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671.
672.
Eyelid squamous cell carcinoma in equine patients often presents a therapeutic challenge to practitioners due to the generally large area affected upon presentation. Surgical excision can be curative if wide enough margins are achieved, but this is not often attainable without enucleation. Other alternatives have been examined including cryotherapy, radiotherapy, brachytherapy, intralesional chemotherapy and photodynamic therapy. Intralesional chemotherapy using cisplatin, mitomycin‐C and bleomycin have been shown to be successful in treating eyelid squamous cell carcinomas but may be prohibitive to some owners due to the cost of therapy. To the authors' knowledge, this is the first case series to illustrate the effectiveness of intralesional 5‐fluoruracil in treating large equine eyelid squamous cell carcinomas. Macroscopic reduction in the size of the affected areas was noted in each case together with regression of clinical signs associated with the mass. This, coupled with the relative inexpensive nature of the procedure, makes this technique an attractive therapy for either primary treatment of eyelid squamous cell carcinoma or as a cytoreductive technique prior to surgical excision.  相似文献   
673.
The purpose of this study was to determine the utility of triple‐phase helical computed tomography (CT) for differentiating canine hepatic masses. Seventy dogs with hepatic masses underwent triple‐phase CT followed by surgical removal of the hepatic masses. Triple‐phase helical CT scans for each dog included precontrast, arterial phase, portal venous phase, and delayed phase studies. The removed hepatic masses were histopathologically classified as hepatocellular carcinoma (n = 47), nodular hyperplasia (n = 14), and hepatic metastatic tumors (n = 9) in dogs. Of the 47 hepatocellular carcinomas, the most common CT findings included a heterogeneous pattern with hyper‐, iso‐, and hypoenhancement in both the arterial and portal venous phases (40/47, 85.1%). Of the 14 nodular hyperplasias, the most common CT findings were a homogeneous pattern with hyper‐ and isoenhancement in both the portal venous and delayed phases (13/14, 92.9%). Of nine hepatic metastatic tumors, the most common CT findings included a homogeneous hypoenhancement pattern in both the arterial and portal venous phases (8/9, 88.9%). In addition, 5 (55.6%) showed homogeneous hypoenhancement patterns in the delayed phase. Findings from our study indicated that triple‐phase CT is a useful tool for preoperative differentiation of hepatocellular carcinoma, nodular hyperplasia, and hepatic metastatic tumors in dogs.  相似文献   
674.
Squamous cell carcinoma (SCC) accounts for approximately 10% of all feline tumors. The purpose of this retrospective study was to describe outcomes for a group of cats with oral SCC that were treated with palliative radiation therapy. Fifty‐four cats met the inclusion criteria of nonresectable, oral SCC treated with coarse fractionated megavoltage (MeV) radiation therapy. Radiation therapy for all cats was delivered with a 6 MeV linear accelerator. Total radiation doses of 24 Gray to 40 Gray were administered in three to four fractions, once‐per‐week over 4 to 5 weeks. Concurrent chemotherapy protocols varied and were administered at the discretion of the clinician and client. Forty‐nine patients completed the planned treatment protocols. Overall mean and median survival times for cats completing the planned treatment protocols were 127 and 92 days (n = 49). Mean and median survival times of cats receiving palliative radiation therapy alone were 157 and 113 days (n = 12). Mean and median survival times of patients receiving both radiation therapy and chemotherapy were 116 and 80 days (n = 37). Patients with sublingual tumors had a median survival time of 135 days (n = 15), compared to mandibular tumors that had a median survival time of 80 days (n = 26). For the majority of patients that completed the planned treatment protocol (65%), owners reported a subjectively improved quality of life. Findings from this uncontrolled study supported the use of palliative radiation therapy for cats with nonresectable oral squamous cell carcinoma.  相似文献   
675.
This report describes the gross, histological, and immunohistochemical features of medullary thyroid carcinoma (MTC) with pulmonary metastases in a young dog. Sheets of pleomorphic cells supported by fibrous stroma characterized the primary mass, while metastatic nodules had a neuroendocrine pattern. Despite differing histologic features, all masses showed marked immunoreactivity against calcitonin and multiple neuroendocrine markers consistent with MTC. Although MTC is a well-recognized entity, it may be difficult to distinguish this mass from other thyroid neoplasms, necessitating immunohistochemical characterization.  相似文献   
676.
