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31.
32.
近年来人们对干眼症的关注与日俱增,中医药发挥其传统优势,运用内治,外治,针灸等方法,达到机体脏腑功能平衡,气血津液充足,化生泪液有源,泪液不乏。但是,目前中医学对于干眼症的研究还存在一些问题。第一,干眼的疗效评价标准参照西医学标准,中医方面尚无统一标准。第二,干眼症的中医辨证分型也无统一标准,数据可信度难以保证。第三,临床的研究设计多为小样本,科研设计不够严谨,缺乏相关的动物实验研究。干眼症是多种原因诱发的疾病,已经逐步引起人们的重视,但就其发病的病因及机制应更进一步的深入研究。治疗上应在中医整体观念的指导下,运用辨证施治同时结合现代医学理论。应统一干眼症的辨证分型及疗效评价标准,增加临床观察指标的客观性及可信度,同时临床学者及科研工作者应尝试采取大样本,多中心的随机对照实验,让研究结果更有说服力,也应该尝试更多的动物实验研究,运用先进的科学技术及方法研究本病的病理生理状况,预防等,将其结果转化为临床可用的知识,为干眼症的诊疗开辟新的篇章。 相似文献
33.
Aim: The aim of this study was to evaluate the prognosis of subluxated, luxated and root fractured teeth in children treated by removable splints, designed to stabilize mobile anterior teeth and eliminate occlusal trauma due to malocclusion. Material and methods: A total of 227 traumatized anterior teeth (91 subluxated, 105 luxated and 31 root fractured teeth) treated with a removable splint were observed for 3 years. The traumatized teeth were from 79 children aged between 6–12 years (mean 8 years 5 months). If a traumatized tooth was extremely mobile, a fixed splint was first made before the impression was taken for the removable splint. Two weeks after completion of the removable splint treatment, an impression was taken again to evaluate the occlusal relationship of pre‐ versus post‐treatment of removable splint. Results: The treatment period with a removable splint averaged 3 weeks in subluxated teeth, 3–5 weeks in luxated teeth, 4–6 weeks in apical third root fracture injuries, and more than 5 weeks in middle third root fracture injuries. All the subluxated teeth and 74.1% of the luxated teeth maintained their pulp vitality during the 3‐year follow‐up period. Two of 21 (9.5%) apical third root fracture teeth and three of five (60%) middle third root fracture teeth had pulp necrosis in the coronal fragments. Internal resorption was not found in any of the traumatized teeth. External replacement resorption was not found in subluxated and luxated teeth. All the root fractured teeth displayed transient external resorption around the fracture lines. The surface resorption appeared to be self‐limiting and not to threaten the retention of the tooth. Inflammatory resorption was observed in teeth with pulp necrosis, but in all cases this was reversed with endodontic treatment. Eight of 23 (39%) apical third root fractured teeth displayed replacement resorption in their apical fragments, but the resorption was not serious enough to extract the tooth. No obvious alteration in the occlusal relationship was found comparing pre‐ and post‐treatment casts. The removable splints appeared to positively affect healing after traumatic injuries, as evidenced by the low number of complications at the 3‐year follow‐up period. 相似文献
34.
实时定量PCR检测氟对软骨细胞COLⅨA3基因表达的影响 总被引:1,自引:0,他引:1
目的:探讨氟对体外培养软骨细胞中COLⅨA3基因mRNA的表达影响。方法:采用SYBR GreenⅠ嵌合荧光法进行实时定量PCR的方法,检测不同剂量氟对体外培养软骨细胞中COLⅨA3基因mRNA的表达影响,染氟剂量分别为0、5、10、20、40mg/L,染氟10d。结果:实时定量PCR检测显示各组均可检测到COLⅨA3mRNA,相对定量比由对照组到高剂量组约为:100:134:200:104:129,染氟实验组中5mg/L、10mg/L组表达量高于对照组和40mg/L组,且以10mg/L组表达量最高,是对照组的2倍。随着染氟剂量增加,软骨细胞COLⅨA3基因mRNA表达量降低。结论:不同剂量氟对软骨细胞中COLⅨA3基因mRNA表达的影响不同,低剂量氟可以促进COLⅨA3基因mRNA的表达,随剂量增加氟的促进作用减弱。 相似文献
35.
目的 观察4种自酸蚀黏接系统对充填体在牙釉质和牙骨质处边缘密合性的影响。方法 36颗离体牙于颊、舌侧牙颈部预备Ⅴ类洞型,分别用4种自酸蚀黏接材料(Prime & Bond NT,SE-Bond,Adper^TM Prompt^TM,FL-Bond)处理后,充填4种牙体充填材料(Dyract AP、Cleanrfil AP-X、3MZ100、Beautifil),采用染料渗透和扫描电镜方法观察温度循环前后充填体在牙釉质和牙骨质处的密合性。结果 4种充填体在经温度循环后,牙釉质处的密合性都明显降低(P〈0.01);在牙骨质处,Dyract AP和Clearfil AP-X的密合性无明显变化(P〉0.05),3MZ100密合性明显提高(P〈0.01),而Beautifil的密合性明显降低(P〈0.05)。结论 4种自酸蚀黏接材料在牙釉质处的黏接强度有待进一步增强以获得良好的边缘密合性。 相似文献
36.
目的探讨直丝弓矫治技术对安氏Ⅱ类骨性错畸形患者骨面型的改变情况。方法在矫治前拍摄的头颅定位侧位片上,筛选出8例安氏Ⅱ类骨性错畸形患者,应用直丝弓矫治技术进行矫治,矫治结束后,在同样条件下再拍摄头颅定位侧位片,行头影测量分析,与治疗前数值进行比较,观察骨面型的改变情况。结果直丝弓矫治对安氏Ⅱ类骨性错畸形患者的面型略有改变,但患者的深覆及深覆盖的纠正更多是由下前牙唇侧倾斜来代偿完成。结论安氏Ⅱ类骨性错畸形患者在恒牙期早期或恒牙期直接采用直丝弓矫治技术进行矫治,对牙齿排列和咬合关系调整虽然有一定的治疗效果,但是对侧面型的改善程度有限,不能达到理想的矫治效果。 相似文献
37.
