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51.
目的观察谷氨酸脱羧酶67-绿色荧光蛋白(GAD67-GFP)基因敲入小鼠三叉神经尾侧亚核(Vc)浅层内,表达GFP的GABA能神经元的分布及其与小白蛋白(PV)的共存。方法分别运用原位分子杂交与免疫组织化学相结合;GFP与神经元标记物——神经元核蛋白(NeuN)或PV免疫荧光染色相结合的双重标记方法,在光学显微镜和激光共聚焦显微镜下进行观察。结果1.Vc浅层内90%以上的GFP阳性神经元同时表达GAD67 mRNA,而几乎所有表达GAD67 mRNA的阳性神经元都呈GFP阳性;2.GFP阳性神经元主要分布于Vc的Ⅰ-Ⅱ层内,细胞较小,尤其在Ⅱ层内可见大量密集分布的GFP阳性细胞和突起。GFP阳性神经元分别占Ⅰ、Ⅱ层内NeuN阳性神经元总数的19.4%和24.3%;3.GFP/PV双标神经元主要分布于Vc的Ⅰ-Ⅱ层,这些双标神经元大约占PV阳性神经元的62.4%,占GFP阳性神经元的12.8%。结论在Vc表达GFP的GABA能神经元主要密集分布于与外周伤害性信息传递关系密切的板层内,且大部分PV样阳性神经元属于GABA能神经元。  相似文献   
52.
声带鳞状细胞癌早期改变的病理学观察   总被引:1,自引:0,他引:1  
目的探讨声带鳞状细胞癌早期病理学的特点,提高病理诊断水平。方法总结89例声带鳞状细胞癌早期改变病例的病理资料,对其石蜡切片进行HE染色、PAS染色及p53、Ki-67免疫组化染色;以59例声带角化症(分为单纯增生组40例和异型增生组19例)和30例声带浸润癌(浸润深度〉3mm的癌)作为对照。结果在HE染色下,声带鳞状细胞癌的早期改变可区分为两种类型:Ⅰ型为上皮全层癌变型,占67.4%(60/89);Ⅱ型为上皮基底层及副基底层癌变型,占32.6%(29/89),又可分为Ⅱa和Ⅱb两个亚型。HE染色显示有可疑微小浸润者52例,PAS染色示其中的43例(83%)的可疑病灶周边基膜样物质消失,有微浸润,Ⅰ型微浸润的比例较Ⅱ型明显偏低(P=0.007)。HE染色下3例(3.4%,3/89)认为无微浸润者经深切证实有浸润,并经PAS染色确认。Ⅰ型和Ⅱ型的p53表达率差异无显著性(P=0.445),而Ki-67阳性率Ⅰ型高于Ⅱ型(P=0.048)。癌早期改变组的p53阳性率高于声带角化症伴单纯增生组(P=0.008),而与声带角化症异型增生组和声带进展癌组之间的差异无统计学意义(P=0.240,P=0.268)。癌早期改变组的Ki-67阳性率明显低于浸润癌组(P=0.000),并明显高于角化症伴单纯增生组(P=0.001),但与角化症伴异型增生组之间差异无显著性(P=0.248)。结论声带鳞状细胞癌早期改变可区分为Ⅰ型和Ⅱ型,Ⅱ型癌变可在不累及上皮全层的情况下,由上皮的基底层和(或)副基底层细胞直接向固有膜内增生及癌变,此型占全部病例的近1/3,早期浸润是Ⅱ型诊断的可靠依据;Ⅱ型的存在提示声带鳞状细胞癌的早期发生和演进可能存在不同的机制;PAS染色和p53、Ki-67免疫组化染色有助于声带鳞状细胞癌Ⅱ型早期的诊断。  相似文献   
53.
