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排序方式: 共有347条查询结果,搜索用时 15 毫秒
91.
本研究采用AGP、HI等试验方法,对经H9亚型禽流感油乳剂灭活苗免疫、免疫后攻毒以及经H9N2活毒人工感染后的SPF鸡抗体产生、消长规律进行了测定,结果表明人工感染SPF鸡和免疫鸡一周后,AGP的检出率即可达到100%;H9亚型禽流感油乳剂灭活苗自免疫后一周内即可产生HI抗体,21-28天达到高峰,并能对相同亚型病毒感染引发良好的免疫反应。  相似文献   
92.
以RPV-H为种毒,按2×10~(-2)接毒量,采用同步接毒的方法,接于猫肾细胞系F_(65)株,于37℃静置培养,待细胞病变(CPE)达到75%以上时,开始收获。经甲醛灭活24h,即为RPV-H细胞培养灭活疫苗。给貉皮下接种2ml/只,间隔14天进行第2次加强免疫,21天可产生免疫力,免疫期可达180天。RPV-H细胞灭活苗10ml给貉皮下接种,无任何不良反应,具有安全性,免疫效果良好。  相似文献   
93.
在结扎子宫颈的情况下,在同一子宫的两侧子宫角分别注入生理盐水(对照组)和精液(试验组)以研究精液对子宫免疫和孕向发育的影响。试验共用母兔8只。子宫注入后48 h处死试验用兔,取子宫进行测量,并制片染色,用图像采集分析系统进行研究。结果显示:1)与对照组相比,兔子宫注入精液后可以显著(P〈0.05)增加子宫的长度、直径和子宫角指数;可明显增加子宫壁(P〈0.05)、黏膜上皮层(P〈0.01)和黏膜层(P〈0.05)的厚度;可显著增加黏膜中腺管(P〈0.05)和血管(P〈0.05)数量,可明显增加腺上皮的厚度(P〈0.05)。2)子宫注入精液后,子宫冲洗液中的细胞数(53.3±4.03×109/L)较对照组极显著增加(P〈0.01);单位面积子宫黏膜中肥大细胞的数量(2.85±0.05个/mm2)较对照组(3.72±0.04个/mm2)显著减少(P〈0.05)。子宫冲洗液涂片染色检查发现,子宫冲洗液中的细胞主要为嗜中性粒细胞。本研究表明,兔精液确实能够促进母兔子宫的孕向发育,能够改变子宫的免疫状态。  相似文献   
94.
Dermanyssus gallinae is the most significant ectoparasite of European poultry egg laying production systems due to high costs of control and associated production losses as well as adverse effects on bird welfare. In this study, soluble proteins were extracted from unfed D. gallinae (DGE) using a urea-based detergent and ultra-filtration, passed through a 0.22 μm filter and blended aseptically with adjuvant. One group of laying hens was immunized with DGE and adjuvant (Montanide ISA 50 V) whilst another group (Control) received physiological saline and adjuvant. All birds were immunized on two occasions, 21 days apart. Antibody response to immunization was determined by ELISA and western blotting using immunoglobulins (Igs) extracted from egg yolk. DGE immunization of hens resulted in a significant (P < 0.05) IgY response compared to controls, although there was no significant difference in IgM response between treatments. A number of proteins were identified by western blotting using IgY antibodies from DGE immunized birds, most prominently at 40 and 230 kDa. Analysis of proteins from approximately corresponding bands on SDS-PAGE confirmed the identity of tropomyosin, whilst other proteins showed high sequence homology with myosin and actin from other arachnid and insect species. Immunization of hens with DGE resulted in a 50.6% increase in mite mortality (P < 0.001) 17 h after feeding when tested by an in vitro mite feeding model. Data in this study demonstrate that somatic antigens from D. gallinae can be used to stimulate a protective immune response in laying hens. Further work is needed to identify other proteins of interest that could confer higher protection against D. gallinae, as well as optimization of the vaccination and in vitro testing protocol.  相似文献   
95.
