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1.
Papillary neoplasms of the breast include a wide spectrum of mammary lesions. The differential diagnosis of benign and malignant lesions can be problematic not only cytologically, but also histopathologically. Aspiration smears can demonstrate that cytological differentiation is feasible. A retrospective study of 30 cases of papillary tumour of the breast, 15 papillary carcinomas and 15 papillomas, was performed to find the cytological differences between the pathologies. Cytological samples of papillary carcinomas were characterized by an abundance of cellular material, three-dimensional papillary clusters without fibrovascular connective tissue cores, small papillae arranged in cell balls, tall columnar cells and isolated naked nuclei. Numerous haemosiderin-laden macrophages were seen. There were no eosinophilic bipolar cytoplasmic granules, bipolar naked nuclei or apocrine metaplasia. In the papillomas there was less material; the papillae had cohesive stalks surrounded by columnar cells in a honeycomb pattern. We also found fewer small papillae and isolated columnar cells. In addition, the presence of apocrine metaplasia and bipolar naked nuclei was noted. We suggest that papillary carcinoma of the breast can be diagnosed by cytology and differentiated from papilloma.  相似文献   
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The occurrence of a second neoplasm is one of the major obstacles in cancer chemotherapy. The elucidation of the genotoxic effects induced by anti-cancer drugs is considered to be helpful in identifying the degree of cancer risk. Numerous investigations on cancer patients after chemotherapy have demonstrated: (i) an increase in the in vivo somatic cell mutant frequency (Mf) at three genetic loci, including hypoxanthine–guanine phosphoribosyl-transferase (hprt), glycophorin A (GPA), and the T-cell receptor (TCR), and (ii) alterations in the mutational spectra of hprt mutants. However, the time required for and the degree of such changes are quite variable among patients even if they have received the same chemotherapy, suggesting the existence of underlying genetic factor(s). Accordingly, some cancer patients prior to chemotherapy as well as patients with cancer-prone syndrome have been found to show an elevated Mf. Based on the information obtained from somatic cell mutation assays, an individualized chemotherapy should be considered in order to minimize the risk of a second neoplasm.  相似文献   
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《Organogenesis》2013,9(2):241-249
Significant achievements in the organ replacement approach for malignancies over the last 2 decades opened new horizons, and the age of “Transplant Oncology” has dawned. The indications of liver transplantation for malignancies have been carefully expanded by a strict patient selection to assure comparable outcomes with non-malignant diseases. Currently, the Milan criteria, gold standard for hepatocellular carcinoma, are being challenged by high-volume centers worldwide. Neoadjuvant chemoradiation therapy and liver transplantation for unresectable hilar cholangiocarcinoma has been successful in specialized institutions. For other primary and metastatic liver tumors, clinical evidence to establish standardized criteria is lacking. Intestinal and multivisceral transplantation is an option for low-grade neoplasms deemed unresectable by conventional surgery. However, the procedure itself is in the adolescent stage. Solid organ transplantation for malignancies inevitably suffers from “triple distress,” i.e., oncological, immunological, and technical. Organ bioengineering and regenerative medicine should serve as the “triple threat” therapy and revolutionize “Transplant Oncology.”  相似文献   
