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1.
将共表达鸡传染性支气管炎病毒(IBV)SI基因和鸡干扰素.丫基因的重组鸡痘病毒(rFPV-IFNγ S1)接种4周龄SPF鸡,免疫3周后用同源(LX4株)及异源强毒株(LTJ951)攻毒,评价重组疫苗对异源病毒的保护作用.结果显示,重组疫苗接种1周后,免疫鸡产生抗IBV的抗体;而且外周血中CD4+和CD8+T淋巴细胞的含量略高于非免疫对照组;攻毒后,异源强毒株攻毒的免疫组CD4+T淋巴细胞呈下降趋势,并且该组低水平CD4+的状态一直持续到试验结束,而其他组CD4+T淋巴细胞均迅速上升,峰值达到14.5%;同源强毒株攻毒的免疫组CD8+T淋巴细胞呈高水平的表达,而其他组攻毒后均无明显变化;保护率结果显示,同源强毒株攻毒免疫组的发病率和死亡率为21.43%和0%,与其他各组相比均有显著差异;另外同源强毒株攻毒的免疫组病理损伤与异源强毒株攻毒的试验组相比明显减轻,其排毒时间和排毒量也均有所减少;强毒攻毒后所有试验组体重无显著差异.以上结果可以说明,重组疫苗能对同源强毒株产生较好的免疫保护,但不能对遗传关系较远的强毒株产生有效的免疫应答.  相似文献   

2.
将共表达鸡传染性支气管炎病毒(mv)S1基因和鸡干扰素-γ基因的重组鸡痘病毒(rFPV—IFN-γ S1)接种4周龄SPF鸡,免疫3周后用同源(LX4株)及异源强毒株(LTJ95I)攻毒,评价重组疫苗对异源病毒的保护作用。结果显示,重组疫苗接种1周后,免疫鸡产生抗IBV的抗体;而且外周血中CD4^+和CD8^+T淋巴细胞的含量略高于非免疫对照组;攻毒后,异源强毒株攻毒的免疫组CD4^+T淋巴细胞呈下降趋势,并且该组低水平CD4^+的状态一直持续到试验结束,而其他组CD4^+T淋巴细胞均迅速上升,峰值达到14.5%;同源强毒株攻毒的免疫组CD8^+T淋巴细胞呈高水平的表达,而其他组攻毒后均无明显变化;保护率结果显示,同源强毒株攻毒免疫组的发病率和死亡率为21.43%和0%,与其他各组相比均有显著差异;另外同源强毒株攻毒的免疫组病理损伤与异源强毒株攻毒的试验组相比明显减轻,其排毒时间和排毒量也均有所减少;强毒攻毒后所有试验组体重无显著差异。以上结果可以说明,重组疫苗能对同源强毒株产生较好的免疫保护,但不能对遗传关系较远的强毒株产生有效的免疫应答。  相似文献   

3.
为研制鸡球虫早熟系疫苗,探讨早熟系诱导的细胞介导免疫机理,实验采用流式细胞仪(FACS)检测堆型艾美球虫早熟株免疫雏鸡后,在不同时间外周血T淋巴细胞亚群CD4 T和CD8 T的动态变化。试验结果表明,免疫组CD4 T数量动态变化显著高于不免攻毒组(P<0.05),免疫后16天达到高峰;不免攻毒组攻毒后上升速度较快,于攻毒后1周达到高峰。CD4 T的数量变化,说明它在启动细胞免疫应答和控制再次感染中发挥着作用。免疫组CD8 T数量动态变化亦显著高于不免攻毒组(P<0.05),免疫组和不免攻毒组CD8 T数量均在攻毒后1周达到最大值,表明CD8 T在抵抗感染中起作用。各组间CD4 T/CD8 T比值无明显差异,但免疫组CD4 T/CD8 T变化较为平缓。上述堆型艾美球虫早熟系免疫雏鸡后,CD4 T和CD8 T在不同时间数量的增减及其比值的变化,将为早熟系疫苗在生产实践中的合理使用提供理论依据。  相似文献   

4.
采用免疫荧光法、使用流式细胞检测仪对经H9亚型禽流感病毒人工感染SPF鸡、H9亚型禽流感油乳剂灭活苗免疫SPF鸡以及经免疫后使用H9亚型禽流感病毒攻毒后的SPF鸡外周血、脾脏、胸腺中T细胞表型亚类(CD4+、CD8+、TCR1+)的变化规律进行了监测,结果表明,H9亚型禽流感油乳剂灭活苗免疫后抗原的缓慢释放可在一定程度上激发机体的细胞免疫应答,使免疫活性T淋巴细胞得到活化,免疫后鸡体外周血中CD4+、CD8+和TCR1+T细胞的数量呈现出一明显升高的过程;同时,人工感染免疫鸡后,脾脏和胸腺TCR1+T细胞的数量上升,外周血CD4+、CD8+和TCR1+T细胞的数量少量降低或维持不变,随后短期即恢复正常;而人工感染SPF对照鸡后,外周血CD4+、CD8+和TCR1+T细胞的数量呈现下降趋势.  相似文献   

