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91.
口腔鳞状细胞癌与人乳头状瘤病毒感染的关系   总被引:1,自引:0,他引:1  
本文用抗牛乳头状瘤病毒(BPV)的抗血清对31例口腔鳞状细胞癌中的人乳头状瘤病毒(HPV)结构抗原进行检测,证明其中30例口腔鳞状细胞癌中HPV结构抗原一,说明口腔癌的发病与HPV感染有密切关系,对防治HPV感染,减少口腔癌的发病有着重要意义。  相似文献   
92.
Aim  To investigate the in situ location of oncostatin M (OSM) in epithelialized apical periodontitis lesions.
Methodology  Thirty periapical lesions of pulpal origin were collected with informed consent from patients at the time of apical surgery. Tissue specimens were fixed with 10% buffered formalin overnight, dehydrated in an ascending series of graded alcohol, and embedded in paraffin. Five micron sections from formalin-fixed, paraffin-embedded specimens were examined by immunohistochemistry. In addition, another section from each specimen was stained with haematoxylin and eosin to assess the presence of inflammatory infiltrates. Differences in OSM expression between tissue with low and high levels of inflammation were subsequently analyzed by Fisher's exact test.
Results  Based on histological examination of haematoxylin and eosin stained sections, all specimens revealed the morphology of epithelialized apical periodontitis lesions. The results from immunohistochemistry demonstrated that OSM stain was detected in the inflammatory infiltrates, epithelium, connective tissue, and endothelium. The OSM signal was mainly expressed in endothelial cells (100%) followed by inflammatory cells (93.33%), epithelial cells (53.33%), and fibroblasts (16.67%). In addition, OSM expression was significantly higher in epithelialized apical periodontitis with higher levels of inflammatory infiltrates ( P  < 0.001).
Conclusions  Oncostatin M was found to be expressed in epithelialized apical periodontitis lesions and would form part of the cytokine network involved in the disease process of apical periodontitis.  相似文献   
93.
BACKGROUND: Human beta-defensins (hBDs) are antimicrobial peptides which contribute to host innate immunity by disrupting the membrane integrity of a broad spectrum of microorganisms. OBJECTIVES: This study aimed to determine the expression profiles of hBD-1 and -2 peptides in gingiva and to assess the possible relations of these antimicrobial peptides with periodontal health and disease. METHODS: Seven periodontally healthy subjects and 22 patients with unresolved chronic periodontitis were recruited and the gingival biopsies collected consisted of healthy tissues from the healthy subjects (HT-C); periodontal pocket tissues (PoT) and inflamed connective tissues (ICT) from the base of pocket, i.e. granulation tissues, as well as clinically healthy tissues (HT-P) from the adjacent clinically healthy sites from the patients. The expression of hBD-1 and -2 peptides was detected by immunohistochemistry and quantitatively analyzed with a computerized image processing system. RESULTS: Both hBD-1 and -2 peptides were detected in all periodontally healthy subjects, while hBD-1 was detected in all patients and hBD-2 was found in most of the patients. Their expression was mainly confined to the granular and spinous layers of gingival epithelium, in which hBD-1 was detected in both intercellular spaces and cytoplasm, whereas hBD-2 was mainly observed in the cytoplasm. HT-C expressed significantly higher levels of hBD-2 than HT-P (p < 0.05). Within the patients, both defensins were up-regulated significantly in PoT as compared with the adjacent HT-P (p < 0.05). CONCLUSIONS: The present study showed that hBD-1 and -2 were frequently expressed in the granular and spinous layers of gingival epithelia and their expression may be associated with periodontal health and disease.  相似文献   
94.
目的 研究口腔鳞状细胞癌(OSCC)组织中细胞周期素D1(Cyclin D1)的表达及意义.方法 应用免疫组织化学Envosion法检测50例OSCC患者与10例正常黏膜组织中Cyelin D1蛋白在病理组织切片中的表达水平,并进行统计学分析.结果 在50例OSCC标本中Cyclin D1主要表达在细胞核,也有少量表达...  相似文献   
95.
Oral Diseases (2011) 17 , 808–812 Objective: The aim of this study was to determine the expression of fatty acid synthase (FASN) in oral nevi and melanomas, comparing the results with correspondent cutaneous lesions. Materials and Methods: Expression of FASN was evaluated by immunohistochemistry in 51 oral melanocytic lesions, including 38 intramucosal nevi and 13 primary oral melanomas, in 10 cutaneous nevi and in 14 melanomas. Results: Fatty acid synthase was strongly expressed only in melanomas, either of the oral mucosa or cutaneous. On the other hand, most oral and cutaneous nevi were negative, with a few oral cases showing focal and weak expression. Conclusion: Fatty acid synthase is expressed in malignant melanocytes, and it can be a helpful marker to distinguish oral melanomas from oral melanocytic nevi.  相似文献   
96.
Cytokeratin (CK) is a filament which plays a central role in epithelial tissue and, like the polypeptides of intermediate filaments in general, shows a high degree of tissue specificity. The CK expression patterns of odontogenic epithelia are still poorly described. We studied the distribution of individual CK polypeptides in the human enamel organ at bell stage and in remnants of the dental lamina. Our immunohistochemical study showed that epithelial cells stained for CKs 7, 13, 14 and 19 with slight changes in their pattern during the differentiation phase of odontogenesis. There was negative staining for all other CK polypeptides tested (CKs 8, 10, 16, 17 and 18). Most of the CKs in the enamel organ epithelia did not show differences related to the stage-specific state of differentiation, except for CKs 14 and 19 at the inner enamel epithelium. A strong label for CK 14 was present at the inner dental epithelium at early bell stage, and this was substituted by CK 19 at the late bell stage when the ameloblasts were fully differentiated.  相似文献   
97.
