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81.
市电50Hz干扰一直是生理信号检测过程中最难以克服的问题之一。本文叙述了利用同步滤波器技术克服50Hz干扰的方法。同步滤波器可以自动跟踪市电频率的变化且具有极高Q值和理想的梳状滤波特性,而元件的灵敏度却很低,因而很容易获得40dB以上的陷波效果,可以从根本上克服50Hz干扰而几乎对有用信号毫无影响。  相似文献   
82.
目的研究T3期胃癌CD34与胃癌新生血管形成及淋巴结转移的关系.方法随机选取胃癌手术标本41例,其中T3N0M020例,T3N1M021例,分别进行特异性抗体免疫组化染色,并采用Image Pro Plus 5.0图像软件分析数据,计算胃癌组织CD34微血管密度(MVD)和其他相关抗体(CD44、Ⅳ型胶原、层黏蛋白)的表达,并进行统计学分析.结果CD34 MVD计数(CD34表达强度),在T3N0M0和T3N1 M0肿瘤组分别为43.10±18.22和56.24±28.36,两组比较有显著差异(P<0.05);CD44、Ⅳ型胶原、层黏连蛋白的表达强度,T3N0M0和T3N1M0肿瘤组比较无显著差异(P>0.05).结论CD34与T3期胃癌组织新生血管形成及淋巴结转移的关系密切,可作为诊断T3期胃癌淋巴结转移的参考指标.  相似文献   
83.
To determine the prognostic factors for patients with pathological T1 (pT1) carcinoma of the ampulla of Vater, 36 consecutive patients with carcinoma of the ampulla of Vater who underwent surgery were retrospectively analyzed in terms of clinicopathological features. The overall 5-year Kaplan-Meier survival in all patients was 50.2%, and the median survival of all patients was 64.0 months. Factors favorably influencing a long-term outcome were the absence of lymph node metastasis (P<0.0001), the absence of ulcer formation of the tumor (P=0.0062), and the absence of tumor invasion into the duodenum (P = 0.0025) and the pancreas (P=0.0098). In a multivariate analysis, lymph node metastasis was the only predictor of survival (P=0.0023). In the pT1 stage patients, 20% of the patients had lymph node metastasis, and their survival was statistically poor compared to the pT1 patients without lymph node metastasis (P=0.017). As for survival after the operation, there was no significant difference between pancreatoduodenectomy and pylorus-preserving pancreatoduodenectomy.  相似文献   
84.
Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease.  相似文献   
85.
Thirty patients with metastatic breast carcinoma to the liver underwent systemic chemotherapy. Twentyfour of these patients also received hepatic arterial infusion chemotherapy, three in conjunction with hepatic artery embolization. The morphologic changes of the liver believed to be due to chemotoxic effect of treatment occurred in 27 patients, and were evaluated by serial computed tomography (CT) examinations. These included fatty changes in seven patients, severe cirrhotic changes in four, localized atrophy with regional contour changes in three, and areas of low density in the regions of previously treated metastases in 13. The CT features of cirrhosis included density changes along with nodular irregularity of the hepatic borders with marked decrease in liver size and development of ascites.  相似文献   
86.
Metastasis-suppressor genes, by definition, suppress metastasis without affecting tumorigenicity and, hence, present attractive targets as prognostic or therapeutic markers. BRMS1 (breast cancer metastasis suppressor) has recently been identified as a metastasis-suppressor gene for human breast cancer and melanoma. Expression of BRMS1 messenger RNA (mRNA) in multitissue including normal prostate, ovarian, testis, and colon has been detected by northern blot analysis. We hypothesize that the role of BRMS1 in tumor progression may not be limited to breast cancer and melanoma. We previously found that BRMS1 mRNA levels in primary ovarian epithelial carcinomas were significantly lower than that in normal ovarian and benign tumors (P < 0.05), and statistical analysis of BRMS1 mRNA levels revealed that BRMS1 mRNA levels were significantly higher in early tumor stages (I, II) compared with advanced tumor stages (III, IV) in which lymph node or distant metastases were present (P < 0.01). Our data showed that reduced BRMS1 mRNA seems to influence ovarian carcinoma metastatic ability. Therefore, we transfected BRMS1 plasmid into highly malignant ovarian carcinoma cell line, HO-8910PM, and examined cell biologic behaviors including proliferation, adhesion, invasion, and metastasis in vitro and in vivo. BRMS1 expression did not alter the proliferation of HO-8910PM cells in vitro and primary tumor formation in vivo. But, BRMS1 expression significantly suppressed the cell adhesion to extracellular matrix components and in vitro cell invasion in BRMS1-transfected HO-8910PM cells compared to parental HO-8910PM and vector-only transfectants (HO-8910PM-vect). Furthermore, motility of BRMS1 transfectants was inhibited. lung colony formation of intravenously injected BRMS1 transfectants in nude mice was significantly reduced. Also, BRMS1 transfectants form significantly less metastatic to organs of peritoneal cavity in orthotopically implanted ovarian tumor nude models. We further discovered that BRMS1 expression did downregulate expression of an actin-bundling protein associated with cell motility -fascin, which perhaps is the mechanism underlying BRMS1 suppression of metastasis. These data suggested that in addition to its already described role in breast cancer and melanoma, BRMS1 functions as a metastasis-suppressor gene in ovarian carcinoma by modifying several metastatic-associated phenotypes, offering a new target for therapeutic intervention.  相似文献   
87.