丹顶鹤、黑鹳等属世界珍稀鸟类物种,为我国I级保护动物,现已确认鹤、鹳等可以患鸟类的烈性、毁灭性传染病——新城疫。鉴于国内外鹤、鹳新城疫防疫与检测没有系统的研究报道,尚没有一个完整可靠的科学依据来指导防疫程序。本研究采用血凝抑制试验(HI)测定接种新城疫疫苗前后的鹤、鹳,观察其血清抗体效价的消长规律,认定其免疫能力。支持和指导鹤、鹳防疫程序的建立。  相似文献   
96.
An experiment was conducted on 30 male Nellore lambs with average body weight (BW) of 15.45 +/- 0.06 kg to determine the level of the copper (Cu) supplementation in diet from inorganic and organic sources required for optimum immunity and its effect on copper dependent enzymes by allotting them randomly to five groups in completely randomized design. The dietary treatments were viz., basal diet (no Cu supplementation, BD), other four groups were offered BD supplemented with 7 or 14 ppm Cu from copper sulphate (CuSO(4)) and Cu-proteinate, respectively. The lambs were fed the respective diets at 3.5 per cent BW to meet the requirements except Cu for 180 days. The humoral immune response against Brucella abortus and chicken RBC was assessed after 90 days of feeding. The in vivo delayed type hyper sensitivity reaction against PHA-P and in vitro lymphocyte proliferation against Con A indicative of cell mediated immune response (CMI) was assayed at 180 days of feeding. At the end of experiment four lambs from each group were slaughtered for estimation of liver superoxide dismutase activity (SOD). The ceruloplasmin and RBC-SOD activities were higher (P < 0.05) in 14 ppm Cu supplemented lambs from Cu-proteinate at 90 and 180 days, while the liver SOD activity was higher (P < 0.05) in lambs fed 14 ppm Cu from CuSO(4). The STAT titres against B. abortus were higher in Cu supplemented lambs, with no effect of dose of supplementation. Lambs supplemented with Cu-proteinate had higher titers than CuSO(4) on 7 and 14 days of post sensitization. The total immunoglobulin concentration and the CMI response against PHA-P and Con-A was higher (P < 0.05) in lambs fed 14 ppm Cu-proteinae diet. The IgM level was though high in Cu supplemented lambs, no dose or source effect were observed. The study indicated that Cu dependent enzymes activity and immune response were highest and respond better against stress in lambs on 14 ppm supplemented Cu from Cu-proteinate.  相似文献   
97.
将微生态制剂添加到基础日粮中饲喂初生樱桃谷肉鸭,于14日龄、21日龄、35日龄、42日龄时采血检测红细胞C3b受体花环(E-C3bR)率、红细胞免疫复合物花环(E-ICR)率和外周血T淋巴细胞,然后屠宰取脾脏、胸腺、法氏囊测定免疫器官指数.试验结果证明,14、21、35、42日龄试验组红细胞C3b受体花环(E-C3bR)率分别为17.09±0.36、16.12±0.39、15.27±0.46、15.35±0.30(分别比对照组高出6.28%、7.83%、8.99%和6.15%),红细胞免疫复合物花环(E-ICR)率分别为11.15±0.34、10.08±0.37、9.96±0.39和9.33±0.23(分别比对照组高出8.36%、12.25%、10.91%和10.28%).采用酸性α-醋酸萘酯酶(ANAE+)染色法.对四个相同日龄段鸭的外周血T淋巴细胞检测数量分别为57.18±0.71、66.52±0.51、69.66±0.57和71.92±0.51(分别高出对照组5.56%、8.27%、3.09%和5.04%).21日龄时试验组的胸腺指数、脾脏指数、法氏囊指数分别为6.15±0.15、1.14±0.06和1.73±0.07(分别高出对照组14.10%、13.07%和14.00%),42日龄时试验组分别为3.82±0.06、0.96±0.05和0.88±0.09(分别高出对照组25.26%、15.66%和35.38%).本研究结果显示,微生态制剂可以促进肉鸭免疫器官的生长发育,提高樱桃谷肉鸭的免疫器官指数,进而提高鸭群的特异性和非特异性免疫能力.  相似文献   
98.
