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31.
本文研究了注射不同剂量的小肽对刺参体腔液中酸性磷酸酶(ACP)、碱性磷酸酶(AKP)和超氧化物歧化酶(SOD)活性及抗病力的影响。各试验组(0.2 mg组、0.4 mg组、0.6 mg组)分别注射浓度为0.4、0.8、1.2 mg/mL的小肽溶液500μL/只,对照组注射等体积无菌过滤海水。在注射后第2、4和7天,检测刺参体内ACP、AKP和SOD活性。结果表明,试验组刺参体腔液中ACP(0.4 mg组)、AKP(0.4 mg组)活性及SOD(0.6 mg组)活性分别在第4、4、7天达到最高值,与对照组相比差异均显著(P<0.05),分别为对照组的2.6、2.3、1.9倍。攻毒试验结果证实,各试验组均产生了一定的免疫保护率,0.4 mg组最大,达33.3%。结果提示,小肽作为饲料添加剂能够提高刺参的非特异性免疫水平,且注射量为0.4 mg效果最好。  相似文献   
32.
The inflammatory host response to Schistosoma bovis in young goats was studied at necropsy by light microscopy 34 weeks after primary exposure to 3,000 cercariae (group B, n=6), 34 weeks after primary exposure to 3,000 cercariae followed by challenge with 2,500 cercariae at week 17 (group C, n=5), and 17 weeks after primary exposure to 2,500 cercariae, given on week 17 of the experiment (group D, n=6). Three goats served as uninfected controls. The faecal egg output had been minimal for 17 weeks prior to necropsy in groups B and C and only for the last 2 weeks in group D.Histological studies were carried out on the small intestine, liver, lung and spleen, and tissue egg counts were performed. In sections of the small intestine and liver, a panel of histopathological variables were quantitated to characterize the host response and differences between groups of animals were evaluated with one way analysis of variance. The mean tissue egg count in the small intestine was slightly but not significantly higher in group C than group B and about twice as high in group D (D vs B or C p<0.01). Group means of numbers of inflammatory foci per section of gut wall corresponded well with those of tissue egg counts, suggesting that the rate of inflammatory destruction of eggs did not differ markedly between the groups. Egg material was less commonly seen in granulomas of the small intestine in group B than in group D (p<0.01), suggesting lower passage of eggs through the gut wall during the later than during the earlier phase of patent primary infection. The frequency of eosinophil-rich hepatic inflammatory foci was much higher in group D than in the other groups (D vs B p<0.05, D vs C p< 0.01), and coincided with a high degree of blood eosinophilia in this group at the time of sacrifice. Challenged goats showed a significantly higher frequency of markedly fibrotic inflammatory foci in the liver and of liver granulomas with a marked giant cell component than goats of the other groups. Hepatic portal fibrosis was least prominent in animals with 17- week- old primary infections, implying a possible relation between this change and duration of infection.  相似文献   
33.
Systemic mastocytosis is a rare phenomenon, with limited information regarding prognostic features and effective treatment of canine patients with this disease. The objective of this study is to determine the impact of certain features and treatments on dogs with systemic mastocytosis. The medical records of 40 dogs from 4 northeastern US veterinary hospitals, with evidence of systemic mast cell disease, were evaluated retrospectively. Variables analysed with relation to overall survival and prognostic significance included treatment protocol used, substage, presence of a cutaneous or visceral tumour, presence of multiple cutaneous Mast cell tumours, grade of the primary tumour and metastatic site(s). Dogs with metastatic disease confined to distant lymph nodes lived longer than those with circulating mast cells in the blood (P = .001), and those with metastatic disease evident in more than 2 sites had a worse prognosis than those with disease in a single location (P = .005). Additionally, administration of chemotherapeutic agents led to increased survival over prednisone therapy alone (P = .008), with the combination of lomustine, vinblastine and prednisone prolonging survival over the tyrosine kinase inhibitor, toceranib phosphate (P = .002). Presence of mast cells in the blood and/or evidence of disease in more than 2 sites indicate widespread dissemination suggesting their use as negative prognostic features. Furthermore, a chemotherapy protocol including combination lomustine and vinblastine therapy may be more effective than toceranib phosphate for the treatment of dogs with disseminated mast cell disease. Overall, patients with systemic mastocytosis have a grave prognosis and more effective treatment options are needed.  相似文献   
34.
It was the intent of this study to define which, if any, radiographic observations corresponded with specific causes of diffuse infiltrative small bowel disease and if radiographic findings could differentiate inflammatory disease from neoplastic disease and either of them from normal. Bowel spasticity, luminal narrowing, and thumbprinting tend to indicate the presence of tumor more often than inflammatory disease. Increased bowel gas in cats and barium adhesion in dogs and cats suggest that a component of enteritis is present. Decreased bowel gas in dogs is more often associated with obstructive disease, but is not helpful in differentiating diffuse inflammatory disease from diffuse neoplastic disease. While several observations that can foster differentiation of neoplastic from inflammatory disease were found, this study also indicated that the UGI lacks a high degree of predictive value other than to indicate the presence of infiltrative small bowel disease.  相似文献   
35.