5.
将重组鸡痘病毒(rFPV—IFN-γ)与IBDMB43弱毒疫苗联合接种SPF鸡,研究重组鸡IFN-γ对IBD疫苗免疫效果的影响。结果显示,rFPV—IFN-γ和MB43弱毒疫苗联合免疫组(MB43+rFPV-IFN-)")及rlFN-γ和MB43弱毒疫苗联合免疫组(MB43+rIFN-γ)在免疫后第2周即可检出ELISA抗体,比MB43疫苗单独免疫组早1周。用IBDVGx株攻击后,MB43+rFPV-IFN-γ组和MB43+rIFN-γ组免疫鸡的脾只有个别淋巴细胞核浓缩、核崩解,少数滤泡萎缩变性坏死;胸腺损伤程度轻于MB43疫苗单独免疫组和非免疫对照组。免疫后1周,3个免疫组外周血CD8^+T淋巴细胞含量均显著高于非免疫对照组,CD4^+T淋巴细胞含量变化不明显;攻毒后第2周,3个疫苗免疫组CD4^+、CD8^+T淋巴细胞含量均显著升高,各组之间CD4^+、CD8^+T淋巴细胞含量无明显差异。证实,rFPV—IFN-γ和rIFN-γ可加强疫苗的细胞免疫和体液免疫应答。  相似文献   

6.
140只黄羽肉鸡随机分为6组,除空白组外,分别于10日龄和20日龄时每只鸡以3000、5000个柔嫩艾美耳球虫卵囊免疫,其中各用药组于首免时及24,29,31日龄胸部皮下注射牛膝皂苷(Achyranthes Bidentata Saponin,ABS)1次,30日龄时以6万卵囊攻毒,并于攻毒前后各用药1次。分别于18,25,32,39日龄采血。通过MTT法测定淋巴细胞转化水平,流式细胞技术检测外周血CD4+、CD8+T淋巴细胞亚群数量的动态变化,并检测了不同时期试验鸡增重及脾指数变化情况。结果表明:ABS能够提高球虫免疫鸡的淋巴细胞转化水平,升高CD4+/CD8+T淋巴细胞亚群比值,这提示注射用ABS能够促进球虫免疫鸡的免疫机能。  相似文献   

7.
rFPV-IFNγS1是一株共表达传染性支气管炎病毒S1基因和鸡干扰素-γ基因的重组鸡痘病毒,将其接种SPF鸡3周后,用传染性支气管炎病毒异源毒株LTJ95I攻击.结果显示,疫苗接种后1周,免疫鸡血清抗体很快产生,外周血中CD4 和CD8 T淋巴细胞的百分含量略高于非免疫对照组,但这种差异并不显著.攻毒后保护率结果显示,该疫苗不能对异源病毒提供坚强保护,攻毒后免疫组的发病率为6O%(6/10),病死率为30%(3/10),非免疫对照组的发病率和病死率分别为73%(8/11)和27%(3/11);两组的病理损伤程度差异不明显,在排毒时间上也没有明显变化.  相似文献   

8.
对牛流行热病毒灭活疫苗免疫并攻每后,牛外周血淋巴细胞亚类的变化进行了研究。结果表明,灭活苗免疫后,牛的CD4^ 显著升高,可能与参与辅助B淋巴细胞合成抗体有关,攻毒后,γδT细胞均显著上升,免疫组在攻毒后3周仍保持在相当的高水平,IL-2Rα阳性细胞在攻毒后高热期也有显著升高,而CD8^ 细胞没有明显变化。  相似文献   

9.
用改进水提醇沉法提取银杏叶多糖。用灭活的传染性法氏囊超强毒(vvIBDV)GX8/99细胞适应株分别制备不同质量浓度(40,20,10 g/L)银杏叶多糖佐剂疫苗、弗氏不完全佐剂疫苗和无佐剂疫苗。360只SPF公雏鸡随机均分为6组,其中5组SPF鸡分别免疫上述5种疫苗,另外1组SPF鸡不免疫作为阴性对照。检测IL-2和IFN-γ分泌量、血清抗体、外周血淋巴细胞转化率、外周血CD4^+和CD8^+T淋巴细胞数量等用来评价疫苗的免疫效果。38日龄进行攻毒试验,评价疫苗的保护效果。结果显示,银杏叶多糖佐剂疫苗组各免疫指标均显著高于弗氏佐剂和无佐剂疫苗组(P<0.05);40 g/L银杏叶多糖佐剂疫苗组免疫效果最好,但与20 g/L银杏叶多糖佐剂疫苗组差异不明显,并且2组攻毒保护率无显著性差异。结果表明,银杏叶多糖作为vvIBDV疫苗佐剂具有良好的免疫促进作用,且20 g/L的银杏叶多糖即可达到最佳效果。  相似文献   

10.
IBV M基因与IL-18基因共表达DNA疫苗的免疫原性   总被引:1,自引:0,他引:1  
将禽传染性支气管炎病毒(IBV)的M基因和禽白介素18(IL-18)基因分别插入双顺反子质粒pIRES-EGFP/DsRed中,构建IBV M和IL-18基因的共表达质粒pIRES-M/IL18及表达M基因的pIRES-M质粒。通过脂质体转染Vero细胞,利用RT-PCR及间接免疫荧光检测质粒在体外的表达。将构建的质粒用脂质体包裹后,通过腿部肌肉多点注射免疫7日龄雏鸡,28日龄加强免疫1次;免疫前后均采血检测ELISA抗体效价和外周血CD3+、CD4+、CD8+T淋巴细胞的数量;二免后2周用IBV肾型强毒进行攻毒。结果显示,pIRES-M/IL18、pIRES-M质粒均在Vero细胞中有效地转录并表达目的蛋白。从免疫后7 d起,pIRES-M/IL18免疫组产生的抗体水平及外周血T淋巴细胞亚群数量均高于pIRES-M组。pIRES-M/IL18、pIRES-M组对强毒的攻击保护率分别为65%和40%。以上结果表明,禽源IL-18基因与IBV M基因共表达可增强鸡体对DNA疫苗的免疫应答,提高对IBV强毒的抵抗力。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
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   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
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   

17.
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   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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