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81.
82.
恩诺沙星及其代谢产物在奶山羊的药动学及乳中药物浓度 总被引:2,自引:0,他引:2
本试验研究单剂量静脉注射、肌肉注射和乳房灌注恩诺沙星(2.5mg/kg)在健康奶山羊的药动学及乳中药物浓度。采用HPLC法测定血浆和乳中恩诺沙星及其代谢产物环丙沙星的浓度,用统计矩原理处理血浆中药物浓度-时间数据,计算非房室模型的药动学参数。静脉注射、肌肉注射和乳房灌注恩诺沙星的t1/2β分别为1.32、1.55、0.99h;AUC为1.06、3.04、2.66mghL^-1;恩诺沙星的代谢分数为35.01%、44.06%、45.73%;环丙沙星的t1/2β为1.81、2.94、2.32h。乳中的药物浓度高于同期血中药物浓度,且乳中环丙沙星浓度高于恩诺沙星浓度并维持更长的时间。 相似文献
83.
The function, composition and analysis of cerebrospinal fluid in companion animals: part II - analysis 总被引:1,自引:0,他引:1
Accurate analysis of cerebrospinal fluid (CSF) provides a wide range of information about the neurological health of the patient. CSF can be withdrawn from either of two cisterns in dogs and cats using relatively safe techniques. Once CSF has been collected it must be analysed immediately and methodically. Evaluation should consist of macroscopic, quantitative and microscopic analyses. As part of a quantitative analysis, cell counts and infectious disease testing are the most important and potentially sensitive indicators of disease. Although certain pathologies can be described, microscopic analysis will rarely be specific for any disease, emphasising the adjunctive nature of this diagnostic modality. 相似文献
84.
85.
Paolo Zucca Giovanni Di Guardo Roberto Pozzi-Mucelli Dino Scaravelli Marco Francese 《Journal of zoo and wildlife medicine》2004,35(3):391-394
A mature male Risso's dolphin (Grampus griseus) stranded along the coasts of Friuli Venezia Giulia, northeast Italy, in May 2001. Parasitic infection with Crassicauda grampicola is often found in the tympanic bullae and pterygoid sinuses in many of the Risso's dolphins examined from the same area. For this reason, it was decided to perform computed tomography of the head to assess this imaging technique for the diagnosis of crassicaudosis in dolphins. A full postmortem examination confirmed the pathologic findings of the computed tomography scan. This technique can be considered a useful adjunct in the diagnosis of cranial crassicaudosis in live dolphins. 相似文献
86.
马铃薯SGT3基因表达及其启动子功能分析 总被引:2,自引:0,他引:2
鼠李糖转移酶(rhamnosyltransferase SGT3)是植物糖苷生物碱合成的关键酶,它主要调控α-茄碱和α-查茄碱从其β形式的转化。本文研究马铃薯栽培种SGT3基因的表达特点及其启动子的功能。实时定量PCR结果发现在红光照射24 h后,SGT3的表达量是黑暗处理的26.8倍,说明红光显著诱导了SGT3的表达;为进一步分析该基因的光调控机理,本项研究克隆到SGT3上游长度为2449 bp的启动子序列,通过分析发现该启动子的转录起始位点位于翻译起始位点上游-152 bp,同时确定了该启动子核心序列及上游增强子、抑制子序列,受病原菌、损伤、干旱、ABA 激素及一系列光调控的顺式元件。构建不同长度(349,572,979,1312和1870 bp)的该启动子驱动报告基因GUS的植物表达载体并转化烟草。结果证明,不同长度的SGT3启动子都可以启动GUS表达,但没有CMV 35S启动的GUS表达量高;其中在P572和P979的表达强度较高,这可能与该片段含有启动子的正调控元件(GATA BOX,5′UTRPY-RICH STRETCH)有关,GUS表达强度在P1312和P1870中明显减弱,预测到该区段存在抑制基因表达的负调控元件(WRKY710S);SGT3启动子的组织特异性实验表明GUS染色主要集中在烟草叶片的叶脉部分,茎中的表皮、韧皮部及木质部,但髓部几乎不表达,根中主要分布在根冠、分生区以及维管束组织中。上述结果为将来研究SGT3在糖苷生物碱合成过程中的调节功能提供了依据。 相似文献
87.
