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91.
本文对6例乳腺导管扩张症进行了临床病理报道,6例术前皆被误诊乳腺其他疾病,根据此种情况作了如何正确诊断的阐述.提出了常见误诊病例如何鉴别。  相似文献   
92.
Evidence from both experimental carcinogenesis and studies in human cirrhotic liver suggest that defective repair of the promutagenic DNA base lesion, O 6-methylguanine, is a factor in the multistep process of hepatocellular carcinogenesis. Ubiquitous environmental alkylating agents such as N-nitroso compounds can produce O 6-methylguanine in cellular DNA. Unrepaired, O 6-methylguanine can lead to the formation of G ? A transition mutations, a known mechanism of human oncogene activation and tumour suppressor gene inactivation. Combined treatment of rodents with an agent producing O 6-methylguanine in DNA, and an agent promoting cell proliferation, leads to development of hepatic nodules and hepatocellular carcinoma (HCC), cell division, hence DNA replication, being required for the propagation of tumorigenic mutation(s) in hepatocyte DNA. The paramount importance of O 6-methylguanine in hepatocellular carcinogenesis is indicated by the observation that transgenic mice engineered to have increased hepatic levels of repair enzyme O 6-methylguanine-DNA methyltransferase (MGMT) are significantly less prone to hepatocellular carcinogenesis following alkylating agent treatment. Cirrhosis is a universal risk factor for development of human HCC, and a condition that is characterized by increased hepatocyte proliferation as a result of tissue regeneration. Levels of the human repairing enzyme for O 6-methylguanine were found to be significantly lower in cirrhotic liver than in normal tissue. In accord with findings from animal models, this suggested a mechanism in which persistence of O 6-methylguanine due to defective DNA repair by MGMT, together with increased hepatocyte proliferation, might lead to specific gene mutation(s) and hepatocellular carcinogenesis. Screening for the presence and persistence of O 6-methylguanine in human DNA presently involves formidable technical difficulty. Indications are that such limitations might be overcome by the use of an ultrasensitive method such as immuno-polymerase chain reaction (PCR). This approach should allow parallel measurement of DNA adduct and repair enzyme in routine liver biopsy samples. It might also enable investigation of O 6-methylguanine in human genes specifically associated with hepatocellular carcinogenesis. Given the wide variation in human MGMT levels observed between individuals, tissues, and cells, this technology should be adapted to permit the ultrasensitive localisation and measurement of adducts and repairing enzyme in liver biopsy tissue sections. Ability to ultrasensitively measure O 6-methylguanine, and its repair enzyme, should prove valuable in the risk assessment of cirrhotic patients for developing hepatocellular carcinoma. Received for publication on July 6, 1998; accepted on Aug. 12, 1998  相似文献   
93.
94.
An extensive review of the currently available literature on primary fallopian tube carcinoma is presented. The role of vaginal ultrasonography and the importance of an aggressive evaluation of every tubal deformity is stressed. A staging system which takes into account recent data on the biology of this malignancy is proposed. We emphasize the largely underestimated importance of early lymphatic spread of this disease, necessitating a thorough staging laparotomy with pelvic and para-aortic lymph node sampling in the apparent early stages. The need for adjuvant treatment is obvious, but until now no firm data exist as to what the optimal strategy should be. We recommend that until more representative studies are available, ovarian carcinoma protocols should be used in clinical practice.  相似文献   
95.
超液化碘油混合抗癌药物栓塞治疗中晚期肝癌   总被引:1,自引:0,他引:1  
本文报告超液化碘油混合抗癌药物经皮肝动脉栓塞治疗51例中晚期肝癌。术后50例临床病情改善,治疗2次后肿瘤显著缩小(>50%)16例,中度缩小(20~50%)21例,轻度缩小(<20%)7例;5例为弥漫型难以判定肿块大小,另2例未复查。所有肿瘤缩小的病例均可见肿瘤血管减少。治疗后3个月、6个月、9个月和1年以上生存率分别为100%、82.4%、59.8%和23.5%,其中生存期大于9个月者均为团块型或多结节型。  相似文献   
96.
We report a case of metastatic lobular breast carcinoma with extrahepatic gastrointestinal disease. On the basis of clinical findings, radiologic investigations, computerized axial tomography, gastrointestinal endoscopy, and gastric biopsy, the diagnosis of gastric and ileal Crohn's disease was made. The correct diagnosis of peritoneal carcinomatosis was made at laparoscopy. This case exemplifies the utility of laparoscopy in establishing the diagnosis and staging for abdominal disease of uncertain etiology.  相似文献   
97.
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically, the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes. The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma.  相似文献   
98.
Secretory (so-called juvenile) carcinoma of the breast, first described in children, occurs also in adult women, predominantly in the third decade. Less commonly it is seen in older age groups, up to the eighth decade. We report five patients with this tumour; one, a female aged 73, is the oldest age at which the tumour has been recorded, and one is the first report in an adult male in whom the disease recurred after 20 years, only the second recorded death attributable to this tumour type. Secretory carcinoma in adults is potentially more aggressive than in childhood. Nodal metastases are more frequent and sometimes more extensive. Recurrence of tumour after surgery developed in four of our five patients at 3, 8, 15 and 20 years. Slow growth and delayed recurrence are characteristic of many of these tumours. Death from systemic metastases is rare, but may ensue either rapidly or following a long latent period after treatment. Prolonged follow-up is needed to assess accurately the biological behaviour of this tumour.  相似文献   
99.
Summary Most series in Africa show a high percentage of hepatitis B surface Hepatitis antigen in hepatocellular carcinoma. Two groups of cases were investigated in this study. The one was derived from the autopsy material at Baragwanath hospital from subjects who had lived in Soweto, a large Black urban town. The second group consisted of male Black mineworkers generally originating from rural areas. A combination of the aldehydefuchsin stain and immunoperoxidase technique was used. The two groups showed totally different results. The Baragwanath series consisted of 24 hepatocellular carcinomas of which only 4 (17%) were HBsAg positive. Of the 24 cases, 14 had cirrhosis of which 9 were macronodular and 5 micronodular. Ten of these cases showed heavy iron overload. The series of male Black mineworkers comprised 22 cases of which 16 (72%) were HBsAg positive. Twelve of the 22 cases showed a macronodular cirrhosis and there were no micronodular cirrhoses. Only one case showed severe iron overload. These findings delineate two different populations of hepatocellular carcinoma in Southern Africa.  相似文献   
100.
We present a case of Merkel cell carcinoma of the thigh diagnosed by conventional histology, immunohistochemistry, electron microscopy and cytogenetics. A unique chromosome 6 trisomy characterized this primary neoplasm, as confirmed by FISH study. The role of chromosome analysis and interphase cytogenetics is emphasized as an adjunct in the subtyping of tumours and their prognostic evaluation.  相似文献   
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