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排序方式: 共有218条查询结果,搜索用时 296 毫秒
21.
Objective To determine corneal sensitivity in 20 healthy adult alpacas (40 eyes) in order to establish reference values. Design Prospective study. Animals Twenty healthy, adult alpacas. Procedures Corneal sensitivity was determined by the corneal touch threshold (CTT) using a Cochet‐Bonnet esthesiometer. Five different regions of the cornea were evaluated (nasal, ventral, lateral, dorsal, and central). Results Corneal touch threshold values (in mm filament length) obtained from five corneal regions demonstrated varying corneal sensitivities. The central region (34.5 ± 7.1 mm) was the most sensitive, followed by the ventral (29.5 ± 7.2 mm), medial (29.3 ± 7.3 mm), dorsal (25.6 ± 6.3 mm), and lateral (21.8 ± 5.7 mm) regions. All pairwise comparisons of regional differences were statistically significant (P < 0.05), except for the comparison between the ventral and medial regions (P = 0.88). Evaluation of the CCT while controlling for age (2–5 years vs. 6–10 years) demonstrated an increased CTT with an increasing age for the central, ventral, medial and lateral regions. A decrease in the CTT of the dorsal region was noted with increasing age. Conclusion and Clinical Relevance Corneal touch threshold values in 40 eyes of 20 healthy adult alpacas were determined using a Cochet‐Bonnet esthesiometer. This study demonstrated the central corneal region to be most sensitive. Values obtained may serve as reference values in subsequent studies. 相似文献
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The fungal disease Fusarium head blight occurs on wheat (Triticum spp.) and barley (Hordeum vulgare L.) and is one of the worldwide problems of agriculture. It can be caused by various Fusarium species. We are characterizing the proteinases of F. culmorum to investigate how they may help the fungus to attack the grain. A trypsin-like proteinase has been purified from a gluten-containing culture medium of F. culmorum. The enzyme was maximally active at about pH 9 and 45 degrees C, but was not stable under those conditions. It was stabilized by calcium ions and by the presence of other proteins. The proteinase was most stable at pH 6-7 at ambient temperatures, but was quickly inactivated at 50 degrees C. It was strongly inhibited by p-amidino phenylmethylsulfonyl fluoride (p-APMSF), and soybean trypsin and Bowman-Birk inhibitors, and it preferentially hydrolyzed the peptide bonds of the protein substrate beta-purothionin on the C-terminal side of Arg (mainly) and Lys residues. These characteristics show that it is a trypsin-like proteinase. In addition, its N-terminal amino acid sequence was 88% identical to that of the F. oxysporum trypsin-like enzyme. The proteinase hydrolyzed the D hordein and some of the C hordeins (the barley storage proteins). This enzyme, and a subtilisin-like proteinase that we recently purified from the same organism, possibly play roles in helping the fungus to colonize grains. 相似文献
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Sofie Dobbelaere Anja Croonenborghs Amber Thys David Ptacek Yaacov Okon Jos Vanderleyden 《Biology and Fertility of Soils》2002,36(4):284-297
Under the controlled conditions of the greenhouse and by varying some biotic and abiotic factors, we tried to identify some of the factors critical to obtain successful Azospirillum inoculation. Spring wheat and grain maize were inoculated with different concentrations of the wild type strains A. brasilense Sp245 and A. irakense KBC1, and grown in a substrate with varying concentrations of organic matter (OM) and N fertiliser. The inoculum concentration was one of the factors that influenced most the outcome of an inoculation experiment on wheat, with lower inoculum concentrations (105-106 cfu plant-1) stimulating root development and plant dry weight and higher inoculum concentrations (107-108 cfu plant-1) having no effect or sometimes even inhibiting root development. The effect of inoculation was most pronounced at low to intermediate N fertilisation levels, while the OM content of the substrate had no effect. Inoculation was found to affect early plant and root development, plant and root dry weight, grain yield and the N-uptake efficiency of plants. However, inoculation did not change the N concentration in plants or grains. In addition, a difference in the ability of both strains to stimulate plant growth and N uptake of wheat and maize was observed, with A. brasilense Sp245 having most effect on spring wheat and A. irakense KBC1 being more effective on grain maize. The significance of the obtained results for agriculture is discussed. 相似文献
24.
