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1.
A reference interval for plasma glutamate dehydrogenase (GD) (E.C. 1.4.1.3) activity, of 0-8 IU/L, was established for the cockatiel (Nymphicus hollandicus). An automated modification of a commercial manual assay was used. This enzyme is considered liver specific in humans and numerous domestic animals, due to its organ distribution. A similar distribution was found in cockatiels in this study. Maximal enzyme activity was recovered from liver and kidney homogenate supernatants. Minimal activity was detected in skeletal muscle preparations. These results suggest a potential use for plasma GD activity in the evaluation of hepatocelluar injury/necrosis in cockatiels.  相似文献   
2.
The immune response of pigs fed 200 mg per day of dinitrophenylated bovine gamma globulin has been evaluated in terms of the antibody and lymphocyte responses and of the induction of tolerance and immune exclusion. Although dosing for ten days resulted in a small IgA response as indicated by splenic plaque forming cells, serum antibody could only be detected when dosing was continued for 42 days. secretory antibody was detected at any time. Antigen feeding for two weeks rendered the animals hyporesponsive to subsequent parenteral antigenic challenge but had little effect upon their ability to exclude an oral dose of antigen from the circulation.  相似文献   
3.
Bryozoology     
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4.
Heart rate and behaviour during and following velvet antler removal were monitored in yearling red deer stags to determine the extent to which this procedure was perceived by the deer to be aversive. Nine stags normally kept at pasture were habituated over 5 weeks to the following daily handling procedure. Each deer was fitted with a harness containing a heart rate monitor. It was then allowed to run through a fixed course in a deer yard, restrained for 40 s in a mechanical deer crush, and then confined for 3.5 h with the remainder of the group of stags in an indoor pen containing food and water. In Week 6, the deer were subjected to either restraint for 6 minutes (the control treatment) or removal of one velvet antler under local anaesthesia. Each velvet antler was removed on separate occasions, either on Days 1 and 2 (five deer) or Days 3 and 4 (four deer). The control treatment was applied to all deer when velvet antler was not being removed, and on Day 5. Heart rate and behaviour (time taken to enter the treatment area, and number of struggles made during restraint) were measured before and during treatment, and post-treatment activities were recorded at 0, 1 and 3 h (indoors), and at 6 and 9 h (at pasture). Heart rate was higher during the second velvet antler removal treatment than during the first, but lower during the second control treatment than the first (P<0.05). During velvet antler removal, stags struggled more, and after the treatment flicked their ears, shook their heads, and groomed themselves more than control stags (P<0.05). Stags whose velvet antler had been removed spent less time eating than control stags, and spent progressively more time sitting during the 3.5 h of confinement (P<0.05). However, during the paddock observation at 9 h post-treatment, stags which had had their velvet antler removed grazed more than control stags (P<0.05). The increase in heart rate over the two velvet antler removal treatments and the greater amount of struggling during velvet antler removal indicated that it was more aversive than the control treatment. Post-treatment differences in behaviour may have been due to pain following velvet antler removal.  相似文献   
5.
6.
Infectious bronchitis (IB) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (MHC) B complex genotypes. MHC B genotypes were determined by DNA sequence-based typing of BF2 alleles. In total, 33 B2/B15 and 47 B2/B21 chickens were vaccinated with an Ark-type IB virus (IBV) attenuated vaccine and challenged with Ark-type IBV field isolate AL/4614/98 14 days later. Additional chickens of both genotypes served as unvaccinated/challenged and unvaccinated/nonchallenged controls. Clinical signs, histopathologic analysis, detection of IBV genomes in tears, and IBV-specific immunoglobulin A (IgA) in tears were used to evaluate disease progression and immune response. The incidence of IBV respiratory signs was significantly higher in B2/21 than in B2/B15 MHC genotype birds. However, neither the severity and duration of respiratory signs nor the severity and incidence of histologic lesions differed significantly with MHC genotype. The levels of IBV-specific IgA in tears of vaccinated and challenged chickens did not differ significantly between MHC genotypes. IBV genomes were present in the tears of vaccinated and challenged birds, and the incidence of detectable IBV genomes did not vary significantly with MHC B genotype. From an applied perspective, these results indicate that vaccinated commercial outbred chickens with these MHC genotypes are equally resistant to IBV.  相似文献   
7.
The renal pathology and urinary protein pattern of a 14-month-old female Bernese mountain dog with chronic renal failure was investigated. Sodium dodecyl sulphate-polyacrylamid gel electrophoresis and subsequent Western blot analysis of urine showed the presence of heavy and light chains of immunoglobulin, transferrin, albumin, vitamin D-binding protein, transthyretin and retinol-binding protein (RBP), but no excretion of Tamm-Horsfall protein (THP). Histopathological examinations of the kidneys revealed severe membranous glomerulonephritis accompanied by tubular dilatation, tubular atrophy and interstitial fibrosis. The renal expression of megalin, the main endocytic receptor for the re-uptake of proteins in proximal tubules, RBP and THP was reduced or completely absent, indicating severe tubular dysfunction. The identified urinary proteins may be of interest as additional markers for the diagnosis of juvenile nephropathy in Bernese mountain dogs.  相似文献   
8.
转兔角蛋白基因改良棉纤维品质研究   总被引:10,自引:5,他引:10  
通过花粉管通道转基因技术,将E6启动子驱动的兔角蛋白基因导入高产棉花品种苏棉16号。所用转基因表达载体还含有选择标记基因NPTⅡ(卡那霉素抗性基因)及Gus报告基因。对转化体后代的检测结果表明,T1代有2.1%呈现Gus阳性,在Gus阳性株中84.6%具有卡那霉素抗性。用依据E6启动子序列和兔角蛋白基因序列设计的两对引物,对经过上述筛选的植株进行PCR检测,多次重复,最终确定3株结果稳定的转兔角蛋白基因棉株。从品质分析结果看,这3个株系成熟棉纤维的品质部分得到改良,尤其比强度有较大幅度提高,与转基因受体相比平均提高6.3cN·tex 1。  相似文献   
9.
双价抗虫转基因棉花研究   总被引:167,自引:9,他引:167  
构建了携带人工合成的GFM CryIA杀虫基因和经过修饰的CpTI基因的高效双价杀虫基因植物表达载体pGBI121S4ABC。采用花粉管通道法,将pGBI121S4ABC转入到石远321、中棉所19号、3517和541中国棉花生产品种中,首次获得了双价转基因抗虫棉株系。叶片室内抗虫生物学鉴定表明,抗性好的株系棉铃虫幼虫校正死亡率大于96%;经分子检测,证实了双价杀虫基因在棉花基因组中的整合与表达。  相似文献   
10.
转蚕丝芯蛋白基因获得高强纤维棉花植株   总被引:9,自引:0,他引:9  
采用花粉管通道技术,将棉纤维细胞特异表达启动子(E6)驱动的蚕丝芯蛋白基因导入陆地棉品种"泗棉3号"。共注射600朵花,收获497粒种子。通过GUS报告基因组化检测筛选,获得5株GUS阳性棉株。又经卡那霉素涂叶法鉴定,其中4株具有良好的卡那霉素抗性。用依据E6启动子序列和蚕丝芯蛋白基因序列设计的两对引物,对这5株棉花进行PCR扩增,获得1株转蚕丝芯蛋白基因棉株。纤维品质测定结果表明,这株转蚕丝芯蛋白基因棉花T1代纤维比强度达到34.6cN/tex,比对照"泗棉3号"(比强度为28.6cN/tex)提高了21.0%,T2代纤维比强度比对照平均增高23.3%。  相似文献   
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