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61.
低温等离子种子处理研究初报 总被引:4,自引:2,他引:2
采用低温等离子种子处理技术对大豆、玉米、番茄、甘蓝种子进行不同剂量的处理,观察对这些作物生长发育及产量的影响。结果表明,在适宜剂量处理下,4种作物产量均有所提高,最高增产效果:大豆40.76%,玉米14.4%,番茄37.3%,甘蓝22.84%。处理剂量偏高或偏低时蔬菜作物表现出明显的减产趋势,而粮食作物则表现为不增产或增产不显著 相似文献
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63.
Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares. 相似文献
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares. 相似文献
64.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):1975-1990
Abstract A population of Limonium stocksii was studied for one year at the upper end of Manora Creek along the Arabian Sea coast, near Karachi, Pakistan. The community was divided into three zones. Soil pH varied from 8.1 to 8.5. Soil conductivity was highest (191 dS m?1) in September and lowest (55 dS m?1) in June. Soil water content was relatively low and varied from 1.6% in February to 9.5% in June. Limonium stocksii maintained a persistent seed bank, which peaked at 5,887 seeds m?2 in May. Very slow growth was observed; however, plants in the intermediate zone showed better growth than the other two zones. Stem and leaf tissue water content were affected by salinity fluctuations, but root tissue water remained unaffected. Sodium (Na+) and chloride (Cl?) accumulated in stems and leaves more than other ions. Leaves also accumulated a very high amount of magnesium (Mg++) compared to roots and stems. 相似文献
65.
松针叶绿素与脂溶性复合物的提取 总被引:1,自引:0,他引:1
采用置换反应将松针中含镁叶绿素转变成水溶性叶绿素铜钠,用低浓度乙醇浸提并分离脂溶性部分,得到叶绿素铜钠速淀粉,其1%水溶液pH值为8-9,600倍稀释呈翠绿色,产品获得率为松针干粉的8%-10%,同时获得脂溶性复合物,其主要成分为VE。 相似文献
66.
《中国林业科技(英文版)》2009,(1)
According to AWPA E11-2006 standard,copper fixation rates of several copper-based formulations,such as ammoniacal copper,amine copper,and ammoniacal-ethanolamine copper,as well as alkaline copper quaternary(ACQ),were tested and compared in this paper.And the fixation rates of tebuconazole(TEB) and propiconazole(PPZ) in several formulations,such as copper azole,emulsified type and solvent type,were also compared.The determination of copper content in the leachate was analyzed by atomic absorption spectrom... 相似文献
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68.
饮水高钠诱发的肉鸡腹水综合征的血液流变学特征 总被引:7,自引:2,他引:5
为查明高钠饮水与肉鸡腹水综合征的病因学关系,将240只健康AA肉鸡随机均分为试验Ⅰ、Ⅱ和对照3个组,从8日龄起分别饮用含Na+为0.06%、0.12%和0.00%的饮水,动态对比观察各组肉鸡临床表现、血液红细胞压积(PCV)、红细胞变形性(ED)、右心室(RV)和全心室(TV)的重量比(RV/TV)。结果表明,高钠饮水可以诱发腹水综合征;肉鸡在摄入过量Na+时,出现肺动脉高压(PH)、PCV增加和ED下降等血液流变学特性的改变,促进了腹水综合征的形成。 相似文献
69.
日粮缺锌对猪血液生理生化指标及组织锌,铜含量的影响 总被引:2,自引:0,他引:2
用Ca∶Zn为60∶1、330∶1和516∶1的3种日粮分别饲喂3组仔猪120d,对试验猪的临床症状和部分血液生理生化指标的变化进行了动态观察,并测定了试验猪12种组织的锌、铜含量。结果表明,血液白细胞数和血清碱性磷酸酶,试验B组(Ca∶Zn为516∶1)与对照组(Ca∶Zn为60∶1)之间有显著差异(P<0.05);试验A、B组猪(Ca∶Zn为330∶1和516∶1)被毛锌含量、肝锌含量和肝铜锌比极显著低于对照组(P<0.01)。这些指标对于仔猪缺锌的早期诊断具有重要的诊断价值。 相似文献
70.
将360只1日龄天府肉鸭随机分为6组,分别以对照日粮(Cu8mg/kg)和高铜日粮(Ⅰ组:Cu100mg/kg;Ⅱ组:Cu200mg/kg;Ⅲ组:Cu400mg/kg;Ⅳ组:Cu600mg/kg;Ⅴ组:Cu800mg/kg)饲喂6周,研究日粮铜水平对雏鸭肝氧化状态及肝细胞凋亡的影响。结果显示,与对照组比较,Ⅳ组和Ⅴ组肝铜锌SOD和谷胱甘肽过氧化物酶活性降低(P〈50.01),Ⅲ组、Ⅳ组和Ⅴ组羟自由基和丙二醛含量显著升高(P〈0.01),Ⅰ组和Ⅱ组肝铜锌SOD和谷胱甘肽过氧化物酶活性升高(P〈0.01)。高铜组肝细胞凋亡率随日粮铜水平的升高而增加。表明,日粮铜水平为400mg/kg以上时可引起肝抗氧化功能降低和肝细胞凋亡率升高。 相似文献