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排序方式: 共有490条查询结果,搜索用时 156 毫秒
1.
Petterino C Bedin M Podestá G Ratto A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):95-100
A 6-year-old intact female corn snake (Elaphe guttata guttata) was presented with a 3-week history of anorexia. Coelomic radiographs revealed a 9 x 4 cm soft tissue opacity suggestive of a right ovarian enlargement. The mass (9 x 5 x 4 cm) was surgically removed, and multiple smears from tissue sections were stained with Diff-Quik. Multiple tissue samples from the mass were collected and fixed in formalin. Cytologic specimens were moderately cellular and contained light pink amorphous background material. The cells were primarily spindle-shaped with moderate to marked anisocytosis and anisokaryosis. Cells sometimes were round to polygonal, and rarely were arranged in small clusters. Macrophages occasionally were observed. Histologic specimens consisted of a highly cellular mass composed of pleomorphic, spindle-shaped cells and, occasionally, round to polygonal cells arranged in irregular fascicles. The neoplastic cells were immunoreactive for cytokeratin (AE1/AE3), smooth muscle actin, and skeletal muscle actin, but did not stain for vimentin or desmin. On the basis of the morphologic and immunohistochemical results, a diagnosis of ovarian undifferentiated carcinoma was made. In this report, we describe the challenges of using immunohistochemistry to diagnose this uncommon type of tumor in reptiles. 相似文献
2.
Riondato F D'Angelo A Miniscalco B Bellino C Guglielmino R 《Veterinary journal (London, England : 1997)》2008,175(3):364-368
The effect of transportation on peripheral blood lymphocyte subsets in 24 calves was investigated by flow cytometry. Blood was collected before departure, on arrival, at 24h and 1 week after arrival. Highest leucocyte and neutrophil counts, associated with increased concentrations of cortisol and catecholamines, indicated that stress was maximal upon arrival. At this time, a decrease in the percentages of all T lymphocyte subsets was evident, while they did not decrease as absolute counts. The proportion of CD21(+) cells did not change, indicating that the relative reduction of T lymphocyte subsets was not related to an increase in B lymphocytes. These variations may be due to the increase of a natural killer (NK) cell subset. NK cell expansion, together with increasing lymphocyte count and increasing major histocompatibility complex class II expression, may indicate stress-induced stimulation of the immune system. 相似文献
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4.
Cristel álvarez-Castillo Ian MacGregor-Fors Stefan L.Arriaga-Weiss Claudio Mota-Vargas Diego Santiago-Alarcon 《中国鸟类》2022,(1):36-42
Urban ecosystems are evolutionarily recent novel environments acting as biodiversity filters.Psittacidae birds are considered successful urban adapters mainly d... 相似文献
5.
Merit Meier Regula Bettschart-Wolfensberger Colin Claudio Schwarzwald Karine Portier Annette Gysler Simone Katja Ringer 《Journal of veterinary pharmacology and therapeutics》2020,43(5):470-476
Dobutamine is routinely used to improve cardiovascular function in anaesthetized horses. However, dobutamine in conscious horses is insufficiently investigated. Ten research horses that were already instrumented for a preceding trial were included into the study. Cardiovascular variables were recorded and blood samples taken after instrumentation (Baseline), before starting dobutamine and after 10 min of dobutamine infusion (2 µg kg−1 min−1). A significant increase in systemic blood pressure, mean pulmonary artery pressure and right atrial pressure, and a decrease in heart rate were observed with dobutamine compared with baseline measurements. Arterial and mixed venous haemoglobin and oxygen content, as well as mixed venous partial pressure of oxygen increased. No significant changes in cardiac output, stroke volume, systemic vascular resistance, arterial partial pressure of oxygen, or oxygen consumption, delivery and extraction ratio were detected. Concluding, dobutamine increased systemic blood pressure without detectable changes in stroke volume, cardiac output or systemic vascular resistance in conscious horses. 相似文献
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Petterino C Guazzi P Ferro S Castagnaro M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):401-404
A 6-year-old, spayed, female, domestic shorthair cat was presented for decreased activity. A nodular lesion was found in the skin extending into the subcutaneous tissue of the right abdominal flank. On lateral and ventrodorsal radiographs of the thorax, an opacity involving the entire right caudal lung lobe and pleural effusion were noted. Cytologic evaluation of cells in the thoracic fluid and in the mass revealed a population of atypical epipthelial cells with marked anisocytosis and high N:C ratios, organized in acinar-like clusters. Multinucleated cells and several mitotic figures were found. The cytologic interpretation was carcinoma. Because of the progressive severity of clinical signs, the cat was euthanized. Histologic evaluation of tissues obtained at necropsy indicated a bronchogenic adenocarcinoma in the lung, with metastasis to the skin of the right flank, but no involvement of the digits. Based on immunohistochemical stains, the neoplastic cells strongly co-expressed cytokeratin and vimentin, and were negative for S-100 and actin-specific antigen. Bronchogenic adenocarcinoma is an uncommon neoplasm in cats, and the digits are the most common sites of metastasis. This case was unusual in that the skin of the abdominal wall was the primary site of metastasis, with no involvement of the digits. 相似文献
8.
