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1.
Adin DB Hill RC Scott KC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(5):724-726
Parenteral veterinary furosemide is a 50-mg/mL solution with a pH of 8.0-9.3. The purpose of this study was to determine whether a commonly used veterinary formulation of 50 mg/mL of furosemide solution could be diluted in vitro without precipitation. Furosemide 50 mg/mL was diluted to concentrations of 10 and 5 mg/mL with 5% dextrose in water (D5W), 0.9% saline, lactated Ringer solution (LRS), and sterile water. Acidic sterile water and basic sterile water solutions were made by the addition of hydrochloric acid and sodium hydroxide, respectively, for use as controls to assess the effect of pH extremes for each concentration. After furosemide dilution, the final pH of each sample was measured, and samples were grossly and microscopically examined for clarity and crystal formation immediately and 1, 3, 5, and 8 hours after dilution. Gross precipitation and microscopic crystals were immediately observed in the acidic controls. Solutions of 5 mg/mL in LRS and 0.9% saline became slightly cloudy immediately, but no crystals were observed microscopically for 8 hours. Solutions of 10 mg/mL in D5W, 0.9% saline, LRS, and sterile water and solutions of 5 mg/mL in D5W and sterile water and the basic control were grossly clear, and no microscopic crystals were observed for 8 hours. On the basis of the results obtained in this in vitro investigation, this veterinary formulation of furosemide 50 mg/mL can be diluted without precipitation to a concentration of 10 mg/mL with D5W, 0.9% saline, LRS, or sterile water and to 5 mg/mL with D5W or sterile water and held for 8 hours. 相似文献
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为了探索垂柳(Salix babylonica)树叶的饲料化加工技术,在研究6个生育期(展叶期、开花初期、飞絮期、青绿期、枯黄期、落叶期)柳树叶营养物质含量变化的基础上,分别将其调制成青贮饲料,测定并比较不同生育期柳树叶制备青贮饲料的营养物质含量及发酵品质指标,并对枯黄期和落叶期树叶进行添加乳酸菌菌剂青贮对比试验。结果表明,根据原料营养物质判断,展叶期柳树叶营养品质与优质豆科牧草品质近似,但是随着生育期的延迟,柳树叶营养物质含量和饲用价值显著下降。将不同生育期柳树叶直接青贮之后,无品质改善效果,青贮饲料发酵品质差,饲用价值不大。但是,添加乳酸菌菌剂后调制的柳树叶青贮饲料发酵品质得到了显著改善。综上表明,柳树叶如果直接饲喂利用,最好选择在较为幼嫩的展叶期;如果开发利用其他生育期或枯落后的柳树叶,以添加乳酸菌菌剂调制成青贮饲料为好。 相似文献
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川西北高寒沙地不同年限高山柳林下优势植物碳、氮、磷生态化学计量特征 总被引:2,自引:0,他引:2
通过采集川西北高寒沙地不同年限(6、18、24年)高山柳林下3种优势植被藏沙蒿、裂叶独活和镰荚棘豆,分别测定分析3种植被叶片、根部C、N、P化学计量特征变化特征。结果表明:不同年限高山柳林下植被C、N、P含量及其比值间存在显著差异且呈现出不同变化趋势。林下植被C含量整体下降;叶N含量呈上升趋势,根N含量随年限增长而下降;除藏沙蒿外,林下植被P含量变化不显著;C∶N变化范围为1.92~12.86;C∶P为29.18~196.88;不同年限高山柳林下植被N∶P间虽存在差异,但均表现出主要受到P限制,表明该区域植被生长主要受P限制,应注意P养分的适当补充。 相似文献
5.
高寒区山生柳硬枝扦插灰色系统理论分析研究 总被引:2,自引:1,他引:2
本研究利用灰色系统关联度分析方法,对山生柳(Salix oritrepha)硬枝5种不同扦插处理的关联度及其扦插繁殖中的8个观察指标值间的关联度大小进行了计算分析,结果表明:山生柳硬枝扦插繁殖观测指标间的关联度大小依次为:保存率主根长度茎粗株高一级分枝数地上生物量鲜质量侧根数量;硬枝扦插5种不同处理的关联度大小依次为:覆膜简易塑料大棚育苗袋育苗杯露地。主根长度、茎粗和株高3个观测指标是影响山生柳扦插繁殖成活率的主要指标因子,覆膜处理是山生柳在高寒区最适合的快繁技术。 相似文献
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沂蒙山区杞柳害虫记述 总被引:2,自引:0,他引:2
近4年来的研究,记载了为害沂蒙山区杞柳的害虫(害螨),共计115种,分属于昆虫纲和蛛形钢,6目,31科。 相似文献
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Salix discolor Mühl. (Sd) and Salix viminalis L. (Sv) were planted under short-rotation intensive culture (SRIC) on three unirrigated abandoned farmland sites with different drainage conditions, one well-drained (S1) and the other two poorly-drained (S2, S3). One dose of dried and granulated sludge equivalent to 150 (T1) kg of “available” N ha−1 was applied to some plots in the spring of the second season while others were left unfertilized (T0). The aims of the experiment were (i) to investigate plant response (growth and productivity) to plantation site conditions and sludge application; (ii) study nutrient status by foliar analysis. Over three seasons, growth in height and aboveground biomass were greater for S. viminalis than for S. discolor on all sites. S. viminalis planted on poorly-drained site 2 had the highest biomass yield (45.28 t ha−1). Both species showed best height and diameter growth on poorly-drained sites. For both species, best performances were obtained on wastewater sludge fertilized plots. Comparative foliar analysis suggested that unfertilized sandy soil (S1) and low foliar nitrogen concentration and content were limiting factors in the performance of the two species. Soil nitrate concentration increased as a result of sludge application. Heavy metal accumulation from sludge does not represent a risk to the environment. It was concluded that S. viminalis had the best productivity on clay sites, and that a moderate dose of dried and pelleted sludge (150 kg of “available” N ha−1) may be a good fertilizer during the establishment of willows in SRIC, and may reduce nitrate leaching. 相似文献
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