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将含有裂解酶基因重组温控裂解质粒pBBR1MCS：：PR-PL-E电转化至粗糙型布鲁菌M111中，构建重组布鲁菌M111（pBBRlMCS：：PR-PL-E）。重组菌株在28℃培养，42℃诱导表达裂解酶E，从而制备布鲁菌菌壳。绘制布鲁菌生长曲线及裂解曲线，计算裂解率并用透射电镜观察布鲁菌菌壳的形态。结果显示，成功制备了布鲁菌菌壳，温控裂解质粒pBBRIMCS：：PR-PL-E对布鲁菌的裂解率为100％。透射电镜观察可见细菌内容物部分流出，细菌表面出现不同程度的皱缩，细胞形态发生变化。结果表明，本试验成功制备了粗糙型布鲁菌菌壳，初步研究了其基本特性，为下-步开展布鲁菌菌壳疫苗的研究奠定了基础。 相似文献
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将含有裂解酶基因重组温控裂解质粒pBBR1MCS∷PR-PL-E电转化至粗糙型布鲁菌M111中,构建重组布鲁菌M111(pBBR1MCS∷PR-PL-E)。重组菌株在28℃培养,42℃诱导表达裂解酶E,从而制备布鲁菌菌壳。绘制布鲁菌生长曲线及裂解曲线,计算裂解率并用透射电镜观察布鲁菌菌壳的形态。结果显示,成功制备了布鲁菌菌壳,温控裂解质粒pBBR1MCS∷PR-PL-E对布鲁菌的裂解率为100%。透射电镜观察可见细菌内容物部分流出,细菌表面出现不同程度的皱缩,细胞形态发生变化。结果表明,本试验成功制备了粗糙型布鲁菌菌壳,初步研究了其基本特性,为下一步开展布鲁菌菌壳疫苗的研究奠定了基础。 相似文献
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新城疫病毒样颗粒已开发成一种高效递送外源蛋白的载体平台。本研究在小鼠模型中开展了嵌合布鲁菌BCSP31病毒样颗粒(BCSP31-cVLPs)免疫原性及其保护效力评价。体内试验数据表明,BCSP31-cVLPs能有效激活脾脏中树突状细胞,进而促进初始型CD3^+CD4^+ T的活化。ELISA法检测小鼠血清结果表明,BCSP31-cVLPs可刺激机体产生针对重组BCSP31蛋白的特异性抗体水平,且呈剂量依赖性。流式细胞术检测结果显示,BCSP31-cVLPs可激活T细胞并使其分化。攻毒结果表明,BCSP31-cVLPs具有与疫苗株M5相当的免疫保护效力。本研究为新型布鲁菌疫苗的研制提供了数据支撑,并扩展了新城疫病毒样颗粒疫苗载体平台的应用。 相似文献
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为开发一种安全有效的布鲁氏菌疫苗,解决现有A19、S2和M5等弱毒疫苗存在较强毒力可感染人,且无法通过血清学方法将其免疫抗体与野毒感染抗体进行鉴别区分的问题,本试验将含有噬菌体PhiX174裂解酶基因E的质粒转化至A19疫苗株,构建菌影疫苗(A19-BG)菌株,并检验其遗传稳定性及对小鼠的安全性、免疫效果和保护效果。结果显示,构建成功的A19-BG菌株传代20代仍稳定,热诱导48 h后可完全灭活,菌体穿孔明显。A19-BG疫苗免疫小鼠7 d后免疫部位无不良反应,14 d后脾脏无可见病理变化,与空白对照组相比脾脏重量无显著差异(P>0.05)。一免和二免后14 d,免疫小鼠的布鲁氏菌抗体、白细胞介素4(IL-4)和γ干扰素(IFN-γ)水平持续升高,产生了良好的体液和细胞免疫反应。布鲁氏菌2308强毒株攻毒免疫小鼠,免疫保护率可达87.5%,保护效果良好。结果表明,构建的A19-BG疫苗具有良好的稳定性、安全性、免疫效果和保护效果,有望成为一种极具潜力的布鲁氏菌新型疫苗。 相似文献
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旨在分析布鲁菌（Brucella）转录调节因子HFQ诱导机体产生的免疫反应。以热灭活牛种布鲁菌S2308为模板,根据GenBank登录的S2308 hfq基因序列（BAB1_1134）设计引物,PCR扩增hfq基因片段后,将其克隆至原核表达载体pET-32a,转化大肠杆菌BL21（DE3）感受态细胞,诱导HFQ蛋白表达;利用SDS-PAGE电泳以及Western blot对重组HFQ蛋白（rHFQ）进行分析;pET-32a空载体、rHFQ和疫苗株M5-90刺激小鼠巨噬细胞RAW 264.7,利用ELISA试剂盒检测细胞因子IFN-γ和IL-4的表达水平;将pET-32a、rHFQ和M5-90免疫小鼠后,检测小鼠脾细胞中IFN-γ和IL-4的水平,以及小鼠血清中IgG抗体水平。结果显示,hfq基因大小为237 bp,编码79个氨基酸,rHFQ大约在25.8 ku处出现蛋白条带,纯化后为单一条带。Western blot结果显示,rHFQ具有较好的反应原性。rHFQ刺激RAW 264.7后,诱导IFN-γ和IL-4的水平与M5-90组相似,显著高于PBS组和pET-32a空载体组,且随着刺激时间的延长而升高。rHFQ免疫小鼠后,诱导脾细胞产生IFN-γ和IL-4的水平,小鼠血清中IgG的水平与M5-90组相似,显著高于PBS组和pET-32a空载体组。布鲁菌HFQ蛋白具有较好的反应原性,并能诱导机体产生较高的细胞免疫和体液免疫水平,是布鲁菌亚单位疫苗研制较理想的候选抗原。 相似文献
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探究猪丹毒丝菌（ER）CbpB蛋白的免疫原性和保护作用,为深入研制ER基因工程亚单位疫苗提供新的思路和技术储备。以表达的ER重组蛋白CbpB、SpaA、CbpB+SpaA以及ER灭活全菌体（V-AEr21）、商品化弱毒疫苗、商品化灭活疫苗分别免疫小鼠。利用间接ELISA检测小鼠血清中IgG抗体,血清杀菌试验测定功能性抗体水平,攻毒试验测定免疫保护率,组织荷菌数试验测定ER定植情况,并采集小鼠组织脏器（脾、肺、肝、肾）制备切片,观察病理变化。结果显示：与免疫原性最优的商品化弱毒疫苗相比,CbpB和SpaA虽产生的IgG抗体均仅为1∶6 400,但血清杀菌效果强;对小鼠的免疫攻毒保护率与商品化弱毒疫苗相同,均为100%,且在脾、肺、肝、肾组织中均无细菌定植,病理组织学观察与空白对照无明显区别。CbpB重组蛋白具有良好的免疫原性和保护作用,能刺激机体产生体液免疫和细胞免疫,可以作为猪丹毒基因工程亚单位疫苗的候选抗原。 相似文献
