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991.
992.
Haptoglobin (HP) is a common minor to moderate acute-phase protein in mammals. It has been described as increasing under a variety of conditions in horses, with the use of different assay methods. The goal of the current study was to provide updated information regarding this biomarker by using a commonly available automated assay. In the present study, reference intervals for HP were generated using 43 serum samples from clinically normal horses. The reference interval was determined via the robust method as 0.29-2.26 mg/ml. A statistically significant 3.3-fold mean increase was observed in HP levels from a clinically abnormal group of horses (n = 33). A weak but significant correlation was found between total white blood cell count and HP levels (r = 0.37, P < .05). A significantly higher level of HP expression was observed in samples acquired from patients whose clinical signs lasted for 7 days or longer than from those whose signs were 4 days or less. 相似文献
993.
994.
A technique was developed for the measurement of levels of caesium radionuclides (137Cs+134Cs) in live reindeer, cattle, and sheep and in carcasses from these species. The instrument used was a sodium iodide scintillation detector coupled to a portable multi-channel analyser.Based on a combination of background measurements and measurements of impulses from animals with the detector in different anatomical positions we recommmend the following procedures: Lamb: The detector placed on os sacrum (standing animal). Reindeer: The detector placed between the hind legs (animal lying on its side). Cattle: The detector placed on the back of the standing animal, midway between os sacrum and trochanter major.Average geometrical factors for live animals were estimated. It was a linear correlation between measured activity levels in meat samples and counted impulses per sec in live animals. Geometrical factors were estimated at 95% confidence level with uncertainty between 6–14%. The detection limits varied between 50–200 Bq (becquerel)/kg in areas with ground depositions between 5–200 kBq/m2. Since the winter 1986/87 the technique has been the standard procedure for monitoring slaughter animals and carcasses for radiocaesium activity concentrations. 相似文献
995.
A rostrocaudal (RCd) nasal view was developed in large breed mesaticephalic dogs using a complete, subsequently sectioned, skull and cadaver specimens to optimise the radiographic technique and evaluate normal anatomic features. Gelatin was placed in one nasal passage of the cadaver specimens to mimic the effects of nasal pathology. The latter specimens and 18 clinical cases with suspected nasal disease were evaluated to determine the usefulness of the RCd view compared to standard nasal views. An optimal RCd view was obtained with the dog in dorsal recumbency and the head symmetrically positioned with the hard palate perpendicular to the table using a table top technique with 8:1 grid, collimating to the nasal region and centring the primary beam on the philtrum. The dorsolateral aspects of the maxillary bone, the nasal bones, septal sulcus of the vomer, mucosa lined nasal septum and conchae could be seen. A centrodorsal more radiolucent area representing the ethmoid bone region was also visible. Gelatin soft tissue opacification of the nasal passage could be seen more clearly in RCd nasal view than in occlusal dorsoventral view. In clinical cases the RCd view was useful to build up a 3-dimensional image of nasal passage pathology as well as to detect nasal septum and osseous nasal border pathology not visible in other views. This view is particularly useful in cases where cross-sectional imaging modalities are not available or where the nasal investigation is limited by cost considerations. 相似文献
996.
Experimental model of swine pneumonic pasteurellosis using crude Actinobacillus pleuropneumoniae cytotoxin and Pasteurella multocida given endobronchially. 下载免费PDF全文
This study was designed to develop and characterize a swine pneumonic pasteurellosis model by concurrent introduction of Pasteurella multocida type A and Actinobacillus pleuropneumoniae crude cytotoxin. After a series of preliminary experiments, a combination of 4 x 10(9) P. multocida and 4,000 toxic units of A. pleuropneumoniae crude cytotoxin was determined to produce optimal results. A total of 48 pigs were divided into four groups of 12 pigs each. The control group received buffered saline only. Four pigs from each group were randomly selected for necropsy 3, 7 and 14 days postinoculation (PI). Inoculation of pigs with P. multocida and A. pleuropneumoniae cytotoxin (group 1) resulted in moderate to severe pneumonia. Pasteurella multocida was isolated from pneumonic lesions, grossly normal lung, and bronchial lymph nodes of all group 1 pigs throughout the 14 day experimental period. Pathological changes typical of field cases of swine pneumonic pasteurellosis were produced. Pigs inoculated with P. multocida alone (group 2) had pneumonic lesions and P. multocida was reisolated from lungs at three days PI. Pasteurella multocida was not isolated from these pigs at 7 and 14 days PI, except for one pig in which an abscess developed in the thorax. Pulmonary lesions induced by A. pleuropneumoniae crude cytotoxin alone (group 3) were transient and resolved by seven days PI. Group 1 pigs had significantly greater lung lesion volumes than group 2 and 3 pigs at 3, 7 and 14 days PI. Statistical analysis indicated a significant interactive effect of P. multocida and A. pleuropneumoniae cytotoxin on the development of lung lesion volumes at 7 and 14 days PI (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
G. B. L. Harrison T. R. Shakes C. M. Robinson S. B. Lawrence D. D. Heath R. P. Dempster M. W. Lightowlers M. D. Rickard 《Veterinary immunology and immunopathology》1999,70(3-4):161-172
The efficacy and safety of a recombinant Taenia ovis protein was tested in sheep using 13 different adjuvant formulations, including oil adjuvants, aluminium salts, saponin, Iscoms and DEAE-dextran. The oil adjuvants, saponin and DEAE-dextran gave the highest antibody responses and greatest degree of protection against challenge infection with T. ovis eggs. Duration of immunity studies with a saponin based vaccine showed that highly significant protection (>90% reduction of cyst numbers) was achieved when sheep were challenge infected one month after immunisation. Significant protection (79%) was still present when sheep were challenged 6 months after immunisation. The optimum dose for this batch of saponin was 10 mg, which stimulated a peak antibody titre of 38,400, 4 weeks after immunisation and did not cause injection site reactions. Dialysed saponin was shown to retain its adjuvant properties and allowed an increase in dose to 30 mg without site reaction, resulting in a peak antibody titre of 51,200. 相似文献
998.
