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51.
Angiographic findings in seventy cases of maxillofacial hemangioma are reported. The tumors have been divided into four types: (1) plexiform hemangioma, (2) cavernous hemangioma with venous drainage, (3) cavernous hemangioma without venous drainage, and (4) the so-called "diffuse type" of cavernous hemangioma. The angiographic features of the four types are described, and clinical application is evaluated. The angiograms demonstrate the location, extent, blood supply, and drainage of the tumors and show whether they communicate intracranially, thus providing valuable criteria for planning and determining the mode of treatment.  相似文献   
52.
本研究通过根尖渗漏试验和可见光分光光度法比较热侧压充填法和传统侧压充填法的根尖封闭能力。结果表明:加用封闭剂热侧压充填法的根尖封闭能力最佳,优于单纯热侧压充填法(P<0.05)及传统侧压充填法(P<0.01)。但由于国产牙胶尖易粘至热充填器上带出,操作不便,目前推广应用热侧压法尚有困难。  相似文献   
53.
Originally found in stomach mucosa, ghrelin is a peptide appetite hormone that has been implicated as an immuno-modulatory factor. Ghrelin has also been found in salivary glands and saliva; however, its expression patterns and biological properties in the oral cavity remain unclear. Therefore, we investigated the expression patterns of ghrelin in saliva, gingival crevicular fluid (GCF), and gingival tissue, as well as its in vitro effects on IL-8 production by TNF-α or LPS-stimulated oral epithelial cells. In the clinical samples obtained from 12 healthy volunteers, the concentration of ghrelin in GCF remarkably exceeded that detected in saliva. The expression of ghrelin mRNAs and growth hormone secretagogue (GHS) receptors could be detected in human oral epithelial cells. Immunohistochemical analysis revealed the expression of ghrelin in gingival epithelium, as well as in fibroblasts in the lamina propria. Ghrelin increased intracellular calcium mobilization and cAMP levels in oral epithelial cells, suggesting that ghrelin acts on epithelial cells to induce cell signaling. Furthermore, synthetic ghrelin inhibited the production of IL-8 from TNF-α or LPS-stimulated oral epithelial cells. These results indicate that ghrelin produced in the oral cavity appears to play a regulatory role in innate immune responses to inflammatory infection.  相似文献   
54.
Parry-Romberg syndrome or progressive facial hemiatrophy is a rare clinical entity of an unknown etiology. We present the case of a 57-year-old Chinese woman with Parry-Romberg syndrome and hemifacial spasm both on the right side. Its association was not reported before. In our report of Parry-Romberg syndrome with hemifacial spasm, we try to explore whether there were some relations between the 2 diseases. We found an offending vessel compressing the root exit zone of the facial nerve and no evidence of vessel compression at ipsilateral trigeminal nerve motor rootlet.  相似文献   
55.
目的:采用Noordhoff法修复单侧不完全性唇裂,分析与常规方法的不同设计,提出在手术过程中应注意的问题。方法:通过对随机选择用Noordhoff法修复52例单侧不完全性唇裂的患儿的手术效果分析,提出Noordhoff法修复单侧不完全性唇裂手术方法的特点,阐明手术设计的思想和操作中应注意的问题。结果:52例中除其中1例因切口摔倒而裂开重新缝合外,余51例切口均I期愈合。所有患儿术后鼻、唇弓及红唇形态近期效果满意。结论:Noordhoff法手术方法的设计最大限度的利用了唇的软组织,避免了鼻翼外侧的切口,鼻唇畸形同期整复使单侧不完全性唇裂能达到较满意的效果。  相似文献   
56.
目的:研究狗乳牙正畸移动后其恒牙胚才周组织中集落刺激因子(CSF-1)及转化生长因子-β1(TGF-β1)的表达.探讨乳牙移动后其恒牙胚改变的机制。方法:取狗下颌第二乳磨牙正畸移动后14d的组织标本,用免疫组织化学染色技术观察TGF-β1和CSF-1在恒牙胚牙囊、牙周才槽骨组织中的表达。结果:TGF-β1和CSF-1的染色在乳磨牙牙根的远中牙周膜和牙槽骨中以及恒牙胚的远中牙囊和牙槽骨中的表达明显减弱,在乳磨牙牙根的近中牙周膜和牙槽骨中以及恒牙胚的近中牙囊和牙槽骨中的表达明显增强。结论:狗乳牙正畸移动后其恒牙胚牙周组织也发生骨改建。  相似文献   
57.
China is geographically located in the east of Asia and its population exceeds 1.3 billion. An understanding of dental education in China is thus of interest. However, as there is little published information on this topic, this paper provides information about China regarding its dental history, dental school system including curriculum and dental licensure. High school graduates take a nationwide entrance examination to apply for dental school, of which there are more than 50 in China. A five year dental education leads to the BDS degree. Dental school graduates must then pass the nationwide licensure examination to practise dentistry. Currently, there are not adequate numbers of dentists to provide the necessary oral health care for people living outside metropolitan areas.  相似文献   
58.
In the following respects, tooth enamel is a unique tissue in the mammalian body: (a) it is the most mineralized and hardest tissue in it comprising up to 95 wt% of apatite; (b) its microstructure is dominated by parallel rods composed of bundles of 40–60 nm wide apatite crystals with aspect ratios reaching up to 1:10,000 and (c) not only does the protein matrix that gives rise to enamel guides the crystal growth, but it also conducts its own degradation and removal in parallel. Hence, when mimicking the process of amelogenesis in vitro, crystal growth has to be coupled to proteolytic digestion of the amelogenin assemblies that are known to play a pivotal role in conducting the proper crystal growth. Experimental settings based on controlled and programmable titration of amelogenin sols digested by means of MMP-20 with buffered calcium and phosphate solutions were employed to imitate the formation of elongated, plate-shaped crystals. Whilst amelogenin can act as a promoter of nucleation and crystal growth alone, in this study we show that proteolysis exerts an additional nucleation- and growth-promoting effect. Hydrolysis of full-length amelogenin by MMP-20 decreases the critical time needed for the protein and peptides to adhere and to cover the substrate. The formation and immobilization of a protein layer subsequently reduces the time for calcium phosphate crystallization. Coupling the proteolytic reaction to titration in the presence of 0.4 mg/ml rH174 has been shown to have the same effect on the crystal growth promotion as quadrupling the concentration of rH174 to 1.6 mg/ml. Controlling the rate and the extent of the proteolytic cleavage can thus be used to control the nucleation and growth rates in a protein-guided crystallization system.  相似文献   
59.
60.
目的 探讨姜黄素对口腔舌癌细胞增殖与转移能力的作用及其作用机制.方法分别以0、5、10、20、30、60、100μmol·L-1姜黄素处理人舌癌细胞SCC-4 24 h,采用MTT法、侵袭实验、流式细胞仪、免疫荧光显微镜分别检测姜黄素对口腔舌癌细胞增殖与转移能力的影响.然后,采用cDNA微陈列芯片技术筛选和实时定鼍RT...  相似文献   
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