In view of the different terminology for salivary gland tumours with giant cells, eleven cases were analysed by histopathology and immunocytochemistry. Four cases (three pleomorphic adenomas, one carcinosarcoma in a pleomorphic adenoma) were classified as having a foreign-body giant cell reaction, and five cases (two mucoepidermoid carcinomas, one acinic cell carcinoma, two carcinomas in pleomorphic adenomas) as having a sarcomatoid osteoclast-like giant cell reaction. In two further cases a giant cell tumour and a giant cell granuloma were associated with carcinomas in pleomorphic adenomas. All giant cells showed characteristic expression of CD68 as a typical marker for histiocytes and macrophages with their origin in mononuclear haematopoetic stem cells. There was no evidence for an epithelial origin of the giant cells because all those examined had a negative reaction to cytokeratin. Foreign-body cells were characterized by cytoplasmic vacuoles and irregularly dispersed nuclei. They showed a focally circumscribed reaction mostly outside the connective tissue pseudocapsule of the tumours. The sarcomatoid osteoclast-like giant cell reactions in carcinomas were distinctly intermingled with the carcinomatous patterns. In contrast, the associated osteoclast-like giant cell tumour was distinctly separate from the salivary gland tumour tissue and was composed of numerous larger osteoclast-like giant cells with a greater number of nuclei (more than 20): these giant cells were uniformly distributed throughout the tumour tissue. The giant cell granuloma was also separate from the carcinoma and was composed of nests of smaller, more irregularly distributed giant cells.  相似文献   
98.
目的 了解正常口腔黏膜,癌前病变及癌组织中内皮素I(ET-I)表达特点及其变化规律。方法采用免疫组化和图象分析技术,对人正常口腔黏膜(NOR)10例、口腔黏膜下纤维化(OSF)10例、鳞状细胞癌(SCC)15例上皮细胞的ET-I含量进行图像分析。结果 ①ET-I在OSF、OLK、SCC组织中的表达增强,阳性物质主要位于上皮棘细胞、基质细胞的胞浆胞膜上,且ET-I含量显著高于正常对照组(p<0.01)。②OLK、SCC上皮细胞ET-I含量呈显著增加趋势(p<0.05)。③OSF上皮细胞ET-I含量显著高于OLK(p<0.05),与SCC相比无显著性差异(p>0.05)。结论 ET-I含量在口腔癌前病变至癌变过程中可能存在一种量变关系,OSF中ET-I过量表达可能提示其上皮细胞的癌变潜能。  相似文献   
99.
人牙髓组织缺氧耐受机制的初步研究   总被引:1,自引:0,他引:1  
目的:研究缺氧诱导因子-1α(Hypoxia inducible factor-1α,HIF-1α)和环氧化酶-2(Cyclooxygenase-2,COX-2)在人正常牙髓和炎症牙髓中的免疫定位,探讨缺氧耐受机制在牙髓炎病程中和牙髓自身修复过程中的作用和意义。方法:通过SP法对第1组10例健康牙髓、第2组10例深龋(有过敏症状但无牙髓炎症状)患牙牙髓、第3组15例急性牙髓炎牙髓和第4组15例慢性牙髓炎牙髓进行免疫组化染色,分别对HIF-1α和COX-2进行免疫定位和半定量分析。结果:①HlF-1α在第1组健康牙髓和第2组深龋牙髓标本中,只有个别标本呈弱阳性表达,二组问无显著性差异(P〉0.05),但对比其它二组标本则有显著性差异(P〈0.001):第3组急性牙髓炎牙髓呈强阳性表达,第四组慢性牙髓炎牙髓亦呈阳性染色与第3组比较总体偏弱,有显著性差异(P〈0.05)。②COX-2在第1组牙髓中个别标本呈弱阳性表达;第2组标本绝大多数染色呈弱阳性,与第1组比较有显著性差异(P〈0.05);第3组标本染色均呈强阳性,与前两组比较有显著差异性伊值分别为P〈0.001,P〈0.05);第4组标本亦呈阳性染色,总体上阳性程度明显高于第l组(P〈0.001),高于第2组(P〈0.05),弱于第3组(P〈0.05)。HIF-1α与COX-2的表达关系主要在第3组和第4组牙髓标本中体现明显,在第3组二者的变化大致呈平行关系;在第4组基本呈反向变化关系。结论:HIF-1α和COX-2在牙髓炎病程中可能发挥着重要的生理和病理作用,在牙髓炎进程中和牙髓自身修复过程中可能存在着缺氧环境和缺氧耐受机制。  相似文献   
100.
目的:通过比较CBFa1/Osf2和BMPs在牙周组织中的表达及变化,探讨在正畸骨改建过程中,这两个对骨形成起到重要作用的因子之间的相互关系,为进一步深入研究正畸牙移动的生物学机制奠定基础。方法:建立大鼠正畸牙移动的动物模型,并采用免疫组织化学的方法检测CBFa1/Osf2和BMPs在此过程中的表达。结果:正畸牙移动过程中CBFa1/Osf2和BMPs在牙周组织的分布及表达变化的时间上具有明显的一致性;均表现为实验组表达明显强于对照组,张力侧表达强于压力侧;其中成骨细胞、成纤维细胞及破骨细胞均为强表达。结论:CBFa1/Osf2和BMPs均参与了正畸的骨改建过程,且可能在正畸骨改建中起到重要作用。  相似文献   
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