The increasing availability of means for the early detection of prostatic cancer has brought under scrutiny the criteria used for prognosis and emphasized our limitations in understanding what determines the rate of progression in these cancers. The rate of cancer cell proliferation has been under intense investigation, which, however, has yielded conflicting results. In this study we evaluated the proliferative activity of benign and neoplastic prostatic epithelium, using various existing methodologies. We first analysed the variability introduced by the methodological approach and then attempted to demonstrate whether determination of the proliferative capacity had any clinical consequence that complemented the histological grading. Tissue samples from patients, 88 with cancer and 46 with benign prostatic pathology, were studied using in vitro bromodeoxyuridine (BrdU) incorporation as well as Ki67 and the proliferating cell nuclear antigen (PCNA) to estimate the proliferative activity. Increased proliferation was found consistently in inflammation and metaplasia, but not in hyperplasia. In contrast, cancers showed marked variability. Although average proliferation indices increased with grade, there was a wide scatter of values. Correlation was stronger with stage, but also depended on the methodology. Bromodeoxyuridine indices over 10 per mille had a positive predictive value of 79 per cent for cancers extending beyond the prostatic capsule and may prove particularly helpful for evaluating patients with grade 7 cancer. This observation is significant, since grade 7 cancers are the most frequent and the least predictable.  相似文献   
54.
55.
Li SS  Xue WC  Khoo US  Ngan HY  Chan KY  Tam IY  Chiu PM  Ip PP  Tam KF  Cheung AN 《Histopathology》2005,46(3):307-313
AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients.  相似文献   
56.
影响肝细胞癌生物学行为及预后的相关因子分析   总被引:2,自引:0,他引:2  
目的探讨影响肝癌生物学行为及预后的重要因素和寻求肝癌基因治疗的有效靶点。方法运用免疫组化方法检测Ki67、nm23H1、cMet及MT1MMP蛋白在93例肝细胞癌组织中的表达水平,并判断其与肝癌细胞恶性生物学行为及患者预后的关系。结果Ki67、nm23H1、cMet及MT1MMP蛋白表达水平与肝癌患者预后均具有显著相关性(P均<0.01);nm23H1的表达与肿瘤远处转移之间呈负相关关系(P=0.041);cMet、MT1MMP的表达与肝癌瘤旁浸润及远处转移之间均呈正相关关系(P<0.05)。结论nm23H1基因的失活或突变,伴随cMet以及MT1MMP蛋白的异常表达可能是导致肝癌浸润、转移的关键因素。  相似文献   
57.
After bone marrow (BM) or solid-organ (SO) transplantation viremic Cytomegalovirus (CMV) infection is observed frequently. Quantitative assay of CMV in blood helps the management of this clinical condition. In the present report, 83 samples from 39 solid organ recipients, three CMV assays were compared simultaneously for the first time: the Nuclisens CMV pp67 assay (nucleic acid sequence-based amplification, NASBA), an "in-house" quantitative real-time PCR assay (TaqMan) for CMV DNA, and pp65 antigenemia. The relation between CMV DNA and pp65 antigenemia, the quantitative assays, was evaluated on a larger group including 251 blood samples from 118 solid organ recipients. Real-time PCR provided the best results; > or =130 CMV DNA copies/2 x 10(5) peripheral blood leukocytes (PBLs) predicted > or =1 pp65 antigen positive (Ag+) cell/2 x 10(5) PBLs. By taking pp65 antigenemia as the "gold standard," the sensitivity of CMV DNA quantitation and of the pp67 RNA assay were 0.95 and 0.20, respectively, while the corresponding specificity values were 0.50 and 0.93. When real-time PCR was considered as the "gold standard," the sensitivity and specificity of the pp65 antigenemia were 0.65 and 0.91, respectively. Among the three tests examined, the sensitivity of the pp67 RNA assay was the lowest. On the other hand, the pp67 RNA assay was highly specific and effective in pinpointing high viremia patients. The present report, by providing predictive values for all three diagnostic profiles, DNA load, antigenemia, and pp67RNA, is a contribution for validation of real-time PCR as a new standard for quantitative assessment of CMV viremia in clinical settings.  相似文献   
58.
