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81.
In this study, the pharmacokinetics of moxifloxacin (5 mg/kg) was determined following a single intravenous administration of moxifloxacin alone and co-administration with diclofenac (2.5 mg/kg) or flunixin meglumine (2.2 mg/kg) in sheep. Six healthy Akkaraman sheep (2 ± 0.3 years and 53.5 ± 5 kg of body weight) were used. A longitudinal design with a 15-day washout period was used in three periods. In the first period, moxifloxacin was administered by an intravenous (IV) injection. In the second and third periods, moxifloxacin was co-administered with IV administration of diclofenac and flunixin meglumine, respectively. The plasma concentration of moxifloxacin was assayed by high-performance liquid chromatography. The pharmacokinetic parameters were calculated using a two-compartment open pharmacokinetic model. Following IV administration of moxifloxacin alone, the mean elimination half-life (t1/2β), total body clearance (ClT), volume of distribution at steady state (Vdss) and area under the curve (AUC) of moxifloxacin were 2.27 hr, 0.56 L h−1 kg−1, 1.66 L/kg and 8.91 hr*µg/ml, respectively. While diclofenac and flunixin meglumine significantly increased the t1/2β and AUC of moxifloxacin, they significantly reduced the ClT and Vdss. These results suggest that anti-inflammatory drugs could increase the therapeutic efficacy of moxifloxacin by altering its pharmacokinetics.  相似文献   
82.
In this study, blood serum and leukocyte samples were collected from 400 Holstein heifers, all of which appeared to be healthy. Antibodies (Ab) against bovine viral diarrhea virus (BVDV) were detected in 57 serum samples, and BVDV antigen (Ag) was detected in 38 leukocyte samples. There were statistically important differences between the average first insemination ages (FIT) of the BVDV (Ag-/Ab+) heifers (p<0.0001) (pregnant p<0.05, nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers. The average conception rates (CR) of BVDV (Ag-/Ab+) heifers and BVDV (Ag-/Ab-) heifers were not significant statistically. There were statistically important differences in average FIT between persistent infected (PI) BVDV (Ag+/Ab-) heifers (p<0.0001; PI pregnant p<0.05, PI nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers. No significant differences in average CR between PI BVDV (Ag+/Ab-) heifers and BVDV (Ag-/Ab-) heifers were found. The differences in average FIT between BVDV (Ag+/Ab+; p<0.0001; nonpregnant p<0.0001) and BVDV (Ag-/Ab-) heifers were important statistically. Although there were no BVDV (Ag+/Ab+) pregnant heifers, the differences in average CR between BVDV (Ag+/Ab+) pregnant heifers and BVDV (Ag-/Ab-) heifers were found to be statistically important (p<0.0001). We conclude that fertility is affected in heifers with BVDV (Ag-/Ab+, Ag+/Ab- and Ag+/Ab+).  相似文献   
83.
The objective of this study was to determine the effects of stocking density on the activity of glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD) and glutathione reductase (GR) enzymes in liver, muscle, gill and kidney tissues of rainbow trout. Fish were reared at different stocking densities (15 kg/m3, 20 kg/m3, 25 kg/m3 and 30 kg/m3). After adaptation period of 30 days, the experiment was carried out for two months. Stocking density of the control group was 15 kg/m3. Increasing stocking density caused inhibition in the activities of the enzymes except for kidney G6PD and 6PGD. Activity of both pentose phosphate pathway enzymes unexpectedly increased only in kidney whereas inhibition was observed in other tissues. Since the most powerful and gradual attenuation was observed in muscle tissue for all enzymes, we performed quantitative Real Time PCR to examine the expression of heat shock protein (Hsp70) gene in muscle in order to understand whether the decrease in enzyme activities is associated with stress. The mRNA expression data showed that Hsp70 expression levels significantly elevated at 25 kg/m3 and 30 kg/m3 stocking densities. Overall results indicate that increasing stocking density blocks the activity of metabolic and antioxidant enzymes and causes considerable stress in rainbow trout. The most susceptible tissue to increasing stocking density was observed to be the muscle.  相似文献   
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85.
Here we investigated the in vitro and in vivo effects of the pesticides, deltamethrin, diazinon, propoxur and cypermethrin, on the activity of rainbow trout (rt) gill carbonic anhydrase (CA). The enzyme was purified from rainbow trout gills using Sepharose 4B-aniline-sulfanilamide affinity chromatography method. The overall purification was approx. 214-fold. SDS-polyacrylamide gel electrophoresis showed a single band corresponding to a molecular weight of approx. 29 kDa. The four pesticides dose-dependently inhibited in vitro CA activity. IC50 values for deltamethrin, diazinon, propoxur and cypermethrin were 0.137, 0.267, 0.420 and 0.460 μM, respectively. In vitro results showed that pesticides inhibit rtCA activity with rank order of deltamethrin > diazinon > propoxur > cypermethrin. Besides, in vivo studies of deltamethrin were performed on CA activity of rainbow trout gill. rtCA was significantly inhibited at three concentrations (0.25, 1.0 and 2.5 μg/L) at 24 and 48 h.  相似文献   
86.
87.
