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排序方式: 共有210条查询结果,搜索用时 171 毫秒
41.
Mycobacterium avium subsp. paratuberculosis (MAP) is a slow growing bacterium that can infect ruminants and remain latent for years without development of any clinical signs or disease. Diagnosis is often based on detection of MAP antibodies in milk or serum samples or culture of bacteria from faeces; however, these diagnostic tools are often not applicable until years after infection. Detection of MAP specific cell-mediated immune (CMI) responses can serve as an alternative and be implemented in a diagnostic tool. CMI responses can be measured at an early stage of infection, prior to development of antibodies and shedding of detectable amounts of MAP. At present, available diagnostic assays are limited by the lack of MAP specific antigens included in these assays resulting in poor specificity. The objective of this review is to provide a systematic overview of diagnostic MAP antigen candidates described to date with special emphasis on antigen candidates tested for CMI responses. Relevant information on 115 different MAP antigens was systematically extracted from literature and summarized in 6 tables of CMI antigens, secreted antigens, cell wall and membrane antigens, lipoprotein antigens, heat shock antigens and hypothetical antigens. Strategies for evaluation of novel antigen candidates are discussed critically. Relatively few of the described antigens were evaluated for their use in CMI based diagnostic assays and so far, no obvious candidate has been identified for this application. Most of the novel diagnostic candidates were evaluated in few animals and it is recommended that an appropriate sample size is included for evaluation of antigen candidates in future studies. 相似文献
42.
Heidrun Gehlen Sophie Twickel Sabita Stöckle Corinna Weber Claus P. Bartmann 《Journal of animal physiology and animal nutrition》2020,104(2):679-689
Pituitary pars intermedia dysfunction is the most prevalent endocrine disease in horses. Although donkeys and mules may also be affected, only a few data have been published. Reference values for diagnostic parameters, such as adrenocorticotropic hormone (ACTH), are especially scarce or even lacking. Therefore, in the present study, available data from the literature have been verified and completed to facilitate a reliable diagnosis. Clinical inspections and haematological and biochemical examinations were carried out four times in a three-month interval (February to November) in 44 donkeys and 31 mules. Data from clinically healthy animals were used as an orientation. Plasma ACTH concentrations showed seasonal changes in both animal groups. However, it was generally higher in donkeys than mules. Although blood glucose (EDTA plasma) showed no difference between groups, serum insulin concentrations were consistently higher in donkeys. Serum fructosamine levels were slightly higher in mules, whereas, in some cases, serum triglyceride levels were considerably higher in donkeys. Serum gamma-glutamyltransferase showed a striking peak in mules in August, whereas the remaining gamma-glutamyltransferase values were lower compared to donkeys. By comparing donkeys and mules, the present work reveals differences in various blood parameters which should be considered for diagnoses and future studies. 相似文献
43.
Progesterone profiles were measured in milk fat of 12 goats (Deutsche Bunte Edelziege) from kidding until a new pregnancy. The goats were kept under natural light conditions without bucks. Eight of the does started to cycle from August until October without a progesterone rise in the preceding period. Three does exhibited one single luteal phase in March and resumed cycling in July and August. The occurrence of a normal corpus luteum was typically preceded by a transient progesterone “spike” in 10 out of the 12 goats. One goat additionally showed several “spikes” in June and July; normal luteal function, however, started in September. With one exception oestrus symptoms were never observed without a preceding progesterone rise. 相似文献
44.
Weber B Hartmann B Stöckigt D Schreiber K Roloff M Bertram HJ Schmidt CO 《Journal of agricultural and food chemistry》2006,54(2):274-278
Liquid chromatography/mass spectrometry and liquid chromatography/nuclear magnetic resonance techniques with ultraviolet/diode array detection were used as complementary analytical tools for the reliable identification of polymethoxylated flavones in residues from molecular distillation of cold-pressed peel oils of Citrus sinensis. After development of a liquid chromatographic separation procedure, the presence of several polymethoxy flavones such as sinensetin, nobiletin, tangeretin, quercetogetin, heptamethoxyflavone, and other derivatives was unambiguously confirmed. In addition, proceranone, an acetylated tetranortriterpenoid with limonoid structure, was identified for the first time in citrus. 相似文献
45.
By means of a cost benefit analysis, we compare public and private incentives to invest in extensive green roofs in urban areas. From the comparison of these public and private incentives we find that subsidies for green roofs are socially desirable and that subsidies are actually needed to convince potential private investors to construct green roofs. Specifically, we estimate the costs and benefits associated with an investment project in Dilbeek (Belgium) where a real estate investor considers the construction of an extensive green roof on an office building. 相似文献
46.
