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991.
目的比较不同抛光方法对烤瓷表面粗糙度的影响,以及不同粗糙度烤瓷表面对口腔变异链球菌黏附的影响。方法采用原子力显微镜测量不同抛光方法对瓷表面粗糙度的影响,并通过细菌实验观察不同粗糙度的瓷表面对细菌黏附的影响。结果用抛光膏抛光或者上釉后,瓷面平整且有光泽。无论是表面粗糙度还是表面黏附的细菌数,橡皮轮组都大于抛光膏组和上釉组(P<0.05)。结论建议调改过的瓷表面进行抛光膏抛光或上釉以恢复瓷表面的光滑度和减少口腔致龋菌的黏附。  相似文献   
992.
目的系统评价牙周基础治疗对2型糖尿病相关性牙周炎患者血糖控制的影响,探讨牙周基础治疗在糖尿病治疗中的具体作用。方法计算机检索Cochrane图书馆对照试验注册中心、Medline、EMbase、SIGLE、GreyNet、NTIS、中国生物医学文献数据库、中文科技期刊全文数据库、中国期刊全文数据库和万方数据库,查找有关牙周基础治疗对糖尿病血糖控制影响的研究。检索时限均为1991-2011年4月31日。均由2名评价者独立选择试验、提取资料和评估方法学质量,然后采用RevMan 5.1软件对资料进行Meta分析。纳入7个研究,共计471例受试患者。结果牙周基础治疗能明显降低2型糖尿病相关性牙周炎患者糖化血红蛋白的水平,组间差异有统计学意义(95%CI:-0.94—0.22,P=0.001)。治疗组牙周袋探诊深度低于对照组,组间差异也有统计学意义(95%CI:-2.26~0.69,P=0.0002)。结论牙周基础治疗有利于2型糖尿病相关性牙周炎患者总体血糖水平的控制。  相似文献   
993.
目的:研究全口义齿排牙后牙不同倾斜角度对义齿稳定性的影响。方法:随机抽取临床模型,参照丸森贤二的分类法分别采用Monson型排牙法、anti-Monson型排牙法及flat型排牙法[5]进行后牙区排牙,以1cm厚的橡胶垫在患者口内做咀嚼测试并进行分析。结果:上颌义齿后牙的排牙角度始终是Monson型排牙法最稳定,flat型排牙法和anti-Monson型排牙法不稳定;下颌义齿后牙的排牙角度应根据牙槽嵴的形态选择不同的排牙法;结论:全口义齿后牙区排牙时,倾斜角度不同对义齿固位与稳定有重要影响。  相似文献   
994.
义齿树脂基托是全口义齿及局部义齿的重要组成部分,由于其具有吸水性和溶解性,加之释放一些残留单体,影响了材料的综合性能,降低了材料的使用寿命,并给患者的健康造成一定的危害。本文就义齿树脂基托的吸水性和溶解性机制及相关问题做一综述。  相似文献   
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The prevalence of congenital anomalies of the coronary arteries (CAAs) is reported to be approximately 0.2-1.4% of the general population. Of them, The double right coronary artery (RCA) is one of the rarest coronary anomalies. Nonetheless, there is no consensus of the definition of a double RCA until now. Several concepts have been proposed in order to define what is and is not a double RCA. So far, it was been reported 37 times and in 44 cases after a comprehensive literature search through the PubMed database, using the keywords “double right coronary artery,” “duplicated right coronary artery,” “dual right coronary artery” and “split right coronary artery.” Most of the published articles (28 of 37 articles) used the name “double right coronary artery.” Nevertheless, some investigators contended that a split RCA is anatomically the same anomaly as the improperly named “double right coronary artery”. The debate between those who favor “double RCA” and those who favor “split RCA” indicate the need for a consensus regarding the nomenclature as well diagnostic criteria of such coronary anomalies. It is the time we need to reach a consensus of the nomenclature of this congenital coronary anomaly.  相似文献   
999.
Besides the MHC gene, HLA-B27, ERAP1 is one of the non-MHC genes which also play key roles in the pathogenesis of AS. It has been reported that there is an association between ERAP1 polymorphisms and AS Risk. However, the results were inconclusive. The aim of the current study was to determine the contribution of ERAP1 polymorphisms to ankylosing spondylitis (AS) susceptibility. To derive a more precise estimation of the association, a meta-analysis was performed by searching the MEDLINE and EMBASE data base. The crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to access the strength of association between ERAP1 polymorphisms and AS risk. The pooled ORs were performed for minor allele versus major allele in all polymorphisms. Nine case–control studies consisting of 8,530 AS patients and 12,449 controls were identified in this meta-analysis. Except in rs27434 (P = 0.23), the significant correlation between ERAP1 polymorphisms and AS susceptibility has been detected in rs27044 (OR 1.57, P < 0.001), rs17482078 (OR 1.271, P < 0.001), rs10050860 (OR 0.772, P = 0.006), rs30187 (OR 1.348, P < 0.001), rs2287987 (OR 0.746, P < 0.001) and rs27037 (OR 1.257, P = 0.001). This meta-analysis demonstrates that the ERAP1 polymorphisms may play a significant role in susceptibility to AS. However, this result should be identified by more convincing experimental evidences in molecular level and population level.  相似文献   
1000.
Background/Aims: Abnormalities in cell cycle regulation are reported to be strongly associated with tumorigenesis and progression of tumors. Wnt/β-catenin signaling pathway and cell cycle play key roles during the genesis and development of hepatocellular carcinoma (HCC). Current studies indicated that expressions of cyclin A, E and D1 were affected after silencing of β-catenin gene in HCC, but it is unclear if other cyclins are affected. Methodology: To determine the relation, small interference RNA (siRNA) against β-catenin was transfected into HCC cell lines HepG2 and SMMC-7721, and cell cycle and cyclin B1 and cyclin C protein expression were detected. Results: Cell cycle was arrested in G0/G1 at 72h after transfection and the cell cycle began to transfer from G0/G1 to G2/M through S and had a trend to revert at 96h. In addition, β-catenin protein expression was decreased at both 72 and 96h, although the level was slightly higher at 96h than that at 72h. However, cyclin B1 expression decreased at 72h and increased at 96h, cyclin C expression increased at 72h and decreased at 96h. Conclusions: These findings suggest that silencing β-catenin gene may induce the changes of cell cycle and cyclin B1 and cyclin C protein expression. Wnt/β-catenin signaling pathway probably takes part in the genesis and development of HCC through regulating cell cycle and the expression of cyclin B1 and cyclin C.  相似文献   
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