HU Chao-feng 《园艺学报》2004,20(7):1304-1308
Nucleotide-binding oligomerization domain (NOD) proteins are members of a growing family of cytosolic factors related to the apoptosis regulator Apaf-1 and a class of plant disease resistance proteins. NOD proteins have been implicated in the induction of NF-κB activity and in the activation of caspases. Biochemical evidence has unraveled the role of NOD1 and NOD2 as intracellular sensors of bacterial peptidoglycan. Notably, genetic variation in the genes encoding the NOD proteins NOD2, cryopyrin and CⅡTA in humans is associated with inflammatory disease or increased susceptibility to bacterial infections. NOD proteins may be involved in the recognition of microorganisms and regulation of inflammatory responses.  相似文献   
99.
饲料维生素A对美国红鱼生长和免疫的影响   总被引:1,自引:0,他引:1  
本试验旨在研究饲料维生素A对美国红鱼生长(增重率、特定生长率、存活率和饲料效率)和免疫反应相关指标(血清中溶菌酶活性、超氧化物歧化酶活性和总补体活性)的影响.采用单因子试验设计,将300尾平均体重为(151.46±8.18)g的美国红鱼随机分为5个处理,每个处理设3个重复,每个重复20尾,分别饲喂5种不同VA水平(30、4 166、8 533、18 532、33 263 IU/kg)的等氮等能饲料,进行为期8周的生长试验.结果表明:饲料中VA水平为30 IU/kg时其增重率、饲料效率、特定生长率、成活率均显著低于4 166、8 533、18 532 IU/kg组(P<0.05),VA水平为33 263 IU/kg时各指标有所降低.其中饲料效率和特定生长率显著低于4 166、8 533、18 532 IU/kg组(P<0.05);VA水平为30 IU/kg时血清溶菌酶活性,SOD活性和总补体活性显著低于其他组(P<0.05),VA水平在18 532 IU/kg时血清溶菌酶活性达到最高值,其次为33 263、8 533、4 166 IU/kg组;VA水平在8 533 IU/kg时血清SOD和总补体活性达到最高值,并显著高于4 166、18 532、33 263IU/kg组(P<0.05).综上所述,饲料中适宜VA水平能显著促进美国红鱼生长、提高相关免疫力,且饲料VA水平为8 533 IU/kg时对美国红鱼生长和免疫相关指标影响较显著.  相似文献   
100.
To evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes, vitamins and immune functions affected by copper deficiency, and to identify the parameters which can be of diagnostic importance in copper deficiency, a survey was conducted in 12 districts of Northern India. Significant deficiency of copper was observed in soil, fodder and serum samples of buffalo heifers. Fifty hypocuperaemic buffalo heifers were selected from these areas and were randomly divided into two groups, A and B. The heifers in group A were provided with mineral mixture containing copper sulphate and in group B without copper sulphate. Significant (p < 0.01) improvement in serum ceruloplasmin level was observed within 30 days of treatment, while significant (p < 0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group A animals. Significant improvement was observed in T3 and T4, in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (p < 0.01) improvement within 30 days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (p < 0.01) improved in group A within 60 days of treatment. Similarly, significant improvement in superoxide dismutase activity in red blood cells was observed at the 30th day, and in total leukocytes and whole blood at the 60th day in group A animals. Significant improvement in liver copper level was observed at the 30th day of treatment, while in group B the liver copper was significantly (p < 0.01) depleted at the 60th day of experimentation. Additional copper supplementation improved growth performance significantly in group A.  相似文献   
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