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321.
The effect of Escherichia coli lipopolysaccharide (LPS) on the expression of major histocompatibility complex (MHC) class II molecules by bovine mammary macrophages was examined. The ability of LPS-treated mammary macrophages to support antigen-specific T-cell proliferation, as a measure of their antigen presentation ability, was also evaluated. For this purpose, control and LPS-treated macrophages were pulsed with heat-killed Staphylococcus aureus and then cultured with S. aureus-sensitized T-cells. Our data show that LPS had no significant effect on the expression of MHC class II molecules on the surface of mammary macrophages. Furthermore, LPS-induced macrophages were no more active in supporting T-cell proliferation on a per cell basis than unstimulated macrophages. The lack of macrophage response to LPS with respect to expression of MHC class II molecules and the antigen presentation ability is another example of the hyporesponsive nature of macrophages isolated from the bovine mammary gland. 相似文献
322.
A case of hypertrophic osteopathy secondary to a pulmonary spindle cell sarcoma is described. The 9‐year‐old male cat presented with a 1‐month history of decreased appetite, decreased activity and progressive lameness with swelling and pain of all four limbs. Thoracic radiographs showed a soft tissue opaque mass in the left caudal lung lobe. Radiographs of all limbs showed extensive periosteal new bone formation of uniform opacity demonstrating a ‘palisading’ pattern. The lung mass was removed at exploratory thoracotomy; histopathological examination diagnosed a low‐grade spindle cell sarcoma. Prior to surgery, the cat had a non‐specific conjunctivitis that resolved spontaneously following lobectomy raising the possibility of a paraneoplastic association. The lameness also resolved; six months after surgery, the periosteal palisading of new bone on the long bones had remodelled, and there was no evidence of pulmonary metastases. 相似文献
323.
The development of a simple fecal immunoreactive progestin assay to monitor reproductive function in swine. 
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下载免费PDF全文 H Sanders R Rajamahendran B Burton 《The Canadian veterinary journal. La revue veterinaire canadienne》1994,35(6):355-358
The objectives of the study were to (a) develop a simple fecal progestin extraction and radioimmunoassay method to measure immunoreactive progestin in porcine feces and (b) to characterize fecal progestin profiles during the estrous cycle and postpartum. A simple extraction method was developed in trial 1 and the mean (+/- SD) progestin recovery of the method was 84.3 +/- 3.5%. Progesterone levels measured at five different spiked concentrations (50, 100, 200, 400, and 500 ng/0.5 g feces) showed no systematic error. The sensitivity of the assay was 0.16 nmol/L of the extract. Trial 2 involved collecting fecal samples from six cycling sows every second or third day, beginning on the day of estrus (day 0) and continuing until day 22. The mean (+/- SD) fecal progestin concentrations of these sows determined by the above assay during days 0-5, days 6-10, days 11-15, and days 16-21 were 87.1 +/- 17.5, 262.6 +/- 102.1, 1188.2 +/- 454.1, and 897.3 +/- 274.1 x 10(-3) nmol/g feces, respectively. In trial 3, fecal samples from six postpartum sows were collected at weekly intervals beginning from day 7 after farrowing until day 50. The mean (+/- SD) fecal progestin concentrations were 111.0 +/- 61.1, 74.1 +/- 21.3, 66.5 +/- 26.1, 122.7 +/- 58.8 and 533.5 +/- 244.2 x 10(-3) nmol/g feces, during days 7-10, days 11-20, days 21-30, days 31-40, and days 41-50 postpartum, respectively. The results indicate that simple fecal progestin extraction and assay are feasible alternatives to the standard blood progesterone assays for monitoring reproductive function in swine. 相似文献
324.
325.
Patient characteristics,prognostic factors and outcome of dogs with high‐grade primary mediastinal lymphoma 下载免费PDF全文
下载免费PDF全文 E. L. Moore W. Vernau R. B. Rebhun K. A. Skorupski J. H. Burton 《Veterinary and comparative oncology》2018,16(1):E45-E51
The goals of this retrospective study were to determine the patient characteristics of dogs with high‐grade primary mediastinal lymphoma and to determine outcome and associated prognostic factors. A total of 42 dogs were identified, in which 36 received treatment and had follow‐up information available. The most common clinical signs included lethargy, anorexia and polyuria/polydipsia. Hypercalcemia and pleural effusion were common findings at diagnosis. The phenotype was almost exclusively T‐cell, most often in association with lymphoblastic cytomorphology as defined by the World Health Organization (WHO) lymphoma classification scheme. The overall progression‐free survival (PFS) and overall survival (OS) were 133 and 183 days, respectively. Treatment with a CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) protocol was associated with an improved PFS (144 days) and OS (194 days) when compared with dogs that received other medical therapies (P = .005 and P = .002, respectively); the absence of pleural effusion at diagnosis was associated with an increased OS but not PFS. These results suggest that while the prognosis for dogs with mediastinal lymphoma is poor, survival may be improved with treatment using a CHOP‐based protocol. 相似文献
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327.
The Effect of Urine Concentration and pH on the Growth of Escherichia Coli in Canine Urine In Vitro 下载免费PDF全文
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Context
Fires and insect outbreaks are important agents of forest landscape change, but the classification and distribution of these combined processes remain unstudied aspects of forest disturbance regimes.Objectives
We sought to map areas of land characterized by homogenous fire regime (HFR) attributes and by distinctive combinations of fire, bark beetles and defoliating insect outbreaks, and how their distribution might change should current climatic trends continue.Methods
We used a 41-year history of mapped fires and forest insect outbreaks to classify HFRs and combined fire and insect disturbance regimes (HDRs). Spatially constrained cluster analysis of 2524 20-km grid cells used mean annual area burned, ignition Julian date, fire size and fire frequency to delineate HFR zones. Mean annual areas burned, affected by bark beetles, and affected by defoliators were used to delineate HDR zones. Random forests classification used climate associations of HDRs to project likely changes in their distribution.Results
Eighteen HFR zones accounted for 30% of variance, compared to 27 HDR zones accounting for 59% of variance. Fire regime designation had low predictive power in explaining 23 homogenous insect outbreak regimes or the 27 HDRs. Climate change projections indicate a northward migration of current HDR zones. Conditions suitable for defoliator outbreaks are projected to increase, resulting in a projected increase in the total rate of forest disturbance.Conclusions
When describing forest disturbance regimes, it is important to consider the combined and possibly interacting agents of tree mortality, which can result in emergent properties not predictable from any single agent.329.
330.
Frequency and Severity of Neutropenia Associated with Food and Drug Administration Approved and Compounded Formulations of Lomustine in Dogs with Cancer 下载免费PDF全文
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