Boesen HT Jensen TK Schmidt AS Jensen BB Jensen SM Møller K 《Veterinary microbiology》2004,103(1-2):35-45
The objective of this investigation was to study if different feeding strategies influence experimental infections of pigs with Lawsonia intracellularis, the causative agent of proliferative enteropathy. In three sequential trials, a total of 144 weaned pigs were fed five different diets all made from a standard diet based on wheat and barley as carbohydrate source and soybean as protein source. The five diets were: a standard diet (fine ground and pelleted), the standard diet fed as fermented liquid feed, the standard diet added 1.8% formic acid, the standard diet added 2.4% lactic acid and a diet similar to the standard diet (made from the same ingredients), but fed coarse ground. Twenty-four pigs on each diet were orally inoculated with L. intracellularis and growth performance and faecal excretion of bacteria were monitored. Twenty-four pigs fed the standard diet were included as not experimentally infected controls. Pigs in the first two trials were sacrificed 4 weeks post-inoculation, whereas animals in the third trial were sacrificed after 5 weeks. Pigs in all experimentally infected groups excreted L. intracellularis. The fermented liquid diet delayed the excretion of L. intracellularis and furthermore, pigs fed the standard diet supplemented with lactic acid had limited pathological lesions when the intestines were examined 4 weeks after inoculation. The growth performance was reduced in pigs experimentally challenged with L. intracellularis, however the prevalence and severity of diarrhea was limited. 相似文献
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Hartmann AD Wilhelm N Balzarini J Hartmann K 《Journal of Feline Medicine and Surgery》2012,14(2):107-112
In in vitro studies, the acyclic nucleoside phosphonate 9-(2-phosphonylmethoxypropyl)-2,6-diaminopurine (PMPDAP) inhibited the replication of feline immunodeficiency virus (FIV). No information about its clinical efficacy is available so far. The aim of this prospective placebo-controlled, double-blinded study was to evaluate the antiviral efficacy of PMPDAP in cats naturally infected with FIV. Twenty cats were randomly assigned to two treatment groups receiving either PMPDAP (25 mg/kg) or placebo twice per week subcutaneously for 6 weeks. The general health status (Karnofsky's score), clinical signs, laboratory, immunological, and surrogate parameters were evaluated. No significant differences were found between PMPDAP- and placebo-treated cats, although cats treated with PMPDAP showed a tendency for improvement in their Karnofsky's score and clinical signs. Haematological side effects were noted in the PMPDAP-treated cats. Thus, PMPDAP may be an option in treating cats if it becomes available for veterinarians, but side effects have been monitored. 相似文献
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Jores J Nkando I Sterner-Kock A Haider W Poole J Unger H Muriuki C Wesonga H Taracha EL 《Veterinary immunology and immunopathology》2008,124(1-2):192-197
Contagious bovine pleuropneumonia (CBPP) is a lung disease caused by the bacterial pathogen Mycoplasma mycoides ssp. mycoides small colony type (MmmSC). It has been spreading due to a number of factors including poor vaccine efficacy and poor sensitivity of current diagnostic tests. The purpose of this study was to assess interferon gamma (IFN-gamma) release after stimulation of peripheral blood mononuclear cells (PBMC) from experimentally infected cattle. PBMC collected from 15 artificially infected animals were incubated with different concentrations of total MmmSC antigen. After 72h of incubation the IFN-gamma release was measured and found to be elevated in 11 animals. We did not observe a correlation between IFN-gamma release of animals with and without pathomorphological gross lesions. Therefore, our data do not confirm a role for CD4 T-lymphocytes in protection, since there is no correlation between IFN-g secretion (supposed to be mainly derived from CD4 T-cells) and disease severity. Additionally, we applied immunocytochemistry on affected lung tissue and detected no build up of T-lymphocytes (CD4 T-cells, CD8 T-cells) but a high presence of myeloid cells. 相似文献