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排序方式: 共有113条查询结果,搜索用时 15 毫秒
1.
应用已建立的鸡肿瘤病快速鉴别诊断技术对源自安徽省5个不同地区的46个鸡群的肿瘤病、抑制病疑似病、死鸡305羽进行检测。结果表明,马立克氏病的阳性率为39.34%(120/305),禽网状内皮组织增生征阳性率为8.52%(26/305),禽白血病阳性率为2.624%(8/305);另对17群未进行MD免疫的肉鸡进行随机抽样检测,其中5个鸡群检测出马立克氏病病毒强毒,阳性率为29.41%(5/17),阳性群的平均检出率为24 %。  相似文献   
2.
High plasma vascular endothelial growth factor (VEGF) concentrations are associated with radiation resistance and poor prognosis. After an exposure to ionizing radiation in cell culture an early phase and a late phase of increased VEGF have been documented. The activation was dependent on the radiation dose. Therefore, the purpose of this study was to measure baseline plasma VEGF and changes in VEGF over the course of fractionated radiation therapy in dogs with spontaneous tumors. Dogs with tumors had a significantly higher pretreatment plasma VEGF than did dogs without tumors. Immediately after irradiation no increased plasma VEGF was observed. Over the course of radiation therapy there was an increased plasma VEGF in dogs treated with low doses per fraction/high total dose, whereas plasma VEGF remained stable in dogs irradiated with high doses per fraction/low total dose. The regulatory mechanisms are very complex, and therefore the value of plasma VEGF measurements as an indirect marker of angiogenesis induced by radiotherapy is limited.  相似文献   
3.
A 4-mo-old northern red-shouldered macaw (Diopsittaca nobilis) was admitted to the veterinary hospital of the Arruda Câmara Zoo, in the State of Paraiba, Brazil, for investigation of an orbital mass. Given rapid progression and lack of response to treatment, the bird was euthanized, and an autopsy was performed. Histologically, the mass consisted of a retrobulbar invasive tumor characterized by tubular and rosette-like structures, with interspersed heteroplastic tissues, such as aggregates of neuroglial cells and islands of hyaline cartilage. The tumor was immunopositive for pancytokeratin, GFAP, NSE, and S100. These findings were compatible with an ocular teratoid medulloepithelioma, a neoplasm best described in humans but also reported rarely in young cockatiels and African Grey parrots.  相似文献   
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5.
以中华鲟(Acipenser sinensis)脑垂体总RNA为模板,采用RT-PCR和RACE方法,获得中华鲟神经内分泌多肽(7B2)基因的3个重叠片段,测序后拼接得到986 bp全长基因序列,其中包括5'端非翻译区(5′-UTR)14 bp、3′端非翻译区(3-′UTR)261 bp和开放阅读框711 bp。翻译编码236个氨基酸。其中前43个氨基酸为7B2的信号肽。经BLAST比对发现中华鲟7B2蛋白的同源性与斑马鱼(Danio rerio)的相似性最高为82%。系统发育分析表明,中华鲟与斑马鱼亲缘关系最近。半定量RT-PCR分析表明:在脑中7B2 mRNA表达量最高,心脏、性腺、胰等组织中表达次之,肠、肾、皮肤等组织中少量表达,肝和鳃几乎不表达。  相似文献   
6.
PRIMARY BONE TUMORS IN THE CAT:   总被引:1,自引:0,他引:1  
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7.
AIM:To investigate endocrine differentiation and its mechanism in endometrial carcinoma.METHODS:Endocrine cells (EC) were identified by immunohistochemical staining of chromogranin A in 50 cases of endometrioid adenocarcinoma and 20 cases of normal endometrium. Double-label techniques were used for simultaneous demonstration of the CgA and cytokeratin.RESULTS:The positive rate of CgA in endometrioid adenocarcinoma was 44.0%, and was significant higher than that in normal endometrium (15.0%, P<0.05). Scanty EC was present in normal endometrium. The number and staining intensity of EC in endometrioid adenocarcinoma were greater than that in normal. Co-expression of CgA and cytokeratin were detected in endometrioid adenocarcinoma.CONCLUSION:The presence of endocrine cells in endometrioid adenocarcinoma showed heterogeneity of tumors. The occurrence of "Multidirectional differentiation cells" within the endometrioid adenocarcinoma may indicate that endocrine cells derive from malignant cells of multidirectional differentiation.  相似文献   
8.