Although the transition from early- to advanced-stage ovarian cancer is a critical determinant of survival, little is known about the molecular underpinnings of ovarian metastasis. We hypothesize that microarray analysis of global gene expression patterns in primary ovarian cancer and metastatic omental implants can identify genes that underlie the metastatic process in epithelial ovarian cancer. We utilized Affymetrix U95Av2 microarrays to characterize the molecular alterations that underlie omental metastasis from 47 epithelial ovarian cancer samples collected from multiple sites in 20 patients undergoing primary surgical cytoreduction for advanced-stage (IIIC/IV) serous ovarian cancer. Fifty-six genes demonstrated differential expression between ovarian and omental samples (P < 0.01), and twenty of these 56 differentially expressed genes have previously been implicated in metastasis, cell motility, or cytoskeletal function. Ten of the 56 genes are involved in p53 gene pathways. A Bayesian statistical tree analysis was used to identify a 27-gene expression pattern that could accurately predict the site of tumor (ovary versus omentum). This predictive model was evaluated using an external data set. Nine of the 27 predictive genes have previously been shown to be involved in oncogenesis and/or metastasis, and 10/27 genes have been implicated in p53 pathways. Microarray findings were validated by real-time quantitative PCR. We conclude that gene expression patterns that distinguish omental metastasis from primary epithelial ovarian cancer can be identified and that many of the genes have functions that are biologically consistent with a role in oncogenesis, metastasis, and p53 gene networks.  相似文献   
88.
Background and Aims: Chemokines and their receptors have recently been shown to have major roles in cancer metastasis. The aim of this study was to determine whether the interaction between chemokine receptor 6 (CCR6) and its ligand, macrophage inflammatory protein‐3 alpha (MIP‐3α), correlates with metastasis of hepatocellular carcinoma (HCC). Methods: To observe the reaction of CCR6 expressed cancer cells to MIP‐3α stimulation, chemotactic and actin polymerization assays for both CCR6 high cells (HepG2) and CCR6 low cells (MCF‐7) were performed. CCR6 mRNA levels in tumor specimens from 30 HCC patients were quantified by real‐time polymerase chain reaction. Patients were classified into two groups, high (≥ 20 copies; n = 10) CCR6 and low (<20 copies; n = 20) CCR6 on the basis of CCR6 expression, and the groups were compared with respect to clinicopathological features. Results: When HepG2 cells (CCR6 high) were stimulated with MIP‐3α, they migrated in a dose‐dependent manner, and formation of pseudopodia was observed. These phenomena were not observed in the CCR6 low cells. The incidence of intrahepatic metastasis was higher in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Disease‐free survival was significantly poorer in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Conclusions: It was indicated that CCR6 might be associated with intrahepatic metastasis of HCC and might be able to become one of the prognostic factor after hepatic resection for HCC.  相似文献   
89.
梅军 《安徽医学》2004,25(1):33-35
目的 了解早、中期胃癌的临床、胃镜和病理学特征。方法 回顾性分析我院 11年中经外科手术和病理诊断的 75例早、中期胃癌患者的临床、胃镜、外科手术和病理等方面资料。结果 早、中期胃癌临床表现无特征性 ,男女之比为 2 .41∶1,以 61~ 70岁最多 ,胃窦是其好发部位 ,病理组织学以管状腺癌为多 ,胃镜误诊率是 12 .86%,淋巴转移率是 2 5 .3 3 %。结论 早、中期胃癌有明显的好发年龄和好发部位 ,以管状腺癌为多 ,胃镜误诊的主要原因是不能鉴别病变的良、恶性和准确判断病变量 ,影响淋巴转移的因素是浸润深度、广度、肿瘤大小和年龄 ,而与性别、组织学的分化程度无明显关系。  相似文献   
90.
Metastatic carcinoma of the spleen occurs in a setting of widespread malignant disease. Solitary parenchymal splenic metastasis of ovarian carcinoma is rare. We report a case of a 59-year-old woman who presented with an elevated serum CA125 level due to a solitary splenic metastasis after a long disease-free period. She was treated with laparoscopic splenectomy followed by chemotherapy. The literature contains 16 cases of solitary parenchymal splenic metastasis of ovarian carcinoma. Our case is the third case that was treated with laparoscopic splenectomy. We review the literature, and we focus on the laparoscopic approach in managing these cases.  相似文献   
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