Buescher JM Liebermeister W Jules M Uhr M Muntel J Botella E Hessling B Kleijn RJ Le Chat L Lecointe F Mäder U Nicolas P Piersma S Rügheimer F Becher D Bessieres P Bidnenko E Denham EL Dervyn E Devine KM Doherty G Drulhe S Felicori L Fogg MJ Goelzer A Hansen A Harwood CR Hecker M Hubner S Hultschig C Jarmer H Klipp E Leduc A Lewis P Molina F Noirot P Peres S Pigeonneau N Pohl S Rasmussen S Rinn B Schaffer M Schnidder J Schwikowski B Van Dijl JM Veiga P Walsh S Wilkinson AJ Stelling J Aymerich S 《Science (New York, N.Y.)》2012,335(6072):1099-1103
47.
Dominik Burger DVM Claus Wedekind Bettina WespiIsabel Imboden DVM Sabine Meinecke-Tillmann Harald Sieme 《Journal of Equine Veterinary Science》2012
The reproductive efficiency of stabled domestic stallions is often lower than what could be expected from observations in feral herds. In the wild, stallions typically live with mares in harem bands, with other stallions in bachelor bands, or occasionally in mixed-sex transitional bands. We, therefore, argue that permanent contact with mares may increase reproductive efficiency of stallions suffering from low libido and/or fertility. We also provide a summary of our present knowledge of natural conditions, management, and husbandry of domestic stallions, and of intra- and intersexual behavioral interactions in horses. 相似文献
48.
Association between CARD15/NOD2 gene polymorphisms and paratuberculosis infection in cattle 总被引:1,自引:0,他引:1
Pinedo PJ Buergelt CD Donovan GA Melendez P Morel L Wu R Langaee TY Rae DO 《Veterinary microbiology》2009,134(3-4):346-352
Paratuberculosis represents a major problem in farmed ruminants and at the present is considered a potential zoonosis. The disease is caused by Mycobacterium avium subsp. paratuberculosis, and susceptibility to infection is suspected to have a genetic component. Caspase recruitment domain 15 (CARD15) gene encodes for a cytosolic protein implicated in bacterial recognition during innate immunity. Crohn's disease (CD) is an idiopathic inflammatory bowel disease in humans comparable in many features to bovine paratuberculosis involving an abnormal mucosal immune response. The association between mutations in the CARD15 gene and increased risk of Crohn's disease has been described. The objective of this candidate gene case-control study was to characterize the distribution of three polymorphisms in the bovine CARD15 gene and test their association with paratuberculosis infection in cattle. Three previously reported single nucleotide polymorphisms (E2[-32] intron 1; 2197/C733R and 3020/Q1007L) were screened for the study population (431 adult cows). The statistical analysis resulted in significant differences in allelic frequencies between cases and controls for SNP2197/C733R (P<0.001), indicating a significant association between infection and variant allele. In the analysis of genotypes, a significant association was also found between SNP2197/C733R and infection status (P<0.0001); cows with the heterozygous genotype were 3.35 times more likely to be infected than cows with the reference genotype (P=0.01). Results suggest a role for CARD15 gene in the susceptibility of cattle to paratuberculosis infection. These data contribute to the understanding of paratuberculosis, suggest new similarities with Crohn's disease and provide new information for the control of bovine paratuberculosis. 相似文献
49.
50.
Bollwein H Petschow K Weber F Leiding C Stolla R 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(7-8):327-333
The aim of this study was to examine the incidence of sperm agglutinations and their relationships with sperm quality and fertility. Semen samples of 40 boars of an AI-station were investigated. Nineteen of the 40 investigated boars showed a constantly low (< 10% agglutinated sperm), 3 an intermediate (10-20%) and 6 boars a high level (> 20%) of agglutination in raw semen. The degree of agglutination in sperm samples of 12 boars varied distinctly during the investigation period. During summer more (P < 0.05) agglutinated sperm were observed (11.0 +/- 11.6%) than during winter (6.2 +/- 7.3%). There was no association between bacterial contamination and incidence of agglutinations (P > 0.05). After dilution in extender the percentage of agglutinated sperm decreased from 6.2 +/- 7.3% to 1.1 +/- 1.4% (P < 0.0001). Twenty-four hours after dilution the percentage of progressively motile sperm was 7.4% lower (P < 0.05) in ejaculates with an initially high degree of agglutination (> 20% agglutinated sperm) compared to samples with an initially low degree of agglutinated sperm (< 10%). Plasma membrane integrity, mitochondrial membrane potential, acrosome reaction and chromatin structure were independent (P > 0.05) from the level of agglutination. Fertility data did not differ (P > 0.05) between boars with low and high numbers of agglutinated sperm in raw semen. The results show that there are individual, ejaculatory and seasonal variations in the incidence and degree of agglutination. Agglutinations have a negative effect on motility of sperm and disappear to a large extent after dilution in sperm extender. They have no negative consequences on fertility. 相似文献