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41.
Eskild-Jensen A Rehling M Nielsen AS Nielsen LE Frøkiaer J 《American journal of veterinary research》2002,63(8):1203-1206
OBJECTIVE: To compare renal clearance of technetium Tc 99m pentetate with plasma clearance by use of a glomerular filtration rate technique in pigs from 3 to 24 weeks of age. Animals: 24 female pigs. Procedure: At the time of investigation, 5 pigs were 3 weeks old, 6 pigs were 6 weeks old, 8 pigs were 12 weeks old, and 5 pigs were 24 weeks old. Plasma clearance of technetium Tc 99m pentetate was measured by the use of a single injection technique followed by collection of multiple blood samples until 5 hours after the injection. Simultaneously, urine was collected through a urinary catheter, and the renal clearance of technetiumTc 99m pentetate was calculated. Plasma clearance of technetium Tc 99m pentetate was correlated with the renal clearance (r = 0.95). Plasma clearance was higher than renal clearance at all ages (mean, 5.8%), indicating extrarenal clearance of technetium Tc 99m pentetate or methodologic errors. Volume of distribution increased with increasing age but decreased as a fraction of body weight. CONCLUSIONS: Plasma clearance of technetium Tc 99m pentetate estimates renal clearance with acceptable precision when using single injection technique and multiple biood samples in pigs from 3 to 24 weeks of age. 相似文献
42.
Oleksiewicz MB Kristensen B Ladekjaer-Mikkelsen AS Nielsen J 《Veterinary immunology and immunopathology》2002,86(1-2):55-77
The extracellular domains of swine leukocyte antigen class I (SLA-I, major histocompatibility complex protein class I) were cloned and sequenced for two haplotypes (H4 and H7) which do not share any alleles based on serological typing, and which are the most important in Danish farmed pigs. The extracellular domain of SLA-I was connected to porcine beta2 microglobulin by glycine-rich linkers. The engineered single-chain proteins, consisting of fused SLA-I and beta2 microglobulin, were overexpressed as inclusion bodies in Escherichia coli. Also, variants were made of the single-chain proteins, by linking them through glycine-rich linkers to peptides representing T-cell epitopes from classical swine fever virus (CSFV) and foot-and-mouth disease virus (FMDV). An in vitro refold assay was developed, using a monoclonal anti-SLA antibody (PT85A) to gauge refolding. The single best-defined, SLA-I restricted porcine CD8(+) T-cell epitope currently known is a 9-residue peptide from the polyprotein of CSFV (J. Gen. Virol. 76 (1995) 3039). Based on results with the CSFV epitope and two porcine haplotypes (H4 and H7), the in vitro refold assay appeared able to discriminate between peptide-free and peptide-occupied forms of SLA-I. It remains to be seen whether the rapid and technically very simple in vitro refold assay described here will prove generally applicable for the screening of virus-derived peptides for SLA-I binding. 相似文献
43.
The accuracy of three diagnostic tests for paratuberculosis was evaluated using maximum-likelihood estimation of sensitivity and specificity. We also explored the variety of estimates that can be obtained if the tests are to be used in populations of different composition with regard to infection and disease states. Two enzyme-linked immunosorbent assays (ELISAs) were evaluated separately with the faecal culture (FC). The study was carried out as a cross-sectional field study to cover all likely states of infection with Mycobacterium avium subsp. paratuberculosis.The three basic assumptions for the maximum-likelihood technique were evaluated to validate the results. Our accuracy estimates for the ELISAs were not very different from those previously published, but those for faecal culture differed if a different cut-off value was chosen for the ELISA. If faecal culture was used for screening in a Danish dairy region where the median ELISA reading was a measure of the general disease situation, the sensitivity of the faecal culture was 20-25%. If faecal culture was used as a confirmatory test on cows with a high ELISA reading (and thus high level of antibodies), the sensitivity of the faecal culture would be in the range 60-70%. These results emphasise the importance of the composition of a target population before selecting a specific diagnostic test for a given purpose. We concluded that faecal culture is useful for confirmation but not for screening purposes. 相似文献
44.
Andreasen M Baekbo P Nielsen JP 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(3):161-171
The objective of this experimental study was to determine the effects of aerial ammonia on disease development and bacterial colonization in weaned pigs inoculated with toxigenic Pasteurella multocida and Mycoplasma hyopneumoniae. Two groups of 10 pigs each were continuously exposed to 50 and 100 p.p.m. ammonia, respectively, and compared to a non-exposed control group of 20 pigs. Following aerosol inoculation with M. hyopneumoniae at day 9, all pigs were aerosol-inoculated with toxigenic P. multocida type A at days 28, 42 and 56. At day 63 they were euthanized. Clinical signs including coughing and respiratory distress were present in all groups following inoculation. No significant differences could be established in the extent or frequency of pneumonia between ammonia-exposed pigs and controls, or in the extent of conchal atrophy, the frequency of isolation of toxigenic P. multocida from conchae, tonsils, lungs and kidneys, or the average daily weight gain. The recovery of toxigenic P. multocida from nasal swabs following inoculation was significantly greater in pigs exposed to 50 p.p.m. ammonia or more as compared to the control group. In conclusion, high levels of ammonia combined with inoculations with M. hyopneumoniae and toxigenic P. multocida had no significant effect on disease development, but may have enhanced colonization by toxigenic P. multocida on the nasal turbinates. 相似文献
45.
