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101.
OBJECTIVE: To determine radiocarpal (RC) joint synovial fluid and plasma ceftiofur concentrations after regional intravenous perfusion (RIP) and systemic intravenous (IV) administration. STUDY DESIGN: Experimental cross-over study. ANIMALS: Five normal adult horses. METHODS: One RC joint was randomly selected for RIP and the contralateral RC joint was sampled to determine intrasynovial ceftiofur concentrations after IV administration. Wash-out between IV and RIP was > or = 14 days. After surgical introduction of an intraarticular catheter, ceftiofur (2 g) was administered under general anesthesia either IV or by RIP after tourniquet application. Plasma and synovial fluid were collected over 24 hours. Samples were analyzed using high-performance liquid chromatography with ultraviolet detection and the results were statistically analyzed using a linear mixed effect model. RESULTS: Mean synovial fluid ceftiofur concentrations were consistently higher after RIP than after IV administration and were > 1 mug/mL (minimal inhibitory concentration [MIC] for common pathogens) for >24 hours. Mean synovial fluid peak concentration of ceftiofur after RIP and IV administration was 392.7+/-103.29 microg/mL at 0.5 hours postinjection (HPI) and 2.72+/-0.31 mug/mL at 1 HPI, respectively. Large variations in synovial fluid and plasma ceftiofur concentrations were observed between horses regardless of administration technique. RIP did not cause adverse effects. CONCLUSIONS: Under the present experimental conditions RIP with ceftiofur (2 g) induced significantly higher intraarticular antibiotic concentrations in the RC joint in comparison with IV administration. Moreover, after RIP, synovial fluid ceftiofur concentrations remain above the MIC for common pathogens (1 microg/mL) for > 24 hours. No adverse effects from the technique or the antibiotic were observed. CLINICAL RELEVANCE: RIP with high doses of ceftiofur may be a beneficial adjunctive therapy when treating equine synovial infections which are caused by cephalosporin susceptible microorganisms.  相似文献   
102.
天然香精是从芳香植物中用物理方法提取的有机混合物,具有独特、自然、舒适的香气和香韵,在香料工业、日化、食品等领域有广泛应用,但利用传统方法萃取易使其原有香味失真;超临界CO2流体萃取是一种新型分离技术,特别适于不稳定及热敏性天然产物的萃取,利用该技术萃取天然香精可得到高品质高价值的产品。概述了超临界CO2流体萃取技术,介绍了近几年该技术萃取植物天然香精及其与其他分离技术结合的相关研究,探讨了该技术在应用中存在的问题及其发展前景,旨在为该技术萃取天然香精的进一步应用提供参考。  相似文献   
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105.
HPAM/Cr3+弱凝胶调驱体系的室内研究   总被引:1,自引:0,他引:1  
在室内研制了一种可供较高温度、高矿化度油藏深部调剖用的HPAM/Cr3 弱凝胶调驱体系.考察了聚合物浓度、交联剂浓度、稳定剂浓度、温度、矿化度以及pH值对成胶性能的影响.确定了HPAM/Cr3 弱凝胶体系的最佳形成条件:HPAM聚合物1200mg/L;铬交联剂J(以Cr3 计)浓度40mg/L;稳定剂W浓度40mg/L;体系pH值6~8;最佳使用温度70℃.HPAM/Cr3 弱凝胶体系可实现成胶时间可控,凝胶强度可调.  相似文献   
106.
Alveolar macrophages (AMs) constitute the first line of defence in the lung of all species, playing a crucial role in the regulation of immune responses to inhaled pathogens. A detailed understanding of the function and phenotype of AMs is a necessary pre-requisite to both elucidating their role in preventing opportunistic bacterial colonisation of the lower respiratory tract and developing appropriate preventative strategies. The purpose of the study was to characterise this important innate immune cell at the tissue level by making functional and phenotypic comparisons with peritoneal macrophages (PMs). We hypothesised that the tissue of origin determines a unique phenotype of AMs, which may constitute an appropriate therapeutic target for certain equine respiratory diseases. Macrophages isolated from the lung and the peritoneal cavity of 9 horses were stimulated with various toll like receptor (TLR) ligands and the production of nitrite, tumour necrosis factor alpha (TNFα), interleukin (IL) 10 and indoleamine 2,3-dioxygenase (IDO) were measured by the Griess reaction and enzyme linked immunosorbent assay (ELISA) and/or quantitative polymerase chain reaction, respectively. Cells were also compared on the basis of phagocytic-capacity and the expression of several cell surface markers. AMs, but not PMs, demonstrated increased TNFα release following stimulation with LPS, polyinosinic polycytidylic acid (Poly IC) and heat-killed Salmonella typhinurium and increased TNFα and IDO mRNA expression when stimulated with LPS. AMs showed high expression of the specific macrophage markers cluster of differentiation (CD) 14, CD163 and TLR4, whereas PMs showed high expression of TLR4 only. AMs, but not PMs, demonstrated efficient phagocytic activity. Our results demonstrate that AMs are more active than PMs when stimulated with various pro-inflammatory ligands, thus supporting the importance of the local microenvironment in the activation status of the macrophage. This information provides a valuable knowledge base on which to improve our understanding of the role of macrophages and their microenvironment in equine innate immunity.  相似文献   
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108.
利用化学合成的方法获得蜜蜂肽Apidaecin 1B(AP 1B)及其系列突变体,通过对不同细菌的MIC测定,筛选获得了抑菌活性更高的改良肽AP2.AP2的特性研究结果表明,在低pH值条件下对胃蛋白酶稳定性好,并且对热、模拟肠液有一定的耐受性.研究结果将为蜜蜂肽Apidaecin的开发及其在畜牧业中的应用奠定基础.  相似文献   
109.
Atypical myopathy is highly fatal, but about a quarter of affected horses survive. This highlights the need for provision of supportive treatment for these cases. This review is a practical guideline for equine practitioners and includes suggestions for close monitoring of involved organ systems and discusses options of supportive treatment based on current knowledge of the condition.  相似文献   
110.
将佛奥和鄂植两个品种油橄榄扦插条放入生根液浓度分别为0mg·L^-1、100pmm、200mg·L^-1、300mg·L^-1、400mg·L^-1的生根液激素中浸泡,进行油橄榄扦插条生根率的研究。结果表明,没有生根液浸泡的插穗虽有少量的产生愈伤组织,但几乎不会生根;佛奥在0mg·L^-1、100mg·L^-1、200mg·L^-1、300mg·L^-1、400mg·L^-1浓度生根液浸泡下的生根率分别为3%、37%、42%、76%、63%;鄂植在0mg·L^-1、100mg·L^-1、200mg·L^-1、300mg·L^-1、400mg·L^-1浓度生根液浸泡下的生根率分别为2%、21.25%、40.5%、70.25%、53.13%;由此可以得出,油橄榄扦插浸泡生根液激素的最适浓度为300mg·L^-1。  相似文献   
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