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31.
Wei-Guang Zhang Linpei Jia J. Ma S.-Y. Zhu S.-S. Nie K.-K. Song X.-M. Liu Y.-P. Zhang D. Cao X.-P. Yang D.-L. Zhao M.-J. Xiu L. Lin Z.-X. Li Q. Huang X.-Z. Chen L. Chen P. Wang X.-J. Bai Z. Feng B. Fu J. Huang J.-P. Zhang Guangyan Cai X.-F. Sun Xiangmei Chen 《The journal of nutrition, health & aging》2018,22(2):276-281
Objectives
We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.Methods
The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.Results
Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.Conclusion
The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.32.
总义齿、覆盖义齿和种植覆盖义齿修复后咀嚼效率和下颌运动型的比较 总被引:7,自引:0,他引:7
目的 比较总义齿 (completedenture ,CD )、覆盖义齿 (completeoverdenture ,COD )和种植覆盖义齿 (implant supportedoverdenture ,IOD)修复后患者的咀嚼效率和下颌运动轨迹的差异。 方法 分别选取CD、COD和IOD修复后患者各 14名 ,在义齿正常戴用半年后测量患者的咀嚼效率和下颌运动轨迹。对下颌运动轨迹从规则程度、末端集中性、额状面的分型和咀嚼运动中的接触滑动4个方面进行评价 ,测试用食物为杏仁和小枣。结果 IOD组患者咀嚼枣和杏仁的效率均显著高于CD组 (P <0 0 1) ;COD组患者咀嚼杏仁的效率显著高于CD组 (P <0 0 1)。COD组患者咀嚼枣的效率高于CD组 ,且IOD组患者咀嚼枣和杏仁的效率高于COD组 ,但其间差异无显著性。IOD组患者下颌运动轨迹的规则程度显著优于CD组 (P <0 0 5 ) ,末端轨迹集中性也显著优于CD组 (P <0 0 1)。结论 IOD和COD修复有利于提高无牙颌患者或口内只保留个别残根患者的咀嚼效率。IOD修复患者较CD修复患者具有更加规则的下颌运动型。 相似文献
33.
34.
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
35.
Jinxin Zheng Zhou Wu Kaijun Niu Yanan Xie Xiaoli Hu Jieni Fu Dongtao Tian Kaiyu Fu Bo Zhao Weiyang Kong Cuicui Sun Ligeng Wu 《Journal of endodontics》2019,45(3):302-309.e1
Introduction
This study examined the identity of the microbiome of deep dentinal caries and its correlation with the inflammation status of caries-induced pulpitis.Methods
Seventy-five cases were diagnosed based on the American Association of Endodontics's diagnostic criteria and divided into 4 groups: normal pulp with deep caries (NP; n = 13), reversible pulpitis with only cold-evoked pain (CRP; n = 17), reversible pulpitis with both cold/heat-evoked pain (CHRP; n = 24), and symptomatic irreversible pulpitis (SIP; n = 21). Samples were sequenced by 16S rDNA. Alpha and beta diversity were determined. Linear discriminant analysis effect size (LEfSe) analysis was used to detect intergroup differences, and receiver operating characteristic (ROC) curves were generated to assess the role of the caries microbiome in caries-induced pulpitis.Results
The 16S rDNA sequencing yielded 9100 operational taxonomic units. Lactobacillus had the highest relative abundance at the genus level among the 4 groups. There were significant differences in the distribution of the microbiome among the groups. In an alpha diversity analysis, species richness differed between the CRP group and the other groups. In a beta diversity analysis, the distribution of microorganisms in the SIP group was significantly different from those in the other 3 groups. LEfSe analysis indicated substantial differences in the microbiome among the groups, and the areas under the ROC curves (AUC) were all high (AUC: 0.734–0.952).Conclusions
Characterization of the caries microbiome has the potential to become an auxiliary method for the diagnosis of pulpitis. This finding may prompt new research on diagnostic strategies for caries-induced pulpitis. 相似文献36.