A retrospective evaluation of 232 feline nasal biopsies initially diagnosed as either carcinoma or lymphoma was performed by two pathologists. One or both pathologists disagreed with the original diagnosis in 15 cases (7%), 14 of which had original diagnoses of carcinoma. Out of the 232 cases, 140, including the disputed ones, were subjected to immunohistochemical staining with epithelial and lymphoid markers. Immunohistochemical staining of the 15 disputed cases showed that the original diagnoses were incorrect in 67% (10/15), unverified in 13% (2/15) and correct in 20% (3/15). Among the consensual diagnoses, immunohistochemistry revealed that 3% (4/125) of diagnoses were unverified because they did not stain for any of the markers evaluated. This report demonstrates the importance of immunohistochemistry in establishing a correct histologic diagnosis for nasal neoplasms in cats.  相似文献   
677.
采用单管法一步完成端粒重复序列扩增法检测人肝癌细胞株,经不同浓度JA1及不同时间的作用前后端粒酶活性的变化,并采用流式细胞仪分析细胞周期的变化。结果显示,JA1可显著抑制人肝癌细胞端粒酶活性,而且这种抑制效果有剂量依赖性和时间依赖性。流式细胞仪分析细胞周期的变化表明,端粒酶活性被抑制后,肝癌细胞被阻滞在G2/M。同时,在检测标本中显示有明显的DNA低含量颗粒(“亚G1期”峰),表明肝癌细胞凋亡的存在。  相似文献   
678.
CD44 is an adhesion molecule implicated in the progression of human breast cancer. The purpose of this study was to describe CD44 antigen expression in canine mammary carcinomas and to evaluate its prognostic significance in relation to other clinico-pathological variables.A reduction in CD44 expression was significantly related to variables such as tumour size and adherence to underlying tissues but was not related to tumour location or to ulceration of the overlying skin. Complex (grade I) and anaplastic (grade III) carcinomas exhibited more intense expression of this antigen than did some tubulopapillary and most solid carcinomas (grade II). Although reduced CD44 expression was associated with infiltrative growth and vascular invasion in solid carcinomas, intense expression was also observed in anaplastic tumours. Although overall these findings suggest a role for this adhesion factor in canine mammary tumour development and progression, the complexity and apparently paradoxical nature of some of the findings currently limit the use of this immunohistochemical marker as a prognostic indicator.  相似文献   
679.
A 4-year-old, castrated, male domestic ferret (Mustela putorius furo) was evaluated for a possible upper respiratory tract infection and wheezing for approximately 3 weeks. Supportive care for a suspected upper respiratory tract infection was initiated; however, the patient became progressively more dyspneic over the next 48 hours. A possible tracheal mass was identified upon thoracic radiographic imaging of the ferret. Tracheoscopy and a computed tomography scan of the neck and thorax confirmed the presence of a tracheal mass approximately 3 cm from the larynx obstructing 80% of the tracheal lumen. Rather than pursuing surgical resection, the owners elected humane euthanasia. An adenosquamous carcinoma of the trachea was diagnosed after histologic analysis. This tumor type has been diagnosed in the lungs of ferrets that were experimentally exposed to carcinogens found in cigarette smoke; however, there are no previous reports of this or any other tumor type associated with the ferret trachea. A tracheal mass causing a partial upper airway obstruction should be considered within the differential disease diagnosis list when a ferret is presented with dyspnea.  相似文献   
680.
目的:比较3种不同的耳后野照射方案治疗鼻咽癌的疗效。方法:90例茎突后间隙受犯的鼻咽癌初治患者,第l段放疗采用面颈联合野放疗,第2段放疗采用耳前野加耳后野放疗。按第2段放疗耳后野不同照射时间、分次剂量随机分为3组:常规剂量组(n=30)、低剂量组(n=31)和后加量组(n=29)。常规剂量组耳后野剂量为每次2Gy,与耳前野相隔6h后照射;低剂量组耳后野剂量为每次lGy,与耳前野相隔6h后照射;后加量组为耳前野照射结束后耳后野照射,每次剂量为2Gy;3组耳后野放疗剂量为10--20Gy,放疗总剂量为肿瘤量(DT)68—80Gy。结果:常规剂量组、低剂量组和后加量治疗3个月后完全缓解率(CR)分别为83.3%、90.3%和82.8%,差异无显著性(P>0.05);而中耳炎发生字分别为71.9%、47.4%和44.4%.Ⅲ-Ⅳ级口腔粘腰反应发生率分别为53.3%、28.8%和17.2%,常规剂量组与低剂量组或后加量组比较,差异均有显著性(P值均为<0.05)、但低剂量组与后加量组比较差异无显著性(P>0.05)。结论:耳后野低剂量或后加量放射治疗方案的疗效稳定且毒副反应较低。  相似文献   
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