C.I. O''Connor-Robison MS B.D. Nielsen MS PhD R. Morris BS 《Journal of Equine Veterinary Science》2007,27(12):535-538
Six mature Arabian geldings were used in a two-period crossover study to investigate the effects of cellulase supplementation on fiber digestion. Horses were randomly assigned to either a control (CO; n = 3) or a cellulase (CE; n = 3) treatment for the first period and then treatments were switched for period 2. Each period consisted of a 10-day diet adaptation followed by a 3-day total fecal collection. The enzyme mixture contained 40,000 cellulase units/g and was fed at a rate of 3 g/day split evenly between two feedings. During the diet adaptation period, horses had ad libitum access to timothy hay and were also fed 165 g whole oats as a carrier for the supplement. When eating the CO treatment, horses consumed 16% more hay than when on the CE treatment (P = .004). Fecal output also tended to be greater when horses consumed the CO treatment as compared with CE treatment (P = .07). No differences were found between treatments for fecal percent dry matter (DM%), fecal neutral detergent fiber (NDF), fecal acid detergent fiber (ADF), fecal nitrogen (N), or fecal gross energy (GE). There was a trend for horses consuming the CO treatment to digest more NDF than when consuming the CE treatment (34.6% ± 1.5 vs 31% ± 1.5; P = .07). Horses also digested a greater %ADF, %N, and Mcal of energy when consuming the CO treatment than when consuming the CE treatment (P < .05). Cellulase addition to a hay-based horse diet decreased digestion of fiber components. 相似文献
46.
F. A. Zuckermann M. D. Pescovitz B. Aasted J. Dominguez I. Trebichavsky B. Novikov I. Valpotic J. Nielsen S. Arn D. H. Sachs J. K. Lunney P. Boyd J. Walker R. Lee W. C. Davis I. R. Barbosa A. Saalmü ller 《Veterinary immunology and immunopathology》1998,60(3-4):291-303
Based on an analysis of their reactivity with porcine peripheral blood lymphocytes (PBL), only three of the 57 mAbs assigned to the T cell/activation marker group were grouped into cluster T9 along with the two wCD8 workshop standard mAbs 76-2-11 (CD8a) and 11/295/33 (CD8b). Their placement was verified through the use of two-color cytofluorometry which established that all three mAbs (STH101, #090; UCP1H12-2, #139; and PG164A, #051) bind exclusively to CD8+ cells. Moreover, like the CD8 standard mAbs, these three mAbs reacted with two proteins with a MW of 33 and 35 kDa from lymphocyte lysates and were, thus, given the wCD8 designation. Because the mAb STH101 inhibited the binding of mAb 76-2-11 but not of 11/295/33, it was given the wCD8a designation. The reactivity of the other two new mAbs in the T9 cluster with the various subsets of CD8+ lymphocytes were distinct from that of the other members in this cluster including the standards. Although the characteristic porcine CD8 staining pattern consisting of CD8low and CD8high cells was obtained with the mAb UCP1H12-2, a wider gap between the fluorescence intensity of the CD8low and CD8high lymphocytes was observed. In contrast, the mAb PG164A, not only exclusively reacted with CD4−/CD8high lymphocytes, but it also failed to recognize CD4/CD8 double positive lymphocytes. It was concluded that this mAb is specific for a previously unrecognized CD8 epitope, and was, thus, given the wCD8c designation. A very similar reactivity pattern to that of PG164A was observed for two other mAbs (STH106, #094; and SwNL554.1, #009). Although these two mAbs were not originally positioned in the T cell subgroup because of their reactivity and their ability to inhibit the binding of PG164A, they were given the wCD8c designation. Overall, five new wCD8 mAbs were identified. Although the molecular basis for the differences in PBL recognition by these mAbs is not yet understood, they will be important in defining the role of CD8+ lymphocyte subsets in health and disease. 相似文献
47.
J E Blake N O Nielsen W P Heuschele 《Journal of the American Veterinary Medical Association》1990,196(7):1141-1143
The severity of lymphoproliferative disease associated with malignant catarrhal fever was extremely variable among 25 animals at the San Diego Wild Animal Park. Severe lymphoproliferative disease was seen in 3 of 10 Formosan Sika deer (Cervus nippon taiouanus), 3 of 6 Indian Axis deer (Cervus a axis), 3 of 6 Barasingha deer (Cervus d duvauceli), and 1 of 3 Nilgai (Boselaphus tragocamelus). Two Sika deer and 2 Barasingha deer had lesions morphologically indistinguishable from lymphosarcoma. Our findings were consistent with the hypothesis that alcelaphine herpesvirus-1 has oncogenic potential. 相似文献
48.
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50.
A "dipstick" enzyme immunoassay for detection of antibody to Brucella abortus in cattle sera. 下载免费PDF全文
K Nielsen R Ballinger J Stiller B Rosenbaum 《Canadian journal of veterinary research》1985,49(3):298-302
An enzyme immunoassay that utilizes antigen bound to a matrix which can be removed from the substrate to stop development is described. The assay which is performed in glass or plastic disposable tubes uses Gel-Bond film strips for attachment of antigen. The only equipment requirements are a rotary shaker and a spectrophotometer (optional). The antigen coated strips are passed through a series of tubes containing test serum, wash solution, antibody-enzyme conjugate, wash solution and substrate-chromogen taking about 45 minutes to perform. In testing sera with or without antibody to Brucella abortus a very high correlation existed between same day tests and tests performed over several days as well as with data on the same sera obtained by an enzyme immunoassay in a microtiter format. 相似文献