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田厚文  任皎  黄薇  范江涛  赵莉  阮力 《病毒学报》2006,22(5):358-363
采用基因工程方法将HPV16E6、E7基因融合后插入痘苗病毒载体,通过同源重组构建表达人乳头瘤病毒16型E6/E7融合蛋白的非复制型重组痘苗病毒疫苗,用C57BL/6小鼠观察其免疫原性和抗肿瘤移植情况。测序结果表明融合的HPV16E6、E7基因序列与设计相符;构建的非复制型重组痘苗病毒经Dot blot鉴定,显示有E6、E7融合基因的插入;Western blot检测表明该重组病毒在鸡胚成纤维细胞中能表达HPV16型E6/E7融合蛋白。动物免疫试验表明,该重组病毒在小鼠体内可诱发E6、E7特异性抗体;被免疫小鼠能抵抗TC-1肿瘤细胞的攻击。此结果为将来进一步研制HPV16、18型联合疫苗打下了基础。  相似文献   
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目的 观察大鼠诱发肝癌过程中Sonic Hedgehog(Shh)信号通路相关基因的表达变化,探讨其在肝癌发生发展过程中的作用.方法 雄性Wistar大鼠48只,随机分成4组,利用二乙基亚硝胺(DEN)制备诱发性大鼠肝癌模型,应用原位核酸杂交技术检测Shh、Ptc、Gli1 mRNA在对照组、模型组(6w)、模型组(14w)、模型组(22w)大鼠肝脏癌变过程中的表达变化.结果 在模型组(6w)大鼠肝脏的肝小叶周边可见嗜酸性、气球样变性等肝细胞损伤的表现,模型组(14w)大鼠肝脏中可见肝假小叶和非典型增生结节,模型组(22w)大鼠肝脏中可见到高分化的肝细胞癌结节.Shh、Ptc、Gli1 mRNA阳性表达细胞主要分布在大鼠肝脏中的肝细胞损伤区、增生结节、癌结节、小叶间胆管上皮和癌旁组织中,Shh、Ptc、Gli1 mRNA在模型组的大鼠肝组织中表达的平均光密度值均高于对照组.结论 Shh信号通路在诱癌过程中异常激活,可能促进肝损伤后的正常修复、异常增殖及肝细胞癌变过程.  相似文献   
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【摘 要】 目的 探讨hMSH2(human muts homolog2)基因、增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)和结核菌L型感染在前列腺癌中的表达及相关性研究。方法 应用免疫组化和抗酸染色等方法检测了65例前列腺癌(carcinoma of prostate,PCa)和30例良性前列腺增生(benign prostatic hyperplasia,BPH)中的hMSH2、PCNA蛋白的表达以及结核菌L型的检出率,并对前列腺癌主要临床资料和病理分级参数进行比较,用卡方(χ2)检验进行统计学处理。结果 hMSH2、PCNA蛋白在PCa中的表达明显高于BPH(P<0.01)。前列腺癌中临床分期Ⅲ、Ⅳ期hMSH2、PCNA蛋白的表达明显高于Ⅰ、Ⅱ期(P<0.01);随着病理分级增高而显著增加(P<0.01)。结核菌L型的检出率与PCa的病理分级、临床分期差异具有统计学意义(P<0.01~0.05 )。结核菌L型阳性患者中hMSH2表达率[97.2%(35/36)]明显高于结核菌L型阴性患者中hMSH2阳性表达率[31.0%(9/29)];结核菌L型阳性患者中PCNA表达率[94.4%(35/36)]明显高于结核菌L型阴性患者中PCNA阳性表达率[55.2%(16/29)]。结论 hMSH2、PCNA基因在前列腺肿瘤中有不同程度的异常表达,在前列腺癌的发生和发展中起重要的促进作用。结核菌L型感染极有可能导致基因的突变或过表达,因此L型感染可能成为诱发肿瘤形成的原因之一,它们相互协同在前列腺肿瘤发生和发展过程中起重要作用。  相似文献   
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Background: Observational studies have associated metformin use with lower colorectal cancer (CRC) incidence but few studies have examined metformin's influence on CRC survival. We examined the relationships among metformin use, diabetes, and survival in postmenopausal women with CRC in the Women's Health Initiative (WHI) clinical trials and observational study. Methods: 2066 postmenopausal women with CRC were followed for a median of 4.1 years, with 589 deaths after CRC diagnosis from all causes and 414 deaths directly attributed to CRC. CRC-specific survival was compared among women with diabetes with metformin use (n = 84); women with diabetes with no metformin use (n = 128); and women without diabetes (n = 1854). Cox proportional hazard models were used to estimate associations among metformin use, diabetes and survival after CRC. Strategies to adjust for potential confounders included: multivariate adjustment with known predictors of colorectal cancer survival and construction of a propensity score for the likelihood of receiving metformin, with model stratification by propensity score quintile. Results: After adjusting for age and stage, CRC specific survival in women with diabetes with metformin use was not significantly different compared to that in women with diabetes with no metformin use (HR 0.75; 95% CI 0.40–1.38, p = 0.67) and to women without diabetes (HR 1.00; 95% CI 0.61–1.66, p = 0.99). Following propensity score adjustment, the HR for CRC-specific survival in women with diabetes with metformin use compared to non-users was 0.78 (95% CI 0.38–1.55, p = 0.47) and for overall survival was 0.86 (95% CI 0.49–1.52; p = 0.60). Conclusions: In postmenopausal women with CRC and DM, no statistically significant difference was seen in CRC specific survival in those who used metformin compared to non-users. Analyses in larger populations of colorectal cancer patients are warranted.  相似文献   
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