Use of reduced and no-tillage systems has increased in recent years due to concerns for ecological and economic sustainability of agricultural production. Effective weed control is a serious concern in reduced tillage production. This study was conducted to investigate weed control practices in reduced and no-till maize production. The most effective timing of glyphosate application, either before or after sowing, was investigated in combination with pre-emergence application of acetochlor (840 g a.i/L), post-emergence application of foramsulfuron (22.5 g a.i/L), and two hoeing treatments. The treatments were maintained on the same plots during 2011 and 2012 to evaluate the cumulative effects of the treatments. Main plot treatments consisted of four timings of glyphosate application: 20 or 10 days before sowing, day of sowing, 5 days after sowing, and an untreated control. Sub-plot treatments were: pre- plus post-emergence herbicides, pre-emergence herbicide plus rotary hoeing, post-emergence herbicide plus rotary hoeing, and post-emergence herbicide plus two hoeing treatments (rotary and lister hoe). In the main plots, the lowest weed biomass was produced in glyphosate treatments at sowing and 5 days after sowing; the highest biomass was produced in control plots and in the plots with glyphosate treatments 20 days before sowing. In the sub-plots, the greatest weed biomass was produced in plots with two hoeing treatments (rotary and lister hoe). Glyphosate treatments at sowing and post-emergence herbicide treatment combinations produced the best weed control. Economic analysis revealed that pre-sowing, non-selective herbicide treatments provided a slight increase in net profit. Mechanical hoeing decreased net income due to increased production costs. The highest income was obtained from the pre-emergence plus post-emergence herbicide treatment combinations with no glyphosate.  相似文献   
88.
In this study, chemical composition of berries of 10 sea buckthorn (Hippophae rhamnoides L.) genotypes in Turkey was investigated. The total phenolic content of the berries ranged from 21.31 mg gallic acid equivalents (GAE) per g dry weight basis to 55.38 mg GAE per g. The highest antioxidant activity was 93.54% (similar to the standard BHT at 200 mg/L) and the lowest was 80.38%. There was no correlation (R = 0.688) between the total phenolic content and the antioxidant activity. The major fatty acids in berries were palmitoleic acid (35.48%), followed by palmitic acid (28.13%), oleic acid (22.89%) and linoleic acid (3.96%). Total soluble solid content of sea buckthorn genotypes varied from 10.15 to 14.80%, titratable acidity varied from 2.64 to 4.54%, the pH varied from 2.63 to 2.98 and Vitamin C varied from 19 to 121 mg/100 mL. The average content of minerals in the sea buckthorn berries of different genotypes was 20,800 ppm N, 7100 ppm P, 7260 ppm K, 1960 ppm Ca, 1465 ppm Mg, 32 ppm Zn, 24 ppm Cu, 22 ppm Mn and 7 ppm Fe.  相似文献   
89.
Over the last two decades, the demand for organic products has grown rapidly in the world due to increased concern about side effects of pesticides on the environment and human health. Studies were conducted in organic lettuce (Lactuca sativa L.) from 2004 to 2005 at the Black Sea Agricultural Research Institute in Samsun, Turkey, to determine the suppressive effects of summer cover crops on weeds. The experiment was arranged in a randomized complete block design with four replications. Treatments consisted of grain sorghum [Sorghum bicolor (L.) Moench.], sudangrass [Sorghum vulgare Pers. var. sudanense (Piper) Hitchc.], hairy vetch (Vicia villosa Roth.), grain amaranth (Amaranthus cruentus L.), pea (Pisum sativum L.) and bare ground with no cover crop. Weed density and total weed dry biomass were assessed before and at 14, 28, and 56 days after incorporation (DAI) of the cover crops. The cover crops produced between 1.2 and 3 t ha−1 biomass and grain sorghum produced more dry matter than any other species in both years. After incorporation of the cover crops, hairy vetch and sorghum treatments showed fewer weed species, and lower weed density than the other cover crops in both years. Hairy vetch, grain sorghum, and sudangrass were the most effective cover crops and reduced total weed dry biomass by 90.3%, 87.4%, and 86.9% in 2004, and by 88%, 86.3%, and 85.2% in 2005, respectively. Cover crop residue suppressed many broadleaved weed species but failed to control grass weeds. Hairy vetch treatments produced the highest yield, followed by sudangrass and grain sorghum. Yields with grain amaranth and pea were similar to that of the control. These results indicate that hairy vetch, grain sorghum, and sudangrass can be used to suppress weeds in early season of organic lettuce production.  相似文献   
90.
Maize (Zea mays L.) landraces are considered to be important genetic resources for improving maize. To use these sources effectively, the extent of genetic diversity among them needs to be determined. While maize landraces from different countries have been evaluated, there is only limited information available on Turkish maize landraces. Thus, our objective was to investigate the genetic relations among 35 different landraces, along with inbred lines B73 and Mo17, using the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We also measured seven kernel-quality traits, viz., protein content, oil content, zein content, lysine content, tryptophan content, and amylose/amylopectin content. Cluster analysis was performed to classify the Turkish maize landraces relative to protein-band variation. Results of protein-band analyses showed there was significant diversity among maize landraces. There was also considerable variation for the kernel-quality traits of the landraces. Kernel oil varied from 2.83% to 6.27%, protein from 6.67% to 11.34%, zein from 1.87% to 8.88%, tryptophan from 0.017% to 0.053%, lysine from 0.14% to 0.81%, amylose from 5.9% 37.6%, and amylopectin from 62.4% to 94.1% among the landraces. A total of 25 protein subunits, with molecular weight ranging from 10 to 110 kDa, were determined, and all of them, except for three bands, were polymorphic. Polymorphism information content (PIC) of the subunits ranged between 0.00 and 0.50. Maize landraces were classified into two main clusters; the first cluster included 18 landraces and inbred lines B73 and Mo17, whereas the second cluster comprised 17 maize landraces. Overall, results revealed that Turkish maize landraces having similar geographical origins were classified in the same clusters and exhibited a high level of diversity relative to protein subunits.  相似文献   
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