Hemangiosarcoma of the third eyelid in a cat   总被引:2,自引:0,他引:2  
A case of hemangiosarcoma of the third eyelid in a 15-year-old Domestic Short-haired cat is reported. A small red mass protruding from the anterior surface of the third eyelid in the left eye was present. Only mild bilateral conjunctivitis and nuclear sclerosis were revealed on initial ophthalmic examination. After anti-inflammatory treatment, surgery and cryotherapy were performed. On histopathologic examination the mass was located just beneath the conjunctival epithelium, suggesting that the conjunctiva was the tissue of origin. The tumor showed high cellularity and was composed of pleomorphic spindle and polygonal cells arranged in interlacing bundles and solid sheets. The presence of slit-like spaces between tumor cells containing erythrocytes demonstrated the vascular differentiation. Mitotic activity was moderate, but atypical mitoses were detected. The surgical area healed uneventfully and after 7 months there was no recurrence. To the authors' knowledge, this is the first report of conjunctival hemangiosarcoma of the third eyelid in a cat.  相似文献   
9.
A retrospective study of 43 dogs with anal sac adenocarcinoma (ASAC) was performed to characterize the clinical presentation and response to treatment. Clinical signs at presentation varied considerably, with signs related either to sublumbar nodal metastasis (tenesmus or constipation) or hypercalcemia (polyuria-polydipsia and anorexia) being the most frequent findings. At the time of presentation, 23 (53%) dogs had hypercalcemia and 34 (79%) had metastases, with the regional lymph nodes (31 dogs, 72%) being the most common site of metastasis. A variety of chemotherapeutic agents were administered, with partial remission (PR) recorded in 4 of 13 (31%) dogs treated with cisplatin and in 1 of 3 (33%) dogs treated with carboplatin. The median survival for all dogs was 6 months (range, 2 days-41 months). There was no statistical association between the presence of hypercalcemia and survival, although the power of the study to detect an increase in survival of 3 months was low (.33). We conclude that platinum chemotherapy has antitumor activity in canine apocrine gland carcinoma and that further study of these agents is warranted.  相似文献   
10.
Feasibility of delivering a simultaneously integrated boost to canine nasal tumors using helical tomotherapy to improve tumor control probability (TCP) via an increase in total biological equivalent uniform dose (EUD) was evaluated. Eight dogs with varying size nasal tumors (5.8-110.9 cc) were replanned to 42 Gy to the nasal cavity and integrated dose boosts to gross disease of 45.2, 48.3, and 51.3 Gy in 10 fractions. EUD values were calculated for tumors and mean normalized total doses (NTD(mean)) for organs at risk (OAR). Normal Tissue Complication Probability (NTCP) values were obtained for OARs, and estimated TCP values were computed using a logistic dose-response model and based on deliverable EUD boost doses. Significant increases in estimated TCP to 54%, 74%, and 86% can be achieved with 10%, 23%, and 37% mean relative EUD boosts to the gross disease, respectively. NTCP values for blindness of either eye and for brain necrosis were < 0.01% for all boosts. Values for cataract development were 31%, 42%, and 46% for studied boost schemas, respectively. Average NTD(mean) to eyes and brain for mean EUD boosts were 10.2, 11.3, and 12.1 Gy3, and 7.5, 7.2, and 7.9 Gy2, respectively. Using helical tomotherapy, simultaneously integrated dose boosts can be delivered to increase the estimated TCP at 1-year without significantly increasing the NTD(mean) to eyes and brain. Delivery of these treatments in a prospective trial may allow quantification of a dose-response relationship in canine nasal tumors.  相似文献   
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