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Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
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We have developed a non-invasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers. In this study, we used the rat colon carcinogenesis model to determine if changes in fecal protein kinase C (PKC) expression have predictive value in monitoring the neoplastic process. Weanling rats were injected with saline or azoxymethane (AOM) and 36 weeks later fecal samples and mucosa were collected, poly A+ RNA isolated, and quantitative RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and zeta mRNA levels were altered by the presence of a tumor, with tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII expression as compared with animals without tumors. In addition, AOM-injection increased mucosal PKC betaII mRNA expression compared with saline controls. No effect of tumor incidence on mucosal PKC betaII expression was observed. In contrast, fecal PKC zeta expression was 2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus saline. Since tumor incidence exerts a reciprocal effect on fecal PKC betaII and zeta mRNA expression, data were also expressed as the ratio between PKC betaII and zeta. The isozyme ratio was strongly related to tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25, animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that the expression of fecal PKC betaII and zeta may serve as a noninvasive marker for development of colon tumors. A sensitive technique for the detection of colon cancer is of importance since early diagnosis can substantially reduce mortality.   相似文献   
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氯地滴眼液的含量测定   总被引:4,自引:0,他引:4  
目的:采用HPLC法测定氯地滴眼液中氯霉素和地塞米松磷酸钠的含量。方法:色谱分析条件:ODS柱作分析柱,流动相为甲醇/水体系,0 ̄8min使用40%甲醇,8 ̄16min使用60%甲醇,流速1ml/min,0 ̄9min240nm紫外检测,:二组分分离良好。各组各组性关系良好,平均回收率氯霉素99.8%(RSD=1.2%,n=5),地塞米松磷酸钠99.4%(RSD=0.7%,n=5),结论:该法用于氯  相似文献   
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目的 报告成功实施腹腔镜迷你胃旁路术治疗单纯性肥胖并2型糖尿病病人1例。方法 第二军医大学附属长海医院微创外科于2007年11月对1例伴有2型糖尿病的单纯性肥胖症病人行腹腔镜迷你胃旁路术。结果 病人手术顺利,手术时间135min,术中出血20mL。术后30d内无手术并发症,随访30d,体重下降15kg,体重指数(BMI)减少4.9。术后第8天停用一切降糖药物,各项糖尿病检查指标均正常。结论 腹腔镜迷你胃旁路术是相对安全、简单的术式,近期减重效果良好,对2型糖尿病具有很好的治疗效果。  相似文献   
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Recently, there has been considerable interest and debate over the application of minimally invasive surgical approaches to primary total hip arthroplasty. The 2-incision technique employs intermuscular and internervous planes to gain access to the hip joint while minimizing the disruption of muscles and tendons. Through the anterior incision, the femoral neck is osteotomized and the head removed, followed by preparation and cementless reconstruction of the acetabulum. The posterior incision permits femoral preparation and reconstruction with a cementless stem. The potential benefits of this technique include decreased perioperative blood loss and pain, more rapid recovery of hip function and return to normal activity, a reduced length of hospital stay, and cosmetically appealing small scars. Other essential considerations include appropriate patient selection, adherence to surgical principles, and familiarity with specialized instruments and implants.  相似文献   
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