999.
Van de Weerdt ML Coghe J Uystepruyst C Deby-Dupont G Lekeux P 《Veterinary journal (London, England : 1997)》1999,157(1):39-49
The purposes of this study were: (1) to investigate which arachidonic acid metabolites contributed to platelet-activating factor (PAF) induced pulmonary dysfunction; and (2) to compare the effect of two non-steroidal anti-inflammatory drugs, phenylbutazone and ketoprofen in a model of PAF-induced reversible lung inflammation in six calves. In placebo and phenylbutazone groups, PAF infusion induced significant dysfunctions in the pattern of breathing, mechanics of breathing and gas exchange. These dysfunctions were prevented by ketoprofen pretreatment, except for the mechanics of breathing which was moderately but significantly altered by the PAF challenge. In all calves, leukotriene (LT) B4 plasma concentrations did not significantly increase above baseline values at any time. Prostaglandin (PG) E2 plasma concentrations showed a minor significant increase in phenylbutazone pretreated calves (55.8 +/- 25.8 pg/mL from 36.7 +/- 16.13 pg/mL). Thromboxane (TX) B2 plasma concentration was significantly increased during PAF challenge in placebo- and phenylbutazone-pretreated groups, but not in ketoprofen-pretreated calves (1580.0 +/- 1370 from 42.7 +/- 10.7 pg/mL; 2340 +/- 477 from 63 +/- 32 pg/mL; and 36.5 +/- 4.12 from 39.3 +/- 12.0 pg/mL, respectively). These data suggest that TXA2 is an important cyclooxygenase metabolite of arachidonic acid produced in response to PAF and that ketoprofen (intramuscular injection, 3 mg/kg) is more effective than phenylbutazone (intramuscular injection, 10 mg/kg) in preventing respiratory dysfunctions induced by the PAF challenge 30 min after drug administration. Ketoprofen did not suppress totally the PAF-induced changes in mechanics of breathing, which suggests that PAF or a secondary release of mediators could have a direct action on airway smooth muscle. 相似文献
1000.
This study was aimed at testing the hypothesis that insulin-like growth factor binding protein (IGFBP)-3 can modulate hormone-dependent differentiation of granulosa cells in vitro. Granulosa cells from small (1 to 5 mm) follicles were collected from cattle, cultured for 2 d in medium containing 10% fetal calf serum, washed, and then treated for an additional 2 d in serum-free medium with follicle-stimulating hormone (FSH) (50 ng/ml), recombinant human IGF-I (0, 1.3, 4.0, or 13.3 nM), or recombinant human IGFBP-3 (0 to 4.26 nM). In one series of experiments, IGFBP-3 (0.53 and 2.13 nM) inhibited (51% to 92% decreases; P < 0.05) progesterone and estradiol production induced by 1.3 nM of IGF-I, but did not influence (P > 0.10) granulosa cell numbers or steroidogenesis in the absence of IGF-I. Only 4.26 nM of IGFBP-3 inhibited (by 35%) the increase in granulosa cell numbers induced by 1.3 nM of IGF-I. In another series of experiments, 13.3 nM of IGF-I, but not 4.0 nM of IGF-I, was able to completely overcome the inhibitory effect of 4.26 nM of IGFBP-3 on estradiol production. The increase in cell numbers induced by 4.0 and 13.3 nM of IGF-I was attenuated (P < 0.001) by 4.26 nM of IGFBP-3. In a third series of experiments, IGFBP-3 inhibited 125I-IGF-I binding to granulosa cells. These results indicate that IGFBP-3 has a pronounced inhibitory effect on IGF-I action in cultured bovine granulosa cells, and that this inhibitory effect is likely attributable to IGFBP-3 binding/sequestering IGF-I. Thus, IGFBP-3 may play a significant role in regulating granulosa cell proliferation and steroidogenesis during follicular development in cattle. 相似文献