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131.
【目的】深入了解2株广西鹅源基因XII型新城疫病毒(NDV)的病原学特征,为NDV流行分布的系统监测和新城疫(ND)的科学防控提供参考依据。【方法】对2株广西鹅源基因XII型NDV(Goose/China/GX02/2018和Goose/China/GX17/2018)进行病毒噬斑纯化,通过致死鸡胚平均死亡时间(MDT)和脑内接种致病指数(ICPI)试验确定其致病性,分析F蛋白和HN蛋白氨基酸序列与参考毒株的差异位点,并基于F基因全长进行遗传进化分析。【结果】经过DF-1细胞4个代次噬斑纯化可获得2株分离株的纯化株,对应的MDT分别为54和48 h,ICPI均为1.65。2株分离株的基因组长度均为15192 nt,其3'端引导序列为55 nt,5'端尾随序列为114 nt;基于F基因核苷酸序列相似性构建的基因XII型NDV系统发育进化树显示,2株分离株(Goose/China/GX02/2018和Goose/China/GX17/2018)均属于基因XIIb亚型,与我国广东分离株属于同一基因亚型,且我国2010年的分离株、2011年的分离株及2017年后的分离株分别形成3个小分支。2株分离株的F蛋白裂解位点均为112RRQKRF117,与南美分离株(XIIa亚型)和越南分离株(XIId亚型)相比,在信号肽区域、融合肽区域、七肽重复区和跨膜区共有14个氨基酸差异位点,其中2个氨基酸差异位点(19I→V和294N→S)是广西分离株所特有。2株分离株的HN蛋白跨膜区及抗原中和区氨基酸序列与我国广东分离株均一致,与南美分离株(XIIa亚型)相比存在7个氨基酸差异位点(27V→I、28A→S、34V→I、41A→T、42V→A、263K→R和347E→D)。【结论】我国分离株(XIIb亚型)与南美分离株(XIIa亚型)和越南分离株(XIId亚型)在F蛋白和HN蛋白的氨基酸差异可能与其对鸡群的致病力差异有关。此外,基因XII型NDV一直处于不断进化中,而需持续监测该基因型NDV的流行分布情况。 相似文献
132.
目的 探究广州动物园一例死亡白狐Alopex lagopus肾脏中鉴定出的星状病毒的遗传变异情况。方法 对死亡白狐进行剖检,利用半巢式RT-PCR对内脏器官进行病原学检测,对扩增出的病毒株的RdRp基因序列进行相似性分析。结果 死亡白狐的肾脏苍白肿大,被膜难以剥离,肾脏中检测出的星状病毒RdRp基因呈阳性。RdRp基因与9株参考毒株的核苷酸相似性为67.5%~96.2%,其中与香港猫源星状病毒1637F的核苷酸相似性(96.2%)最高。结论 本研究为星状病毒在野生哺乳动物间的跨种传播及肠外器官中的感染提供了依据。 相似文献
133.
【目的】研究蓝刺头花絮水提物的降血糖作用。【方法】采用煎煮法制备蓝刺头花絮水提物。使用四氧嘧啶诱导糖尿病小鼠模型,并随机分为4组,每组10只,蓝刺头高、中、低剂量组小鼠每天分别灌胃1.00,0.50和0.25g/mL的蓝刺头花絮水提物,对照组灌等量蒸馏水,于试验0,7,14和21d测定糖尿病小鼠空腹血糖、体质量;21d测定小鼠口服糖耐量、肝糖原、血清胰岛素、胰高血糖素及肾上腺素的含量。【结果】蓝刺头花絮水提物能够显著降低糖尿病小鼠的空腹血糖,改善糖尿病小鼠的口服糖耐量,升高肝糖原及血清胰岛素水平,极显著降低血清肾上腺素含量,对体质量和血清胰高血糖素含量无显著影响。【结论】蓝刺头花絮水提物能够降低糖尿病小鼠的血糖水平,且呈剂量依赖关系。 相似文献
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136.
