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991.
992.
K. KuKanich B. KuKanich A. Harris E. Heinrich 《Journal of veterinary pharmacology and therapeutics》2014,37(5):451-456
Sucralfate and minocycline may be administered concurrently to dogs. The relative bioavailability of tetracyclines may be reduced if administered with sucralfate, but studies confirming these interactions in dogs are not available. This study evaluated the pharmacokinetics of oral minocycline in dogs (M), determined the effects of concurrent administration of sucralfate and minocycline (MS) on minocycline pharmacokinetics, determined the effects of delaying sucralfate administration by 2 h (MS+2) on minocycline pharmacokinetics, and established dosing recommendations based on pharmacodynamic indices. Oral minocycline (300 mg) and sucralfate suspension (1 g) were administered to five greyhounds in a randomized crossover design. Minocycline plasma concentrations were evaluated using liquid chromatography with mass spectrometry. The maximum plasma concentration (CMAX) and area under the curve (AUC) of minocycline were 1.15 μg/mL and 8.0 h* μg/mL, respectively. The CMAX and AUC were significantly lower (P < 0.05) in the MS group (CMAX = 0.33 μg/mL, AUC 3.0 h*μg/mL) compared with M or MS+2 (CMAX = 0.97 μg/mL, AUC 10.3 h*μg/mL). Delaying sucralfate by 2 h did not decrease oral minocycline absorption, but concurrent administration significantly decreased minocycline absorption. A dose of 7.5 mg/kg p.o. q12 h achieves the pharmacodynamic index for a bacterial minimum inhibitory concentration (MIC) of 0.25 μg/mL (AUC:MIC≥33.9). 相似文献
993.
A. Vernunft P. Harris E. Kienzle 《Journal of animal physiology and animal nutrition》2014,98(2):246-250
Based on a series of exercise tests which included the estimation of sweat losses, this article proposes a novel sweat scoring system for exercising horses. This provides a practical estimate of individual animal exercise‐induced sweat losses, based on visible appearance of sweat on the coat after work, which takes into account the effect of various influencing factors. In terms of accuracy and flexibility, the score seems to provide advantages over estimates based on current general recommendations from reference books. Additional studies are needed to validate this scoring system and its use under more diverse situations. 相似文献
994.
Betzig E Trautman JK Harris TD Weiner JS Kostelak RL 《Science (New York, N.Y.)》1991,251(5000):1468-1470
In near-field scanning optical microscopy, a light source or detector with dimensions less than the wavelength (lambda) is placed in close proximity (lambda/50) to a sample to generate images with resolution better than the diffraction limit. A near-field probe has been developed that yields a resolution of approximately 12 nm ( approximately lambda/43) and signals approximately 10(4)- to 10(6)-fold larger than those reported previously. In addition, image contrast is demonstrated to be highly polarization dependent. With these probes, near-field microscopy appears poised to fulfill its promise by combining the power of optical characterization methods with nanometric spatial resolution. 相似文献
995.
Effect of light chain V region duplication on IgG oligomerization and in vivo efficacy 总被引:1,自引:0,他引:1
W Shuford H V Raff J W Finley J Esselstyn L J Harris 《Science (New York, N.Y.)》1991,252(5006):724-727
A human immunoglobulin G1 (IgG1) antibody oligomer was isolated from a transfected myeloma cell line that produced a monoclonal antibody to group B streptococci. Compared to the IgG1 monomer, the oligomer was significantly more effective at protecting neonatal rats from infection in vivo. The oligomer was also shown to cross the placenta and to be stable in neonatal rats. Immunochemical analysis and complementary DNA sequencing showed that the transfected cell line produced two distinct kappa light chains: a normal light chain (Ln) with a molecular mass of 25 kilodaltons and a 37-kilodalton species (L37), the domain composition of which was variable-variable-constant (V-V-C). Cotransfection of vectors encoding the heavy chain and L37 resulted in production of oligomeric IgG. 相似文献
996.
