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381.
Coakley M Peck KE Taylor TS Matthews NS Mealey KL 《American journal of veterinary research》1999,60(11):1441-1444
OBJECTIVE: To compare serum disposition of flunixin meglumine after i.v. administration of a bolus to horses, donkeys, and mules. ANIMALS: 3 clinically normal horses, 5 clinically normal donkeys, and 5 clinically normal mules. PROCEDURE: Blood samples were collected at time zero (before) and 5, 10, 15, 30, and 45 minutes, and at 1, 1.25, 1.5, 1.75, 2, 2.5, 2.75, 3, 3.5, 4, 4.5, 5, 5.5, 6, and 8 hours after i.v. administration of a bolus of flunixin meglumine (1.1 mg/kg of body weight). Serum was analyzed in duplicate by the use of high-performance liquid chromatography for determination of flunixin meglumine concentrations. The serum concentration-time curve for each horse, donkey, and mule were analyzed separately to estimate noncompartmental pharmacokinetic variables RESULTS: Mean (+/-SD) area under the curve for donkeys (646 +/- 148 minute x microg/ml) was significantly less than for horses (976 +/- 168 minute x microg/ml) or for mules (860 +/- 343 minute x microg/ml). Mean residence time for donkeys (54.6 +/- 7 minutes) was significantly less than for horses (110 +/- 24 minutes) or for mules (93 +/- 30 minutes). Mean total body clearance for donkeys (1.78 +/- 0.5 ml/kg/h) was significantly different from that for horses (1.14 +/- 0.18 ml/kg/h) but not from that for mules (1.4 +/- 0.5 ml/kg/h). Significant differences were not found between horses and mules for any pharmacokinetic variable. CONCLUSION AND CLINICAL RELEVANCE: Significant differences exist with regard to serum disposition of flunixin meglumine in donkeys, compared with that for horses and mules. Consequently, flunixin meglumine dosing regimens used in horses may be inappropriate for use in donkeys. 相似文献
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Gill disorders have emerged in recent years as a significant problem in the production of marine‐stage Atlantic salmon Salmo salar L. The multi‐aetiological condition ‘proliferative gill inflammation’ (PGI) has been reported to cause heavy losses in western Norway, yet reports of Scottish cases of the disease have remained anecdotal. In the present study, histopathological material from a marine production site in the Scottish Highlands experiencing mortalities due to a seasonal gill disease with proliferative‐type pathology was examined using light microscopy, special staining techniques and transmission electron microscopy (TEM). The microsporidian Desmozoon lepeophtherii Freeman et Sommerville, 2009 (syn. Paranucleospora theridion) was identified by staining using a Gram Twort method and TEM associated with distinctive proliferative and necrotic pathology confined to the interlamellar Malpighian cell areas of the primary filaments. Epitheliocystis was not a feature of the gill pathology observed. It is believed this is the first report of D. lepeophtherii being identified associated with pathology in a Scottish gill disease case, and supports anecdotal reports that a disease at least partly synonymous with PGI as described by Norwegian researchers is present in Scottish aquaculture. 相似文献
384.
Benchmark study on glyphosate‐resistant cropping systems in the United States. Part 7: Effects of weed management strategy (grower practices versus academic recommendations) on the weed soil seedbank over 6 years
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Electron transmission experiments demonstrate a large asymmetry in the scattering probability of polarized electrons by thin organized films of chiral molecules. This large asymmetry results from the interaction of the electron's wavefunction with many scatterers (molecules) in the organized monolayer structure and represents a manifestation of quantum interference on the scale of supramolecular lengths. 相似文献
387.