Berardinelli P Russo V Martelli A Nardinocchi D Di Giacinto O Barboni B Mattioli M 《Anatomia, histologia, embryologia》2004,33(1):23-27
Apoptosis is the cellular mechanism of ovarian follicular atresia. The major downstream effector of this phenomenon in many tissues is caspase-3 but little is known about its role in pig ovarian apoptosis. In the present study, we detected the localization of caspase-3 in parallel with nuclear fragmentation (TUNEL) on healthy and early atretic antral follicles. In healthy antral follicles caspase-3 and TUNEL positivity were occasionally recorded within theca layer. The incidence of DNA fragmentation, as indicated also by the biochemical detection, increased mainly in the granulosa layer of early atretic follicles. Quantitative analysis revealed, besides, that atresia was accompanied by a higher incidence of caspase-3 (57.20 +/- 20.05 versus 3.64 +/- 0.61 positive cells in atretic versus healthy follicles, respectively; P < 0.05), of TUNEL positivity (20.13 +/- 9.33 versus 0.42 +/- 0.12; P < 0.05) and simultaneous immunostaining for caspase-3 and TUNEL (15.02 +/- 6.95 versus 0.31 +/- 0.05; P < 0.05) in the granulosa layer. In detached granulosa cells isolated from the follicular fluid of early atretic follicles a further significantly increase was recorded in the percentage of TUNEL positivity and in the incidence of cells that showed colocalization of caspase-3 activity and DNA fragmentation. Granulosa cells of early atretic follicles exhibited a higher positivity for caspase-3 localized in the cytoplasm and occasionally in the nucleus area of granulosa cells. These results indicate that capsase-3 was involved and precociously activated during the process of atresia. Finally, the progressively higher incidence of TUNEL positivity and of double immunostaining in atretic cells collected within the follicular fluid seems to indicate that proteases activity leads only tardily in a detectable DNA fragmentation. 相似文献
88.
Jacopo Guccione Diego Piantedosi Antonio Di Loria Vincenzo Veneziano Paolo Ciaramella 《Journal of Equine Veterinary Science》2014
The heart rates (HR) and rhythms of 15 healthy donkeys of various ages, both sexes, and various breeds were analyzed throughout 24-hour Holter monitoring. The animals were evaluated at rest in their daily environment without the presence of investigators causing stress, using a three-channel digital Holter recorder. Analysis revealed a maximal HR range from 62.5 to 93.7 beats/min (mean, 72.50 ± 7.51 beats/min), whereas the minimal HR ranged from 29.7 to 42.2 beats/min (mean, 34.90 ± 4.22 beats/min). The daily mean HR was 47.55 ± 3.70 beats/min. The daytime mean HR was 49.39 ± 2.77 beats/min, whereas the night time rate was 46.22 ± 4.38 beats/min. Sinus bradycardia and sinus tachycardia were detected in 7 and 10 of 15 studied donkeys, respectively. Cardiac dysrhythmias due to high vagal tone such as sinoatrial heart block and second-degree atrioventricular heart block were occasionally recorded in 1 and 3 donkeys, respectively. A higher mean HR and fewer cardiac dysrhythmias were observed in donkeys than in horses and ponies at rest. These findings could be justified by differences in the autonomic nervous system tone. 相似文献
89.
采用解析法对蔬菜钵苗移栽机取苗臂凸轮机构进行了详细设计,以解决目前机构推苗作业时间长、速度慢而影响推苗成功率的问题。根据移栽机取苗和推苗作业时取苗针的运动要求,以及取苗臂的结构尺寸,建立凸轮机构设计的数学模型,优化凸轮推程运动角,进而得到凸轮实际轮廓曲线,进行了机构的运动及压力角分析。建立取苗机构的三维实体模型,制造出其物理样机,采用ADAMS软件进行虚拟样机运动仿真,开展高速摄像运动试验。仿真结果和试验结果基本一致,表明改进设计是正确和合理的,同时比较改进设计结果和原设计结果可知,所设计的凸轮机构能够满足蔬菜钵苗移栽的要求,且试验推苗时间比原设计有效缩短了27.9%,有助于提高推苗成功率和蔬菜钵苗移栽机的工作性能。 相似文献
90.
甘蔗黄叶病和甘蔗花叶病是我国甘蔗最主要的病毒病,感病品种产量下降和品质变劣,传统方法难以防治。RNA干扰技术使培育抗病毒甘蔗品种成为可能。本研究根据甘蔗黄叶病毒和侵染甘蔗的高粱花叶病毒结构与功能特性,广泛收集不同来源病毒分离物CP基因序列,经过比对选取保守序列作为干扰序列。通过在序列两端添加酶切位点,合成并连接成双价甘蔗黄叶病和花叶病毒干扰序列,然后构建到中间载体p HANNIBAL上,形成双价RNAi干扰结构,最后插入到p ART27上形成干扰表达载体。利用基因枪轰击甘蔗品种福农15号愈伤组织进行转化,经G418筛选获得抗性再生植株。通过提取DNA和RNA分析,证实双价RNAi干扰结构不仅以不同拷贝整合到甘蔗基因组中,而且得到了转录表达。 相似文献