子宫内膜癌中Rb2/P130、PTEN及Ki-67的表达及意义   总被引:2,自引:0,他引:2  
目的 探讨正常子宫内膜、子宫内膜增殖症及内膜癌组织中Rb2/P130、PTEN及Ki-67的表达以及与子宫内膜癌发生的关系.方法 应用免疫组化SP法检测30例正常子宫内膜组织、32例单纯型增生过长、31例复杂型增生过长、36例不典型增生、64例子宫内膜癌组织中Rb2/P130、PTEN和Ki-67的表达.结果 Rb2/P130、PTEN蛋白在正常子宫内膜、单纯性增生过长、复杂型增生、不典犁增生、子官内膜癌组织中的阳性表达率依次递减,而Ki-67的阳性表达率依次递增,子宫内膜癌和不典型性增生中Rb2/P130、PTEN阳性表达率明显低于正常增生期子宫内膜和单纯性增生,差异均有显著性(P均<0.01),而Ki-67的阳性表达率明显高于正常增牛期子宫内膜和单纯性增生过长,差异均有显著性(P均<0.01).Rb2/P130、PTEN阳性表达缺失与组织学分级有关(P均<0.01)、与子宫肌层浸润程度无关,Rb2/P130阳性表达缺失与淋巴结转移无关,PTEN阳性表达缺失与淋巴结转移有关(P<0.05),而Ki-67阳性表达与组织学分级、临床分期及淋巴结转移有关(P<0.01,P<0.05,P<0.01),与子宫肌层浸润程度无关.Rb2/P130、PTEN蛋白表达与Ki-67呈负相关(P<0.003.P<0.000).结论 Rb2/P130、PTEN蛋白与Ki-67的异常表达与子宫内膜癌的发生相关,有可能成为子宫内膜组织早期癌变的有用标记物.  相似文献   
59.
Summary The intermediate filament profile and the growth fraction of hepatocytes and bile duct epithelial cells were studied in a rat model of biliary fibrosis secondary to common bile duct ligation and scission. Strong vimentin expression was observed in epithelial cells of newly formed bile ductules, while normal liver contained only few weakly positive bile duct epithelial cells. All epithelial cells reacted with a pan-cytokeratin antibody. A monoclonal antibody specific for human cytokeratin 7 selectively reacted with both normal and newly formed bile duct epithelial cells. The intermediate filament profile of hepatocytes was constant, showing no changes during proliferation or in periportal areas adjacent to excessive bile duct formations. The proliferation-associated antigen detected by the antibody Ki-67 was present in many hepatocytes, homogeneously distributed in the lobules, but was seen only in a small proportion of the epithelial cells of the newly formed bile ducts. We conclude that vimentin may serve as an indicator for cellular reorganization in the bile duct system, and that the epithelial cells of newly formed bile ductules in this particular model of secondary biliary fibrosis were most likely to be derived from an outgrowth of the biliary duct system and recruitment of preductular epithelial cells. No morphological or immunohistological evidence suggesting a derivation from hepatocytes by ductular metaplasia or from oval cells was obtained.  相似文献   
60.
The overexpression of p53 protein and the Ki67 proliferative index was evaluated in 96 hepatocellular carcinomas (HCC), 67 in cirrhotic livers and 29 in non-cirrhotic ones, and in 13 non-carcinomatous lesions, all surgically resected from Italian patients. Overexpression of p53 was detected only in carcinomatous lesions, and was significantly related to the grade of HCC ( P < 0.001). In fact, p53 was observed in 7/7 (100%) cases of grade IV, 13/43 (30.3%) of grade III, and 10/ 46 (21.7%) of grade II. The relationship between p53 and Ki67 scores was determined in serial sections from corresponding areas of both diffuse and patchy immunoreactivity. In the overall population, p53-positive tumors showed a significantly higher Ki67 score (15.9 ± 5.5% vs 9.2 ± 4.3% [ P < 0.001]). This observation was evident in all grades of HCC.  相似文献   
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