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21.
This case report describes a case of spontaneous pancreatic islet cell carcinoma with vascular invasion in a 110-week-old male F344 rat. Histologically, a pancreatic nodule consisting of tumor cells and many blood-rich vessels, and covered with a fibrous capsule showed local invasion in the capsule and adjacent acinar tissues, encircling a large duct-like structure (DS). The tumor was composed of well-differentiated tumor cells resembling normal pancreatic islet cells, which had small round nuclei and eosinophilic cytoplasm. Mitotic figures were rare. Immunohistochemistry revealed that the tumor cells were positive for insulin. Although endothelial cells were not detected, the DS wall showed cells positive for α-smooth muscle actin and elastic fibers, suggesting that the DS is the pancreatic artery. This is a rare case of islet cell carcinoma consisting of well-differentiated tumor cells with invasion of the pancreatic artery in a rat.  相似文献   
22.
[目的]研究山核桃果皮提取物抗肿瘤活性。[方法]采用提取及萃取过程制备山核桃果皮提取物分离化合物,选取人肝癌SMMC-7721细胞及人宫颈癌Hela细胞为模型,测定山核桃果皮提取物对肿瘤细胞的抑制作用。[结果]从山核桃果皮所提取出的化合物具有一定的体外增殖抑制作用。[结论]山核桃果皮提取物是一种安全有效的抗肿瘤活性物质。  相似文献   
23.
[目的]探讨金槐米槲皮素对人鼻咽癌CNE2细胞的干预作用。[方法]通过微波辅助提取法从桂北金槐米中提取槲皮素并纯化,用浓度20、40、60和80μmol/L的槲皮素作用于人鼻咽癌细胞CNE2;分别在24、48和72 h后,采用MTT法初步检测人鼻咽癌细胞被抑制的情况,用流式细胞术分析其细胞周期和凋亡率、光学显微镜观察细胞形态学变化。[结果]从槐米中提取的槲皮素对鼻咽癌细胞有明显的抑制作用,且呈浓度、时间明显的依赖性,药物干预作用的最适浓度为60μmol/L,药物干预后形态学观察的最适宜时间为48 h。细胞周期分析显示,槲皮素能阻滞鼻咽癌细胞于G1期。[结论]从桂北金槐米中提取的槲皮素对人鼻咽癌细胞有较强的干预作用。  相似文献   
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25.
ansitional cell urethral carcinoma in four female dogs is reported. Lesion distribution in the proximal two thirds of the urethra and the radiographic appearance with retrograde positive contrast urethrography were similar in each dog. The normally smooth longitudinal urethral striations were replaced by multiple small, poorly marginated intraluminal masses that resulted in a generalized moth-eaten appearance. Extension of contrast medium into the periurethral tissues also occurred. Retrograde urethrography, a simple diagnostic technic, aided in establishing a differential diagnosis in dogs that had urine retention and stranguria.  相似文献   
26.
This report describes a squamous cell carcinoma in a 1-year-old female veiled chameleon (Chamaeleo calyptratus). The lesion developed as a small (1 by 1 mm) left periocular discoloration of a scale never involving the eye. The mass was first diagnosed as an abscess, increased in size (4 by 8 by 3 mm), and recurred after two surgical resections combined with antibiotic therapy. Poor nutritional condition and egg production by the chameleon complicated management of this condition. The mass was removed surgically a third time at which point histopathologic evaluation revealed a locally invasive squamous cell carcinoma. Bacterial culture of the mass isolated a pure culture of Pseudomonas aeruginosa. Ceftazidime was administered at 20 mg/kg IM every 48 h for 20 days. The animal died 3 months later from complications during an ovariohysterectomy for pregnancy toxemia and oviduct inertia. Necropsy showed no local recurrence or metastasis of the tumor.  相似文献   
27.
Ocular and periorbital sarcoids and squamous cell carcinoma are common in equine practice. Extensive involvement of periorbital tissues often necessitates removal of the globe if the function of the eyelids can not be maintained with tumor removal alone. This report describes a modification of the standard enucleation or exenteration technique for cases in which there is insufficient skin to achieve primary closure following complete surgical excision. The caudal portion of the dorsal orbital rim is protuberant; partial excision with an osteotome facilitates skin closure by decreasing the size of the wound. Mesh expansion of skin via multiple rows or parallel stab incisions can also be used as an adjunct to facilitate closure. Four horses underwent enucleation or exenteration using the orbital rim resection and mesh skin expansion techniques for extensive periocular tumors that were unresponsive to prior treatments. Follow-up intervals ranged from 6 to 42 months and no horses had tumor regrowth.  相似文献   
28.
A case of renal tubular carcinoma with bone metaplasia is reported in a 20-year-old male, mixed breed horse having a history of weight loss and hematuria. This report includes the clinical signs, macroscopic and microscopic lesions, and the immunohistochemical findings of this neoplasm.  相似文献   
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30.
The response of advanced stage cutaneous squamous cell carcinomas (SCC) following treatment with photodynamic therapy (PDT) has been poor. It was the aim of this pilot study to determine whether an increase in the delivered fluence (i.e. energy density) would improve the duration of tumour remission in cats with advanced-stage SCC. Tumours were treated with aluminium phthalocyanine tetrasulphonate (AlPcS4) PDT at a fluence of either 100 J cm−2 or 200 J cm−2 and tumour response was evaluated at regular intervals. Those feline tumours treated with a fluence of 100 J cm−2 ( n = 8) had a significantly shorter median remission duration (69 days; range 0–619 days) than those feline tumours treated with 200 J cm−2 ( n = 6; 522 days; range 151–1057 days). It is our conclusion that a fluence of 200 J cm−2 is well tolerated and more effective when treating cats with advanced stage cutaneous SCC.  相似文献   
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