140例维吾尔族百岁老人下颌骨体表测量的观察

目的：观察下颌骨体有无增龄变化及其相关因素。方法：对１４０例维吾尔族百岁老人采用对一侧下颌骨体表直接测量长度及高度，并进行统计学处理。结果：一侧下颌骨体表长度在８．５ｃｍ～１３．０ｃｍ，高度在１．５ｃｍ～５．０ｃｍ，青年组长度大于百岁组（Ｐ＜０．００１），男性组长、高度大于女性组（Ｐ＜０．０１），有牙颌组长高度大于无牙颌组（Ｐ＜０．０１），正常舌组下颌骨长度大于裂纹舌组（Ｐ＜０．０５），但高度无显著性差异（Ｐ＞０．０５）。结论：下颌骨长高度具有生理变化，同时年龄、性别、有无牙列亦有影响，裂纹舌可能与下颌骨缩小有关。百岁老人有下颌骨体增龄表现     

弹性模量和初始应力对种植体骨界面应力分布影响的三维有限元分析

目的:分析种植体弹性模量与骨界面应力分布的关系。方法:用三维有限元的方法对不同弹性模量种植体在各种载荷下骨界面的应力大小和分布进行分析。结果:种植体周围界面骨组织应力强度随着材料弹性模量的增大而增大。结论:低弹性模量的钛合金材料作为种植材料时具有更好的生物力学相容性。初始应力在分析种植体骨界面应力分布时必须加以考虑。     

Simultaneous flapless implant placement and peri-implant defect correction: an experimental pilot study in dogs

BACKGROUND: Minimally invasive implant surgery allows clinicians to place implants in less time, without extensive flaps, and with less bleeding and postoperative discomfort. The purpose of this study was to evaluate a new surgical technique by which implants are inserted in a deficient alveolar ridge using a flapless technique simultaneously with a peri-implant defect correction that is performed using a subperiosteal tunneling procedure. METHODS: Bilateral, horizontal defects of the alveolar ridge were created in the mandibles of five mongrel dogs. After 3 months of healing, one implant was placed on each side of the mandible by a flapless procedure. The exposed threads of the implant on one side of the mandible were covered with a 1:1 autogenous bone/xenograft mixture using a subperiosteal tunneling technique. Four months later, biopsies of the implant sites were taken and prepared for ground sectioning and analysis. RESULTS: All implants were well osseointegrated with the host bone. All of the peri-implant defects at the test sites were covered with tissue that resembled bone. In all specimens, a mixture of bone, connective tissue, and residual bone particles was observed in the graft area. In the control sites, where no graft was used, none of the exposed threads on any implants were covered with new bone. CONCLUSION: This preliminary report indicates the potential use of a minimally invasive flapless technique as a substitute for a more invasive implant placement and ridge augmentation procedure.     

Brain activation patterns during unilateral premolar occlusion

Objective: To observe the characteristics of brain activation during unilateral premolar occlusion.

Methods: Functional magnetic resonance imaging was collected from 10 healthy volunteers during occlusion of the left first premolar (L1), left second premolar (L2), and right first premolar (R1). The brain activation patterns were analyzed, and the primary sensorimotor cortex, supplementary motor area, insula, thalamus, and prefrontal cortex were chosen as regions of interest.

Results: Single premolar occlusion activated the precentral gyrus, postcentral gyrus, cerebellum, thalamus, frontal lobe, hippocampus, cingulate gyrus, and parietal lobe. The brain areas showing activation during single premolar occlusion were similar to those activated by chewing. The activation pattern of L1 was more similar to that of L2 than R1. No significant left and right hemisphere differences in signal intensity were detected within the regions of interest.

Conclusion: Brain activation patterns from two ipsilateral premolars were more similar than the pattern from a contralateral premolar.     

胶囊粉对可见光固化复合树脂机械性能的影响

目的:改善光固化复合树脂的强度和抛光性能.方法:我们采用悬浮聚合法研制了微胶囊型复合填料粉(MCP),作为光固化改进型(VLC-Ⅱ型)复合树脂的填料.并对其性能进行了测试.结果:在复合树脂中加入15%的胶囊型填料粉,压缩强度可达232.1±9.1MPa,拉伸强度可达48.7±2.3MPa,70000次牙刷磨耗率为0.588%,表面粗糙度为2.8μm.结论:胶囊粉可以显著改善复合树脂的压缩强度,拉伸强度,磨耗及表面抛光性等机械性能.与其它同类产品比较,其机械性能、磨耗性能和表面抛光性能均较优越,且相差显著.     

涎腺腺样囊性癌中p16蛋白,增殖细胞核抗原(PCNA)染色与病理分型、神经侵犯和复发的关系

目的 :探讨涎腺腺样囊性癌中 p16蛋白与PCNA在染色与病理分型、神经侵犯、复发中的关系。 方法 :利用免疫组化SP法 ,对 5例正常涎腺组织和 3 6例涎腺腺样囊性癌组织p16蛋白及PCNA染色进行检测 ,并对患者进行 10年随访观察。结果 :3 6例腺样囊性癌中 ,不同病理分型癌细胞组织中 p16蛋白阳性染色率间差异有统计学意义 (P <0 .0 5 ) ,PCNA阳性染色率间差异无统计学意义 (P >0 .0 5 ) ,有无神经侵犯癌组织中 p16蛋白阳性染色率间差异无统计学意义 (P >0 .0 5 )。有无复发癌组织中p16蛋白阳性染色率间差异有统计学意义 (P <0 .0 5 )。PCNA阳性染色率间差异有统计学意义 (P <0 .0 5 )。结论 :p16基因突变、缺失与腺样囊性癌病理类型有关 ,其表达水平反映肿瘤组织分化程度。p16蛋白及PCNA表达水平可以作为临床评价肿瘤侵袭性和预测复发的指标     

Establishment of cell free conversion system with biotin-labelled recombinant PrPsen expressed in E. coli

Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein （HaPrP） was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrP^sen preparation from scrapie strain 263K. Results Protease-resistant bands were detected after four-day incubation. Conclusion The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies.     

158例糖尿病足病原菌分布与创面特点的关系

目的 分析糖尿病足住院患者创面的病原菌分布、药敏情况及其与创面特点之间的关系.方法 选取2017年1月至2019年12月该院急诊外科糖尿病足住院患者158例作为观察对象,取足部创面深部组织,行微生物培养及药敏试验.结果 糖尿病足患者Wagner2、3级创面革兰阳性菌菌株(2级22株,3级30株)多于革兰阴性菌菌株及真菌,Wagner4级创面革兰阴性菌菌株(44株)多于革兰阳性菌菌株及真菌,Wagner 5级共培养细菌2株均为革兰阴性菌.革兰阳性菌对万古霉素、替考拉林、利奈唑胺、替甲环素的敏感度为100％,革兰阴性菌对亚胺培南、美罗培南、庆大霉素、氨基糖苷类的敏感度较高.结论 糖尿病足患者创面病原菌以革兰阳性菌为主,糖尿病足Wagner分级越高,革兰阴性细菌、真菌感染率逐渐升高.     

几种消毒剂对藻酸盐印模材料的消毒效果

作者为了选择对藻酸盐印模材料有效的消毒剂和消毒方法，采用２％碱性戊二醛、１％过氧乙酸、２％甲醛对３０名受试者的藻酸盐印模进行消毒，并在消毒前后进行细菌培养及鉴定。结果发现：消毒前的印模有９种细菌被检出，污染率高达９６％；消毒后的印模细菌检出率为零。作者认为，本研究所用消毒剂、消毒方法效果良好，值得沿用。