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71.
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc.  相似文献   
72.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination.  相似文献   
73.
We present herein the rare case of a young man who was found to have a solitary tumor in the right upper lobe of his lung by a routine chest X-ray. The tumor was removed by thoracoscopic surgery, and pathological examinations confirmed the diagnosis of a primary lymphangioma of the lung. A brief review of the available literature on this extremely rare type of benign tumor follows the case report.  相似文献   
74.
胰腺肿瘤的B型超声诊断   总被引:4,自引:0,他引:4  
本文将资料完整的并经手术及病理证实的27例胰腺肿瘤初步小结。详细描述各例肿瘤的临床们诊与诊断、B型超声和手术情况,并重点讨论:临床们诊和B型超声未能检出的肿瘤,检出肿瘤大小较手术所见尺寸的要,10mm~40mm以及未见肿瘤浸润的原因。  相似文献   
75.
绝经后阴道出血852例临床分析   总被引:1,自引:0,他引:1  
探讨经经后阴道出血的原因,相关因素来指导临床实践。方法;对我院收治的852例绝经后阴道出血的临床资料进行回顾性分析。结果;以阴道炎最多269例、慢性宫颈炎188例,功能失调性子宫出血102例,宫内节育器98例,恶性肿瘤59例,以内膜癌 33例,卵巢恶性肿瘤次之16例。  相似文献   
76.
本文报告了4例涉及椎体及其后部结构的全椎骨肿瘤的外科治疗,介绍了全椎骨切除术的手术方法及手术注意事项。手术采用后路附件切除,上下椎体Steffee钢板内固定,前路椎体切除自体髂骨植骨融合,初步效果满意。本手术难度大、出血多、危险性高,术中采用控制性低血压,以减少出血。  相似文献   
77.
气管与主支气管肿瘤的影像诊断(附32例报告)   总被引:5,自引:1,他引:4  
作者对32例经病理证实的气管与主支气管良、恶性肿瘤的影像学表现进行分析,归纳为3型:腔内型、壁增厚型和腔内外型。后2种类型提示恶性,而无蒂的腔内型表现者不能鉴别良,恶性。作者还评价了常规体层、CT及MRI诊断气管与主支气管肿瘤的优、缺点,讨论了影像诊断的作用。  相似文献   
78.
陈晓光  大谷周造  李燕  韩锐 《药学学报》1998,33(11):821-827
目的旨在寻找新型抗肿瘤药物,进一步研究d-宁烯、丹参及姜黄素衍生物的抗肿瘤机理。采用分子生物学方法及划痕标记染料示踪技术,研究了4种人实体瘤起源的细胞系的细胞间隙信息传导(GJIC)、H-ras癌基因表达以及ras癌基因产物(P21ras蛋白)表达状态,并观察了4种天然产物对它们的影响。结果表明,细胞内染料传输功能的丧失与ras基因突变率呈正相关;单萜化合物d-宁烯和酚类化合物丹参衍生物的抗肿瘤作用可能与抑制P21ras蛋白膜结合和增强细胞间隙信息传导功能有关。提示Ras癌基因产物P21ras蛋白膜结合的抑制与细胞间隙信息传导功能的增强有直接关系。  相似文献   
79.
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features. These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical studies of both tumors.  相似文献   
80.
Summary With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas (P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93 vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore, be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex Doppler ultrasound and CDFI.  相似文献   
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