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71.
McKenzie EC Jose-Cunilleras E Hinchcliff KW Holbrook TC Royer C Payton ME Williamson K Nelson S Willard MD Davis MS 《Journal of the American Veterinary Medical Association》2007,230(10):1486-1492
OBJECTIVE: To determine the impact of successive days of endurance exercise on select serum chemistry values in conditioned Alaskan sled dogs. DESIGN: Prospective cohort study. ANIMALS: 10 conditioned Alaskan sled dogs. PROCEDURES: All dogs ran 160 km/d for 5 consecutive days. Serum was obtained prior to exercise and immediately after each exercise run; all samples were obtained before dogs were fed. Serum electrolyte, mineral, protein, total bilirubin, urea nitrogen, creatinine, and cardiac troponin-I concentrations and serum alkaline phosphatase, alanine aminotransferase, creatine kinase, and aspartate aminotransferase activities were measured. Data were analyzed by means of analysis of covariance for a randomized complete block design with dog as a blocking variable, time as a covariate, and distance run as the treatment of interest. Least square mean values were compared with values obtained prior to exercise, and linear and quadratic contrasts were examined. RESULTS: Serum globulin concentration was low prior to exercise (mean +/- SD, 2.2 +/- 0.3g/dL) and progressively decreased as exercise continued. Exercise was associated with increases in serum chloride, urea nitrogen, and cardiac troponin-I concentrations and serum alanine aminotransferase, creatine kinase, and aspartate aminotransferase activities and with progressive decreases in serum potassium, total protein, and albumin concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that multiple successive days of endurance exercise resulted in mild aberrations in serum chemistry variables in conditioned sled dogs. Changes likely reflected the metabolic stresses of prolonged endurance exercise as well as dietary composition. Hypoglobulinemia in resting, conditioned sled dogs may reflect the immunosuppressive or catabolic effects of intense endurance training. 相似文献
72.
A simplified protocol to obtain fatty acid methyl esters (FAME) directly from fresh tissue, oils, or feedstuffs, without prior organic solvent extraction, is presented. With this protocol, FAME synthesis is conducted in the presence of up to 33% water. Wet tissues, or other samples, are permeabilized and hydrolyzed for 1.5 h at 55 degrees C in 1 N KOH in MeOH containing C13:0 as the internal standard. The KOH is neutralized, and the FFA are methylated by H(2)SO(4) catalysis for 1.5 h at 55 degrees C. Hexane is then added to the reaction tube, which is vortex-mixed and centrifuged. The hexane is pipetted into a gas chromatography vial for subsequent gas chromatography. All reactions are conducted in a single screw-cap Pyrex tube for convenience. The method meets many criteria for fatty acid analysis, including not isomerizing CLA or introducing fatty acid artifacts. It is applicable to fresh, frozen, or lyophilized tissue samples, in addition to oils, waxes, and feedstuffs. The method saves time and effort and is economical when compared with other methods. Its unique performance, including easy sample preparation, is achieved because water is included rather than eliminated in the FAME reaction mixtures. 相似文献
73.
中国水稻白叶枯病菌系染色体DNA的RFLP谱型的初析 总被引:5,自引:0,他引:5
用2个DNA探针pJEL101和pBASavrXa10对78个水稻白叶枯病菌系进行RFLP分型,以分析其群体结构和遗传多样性。分别鉴定出16种RFLP标记带的谱型。以彼此的带位相似率达85%为界,可分为簇。参试菌系的群体遗传多样性为0.77(用pJEL101),和0.83RFLP谱型分析表明:我国多数病原型为杂合组群。白叶枯病菌系的分子表现型的变异,远远大于致病型,两个探针都能有效分析我国菌系的群 相似文献
74.
