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61.
The degradation of the basement membrane by matrix-metalloproteinase(MMP) and serine protease is a critical pointin tumor invasion and metastasis. We measured theactivity of MMP-9 from 28 normal, 12 benignand 126 breast cancer tissues using gelatin zymographywith an image analysis system. ProMMP-9 was expressedin 17.5% of the cancer patients compared to2.5% in 40 non-cancerous tissues (p=0.014).The mature form of MMP-9 (82 kD) wasexpressed only in T2–T4 stages. During the earlyphase of breast cancer (DCIS and T1 stage)progression, only production of proMMP-9 increased. However, asthe cancer grew or invaded skin (T2–T4), orwith lymphovascular permeation, both production and activation ofMMP-9 increased. In conclusion, proMMP-9 production was themain cause of increased MMP-9 activity during theearly phase, while both production and activation increasedin the late phase of breast cancer.  相似文献   
62.
大鼠脑神经干细胞神经巢蛋白表达的流式细胞术检测   总被引:9,自引:1,他引:8  
检测胎鼠及成年大鼠脑内神经干细胞特异性抗原神经巢蛋白的表达,判明啮齿类哺乳动物脑内神经干细胞存在的可能性及相应的部位。方法:显微手术下采取胎鼠及成年大鼠大脑与皮质下脑组织,间接荧光法标记nestin,以流式细胞术检测。结果胎鼠脑内普遍存在nestin阳性细胞,成年大鼠脑室旁组织中也存在nestin阳性细胞。  相似文献   
63.
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.  相似文献   
64.
孙刚  王竫华 《眼科新进展》2004,24(2):150-152
青光眼性损伤的形态学特征及病理机制 ,在视网膜节细胞水平及视神经水平已得到广泛研究 ;最近研究表明 ,青光眼对外侧膝状体、视皮质等中枢视路也存在相应损伤 ,并且提示青光眼的中枢损伤可能参与视功能状态的进一步恶化。我们对近年来青光眼中枢损伤的病理形态学及病理机制研究作一综述。  相似文献   
65.
目的 探讨膜型基质金属蛋白酶 - 1(membranetype - 1matrixmetalloproteinase,MT1-MMP)在卵巢上皮癌组织中的表达及其与肿瘤生物学行为和预后的关系。方法 用免疫组化SP法检测 5 6例卵巢上皮癌组织、 15例卵巢良性肿瘤组织以及 10例正常卵巢组织中MT1-MMP蛋白的表达。结果  6 7 9%的卵巢上皮癌组织MT1-MMP表达阳性 ,卵巢良性肿瘤组织很少表达 (4/ 15 ) ,正常卵巢组织中几乎不表达 (1/ 10 ) ,差异有显著性 (P <0 0 1)。MT1-MMP的表达水平与临床分期、组织学分级以及淋巴结转移密切相关。在单因素生存分析中 ,MT1-MMP的表达与患者预后不良有关。但是 ,在多因素分析中 ,MT1-MMP的表达并不是一个相对独立的预后因素。结论 ①MT1-MMP在卵巢上皮癌中异常高表达 ;②MT1-MMP表达促进卵巢癌的侵袭和转移 ,可作为判断卵巢癌恶性表型的有用指标 ;③MT1-MMP的阳性表达与患者不良预后有关。  相似文献   
66.
Apart from clinical stage and lymph node status, acknowledged to be among the most powerful predictors of outcome in cervical cancer, the determination of prognosis and thereby the need for adjuvant therapy in surgically treated patients currently relies on a variety of histopathologic factors. The role of many of these is controversial. This may be because histopathology is genuinely lacking in sensitivity for predicting tumor behavior in vivo. There is, however, wide variation in histopathologic definitions and criteria. This is probably the major reason for both the lack of reproducibility in the reporting of certain factors and in their diminished value in predicting behavior. Tumor type, grade, vascular invasion, pattern of invasion, and depth are all extremely important prognostic indicators when used individually or as a part of a scoring system.  相似文献   
67.
This article reviews a few key ideas about the representation of information in neural networks and uses these ideas to address one aspect of autism, namely, the apparent hyperspecificity that is often seen in autistic children's application of previously acquired information. Hyperspecificity is seen as reflecting a possible feature of the neural codes used to represent concepts in the autistic brain.  相似文献   
68.
