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871.
High doses of dextromethorphan (DM) have been clinically investigated for the treatment of multiple neuronal disorders including neuropathic pain. Several authors have suggested the concomitant administration of DM and a CYP2D6 reversible inhibitor in order to enhance the exposure of DM and limit the exposure to total dextrorphan (DX). The present study proposes to determine whether or not a single dose of quinidine is sufficient to enhance the plasma concentrations of DM in rats and keep those of DX at a minimal level. Oral doses of DM (50 mg/kg) were administered with increasing dose levels of quinidine (0, 2, 20, and 50 mg/kg) to male Sprague-Dawley rats and blood samples were collected over 24 h. Plasma concentrations of DM and total DX were determined using ESI-LC/MS/MS. Quinidine coadministration resulted in a more than twofold increase in the area under the curve of DM with an ED(50) of approximately 2 mg/kg whereas those of total DX were only increased by 21%. These results support the working hypothesis that a single dose of quinidine may enhance the plasma concentrations of DM relative to those of total DX and may therefore improve the treatment of neuropathic pain.  相似文献   
872.
The effects of the antioxidant lipoic acid on beef longissimus bloom time   总被引:1,自引:0,他引:1  
The objective of this study was to evaluate the influence of lipoic acid (LA) on beef LM steak bloom time, as well-as to characterize bloom time in the CIE L*, a*, and b* color space over a 93-min period. Thirty-two Simmental steers were supplemented with LA for 21 d immediately before slaughter at levels of 0, 8, 16, or 24 mg of LA/kg BW (eight steers per treatment). Lipoic acid was mixed with liquid paraffin, allowed to solidify, prilled, and top-dressed over a standard finishing diet. Steers were slaughtered at the University of Missouri abattoir in four groups of eight (two steers per treatment) over a 2-wk period. After a 24-h chill at 4 degrees C, the right LM was removed from each carcass. One 2.54cm steak was removed from the anterior portion of the LM, and its color characteristics (CIE L*, a*, and b*) were measured immediately with a standardized spectrocolorimeter. Color measurements were taken every 3 min thereafter for a total of 93-min. Hue angle (true red) and chroma (color saturation) were calculated from the color measurements. Addition of LA to the diet had no effect on bloom time (P = 0.67). When treatment means were analyzed, the addition of 24 mg of LA/kg BW to the diet resulted in higher (lighter) L* values (P < 0.05) compared with other treatments, whereas the addition of 16 mg of LA/kg BW to the diet caused lower hue angles (more true red; P < 0.05) when compared with other treatments. Addition of LA to the diet did not affect a* (P = 0.13) and b* (P = 0.18) values or chroma (P = 0.62). In the absence of treatment effects, bloom times for all treatments were pooled, and L* values did not change (P > 0.05) during the 93-min bloom time; however, a* and chroma values increased for 9 min and plateaued after 12 min (P < 0.01). Similarly, b* values increased (P < 0.01) for the first 6 min, and after 9 min, no further increase in yellowness was detected. Bloom time had little effect on hue angle, which stabilized after 3 min. Supplementing steers with the antioxidant LA for 21 d had no effect on the bloom time of beef LM; however, higher levels of supplemental LA affected L* values and hue angles of beef.  相似文献   
873.
Following pretreatment with clindamycin, cleaning, scaling, polishing, and curettage, six beagles that were patients at the Dental Department of the Clinic for Surgery and Ophthalmology of the University of Veterinary Medicine of Vienna received a doxycycline polymer filling (Doxirobe, Pharmacia Animal Health) in periodontal pockets of teeth 204, 208, 304, and 309. Gingivitis index, gingival crevicular fluid, probing depth, and attachment loss were determined before and 6 and 12 weeks after treatment. Teeth 104, 108, 404, and 409 did not receive antibiotic therapy but were pretreated in the same manner as the doxycycline-treated teeth. Pocket depth for teeth treated with doxycycline was significantly reduced (improved) by 39% after 6 weeks (P =.001) and by 35% after 12 weeks (P =.001). Pockets around control teeth were improved after cleaning and curettage but were still significantly deeper than around teeth treated with doxycycline. Compared with control teeth, teeth treated with doxycycline had significantly less gingival crevicular fluid after treatment (P =.001). Teeth treated with doxycycline gained significant attachment after 6 (42%) and 12 (38%) weeks. Significantly fewer bacteria were harvested from doxycycline-treated teeth than from control teeth. The gingival index was significantly lower in the doxycycline-treated teeth than in the control teeth 6 (P =.002) and 12 (P =.007) weeks after treatment. Local application of doxycycline complements traditional subgingival curettage therapy in a reasonable and effective way and can significantly improve treatment success, especially with regard to pocket depth reduction and attachment gain.  相似文献   
874.
875.
876.
Development of body mass and the mass of thigh, back and loins musculature was examined at 4, 8, 10 and 12 weeks in 51 California hybrids and 49 New Zealand White hybrids. Body mass development was practically identical in these rabbits. Peak growth rate of the characteristics studied occurred at 2-3 months of age in the California hybrids, but at a variable time in the New Zealand White. Age was less important than body mass in the development of criteria of productivity.  相似文献   
877.
