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51.
52.
牙周基础治疗对胃内幽门螺杆菌根除率的影响   总被引:9,自引:1,他引:9  
目的 :分析牙周炎与胃内幽门螺杆菌 (Helicobacterpylori ,Hp)的关系以及牙周基础治疗对胃内幽门螺杆菌根除率的影响。方法 :选择有慢性牙周炎且胃镜活检尿素酶阳性、病理诊断为慢性胃炎、胃或十二指肠溃疡患者91人进行三联药物治疗 ,其中 3 3人还同时进行了牙周基础治疗。三联药物治疗后分析胃内幽门螺杆菌根除率与患者牙周临床指数的关系 ,以及牙周基础治疗对胃内Hp根除率的影响。 结果 :4个位点平均牙周袋深 <4mm组的患者三联药物治疗 4周后及 1年后的Hp根除率明显高于平均袋深≥ 4mm组的患者 (80 %vs5 2 .2 % ,62 .9%vs 3 4.5 % ,P <0 .0 5 )。经过牙周基础治疗的患者 1年后的Hp根除率显著高于未做牙周基础治疗的患者 (63 .6%vs 3 4.5 % ,P <0 .0 5 )。结论 :药物治疗Hp的根除率与患者的牙周状况和口腔卫生状况有关。口腔Hp可能是胃Hp再感染的病原因素 ,因此对胃内Hp感染同时伴有牙周炎的患者在进行三联药物治疗的同时应配合牙周基础治疗。  相似文献   
53.
静态拉伸应变对人牙周膜成纤维细胞的影响   总被引:4,自引:2,他引:4  
目的:研究人牙周膜成纤维细胞(PDLF)在机械拉伸应变作用下,细胞和细胞核投影面积及其细胞骨架的改变情况,探讨PDLF的形态、功能和应变之间的关系。方法:采用自制的细胞体外静态机械加载装置用不同的拉伸应变量加力于细胞上,通过激光扫描共聚焦显微镜观察细胞骨架的形态及其改变情况,并进行统计分析。结果:在8%、12%、16%力值组,细胞和细胞核投影面积随着加力时间和力值的增加而每天递增,肌动蛋白纤维也随之逐渐增粗,排列更有规律;而在20%力值组,其结果则反之。结论:静态拉伸应变可影响牙周膜成纤维细胞的骨架。  相似文献   
54.
为了对上颌尖牙唇向错位进行正确的矫治设计,作者根据错位的病因、X线头影测量结果,对34例上颌尖牙唇向错位病例,分别采用前牙片段方丝辅弓法,改良Richett's弓法,推磨牙向后法,拔除第2乳磨牙法,拔除第一双尖牙法,取得满意结果。作者认为在矫治上颌尖牙唇向错位时,应充分利用潜在间隙,根据X线头影测量结果及错位形成原因进行综合分析,选用最佳方法进行矫治。  相似文献   
55.
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   
56.
应用牵张成骨技术行牙槽嵴增高术的研究进展   总被引:3,自引:0,他引:3  
牵张成骨 (distractionosteogenesis,DO)指在骨缝处或在截开的骨段用牵张装置按一定的速度和频率牵开 ,因此产生的骨间隙中形成新骨 ,从而达到使骨延长或增宽的目的。该技术用于四肢长骨已有近百年历史 ,在颅面部治疗颌骨缺损、畸形及阻塞性睡眠呼吸暂停综合征等领域也获得了成功。近年来 ,用牵张成骨技术增高牙槽嵴逐渐成为研究热点 ,现综述如下。一、牵张成骨技术与传统牙槽嵴增高术的比较牙槽嵴增高术分相对增高及绝对增高两种 ,前者指唇颊沟加深或牙槽嵴延伸术 ,后者指牙槽嵴增高术。唇颊沟加深术通过改变黏膜及肌附着的位置 ,使牙槽嵴…  相似文献   
57.
The negatively charged polymer polyester sulfonic acid (Eastman-AQ, abbreviated to AQ), positively charged polymer polyvinyl pyridine (PVP) and mediator Os(bpy)32+ were used to construct composite modified glassy carbon (GC) electrodes (abbreviated to GC/AQ-Os(bpy)32+-PVP). The reduction of NO2? in acidic solution was taken as a model reaction to explore the properties of the modified electrode. On the steady state polarization curve of NO2? reduction there were two well-developed waves with much enhanced plateau current densities and positively shifted half-wave potentials compared with bare GC electrodes. In 0.05 mol/l H2SO4 + 5 mmol/l NO2? the modified electrode exhibited plateau current densities of 723 and 1153 μA cm?2 and half-wave potential shifts of 0.29 and 0.56 V for the first and second current wave, respectively, showing promising potential for nitrite detection. The catalytic activity for NO2? reduction did not decrease appreciably over 4 months. A number of relevant kinetic and thermodynamic parameters are estimated experimentally. NO2? reduction at the composite modified electrodes is suggested to follow the SR mechanism (pure kinetic conditions involving mutual compensation between a catalytic reaction and substrate diffusion in the film in addition to diffusion in the solution phase) according to the Savéant–Andrieux theory.  相似文献   
58.
In Asia, a round face rather is more acceptable than a square face. Intraoral mandibular angle ostectomy is a common aesthetic procedure for correcting a prominent mandibular angle. However, an operation of sheer straight-lined prominent mandibular angle resection would sometimes create extramandibular angles or palpable bone steps in the margin of mandibular body and produce unnatural lower one-third facial appearance, especially for a square and disproportional mandibular angle even extending to the middle mandibular body. This article describes the method of multistage mandibular angle ostectomy to produce a natural lower one-third facial contour. This method mainly focused on the posterior area of mandibular ostectomy by intraoral approach, although it has modifications. Mandibular contouring is realized first through bone cutting from antegonial notch posteriorly upperward, reaching to the middle ramus of the mandible near the earlobe; second ostectomy followed along mandible lower part is to get rid of extramandibular angle according to the preoperative design; sometimes necessarily, third ostectomy creates a smooth mandibular contour. From January 2000 to January 2010, 379 patients were operated on, and satisfactory results were achieved. Thus, this procedure could avoid excessive bone cutting, extramandibular angles, unnatural appearance, and palpable bone steps.  相似文献   
59.
Cell-mediated immunity is important for anti-Candida host defence in mucosal tissues. In this study we used cytokine-specific gene knockout mice to investigate the requirement for T helper type 1 (Th1) and Th2 cytokines in recovery from oral candidiasis. Knockout mice used in this study included interleukin-4 (IL-4), IL-10, IL-12p40, interferon-gamma (IFN-gamma), and tumour necrosis factor (TNF). The mice were challenged either orally or systemically with Candida albicans yeasts, and levels of colonization were determined. IL-12p40 knockout mice developed chronic oropharyngeal candidiasis, but were not more susceptible to systemic challenge. On the other hand, TNF knockout mice displayed increased susceptibility to both oral and systemic challenge, but only in the acute stages of infection. TNF apparently has a protective effect in the acute stages of both oral and systemic candidiasis, whereas IL-12p40 is essential for recovery from oral but not systemic candidiasis. The role of IL-12p40, and its relation to T-cell-mediated responses remain to be determined.  相似文献   
60.
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