Physical properties of field soil vary both spatially and temporally. Because so little information is available concerning the changes in magnitude of soil physical properties as functions of soil depth, distance normal to a crop row, and time, they have largely been ignored in model development. The purpose of this study was to evaluate quantitatively the spatial and temporal variability imposed by several tillage operations on several soil physical properties. Three tillage treatments, replicated 4 times in a randomized complete block design, were (1) conventionally-disked 3 times before planting, (2) full width strip chisel plowed to a 27-cm depth, and (3) in-row-subsoiled plus bedding. Soil physical properties measured were cone index (CI), weight percentage water (Pw), bulk density (Db), soil water characteristic curve, saturated hydraulic conductivity (Ksat) and soil settling. These properties were measured 3 times: immediately after planting soybeans (Glycine max (L.) Merr.) on 16 May; on 3 June; on 8 July 1977. Soil properties were measured at the 0–14, 14–28, and 28–41-cm soil depths at 3 positions relative to the row i.e., in the row, in the trafficked interrow, and in the non-trafficked interrow. Significant differences due to tillage treatment were found for Db, CI, and the soil water characteristic. The greatest spatial variation occurred in the 0–14-cm depth and decreased with depth. Significant differences for most variables were also found for the tillage by depth and tillage by position interactions. All properties exhibited significant temporal variation. 相似文献
75.
J H Gould S C Hight G H Alvarez C E Nelson S G Capar 《Journal of the Association of Official Analytical Chemists》1990,73(3):401-404
Use of lead glazes on ceramicware and the release of lead from finished glazes are reviewed. Single units of ceramicware with initial lead leach levels from less than 0.1 to 470 micrograms/mL were subjected to multiple automatic dishwashings with intermediate scrubbing of the ware by plastic fiber pads. Ware was periodically leached with 4% acetic acid solution at room temperature for 24 h, and the solutions were analyzed for lead. Release of lead under these conditions is discussed. Results indicated that neither passive leachings nor multiple dishwashings and scrubbings can predict future lead-release characteristics of glazes and decorations. 相似文献
76.
Campbell John L. Hornbeck James W. Mitchell Myron J. Adams Mary Beth Castro Mark S. Driscoll Charles T. Kahl Jeffrey S. Kochenderfer James N. Likens Gene E. Lynch James A. Murdoch Peter S. Nelson Sarah J. Shanley James B. 《Water, air, and soil pollution》2004,151(1-4):373-396
Input-output budgets for dissolved inorganic nitrogen (DIN) are summarized for 24 small watersheds at 15 locations in the northeasternUnited States. The study watersheds are completely forested, free of recent physical disturbances, and span a geographical region bounded by West Virginia on the south and west, and Maine on the north and east. Total N budgets are not presented; however, fluxes of inorganic N in precipitation and streamwater dominate inputs and outputs of N at these watersheds. The range in inputs of DIN in wet-only precipitation from nearby National Atmospheric Deposition Program (NADP) sites was 2.7 to 8.1 kg N ha-1 yr-1 (mean = 6.4 kg N ha-1 yr-1; median = 7.0 kg N ha-1 yr-1). Outputs of DIN in streamwater ranged from 0.1 to 5.7 kg N ha-1 yr-1 (mean = 2.0 kg N ha-1 yr-1; median = 1.7 kg N ha-1 yr-1). Precipitation inputs of DIN exceeded outputs in streamwater at all watersheds, with net retention of DIN ranging from 1.2 to 7.3 kg N ha-1 yr-1 (mean = 4.4 kg N ha-1 yr-1; median = 4.6 kg N ha-1 yr-1). Outputs of DIN in streamwater were predominantly NO3-N (mean = 89%; median = 94%). Wet deposition of DIN was not significantly related to DIN outputs in streamwater for these watersheds. Watershed characteristics such as hydrology, vegetation type, and land-use history affect DIN losses and may mask any relationship between inputs and outputs. Consequently, these factors need to be included in the development of indices and simulation models for predicting 'nitrogen saturation' and other ecological processes. 相似文献
77.
78.
Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献
79.
B Nelson 《Science (New York, N.Y.)》1967,156(781):1468-1469
80.
Basalts heated strongly with focused infrared laser radiation vaporized and splattered. Electron microprobe analyses of condensate, ejecta, and residue show strong vapor fractionation trends which, for some elements, are different from what would be expected theoretically and from previously reported data on more siliceous materials. It appears that solution effects can account for these differences. Heating of materials by a powerful focused laser beam for the purpose of study of vapor fractionation is a convenient technique that is more versatile than previous methods such as heating in solar or arc image furnaces. 相似文献