Quesada RJ Gorman ME Cebra CK Verdugo C Mosley CA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(2):248-252
Background: Direct colloid osmometry provides an objective assessment of the oncotic effects of crystalloid or colloidal fluid therapy, which is especially useful in monitoring fluid therapy of critically ill camelids due to their tendency toward nonspecific hypoproteinemia with increased risk of developing edema and ascites. Objectives: The aims of this study were to measure colloid osmotic pressure (COP) of alpacas and llamas, determine its correlation with concentrations of total protein (TP) and total solids (TS), as well as both albumin (A) and globulin (G) concentrations in the same model (A+G), and evaluate the effects of sample type and storage conditions on COP. Methods: Blood was collected from clinically healthy alpacas (n=23) and llamas (n=22) into heparin tubes. COP of fresh whole blood (COPFB) and plasma (COPFP) was determined using a membrane osmometer. For 20 alpacas, COP of refrigerated whole blood (COPRB) and frozen plasma (COPFrP) was also measured. Correlations between COPFB and TS, TP, and A+G concentrations were assessed by simple and multiple regression analysis to model potential predictors. Results: Median COPFB from alpacas (24.6 mmHg, range 19.3–28.1) was not significantly different from that of llamas (25.3 mmHg, range 22.5–33.7). Sample type or storage conditions did not affect COP. Measured COP had a strong positive linear correlation with TS, TP, and A+G concentrations in alpacas (r2=.7, .74, and .88, respectively). In llamas, COP correlated best with TS concentration (r2=.59), whereas correlation with TP and A+G concentrations was poor (r2=.19 and .25, respectively). Conclusion: COP can be measured using heparinized whole blood or plasma, either fresh or stored. Direct measurement is recommended whenever quantitative knowledge of COP is required in clinical or research setting. Further studies are needed to verify if the poor association of COP with TP found in this study can be generalized to llamas. 相似文献
9.
Mutinelli F Vercelli A Carminato A Luchesa L Pasolli C Cova M Marchioro W Melchiotti E Vascellari M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(4):527-529
A free-living European red deer calf (Cervus elaphus) was euthanized due to bilateral microphthalmia. Lens was missing, replaced by proliferating squamous epithelial cells; hyperplastic squamous cells, sebaceous and mucinous glands were observed within the cornea with the characteristics of inclusion cyst. Findings were consistent with congenital microphthalmia/aphakia, with multiple eye abnormalities. 相似文献
10.
Marreros N Frey CF Willisch CS Signer C Ryser-Degiorgis MP 《Veterinary parasitology》2012,186(3-4):382-389
To provide baseline parasitological data for health surveillance in free-ranging Alpine ibex (Capra ibex ibex), we assessed the endoparasite population and level of parasitism in apparently healthy ibex. Faecal samples from 148 ibex were collected between 2006 and 2008 in two different Swiss ibex colonies. They were analysed by coprology, including combined sedimentation/flotation method, sedimentation method, Baermann funnel technique and Ziehl-Neelsen staining. Gastrointestinal parasites and lungworms were identified in 100% and 81.8% of the examined animals, respectively. Highest prevalences were recorded for gastrointestinal strongylids other than Nematodirus/Marshallagia spp. (100%), Eimeria spp. (100%), Muellerius spp. (79.8%) and Nematodirus/Marshallagia spp. (79.0%). We report for the first time Cryptosporidium sp. in free-ranging Alpine ibex and Cystocaulus spp. in free-ranging ibex from Switzerland. On average, ibex were infected with 3.9 different parasites taxa (range: 1-8). Parasite prevalence and diversity varied significantly between sexes, study sites and seasons. Parasite egg output was low in 95.7% and moderate in 5.3% of the samples. Overall, the results indicate that Alpine ibex are widely infected with endoparasites and suggest that multiple infections are very common in apparently healthy populations. Furthermore, our data underline the potential influence of factors such as sex, study site and season on parasitological findings. 相似文献