Laurie F. Caslake Skye S. Harris Christine Williams Nancy McCreary Waters 《Water, air, and soil pollution》2006,174(1-4):93-105
Although Onondaga Lake in the Syracuse NY area is contaminated with high levels of mercury from past manufacturing operations, macrophytes in the lake have been able to survive, apparently withstanding mercury toxicity. Homogenates of three macrophyte species, Myriophyllum spicatum L., Potamogeton crispus L., and Stuckenia pectinata (L.) Borner, were phenotypically positive for the presence of mercury resistant bacteria. As determined by PCR analysis, the mercury resistant bacteria associated with M. spicatum and S. pectinata also possessed merA, one of the more widely studied essential genes in the mer operon. Analysis of 24 macrophyte taxa isolated from lakes across the United States, as well as biological supply houses, showed that mercury resistant bacteria were associated with all macrophytes. One possible explanation for the association of mercury resistant bacteria with macrophytes is described. This hypothesis suggests that Hg r bacteria may potentially ameliorate the negative effects that mercury elicits in macrophytes. 相似文献
997.
A single-chain anti-atrazine antibody fragment, scAb (single-chain Fv with a CK domain), was expressed in Escherichia coli, and monomeric and dimeric species were preferentially purified from periplasmic extracts by chromatography upon nickel chelate immunosorbent columns or by immunoaffinity purification using a constant domain (CK) tag. Recombinant monomeric and dimeric antibody fragments, Fab, and intact monoclonal antibodies were compared in assays by competition between free atrazine in solution and (a) immobilized atrazine-bovine serum albumin conjugate (indirect assay) or (b) atrazine-alkaline phosphatase (direct assay). Recombinant antibody fragments provided a lower detection limit than either Fab or intact monoclonal antibody in both assay formats. Monomeric fragments displayed a sensitivity of detection down to 0.1 ppb, compared to 1.0 ppb for dimeric fragments and the parental monoclonal. 相似文献
998.
Numerous methods to analyze biogenic amines in biological materials have been described. A versatile and rapid methodology to analyze these compounds in feedstuffs, complete feeds, and animal tissues, however, has not been reported. The current method was developed to address this need. Biogenic amines in feedstuffs, complete animal feeds, and animal tissues were extracted with 10% trichloroacetic acid, reacted with O-phthaladehyde using high-performance liquid chromatographic employing a cation exchange column. Detection limits were 50 pmol/mL for tyramine, histamine, putrescine, and spermine; 40 pmol/mL for cadaverine; and 25 pmol/mL for spermidine. Extraction efficiency of biogenic amines in feedstuffs, duodenum, liver, ileum + jejunum, and whole shrimp and shrimp hepatopancreas ranged between 99-105, 93-135, 80-85, 65-102, 88-98, and 88-97%, respectively. It can be concluded that the current method can be applied to individual feedstuffs, complete feeds, and animal tissues for the rapid and accurate determination of concentration of biogenic amines. 相似文献
999.
1000.
Kees-Jan van Groenigen Antonie Gorissen Dave Harris Jan Willem van Groenigen 《Soil biology & biochemistry》2005,37(3):497-506
The net flux of soil C is determined by the balance between soil C input and microbial decomposition, both of which might be altered under prolonged elevated atmospheric CO2. In this study, we determined the effect of elevated CO2 on decomposition of grass root material (Lolium perenne L.). 14C-labeled root material, produced under ambient (35 Pa pCO2) or elevated CO2 (70 Pa pCO2) was incubated in soil for 64 days. The soils were taken from a pasture ecosystem which had been exposed to ambient (35 Pa pCO2) or elevated CO2 (60 Pa pCO2) under FACE-conditions for 10 years and two fertilizer N rates: 140 and 560 kg N ha−1 year−1. In soil exposed to elevated CO2, decomposition rates of root material grown at either ambient or elevated CO2 were always lower than in the control soil exposed to ambient CO2, demonstrating a change in microbial activity. In the soil that received the high rate of N fertilizer, decomposition of root material grown at elevated CO2 decreased by approximately 17% after incubation for 64 days compared to root material grown at ambient CO2. The amount of 14CO2 respired per amount of 14C incorporated in the microbial biomass (q14CO2) was significantly lower when roots were grown under high CO2 compared to roots grown under low CO2. We hypothesize that this decrease is the result of a shift in the microbial community, causing an increase in metabolic efficiency. Soils exposed to elevated CO2 tended to respire more native SOC, both with and without the addition of the root material, probably resulting from a higher C supply to the soil during the 10 years of treatment with elevated CO2. The results show the importance of using soils adapted to elevated CO2 in studies of decomposition of roots grown under elevated CO2. Our results further suggest that negative priming effects may obscure CO2 data in incubation experiments with unlabeled substrates. From the results obtained, we conclude that a slower turnover of root material grown in an ‘elevated-CO2 world’ may result in a limited net increase in C storage in ryegrass swards. 相似文献