Contagious bovine pleuropneumonia (CBPP) caused by Mycoplasma mycoides subsp. mycoides small colony type (MmmSC) has been eradicated in the developed world, but it is still present in many countries of sub-Saharan Africa. After initially successful control measures in the 1960s it has been spreading due to a lack of money, fragmentation of veterinary services, uncontrolled cattle movement, insufficient vaccine efficacy and sensitivity of current diagnostic tests.In this study we used two-dimensional polyacrylamide gel electrophoresis followed by immunoblot with sera from MmmSC-infected animals and MALDI-ToF mass spectrometry to identify novel immunogenic proteins as candidate molecules for improved diagnostics and vaccines. We identified 24 immunogens recognized by pooled sera from experimentally infected cattle. Furthermore, a serum from an animal with acute clinical disease as well as severe pathomorphological lesions recognized 13 additional immunogens indicating variation in the antibody responses to CBPP amongst cattle. Most immunogens showed compelling similarity to protein/gene sequences in the two ruminant pathogens M. capricolum subsp. capricolum and M. mycoides subsp. mycoides large colony type both belonging to the mycoides cluster. Three of these proteins, namely glycerol-3-phosphate oxidase, adenylosuccinate synthase, and glyceraldehyde-3-phosphate dehydrogenase, had no compelling homologue in the other distantly related bovine pathogen M. agalactiae. In addition, translation elongation factor Tu, heat shock protein 70, pyruvate dehydrogenase, and FKBP-type peptidyl-prolyl isomerase, which have been found to mediate adhesion to host tissue in other mycoplasmas were shown to be expressed and recognized by sera. These proteins have potential for the development of improved diagnostic tests and possibly vaccines.  相似文献   
36.
37.
Perforating ulceration of the small intestine was diagnosed in 5 adult horses. Affected horses presented with signs of low‐grade colic, depression and inappetance. Abdominal paracentesis yielded abnormal peritoneal fluid in all cases. Perforating ulcers were located at the mesenteric border in 4 horses and the ileum in one horse. All horses had diffuse septic peritonitis. The aetiology of the condition is unknown.  相似文献   
38.
39.
本文采用短乳杆菌、酵母菌、枯草芽孢杆菌和地表芽孢杆菌进行豆粕固态限定发酵和强化发酵的研究,对发酵过程中小分子蛋白含量、菌量、pH及胰蛋白酶抑制剂活性等进行了测定.结果表明:纯菌条件下,接种短乳杆菌和地衣芽孢杆菌实验组限定发酵的小分子蛋白含量分别为31.0%和28.3%,高于接种酵母菌试验组的22.4%.且小分子蛋白积累高峰时间为48~72 h;接种地表芽孢杆菌实验组的胰蛋白酶抑制剂降解率高于接种短乳杆菌或酵母菌实验组.豆粕天然发酵试验组的小分子蛋白含量和胰蛋白酶抑制剂降解率分别为22.2%和44.1%.接种短乳杆菌、地衣芽孢杆菌试验组的小分子蛋白含量和胰蛋白酶抑制剂降解率分别为32.4%、99.5%和29.3%、99.7%.表明接种强化发酵有助于小分子蛋白含量的提高和胰蛋白酶抑制剂的降解.  相似文献   
40.
Background: According to international recommendations, reference intervals should be determined from at least 120 reference individuals, which often are impossible to achieve in veterinary clinical pathology, especially for wild animals. When only a small number of reference subjects is available, the possible bias cannot be known and the normality of the distribution cannot be evaluated. A comparison of reference intervals estimated by different methods could be helpful. Objective: The purpose of this study was to compare reference limits determined from a large set of canine plasma creatinine reference values, and large subsets of this data, with estimates obtained from small samples selected randomly. Methods: Twenty sets each of 120 and 27 samples were randomly selected from a set of 1439 plasma creatinine results obtained from healthy dogs in another study. Reference intervals for the whole sample and for the large samples were determined by a nonparametric method. The estimated reference limits for the small samples were minimum and maximum, mean ± 2 SD of native and Box–Cox‐transformed values, 2.5th and 97.5th percentiles by a robust method on native and Box–Cox‐transformed values, and estimates from diagrams of cumulative distribution functions. Results: The whole sample had a heavily skewed distribution, which approached Gaussian after Box–Cox transformation. The reference limits estimated from small samples were highly variable. The closest estimates to the 1439‐result reference interval for 27‐result subsamples were obtained by both parametric and robust methods after Box–Cox transformation but were grossly erroneous in some cases. Conclusion: For small samples, it is recommended that all values be reported graphically in a dot plot or histogram and that estimates of the reference limits be compared using different methods.  相似文献   
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