Selective laser sintering technology for customized fabrication of facial prostheses 总被引:3,自引:0,他引:3
This article describes the use of SLS to produce a wax prototype for the fabrication of a partial nasal prosthesis. This technique may be an alternative to more conventional laboratory techniques for facial prosthesis fabrication and allows direct generation of definitive wax patterns. With the satisfying effect of nasal defect restoration, patients may be effectively rehabilitated and derive emotional and physical benefit from the treatment provided. 相似文献
37.
高角儿童面颈部肌肉的肌电活动研究 总被引:1,自引:0,他引:1
目的研究高角儿童在不同下颌运动时面颈部肌肉的肌电活动情况。方法用BioEMGⅡ型肌电图仪同步记录14名高角儿童和16名均角儿童在不同下颌运动时双侧颞肌前束(TA)、咬肌(MM)、胸锁乳突肌(SCM)和二腹肌前腹(DA)的肌电活动。结果下颌息止位时,高角组TA、DA和SCM的肌电活动低于均角组,有统计学意义(P<0.01,P<0.05);最大紧咬时,高角组TA和MM的肌电活动低于均角组,有统计学意义(P<0.05);咀嚼口香糖时,高角组MM的肌电活动低于均角组,有统计学意义(P<0.05);吞咽时高角组DA的肌电活动低于均角组,有统计学意义(P<0.05)。结论不同下颌运动时,高角儿童和均角儿童面颈部肌肉的肌电活动差异有所不同;面颈部肌肉的肌电活动可能与颅面垂直形态有关。 相似文献
38.
牙周炎患者龈沟液和龈组织中IL—8的测定 总被引:1,自引:0,他引:1
采用ELISA间接夹心法测定了23名成人牙周炎患者34个患牙龈沟液中的IL-8.并用免疫组织化学法对相应的炎性龈组织进行检测.结果表明IL-8与牙周炎症密切相关,牙周炎龈沟液(GCF)中IL-8检出率为88.24%.IL-8含量范围为0.006~2.772ng/μl.其含量与牙龈指数相关非常显著,与牙周袋深度相关显著,与附着丧失、菌班指数无明显相关.炎性龈组织切片染色表明龈上皮组织和胶原组织中含有大量的阳性染色,从组织学上证明了GCF中IL-8的来源.提示IL-8可能在牙周炎发病机制中起着重要作用. 相似文献
39.
Li-bin Zhou Hong-tao Shang Man Hu Di-chen Li Sekou Sigare Ben-lan Chen Yan-pu Liu Jin-long Zhao 《The British journal of oral & maxillofacial surgery》2008,46(6):445-448
A new internal distraction device, comprising a square-bodied bow, a transport plate, a traction mechanism, and two stabilisers, was developed to allow transportation of bone around an arc. Eight adult goats were studied. A curved mandibulectomy 3cm long was made on the mandibular angle. The distractor was implanted to restore the defect. The bone was distracted at a rate of 1mm per day after a 5-day latent period. Distraction lasted 25 to 32 days. Curvilinear distraction was successful in six of the eight goats. After consolidation periods of four or eight weeks, smooth curved bone masses were restored in the distracted areas. Radiographically, there was considerable bone density in the distraction area and opaque columns streamed in the direction of distraction. Histological examination showed membranous bony regeneration in the restored bone. These results suggest that restoration of curved bone defects using the new internal transport distraction device was feasible in goats. 相似文献
40.
本章应用简单的称重法对等温吸附曲线和吸附动力学曲线进行了粗略的测定,并应用先进的XPS技术对蛋白质在不同pH值下的解吸特性进行研究。发现材料表面的蛋白吸附量随蛋白溶液的浓度的增加和时间的延长而增加,而且在浸泡最初的吸附量增加最快,尤其在前20分钟,吸附几乎就达到了平衡.还发现钛种植体表面的吸附的能力比317L不锈钢的吸附能力强,几乎同时进入吸附的平衡阶段。在体液pH值状态下,钛表面的蛋白吸附量最高,随着pH值向两侧移动,钛表面的蛋白吸附量在下降,而当pH值为25和12时,表面蛋白吸附量降至最小值,pH值继续升高或降低反而表面蛋白的残余量有所升高。 相似文献