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用超声波破碎并采用N-十二烷基肌氨酸钠进行猪致病性大肠埃希菌外膜蛋白提取,提取物经SDS-PAGE电泳检测后制备成疫苗,以肌肉注射方式免疫SPF小鼠,于免疫前及免疫后每隔1周分别收集血清.以间接ELISA的方法检测血清中IgG抗体水平,同时用不同血清型大肠埃希菌菌株与免疫血清做玻板凝集试验和攻毒保护试验.结果表明,在免疫小鼠后的第28天左右机体内的抗体水平达到最高值,免疫血清能够与不同菌株发生凝集反应且不同菌株对小鼠的攻毒都具有免疫保护力,说明外膜蛋白不仅具有一定的免疫原性而且对不同菌株具有交叉免疫保护力,因此外膜蛋白亚单位疫苗作为一种新型疫苗可望适用于防控猪大肠杆菌病. 相似文献
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《中国兽医学报》2019,(8):1533-1539
旨在构建一种安全、高效的犬布鲁菌分子标记疫苗株。本试验将温控裂解部件(TLC)插入布鲁菌自杀质粒pBK-CMV-SacB-ΔB0419中,构建温控裂解型自杀质粒pBK-CMV-SacB-ΔB0419-TLC;通过电转化方式转入犬布鲁菌RM6/66感受态中,经卡那抗性和蔗糖培养基的正、负向筛选,将TLC片段定点插入布鲁菌B0419基因中,获得犬布鲁菌分子标记菌壳株。采用PCR法对连续30代次的菌株进行鉴定,结果显示裂解E基因和靶向插入位点区域(B0419基因)并未出现丢失和回复突变现象,表明该菌壳株具有良好的遗传稳定性。该菌壳株在培养至D_(600)值为0.6时,经42℃诱导60 h后,可获得裂解率达100%的犬布鲁菌菌壳;经超薄切片和染色处理后,在透射电镜观察下可见形态完整的空心结构,其内容物明显减少。本试验结合细菌菌壳技术与同源重组技术,成功构建了具有分子标记特征的犬布鲁菌菌壳株,为新型布鲁菌疫苗的研制提供策略。 相似文献
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Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
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Davis MS Willard MD Nelson SL Mandsager RE McKiernan BS Mansell JK Lehenbauer TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):311-314
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large. 相似文献
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Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
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Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
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The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献
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Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ 
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下载免费PDF全文 S. Pashaei T. Ghoorchi A. Yamchi 《Journal of animal physiology and animal nutrition》2016,100(2):211-216
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed. 相似文献
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Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb
albumin
- ALT
alanine aminotransferase
- AST
aspartate aminotransferase
- BUN
blood urea nitrogen
- Chol
cholesterol
- Glob
globulin
- -GT
-glutamyl transpeptidase
- IP
inorganic phosphorus
- TP
total protein 相似文献
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正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in 相似文献
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Tropical Animal Health and Production - 相似文献