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191.
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Expression of β2-integrin on monocytes and blood polymorphonuclear leukocytes in the periparturient period in dairy cows 下载免费PDF全文
Araceli Diez-Fraile Luc Duchateau Evelyne Meyer Christian Burvenich 《Canadian journal of veterinary research》2003,67(3):235-238
The hypothesis that an altered expression of CD11/CD18 on bovine circulating monocytes, polymorphonuclear leukocytes (PMN), or both, contributes to an increased mastitis susceptibility in periparturient cows was tested. Expression of CD18 and CD11a, -b, -c on bovine monocytes and PMN were assessed in 8 Friesian-Holstein cows by flow cytometry from 2 wk before calving to 5 wk after calving. Minor changes in adhesion molecule expression levels were detected throughout the experimental period. Compared with PMN, monocytes exhibited an expression level that was similar for CD18, higher for CD11a and CD11c, but lower for CD11b. Differences in density may reflect the relative importance of these adhesion molecules on both leukocyte types. In this study, the decreased number of milk resident macrophages and PMN observed during the periparturient period could not be attributed to changes of CD11/CD18 levels on circulating leukocytes. 相似文献
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Cadmium (Cd) sorption isotherms were estimated by two different analytical approaches to assess the influence of initial Cd concentrations of soil matrix on the sorption of added Cd. For the laboratory experiments a heterogeneous set of samples was collected to include a wide range of different initial Cd concentrations. Comparison of both analytical methods (conventional analysis, radioanalysis) resulted in a strong conformity of Cd contents in solution at equilibrium. The calculated Cd concentrations in the soil solid phase differ according to the analytical approach for considering the initial contents. The determination of the initial contents by the proposed radioanalytical method with 109Cd resulted in long linear Freundlich‐isotherms, even in the low concentration range. Thus, radioanalysis seems to be the most suitable method to recognise the initial contents of Cd in soil. EDTA extractable Cd represent the initial concentrations, which are averaged over solid and liquid phase. However, depending on the sorption characteristics of the soil these rates vary. In the investigated set of soil samples 52.3 to 99.3% of Cd must be added to the solid phase. 相似文献
195.
Dynamic oxygen mapping in the root zone by fluorescence dye imaging combined with neutron radiography 总被引:1,自引:0,他引:1
Nicole Rudolph Hanna G. Esser Andrea Carminati Ahmad B. Moradi André Hilger Nikolay Kardjilov Stefan Nagl Sascha E. Oswald 《Journal of Soils and Sediments》2012,12(1):63-74
Purpose
The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it. 相似文献196.
The reliability and reproducibility of random amplified polymorphic DNA analysis (RAPD) was compared with restriction fragment length polymorphism (RFLP) by analysing three virus strains isolated from zoo animals in Berlin and three isolates which were cultivated from pets from Northern Germany. The RAPD technique was evaluated as a reliable tool with good reproducibility of the patterns for each virus strain investigated. Problems of interpretation due to inconsistent intensity of bands in different polymerase chain reaction runs may arise for less experienced personnel. The RAPD analysis can be performed within one working day and needs less DNA compared with RFLP so costs will be reduced. The obvious advantage of RFLP is that the pattern can be traced to the recognition site of the restriction enzyme whereas the RAPD primer sequence is not present in the orthopoxvirus genome at all. To the authors knowledge, the RAPD technique has never been applied in DNA viruses before and they conclude that this technique is a useful tool for the discrimination of closely related cowpoxviruses. 相似文献
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Adrenocortical suppression associated with topical otic administration of glucocorticoids in dogs 总被引:2,自引:0,他引:2
K A Moriello S L Fehrer-Sawyer D J Meyer B Feder 《Journal of the American Veterinary Medical Association》1988,193(3):329-331
Commercial otic preparations that contained dexamethasone or triamcinolone acetate were applied twice daily to both ears of 2 groups of dogs (n = 8). Marked adrenocortical suppression, reflected by low serum cortisol concentrations, was observed in all dogs. Results of ACTH response tests were blunted after 7 days of treatment. Twenty-one days after treatment, serum cortisol concentrations still were suppressed in all dogs, compared with pretreatment control concentrations. Fourteen days after cessation of otic treatment, 5 of 8 dogs still had inadequate release of cortisol in response to ACTH. 相似文献
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