses the quantitative effects of soil tillage and associated management (e.g., crop residues) on the temporal and spatial variability of soil hydraulic properties. Our review includes incidental management effects, such as soil compaction, and natural sources of variability, such as topography. Despite limited research on space–time predictions, many studies have addressed management effects on soil hydraulic properties and processes relevant to improved understanding of the sources of variability and their interactions in space and time. Whether examined explicitly or implicitly, the literature includes studies of interactions between treatments, such as tillage and residue management. No-tillage (NT) treatments have been compared with various tillage practices under a range of conditions with mixed results. The trend, if any, is for NT to increase macropore connectivity while generating inconsistent responses in total porosity and soil bulk density compared with conventional tillage practices. This corresponds to a general increase in ponded or near-zero tension infiltration rates and saturated hydraulic conductivities. Similarly, controlled equipment traffic may have significant effects on soil compaction and related hydraulic properties on some soils, but on others, landscape and temporal variability overwhelm wheel-track effects. Spatial and temporal variability often overshadows specific management effects, and several authors have recognized this in their analyses and interpretations. Differences in temporal variability depend on spatial locations between rows, within fields at different landscape positions, and between sites with different climates and dominant soil types. Most tillage practices have pronounced effects on soil hydraulic properties immediately following tillage application, but these effects can diminish rapidly. Long-term effects on the order of a decade or more can appear less pronounced and are sometimes impossible to distinguish from natural and unaccounted management-induced variability. New standards for experimental classification are essential for isolating and subsequently generalizing space–time responses. Accordingly, enhanced methods of field measurement and data collection combined with explicit spatio-temporal modeling and parameter estimation should provide quantitative predictions of soil hydraulic behavior due to tillage and related agricultural management.  相似文献   
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