Previous studies with single-unit recording and 2-[14C]deoxyglucose quantitative autoradiography have shown that systemic administration of apomorphine increases the functional activity of pallidal neurons, and that the enhancement in the globus pallidus (GP) activity is abolished by striatal lesions. The present study employing electrophysiological techniques tested whether embryonic striatal tissue implanted in the excitotoxically damaged striatum of rats may affect the lesion-induced alteration in the neuronal response of GP to apomorphine. Systemically administered apomorphine significantly increased spontaneously firing rates of GP cells. The blockade of dopamine receptors with haloperidol reversed the increased rate to baseline levels. Quinolinate-induced striatal lesions attenuated the rate-increasing effect of apomorphine. Embryonic striatal grafts placed in the lesioned striatum restored the response of GP cells to systemic apomorphine. The graft-mediated restoration of the GP neuron response to apomorphine were accompanied by an improvement in the motor asymmetry induced by this drug. Considering previous anatomical data to demonstrate extensive innervation of the GP by embryonic striatal grafts, the present results suggest that the grafts reconstruct the functional striatopallidal pathway which is capable of transmitting apomorphine-induced changes in the neuronal activity.  相似文献   
69.
Prognostic factors in maxillary sinus and nasal cavity carcinoma   总被引:2,自引:0,他引:2  
AIMS: The aim of the present study is to define prognostic factors, particularly the impact of treatment on paranasal sinus and nasal cavity malignancies. MATERIAL AND METHODS: Retrospective study of patients with maxillary antrum and nasal fossae malignancies. A maxillectomy classification as performed to treat malignancies in our institution is described. Multivariate analysis of prognostic factors was done using the Cox's model. RESULTS: One hundred and nine patients were evaluated. Squamous cell carcinoma was found in 62 cases and in 95 patients the epicentre of the tumour was located in the maxillary antrum. Ten patients were treated with surgery only, 39 patients with surgery and adjuvant radiation therapy, 37 cases received only radiotherapy, and 18 received radiotherapy followed by surgery; in five cases a combination of chemo-radiotherapy was used. Multivariate analysis identified T classification, orbit invasion, N classification, site of origin of tumour in nasal fossae, and no surgical resection as independent prognostic factors (p=0.0001). CONCLUSION: T4 tumours with orbit invasion present bad prognosis as compared to other T4 tumours. Surgical resection should be included in the treatment strategy. Because of the high frequency of lymph-node metastasis, neck treatment should be considered in T4 tumours.  相似文献   
70.
目的 探讨多参数 MRI 联合临床危险因素术前预测直肠癌淋巴血管间隙侵犯(LSVI)的价值。 方法 回顾性分析池州市人民医院 2022 年 4 月至 2023 年 11 月经术后病理证实的 38 例直肠癌患者的临床及影像学资料,所有患者均行常规 MRI、合成 MRI及 IVIM-DWI 序列扫描。依据术后病理结果分为 LVSI 阳性组(n=14)和 LVSI 阴性组(n=24)。采用单因素和多因素 logistic 回归分析LVSI 阳性组和 LVSI 阴性组的临床资料,分析 LVSI 的临床危险因素;比较两组患者合成 MRI (T1 值、T2 值、PD 值)及 IVIM-DWI 参数(D值、D*值、f 值),采用受试者工作特征(ROC)曲线评价各定量参数预测模型及联合临床危险因素预测模型的诊断效能。 结果 合成MRI 的 T2 值及 IVIM-DWI 的 D 值、f 值在直肠癌 LVSI 阳性组和阴性组中比较差异具有统计学意义(P<0.05)。术前 CEA(OR=10.818,95%CI:1.391~84.124)及临床 N 分期(OR=11.852,95%CI:1.534~91.552)是直肠癌 LVSI 的独立危险因素(P<0.05)。单独的 T2 值、D 值、f 值及三者联合的曲线下面积(AUC)分别为 0.801、0.747、0.766、0.807,联合临床危险因素的预测模型效能最高(AUC=0.845),灵敏度为 78.58%,特异度为 100%。 结论 多参数 MRI 术前可有效预测直肠癌 LVSI 的状态,结合临床危险因素的联合预测模型可进一步提升预测效能,有助于临床医师制定个性化直肠癌治疗方案。  相似文献   
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