玻璃离子水门汀与银汞粘接的剪切力测试 总被引:2,自引:0,他引:2
探讨了玻璃离子水门汀增强银汞充填体与牙体之间的粘结作用。取新鲜离体人磨牙制成3mm厚的牙块,在其中央制备直径3mm的圆柱形洞,分别以玻璃离子、银汞粘结剂涂于洞壁,再充填银汞合金,另设空白对照组。两周后测各组的剪切力并作统计学分析。结果表明:玻璃离子与银汞粘结剂组的剪切力比空白对照组大,并有显著差异;说明玻璃离子与银汞粘结剂均有相似的增强银汞修复体与牙体之间粘结力的作用。 相似文献
38.
Lei Zhang Xiue Jiang 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,583(2):292-299
Gold nanoparticles have been attached on glassy carbon electrode surface through sulfhydryl-terminated monolayer and the gold nanoparticles-immobilized glassy carbon electrodes have been applied to the electrocatalytic oxidation of ascorbic acid, reducing the overpotential by about 200 mV with obviously increased current response. Due to its strong electrocatalytic activity towards ascorbic acid, the gold nanoparticles modified electrode can resolve the overlapped voltammetric waves of ascorbic acid and dopamine into two well-defined voltammetric peaks with peak-to-peak separation in potentials of about 300 mV. This can be used to allow the selective determination of ascorbic acid in the presence of dopamine. The catalytic current obtained from differential pulse voltammetry is linearly dependent on ascorbic acid concentration over the range of 6.5 × 10?6 to 1.45 × 10?4 M with correlation coefficient of 0.998 in the presence of dopamine. The detection limit (3σ) for AA was found to be 2.8 × 10?6 M. The simultaneous determination of ascorbic acid and dopamine in their binary mixture has also been investigated. The modified electrode shows good selectivity, stability and anti-fouling properties. The proposed methods have been used for the selective determination of ascorbic acid in the presence of dopamine and for the simultaneous determination of both them in their mixtures with satisfactory results. 相似文献
39.
目的:用新型组合式矫治装置治疗替牙期及恒牙初期安氏Ⅱ1错牙合。方法:采用由口外弓、下颌唇挡及上颌斜面导板组成的矫治装置,治疗替牙期及恒牙初期安氏Ⅱ1错牙合66例(男3 0例,女3 6例) ,治疗前后进行X线头影测量分析。结果:66例患者的覆牙合、覆盖及颌关系调整时间为3~13个月,平均7.6个月。治疗后覆牙合平均减小2 .5mm ,覆盖减小4.3mm ,SNB角增加1.8°,ANB角减小1.9°,U 1 NA角减小8.8°,L1 NB角增加6.4°,IMPA角增加5 .7°,Z角增加4.5°,Wits值减小1.6,ANS Me增加4.0mm。结论:该组合式矫治装置对替牙期及恒牙初期安氏Ⅱ1错牙合具有良好的矫治效果。 相似文献
40.
This clinical study evaluated the retention and caries protection of a flowable resin composite (Flow Line) and a flowable compomer (Dyract Flow) used in preventive resin restorations as compared to the conventional preventive resin technique which uses a resin composite (Brilliant) and a sealant (Concise). This study observed 205 permanent molars with small carious cavities less than 1.5 mm in width, which were obtained from 165 children aged 7 to 15 years. Flowable resin composite was used to treat 75 teeth, and 71 teeth were treated with flowable compomer in both cavities and caries-free fissures. For the control group, 59 teeth were treated with resin composite in cavities and sealant in caries-free fissures. The teeth were evaluated at 3, 6, 12, 18 and 24-month intervals. After three months, all 205 treated teeth were completely intact. After six months, 66 of the 71 teeth treated with flowable resin composite and 65 of the 70 teeth treated with flowable compomer were complete, compared to 57 of the 58 teeth treated with the conventional preventive resin technique. After 12 months, 60 of the 67 teeth treated with flowable resin composite and 61 of the 67 teeth treated with flowable compomer were complete, compared to 51 of the 55 teeth treated with the conventional preventive resin technique. After 18 months, 53 of the 61 teeth treated with flowable resin composite and 54 of the 62 teeth treated with flowable compomer were complete, compared to 47 of the 53 teeth treated with the conventional preventive resin technique. After 24 months, 49 of the 58 teeth treated with flowable resin composite and 45 of the 57 teeth treated with flowable compomer were complete, compared to 42 of the 52 teeth treated with the conventional preventive resin technique. There were no statistically significant differences in retention rates among all groups after 3, 6, 12, 18 or 24-months (p>0.05). One tooth treated with flowable resin composite and one tooth treated with flowable compomer developed caries after 18 and 24 months, respectively, resulting from partial loss at "caries-free fissures." Five teeth developed caries in the conventional preventive resin group; one after 12 months, two after 18 months and one after 24 months, due to loss at cavities. The final caries occurred after 24 months, resulting from partial loss at "caries-free fissures." The differences in caries development among the three groups were not statistically significant (p>0.05). This study suggested that flowable resin composite and flowable compomer could be used for preventive resin restorations. Meanwhile, a vigilant recall should be followed-up due to the risk of failure for flowable materials in "caries-free" fissures. The repair should be performed immediately, in case the preventive resin restoration develops a fracture or loss. 相似文献