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51.
无菌分离、冲洗7日龄内番鸭长骨骨髓,收集、培养破骨细胞(Osteoclasts,OC)。培养过程中对照组不添加钙、磷因子,试验组加入不同浓度比例的钙磷双因子(Ca∶P分别为2∶1、1∶1、1∶2),进行破骨细胞骨髓诱导培养。倒置显微镜观察细胞形态,于培养1、3d进行抗酒石酸酸性磷酸酶染色(TRAP)计数,培养7d后扫描电镜观察象牙片吸收陷窝。结果显示,培养3d时试验组TRAP阳性细胞均多于对照组,差异极显著(P〈0.01);试验2∶1组与1∶1组差异不显著(P〉0.05),其余各组间均差异极显著(P〈0.01);扫描电镜观察,象牙片吸收陷窝程度与钙磷比例大小(2∶1、1∶1、1∶2)成反比。当钙磷比例为1∶2时,破骨细胞数量最多,功能活跃。结果表明,鸭破骨细胞骨髓诱导培养体系已成功建立。 相似文献
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安丽娜 《四川畜牧兽医学院学报》2008,(3):129-132
20世纪80年代出现的寻根文学是新时期文学发展的一次重要探索。它对于新时期文学的意义是巨大而深远的。它提供了政治话语写作以外的另一种写作范式,指明了小说可以朝着无限广阔的文化领域进军,召唤着作家大胆借鉴新的创作资源。当它为后人提供可资借鉴的学术资源时,也存在着许多不足。文中主要从“寻根文学”的渊源、背景、理论、作家作品及所受到的外来影响等多方面试图对寻根文学做一次较为全面的梳理和把握。 相似文献
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广义披碱草属包括了披碱草属、鹅观草属、猬草属、裂颖草属和仲彬草属。为深入研究这5个小麦族多年生属的系统地位、母本来源及St染色体组的来源和分化等问题,本研究根据叶绿体DNA trnL-F序列构建了系统树和网状结构图。结果表明,1)广义披碱草属物种的母本不完全来源于拟鹅观草属的St染色体组,其中黑药仲彬草和梭罗仲彬草的母本染色体组为P染色体组,Hystrix duthiei及长芒猬草的母本染色体组为Ns染色体组;2)系统树中反映了P、W和St染色体组之间具有较近的亲缘关系,它们与H和Ns染色体组的关系较远;3)仲彬草属中黑药仲彬草和梭罗仲彬草与冰草属的二倍体物种聚类在一起,表明黑药仲彬草和梭罗仲彬草与冰草属的关系较近;猬草属中猬草聚在St支中,而H. duthiei和长芒猬草包括在Ns支中,表明它们具有不同的染色体组组成;4)5个不同地理分布的具有St染色体组的拟鹅观草属二倍体物种没有形成一个单系组,表明St染色体组在二倍体物种中存在一定程度的分化;在异源多倍体物种中,其St染色体组的质体序列构成了不同的分支,表明St染色体组在多倍体物种中也具有分化;5)亚洲分布的拟鹅观草属二倍体物种可能参与了大部分欧亚物种的起源,北美分布物种的St染色体组可能来源于北美的拟鹅观草属物种;有些物种在多倍化起源过程中可能发生了重复杂交过程。 相似文献
55.
LI Hui-feng LI Qing-hong LI Hong-quan HAO Rui-rong CHEN Jian-hui GU Jian-wen 《中国畜牧兽医》2015,42(9):2459-2466
The objective of this study was to compare the effect of three Chinese herbal medicine (medicated leaven, hawthorn, fructus hordei germinates) on histomorphology of different parts of small intestine in weaning piglets.40 28-day old ternary pigs (Duroc×Landrace×Yorkshire) with the body weight (8.13±1.32)kg were divided into four groups, control group, medicated leaven group, hawthorn group and fructus hordei germinates group, and feeding with 1% Chinese herbal medicine, there were two repeats in each group and each repeat had 5 piglets, slaughtering and sampling at 7th and 14th day morning, respectively, sections were used for HE staining.The staining tissues were taken pictures under a microscope camera (200×) and measured VH, CD, IWT and V/C in different parts of small intestine with Image-Pro Plus.The result showed that the IWH of ileum in medicated leaven group was significantly or extremely significantly higher than control group (P<0.05;P<0.01).The VH and IWT of duodenum and jejunum at 7th day in hawthorn group were extremely significantly lower than control group (P<0.01);The IWT of ileum and the VH of ileum at 14th day were extremely significantly higher than control group (P<0.01).In fructus hordei germinates group, the VH of duodenum and jejunum at 7th day and IWT of jejunum were extremely significantly lower than control group (P<0.01);The CD of ileum at 7th day, the IWT of duodenum and ileum at 7th day were extremely significantly higher than control group (P<0.01).The effects of different simple Chinese herbal medicine on histomorphology of different parts of small intestine in piglets were different, because of the different digestive functions of small intestine, the most effects of Chinese herbal medicine an duodenum, jejunum and ileum were fructus hordei germinates, medicated leaven and hawthorn, respectively. 相似文献
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J. HEWSON R. JOHNSON L. G. ARROYO A. DIAZ‐MENDEZ J. A. RUIZ‐LÓPEZ Y. GU J. R. E. Del CASTILLO 《Journal of veterinary pharmacology and therapeutics》2013,36(1):68-77
Hewson, J., Johnson, R., Arroyo, L. G., Diaz‐Mendez, A., Ruiz‐López, J. A., Gu, Y., del Castillo, J. R. E. Comparison of continuous infusion with intermittent bolus administration of cefotaxime on blood and cavity fluid drug concentrations in neonatal foals. J. vet. Pharmacol. Therap. 36 , 68–77. Healthy neonatal foals were treated with cefotaxime by bolus (40 mg/kg IV q6h for 12 doses; n = 10) or by infusion (loading dose of 40 mg/kg IV followed by continuous infusion of a total daily dose of 160 mg/kg per 24 h for 3 days; n = 5). Population pharmacokinetics was determined, and concentrations in cavity fluids were measured at steady state (72 h). Highest measured serum drug concentration in the bolus group was 88.09 μg/mL and minimum drug concentration (Cmin) was 0.78 μg/mL at 6‐h postadministration (immediately before each next dose), whereas infusion resulted in a steady‐state concentration of 16.10 μg/mL in the infusion group. Mean cefotaxime concentration in joint fluid at 72 h was higher (P = 0.051) in the infusion group (5.02 μg/mL) compared to the bolus group (0.78 μg/mL). Drug concentration in CSF at 72 h was not different between groups (P = 0.243) and was substantially lower than serum concentrations in either group. Insufficient data on pulmonary epithelial lining fluid were available to compare the methods of administration for cefotaxime in this cavity fluid. Results support continuous drug infusion over bolus dosing in the treatment for neonatal foal septicemia to optimize time that cefotaxime concentration exceeds the minimum inhibitory concentration of common equine pathogens. 相似文献
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