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101.
Relatively little is known about the formation of the acquired enamel pellicle other than that it involves the selective adsorption of specific proteins from oral fluids. Previous studies on the identification of pellicle components have relied largely on immunological or enzymatic detection and have been hampered by the fact that only minute quantities of pellicle can be removed from tooth surfaces. The present work describes an improved method of harvesting pellicle that combines mechanical and chemical removal; this approach was used to investigate systematically the desorption of in vitro pellicle components with different solutions. Eleven major in vitro pellicle proteins were identified by using a combination of electrophoretic separation and matrix-assisted laser desorption/ionization-reflectron time-of-flight mass spectrometry. A similar analysis of in vivo-formed pellicle revealed the presence of intact statherin, lysozyme, albumin and amylase. Further analysis of in vivo pellicle by liquid chromatography-electrospray ionization mass spectrometry suggested the presence of numerous low molecular-weight fragments of precursor proteins. The protein composition of in vitro whole-salivary pellicle adsorbed to hydroxyapatite and that of in vivo enamel pellicle differed for proline, the result of a reduction in the content of acidic proline-rich proteins in the in vivo samples. Unique features of the oral environment such as enzymatic activities or mineral surface properties may account for these differences between in vivo and in vitro pellicle formation.  相似文献   
102.
The use of a barrier membrane, with or without osseous allograft, has been shown to establish regeneration of osseous tissue around dental implants. Following three episodes of persistent symptomatic failed apicoectomy and subsequent tooth extraction, an osseointegrated implant was placed in a wide fenestrated defect. Demineralized freeze-dried bone allograft was covered by an occlusive expanded polytetrafluorethylene membrane. The reentry procedure revealed complete bone fill that followed the texture of the augmentation material beyond the previous buccal bony envelope.  相似文献   
103.
Tumor-infiltrating lymphocyte (TIL) in the primary site of oral SCC treated with S-PVP of PVP therapy was collected respectively and its yield,that is calculating the amount of TIL per tumor tissue.The cytotoxicity of TIL against the target,Tca8113 was detected.The results showed that the yield of TIL in S-PVP group was three times over that in PVP group.At the ratio of 5 to 1 (effector to target) the cytotoxicity was 38% in S-PVP group and 32% in PVP group.There was no significant difference in its cytotoxicity between two groups.The results revealed that immunochemotherapy of S-PVP regimen for treating oral SCC had neither direct damage to tumor cell from the agents nor antitumor immune reactivity with BRM stimulating an increasing in numbers of TIL.  相似文献   
104.
MRI在口腔颌面部肿块诊断中的应用   总被引:1,自引:0,他引:1  
作者对38例发生在口腔颌面部肿块患者采用MRI检诊。结合缅针穿吸缅胞学检查,并与CT扫描对比研究。结果提示:对口腔颌面部肿块。管状瘤或临床怀疑肿瘤有颅底、眶尖、翼腭窝、咽侧、颈部大血管神经累及者。MRI扫描成像清晰。软组织分辨率高。能早期发现骨质侵蚀。作者还对MRI在监测颌面部癌瘤切除术后局部是否复发进行初步观察。  相似文献   
105.
This article describes the treatment of a patient with periodontally "hopeless" teeth by conservative periodontal therapy combined with subgingival chlorhexidine irrigation and orthodontic tooth movement. The 3-year follow-up post-treatment shows the relative success of the treatment, without the use of surgical modality or the extraction of any teeth.  相似文献   
106.
介绍具有多功能、多通道及多参数测试特点的微机化力测试仪的研制方法,并用其进行了无牙颌患者戴全口义齿后咀嚼不同食物时的咀嚼力测试研究。测试表明,仪器性能稳定,灵敏度高,重复性好,数据可靠,测试结果满意  相似文献   
107.
108.
An increase in nitric oxide production has been demonstrated in periodontitis. Here we investigated the potential role of nitric-oxide-derived nitrating species (such as peroxynitrite) in a rat model of ligature-induced periodontitis. Formation of 3-nitrotyrosine, the stable product formed from tyrosine reacting with nitric-oxide-derived nitrating species, was detected in the gingivomucosal tissue. 3-Nitrotyrosine immunohistochemical analysis revealed a significant elevation in the number of immunopositive leukocytes, and higher immunoreactivity of the gingival ligaments and epithelium in the ligated than in the contralateral (control) side. On both sides, several 3-nitrotyrosine-positive bands and, on the ligated side, a unique 52-kDa 3-nitrotyrosine-positive band were detected by Western blot. However, in the sterile gingivomucosal tissue of rat pups, no 3-nitrotyrosine or inducible nitric oxide synthase immunoreactivity was found. Analysis of these data suggests that resident bacteria of the gingivomucosal tissue induce an increase in reactive nitrogen species, which is greatly enhanced by plaque formation in periodontitis.  相似文献   
109.
110.
To quantitatively evaluate the acoustic characteristics of glottal stop, pronunciation of/ka/in 10 normal subjects and 14 patients with cleft palates were analyzed by sound spectrography and 20 msec in all normal articulation of /ka/ with an average time of 44.6 msec.In the test group of /ka/ demonstrated an average time of 20.8 msec.The inverse correlation ship between VOT and the psyco-acoustical judgment for the degree of distortion was demonstrated to be significant.  相似文献   
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