Glutamate is a central metabolite for whole-animal energy and N metabolism. This study tested the hypothesis that ileal epithelium, liver, and kidney content of system X-(AG) glutamate transporters EAAC1 and GLT-1 would be up-regulated to support growth of wethers (30 +/- 1.2 kg) fed a forage-based diet for at least 14 d to gain (2.0 x NEm; n = 9) vs. maintain (1.2 x NEm; n = 9) BW. We have previously demonstrated that two high-affinity glutamate transporters (EAAC1, GLT-1) are expressed by these extensive glutamate metabolizing epithelial tissues. Wethers fed at 2.0 x NEm gained (P < 0.001; 0.26 kg/d) BW, whereas those fed 1.2 x NEm did not. Although plasma concentrations (microM) of glucose and L- or D-glutamate did not differ, plasma glutamine (precursor of glutamate) and alanine concentrations (transamination product of glutamate) were 28% (P < 0.007) and 22% (P < 0.072) greater for growing lambs than nongrowing lambs. In tissues, the concentration of L-glutamate in ileum epithelia and D-glutamate of liver was 49% (P < 0.015) and 181% (P < 0.042) greater, respectively, in growing vs. nongrowing animals, whereas concentrations of glutamate isoforms did not differ in kidney. Paralleling these increased amino acid concentrations, ileal epithelium contained 313% more (P < 0.038) EAAC1 protein and liver contained 240% more (P < 0.001) GLT-1 protein, whereas kidney transporter content did not differ between growing and nongrowing wethers. In contrast to increased EAAC1 and GLT-1 protein content in ileal and liver tissue of growing lambs, messenger RNA levels did not differ. These results indicate that the increased capacity for high-affinity glutamate uptake in growing vs. nongrowing lambs is achieved through increased expression of EAAC1 by ileal epithelium and GLT1 by liver, which parallel increased tissue concentrations of glutamate and plasma concentrations of two major interorgan N carriers, glutamine and alanine. 相似文献
388.
389.
J D Jacobson M W Miller N S Matthews S M Hartsfield K W Knauer 《American journal of veterinary research》1992,53(4):537-540
The accuracy of a pulse oximeter was evaluated over a wide range of arterial oxygen and carbon dioxide tensions, using 2 probes (finger probe and ear probe) and 2 monitoring sites (tongue and tail) in anesthetized dogs. The arterial oxygen saturation of hemoglobin (SaO2) measured directly with a multiwavelength spectrophotometer was compared with saturation estimated by pulse oximetry (SpO2). Linear regression analysis of the pooled data from 399 simultaneous measurements of SpO2 and SaO2 indicated a highly significant correlation of SpO2 with SaO2 (r = 0.97; P less than or equal to 0.0001). Although the mean difference (+/- SD) between SpO2 and SaO2 for pooled data was small (-0.06 +/- 6.8%), SpO2 tended to underestimate high SaO2 values (greater than or equal to 70%) and to overestimate low SaO2 values (less than 70%). When SaO2 values were greater than or equal to 70%, the ear probe applied to the tail was less accurate (produced a significantly greater SpO2-SaO2 difference) than the ear probe on the tongue, or the finger probe at either site. When SaO2 values were less than or equal to 50%, the finger probe applied at the tail was more accurate (produced significantly smaller SpO2-SaO2 differences) than the ear probe at either site. When SaO2 values were less than or equal to 70%, high arterial carbon dioxide tension (greater than or equal to 60 mm of Hg) was associated with greater overestimation of SaO2. 相似文献
390.
H K Matthews E Hunt D E Duncan 《Journal of the American Veterinary Medical Association》1992,200(5):699-701
Ventral edema, dyspnea, fever, tachycardia, bloat and muffled heart sounds were identified in a 3-year-old heifer. Attempts to relieve the bloat by passing an orogastric tube were unsuccessful. The heifer was bovine leukemia virus-negative by the agar gel immunodiffusion test, and had normocytic, normochromic anemia, mature neutrophilia, and hyperproteinemia. Pleural effusion was identified by thoracic ultrasonography. Cytologic examination of pleural fluid revealed an increased number of atypical lymphocytes. The heifer died, and at necropsy, thymic and metastatic mammary lymphosarcoma was confirmed. 相似文献