Rush BR Biller DS Davis EG Higginbotham ML Klocke E Miesner MD Rankin DC 《Journal of veterinary medical education》2011,38(3):242-250
Kansas State University implemented a Web-based program to assess students' competency to perform technical skills during clinical rotations throughout the fourth year of the veterinary curriculum. The classes of 2009 and 2010 recorded a minimum number of procedures (104 and 103, respectively) from a menu of more than 220 recommended procedures. Procedures were categorized by species (small animal, equine, food animal) and disciplines (imaging, anesthesia, diagnostic medicine/necropsy). Ophthalmology was added as a fourth discipline for the class of 2010. Students recorded procedures into the Web-based system, including information about the patient, procedure performed, supervisor, and a self-assessment of performance. Faculty, staff, and house officers evaluated the procedures electronically by confirming that they witnessed the procedure and providing qualitative and written feedback. The class of 2009 recorded 18,492 procedures (M=171/student) and the class of 2010 recorded 16,935 procedures (M=158/student). Two students from each class (2009 and 2010) did not complete the minimum required skills during clinical rotations and returned to perform procedures immediately before (n=3) or immediately after (n=1) graduation to receive their diploma. The Web-based system captured a large number of assessments of technical competency performed in the clinical setting. The system provided students with formative feedback throughout the clinical year, ensured equitable distribution of procedural opportunities across the student body, and required minimal additional resources. 相似文献
137.
Campagnolo ER Rankin JT Daverio SA Hunt EA Lute JR Tewari D Acland HM Ostrowski SR Moll ME Urdaneta VV Ostroff SM 《Zoonoses and public health》2011,58(7):500-507
We report the earliest recognized fatality associated with laboratory-confirmed pandemic H1N1 (pH1N1) influenza in a domestic cat in the United States. The 12-year old, indoor cat died on 6 November 2009 after exposure to multiple family members who had been ill with influenza-like illness during the peak period of the fall wave of pH1N1 in Pennsylvania during late October 2009. The clinical presentation, history, radiographic, laboratory and necropsy findings are presented to assist veterinary care providers in understanding the features of this disease in cats and the potential for transmission of infection to pets from infected humans. 相似文献
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139.
Hydromorphone (H) may be an effective analgesic agent in cats, but fear of negative behavioral side‐effects associated with opioids is cited as a reason for avoiding this class of analgesics in cats. This study was designed to assess onset and duration of antinociception using an established feline thermal threshold model in cats, given an accepted clinical dose of 0.1 mg kg?1 of H. In addition, cats were observed for changes in behavior and other side‐effects. Six adult cats from an established colony (four spayed females and two castrated males, 4.7–7.0 kg) received 0.1 mg kg?1 H IV following establishment of baseline thermal threshold (TT) values. TT was tested at 15 minutes post‐injection, then at every 30–60 minutes for 12 hours. Side‐effects and behavior changes were recorded for 12 hours. Changes in TT over time were analyzed using a one‐way anova ; a p‐value <0.05 was considered significant. TT increased from a pre‐treatment value of (mean ± SD) 40.9 ± 1.65 °C to instrument cutout (55.5 °C) within 30 minutes for 5/6 cats. Mean TT was significantly elevated above baseline from 15 to 450 minutes after treatment. There was a significant increase in skin temperature from 15 to 300 minutes with peak increase of 1.55 °C at 135 minutes. Side‐effects included mydriasis (6/6) and nausea (4/6), characterized by licking, foaming, and gagging. Mydriasis occurred within 10–30 seconds of injection and persisted for 5–7 hours. Nausea was noted within 2 minutes of injection and persisted for 30–90 minutes; no vomiting occurred. Commonly observed behavioral changes included ventral tail curl (6/6 cats, onset 5–45 minutes, duration 4–5 hours) and euphoria (5/6 cats, onset <6 minutes for 4/6, duration 1–6 hours). 2/6 cats were profoundly sedate. Three cats showed signs of dysphoria with or without increased motor activity with variable onset and duration. Dysphoric behavior included staring, pacing, vocalizing, and sudden movements. 3/6 cats exhibited both euphoria and dysphoria at different times during the study. At no time were cats difficult to restrain or work with. Return to baseline behavior occurred 7–8.5 hours post‐injection. Mydriasis did not correlate closely with antinociception. Signs of sedation and euphoria corresponded with onset of antinociception, but not duration. Tail curl signs correlated with antinociception. In this model, H proved to be a rapid acting, potent, analgesic with a long (7.5 hours) duration of action. The most common behavioral changes noted were ventral tail curl, euphoria, and sedation. Mydriasis and nausea were noted as side‐effects. 相似文献
140.