Ruminal mucosae of 15 pygmy goats of different age (Z1 approximately 4-5 months, Z2 approximately 1 year, Z3 approximately 1.5-5 years) and sex were investigated histologically. The thickness of the Stratum corneum of the 3 experimental groups was in the Atrium ruminis 23.0, 23.0 and 29.1 microns, in the Recessus ruminis ventralis 22.8, 28.0 and 30.0 microns, that of the Stratum germinativum and Stratum granulosum in the Atrium ruminis 74.8, 78.4 and 82.3 microns and in the Recessus ruminis ventralis 87.4, 84.7 and 87.7 microns, that of the Corpus papillare in the Atrium ruminis 75.3, 75.2 and 74.4 and in the Recessus ruminis ventralis 85.0, 78.9 and 71.6 microns. The cell nuclear volumes of the basal and parabasal cells of papillae originating from the Atrium ruminis (a) and the Recessus ruminis ventralis (b) in the individual experimental groups were in case of a 103.2; 100.2 and 117.3 microns3 resp. in case of b 93.4; 96.4 and 119.7 microns3.  相似文献   
878.
Chilo partellus is a major crop pest in Asia and Africa, and has recently spread to the Mediterranean region. Knowledge of its potential distribution can inform biosecurity policies aimed at limiting its further spread and efforts to reduce its impact in areas that are already invaded. Three models of the potential distribution of this insect have been published, each with significant shortcomings. We re-parameterized an existing CLIMEX model to address some parameter inconsistencies and to improve the fit to the known distribution of C. partellus. The resulting model fits the known distribution better than previous models, highlights additional risks in equatorial regions and reduces modelled risks in wet and extremely dry regions. We bring new insights into the role of irrigation in the potential spread of this invasive insect and compare its potential distribution with the present known distribution of its hosts. We also distinguish regions that are suitable for supporting persistent populations from those that may be at risk from ephemeral populations during favourable seasons. We present one of the first demonstrations of a new capability in CLIMEX to automatically estimate parameter sensitivity and model uncertainty. Our CLIMEX model highlights the substantial invasion risk posed by C. partellus to cropping regions in the Americas, Australia, China, Europe, New Zealand and West Africa. Its broad host range and reported impacts suggest that it should be a pest of significant concern to biosecurity agencies in these presently uninvaded regions.  相似文献   
879.
BACKGROUND: The ADVIA 120 is an automated laser cell counter widely used in veterinary medicine. Although specific software for equine samples is available and validated, only a few reports have been published comparing the ADVIA 120 with other methods for equine hemogram evaluation. OBJECTIVES: The purpose of this study was to compare the hematologic values and reference intervals obtained on the ADVIA 120 with those obtained on an impedance cell counter and manual differential counts in healthy horses. METHODS: EDTA-anticoagulated blood samples were obtained from 114 clinically healthy horses of various breeds, both sexes, and 2-6 years of age. Samples were stored for up to 12 hours at 4 degrees C and then analyzed on the ADVIA 120 and the Hemat 8. A 100-cell to 200-cell differential leukocyte count was performed by 3 independent observers on May-Grünwald-Giemsa-stained smears. Intra-assay precision of the ADVIA 120 was determined by analyzing 5 replicates each of 10 of the blood samples. RESULTS: Results from the ADVIA were significantly higher than those from the impedance counter for RBC count, total WBC count, hemoglobin concentration, red cell distribution width, MCH, and MCHC, and significantly lower for HCT and platelet count. Significantly higher neutrophil and basophil counts and significantly lower lymphocyte counts were obtained with the ADVIA 120 compared with manual counts. Based on Passing-Bablok regression analysis, RBC and platelet counts were in good agreement between the 2 analyzers; a constant and proportional bias was present for other values. Coefficients of variation for erythrocyte parameters on the ADVIA were <1%, but were higher for platelet (6%), total WBC (2%), differential WBC (4%-30%), and reticulocyte (75%) counts. CONCLUSIONS: Results obtained with equine samples on the ADVIA 120 were comparable with those obtained on an impedance counter; reference intervals differed statistically but overlapped. The ADVIA had poor precision for reticulocyte and differential leukocyte counts such that the latter should always be verified on smears.  相似文献   
880.
Elution of Cl?, SO4 2?, NO3 ?, and H+ often occurred in that order at a site in the central Sierra Nevada, California, that receives an annual average of 1000 cm of snowfall which is low in acidic components. During eight winter periods of above-base level snowpack outflow, and one spring melt period, on the average 25% of the ions were discharged at the following percentages of outflow volumes: Cl? at 11%, NO3 ? at 13%, SO4 2? at 18%, and H+ at 20%. Seven of eight winter outflows were associated with low ionic strength rainfall onto the snowpack. Mean solute concentrations during the first 25% and first 50% of the total outflow were significantly greater than during the last 75% and last 50% of the total outflow for Cl?, NO3 ?, and SO4 2?, but not for H+. Maximum solute concentrations were up to 2.9 times the overall event volume-weighted mean concentrations for Cl?, 3.7 times for NO3 ?, 3.0 times for SO4 2?, and 2.9 times for H+.  相似文献   
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