Characteristics of implant-CAD/CAM abutment connections of two different internal connection systems

Titanium or zirconium computer-aided design/computer-aided manufacturing abutments are now widely used for aesthetic implant treatments; however, information regarding microscopic structural differences that may influence the biological and mechanical outcomes of different implant systems is limited. Therefore, the characteristics of different connection systems were investigated. Optical microscopic observation and scanning electron microscopy showed different characteristics of two internal systems, namely the Astra Tech and the Replace Select system, and for different materials. The scanning electron microscopic observation showed for the Astra Tech that the implant-abutment interface seemed to be completely sealed for both titanium and zirconium abutments, both horizontally and sagittally; however, the first implant-abutment contact was below the fixture top, creating a microgap, and fixtures connected with titanium abutments showed significantly larger values (23·56μm±5·44 in width, and 168·78μm±30·39 in depth, P<0·001). For Replace Select, scanning electron microscopy in the sagittal direction showed that the sealing of titanium and zirconium abutments differed. The seal between the implant-titanium and implant-zirconium abutments seemed to be complete at the butt-joint interface; however, the displacement of the abutment in relation to the fixture in the lateral direction was evident for both abutments with no statistical differences (P>0·70), creating an inverted microgap. Thus, microscopy evaluation of two commonly used internal systems connected to titanium or zirconium abutments showed that the implant-abutment interface was perfectly sealed under no-loading conditions. However, an inverted microgap was seen in both systems, which may result in bacterial accumulation as well as alteration of stress distribution at the implant-abutment interface.     

斑蝥的生药学研究

目的对芫青科昆虫南方大斑蝥Mylabris phalerata和黄黑小斑蝥Mylabri scichorii中药材性状、微性状、粉末显微及微量升华结晶物显微特征进行研究,为其鉴定工作以及《中国药典》2020年版的制定工作提供科学依据。方法采用性状鉴别法、微性状鉴别法、常规显微鉴别法、偏振光显微鉴别法及微量升华法,对6批南方大斑蝥和4批黄黑小斑蝥进行系统的生药学研究。结果首次获取了南方大斑蝥和黄黑小斑蝥微性状鉴别特征(体长、触角、鞘翅、内翅等)、粉末显微鉴别特征(刚毛、体壁碎片、鞘翅碎片、内翅碎片、肌纤维、气管壁组织、未消化的植物组织)及其微量升华结晶物特征的全息彩色影像数据。结论微性状鉴别研究结果补充完善了传统宏观性状鉴别的细微构造特征,显微及微量升华鉴别研究结果可作为中药材及中成药中斑蝥鉴定的专属性标志物。     

显微镜下多血管炎咯血前胸部CT表现与临床意义

目的 探讨显微镜下多血管炎患者(microscopic polyangiitis,MPA)咯血前的胸部CT影像学特点及其临床意义.方法 回顾性分析30例确诊为MPA的胸部CT影像学表现和临床资料,其中咯血组11例,非咯血组19例,分析咯血组在咯血前的胸部CT影像学特点、临床资料,并与非咯血组对比.结果 30例患者均有不同程度的胸部CT异常表现,其中斑片影13例(43.3％),实变影8例(26.7％),磨玻璃影13例(43.3％);网格影14例(46.7％),胸腔积液20例(66.7％),肺大泡15例(50.0％),纵隔淋巴结肿大11例(36.7％),支气管扩张9例(30.0％),空洞1例(3.3％)为咯血组患者,小叶间隔增厚7例(23.3％)和结节影2例(6.7％)均为非咯血组患者,纤维条索影25例(83.3％).咯血组较非咯血组的斑片影、实变影、磨玻璃影、网格影明显增加(P＜0.05),咯血组患者在初次胸部CT影像学异常表现2～14 d后均出现不同程度的咯血.咯血组患者胸痛、咳嗽咯痰、心累气紧和炎症指标与非咯血组差异有统计学意义(P＜0.05).结论 MPA患者肺部广泛的斑片影、实变影、磨玻璃影、网格影CT表现结合胸痛、咳嗽咯痰、心累气紧和炎症指标升高提示可能出现肺咯血.     

中药小包装饮片的历史源流及其调剂规范化操作的思考

目的传承历代中药调剂操作经验,规范现代中药小包装饮片调剂操作技术。方法通过查阅历代古籍和现代文献,系统整理和分析中药饮片小包装的历史渊源、使用利弊、包装选择、使用现状及调剂规程等五方面情况,回顾小包装饮片的发展历程,总结调剂操作经验,编排现代调剂操作规程。结果中药小包装饮片调剂具有独特的优势,"审、摆、看、对、拿、掂、分、核、包、发"的"十字口诀"是其主要操作要点。结论中药小包装饮片调剂"十字口诀"易记、易懂、易操作,提高临床调剂质量、规范调剂技能具有指导意义。     

UF-5000和UC-3500联合检测尿液有形成分的应用价值探讨

探讨UF-5000全自动尿沉渣分析仪和UC-3500尿干化学分析仪联合在尿液有形成分检测中的应用价值。方法： 收集2870例随机尿液标本,每个标本分成两等份,一份以仪器UF-5000和UC-3500检测,另一份离心显微镜镜检。仪器结果与显微镜结果进行比较分析,评估仪器测定RBC和WBC的检出效能。结果：与显微镜法比较,UF-5000检测尿RBC和WBC的敏感性分别为67.53%和87.25%、特异性分别为95.43%和96.93%、一致性分别为89.48% (Kappa=0.668,P<0.001)和94.84%(Kappa=0.847,P<0.001),假阴性率为32.46%和12.74%。UC-3500检测尿RBC和WBC的敏感性分别为90.37%和78.18%、特异性84.60%和97.47%、一致性分别为85.96%(Kappa=0.669, P<0.001)和93.48% (Kappa=0.793,P<0.001),假阴性率为9.63%和21.82%。UF-5000+UC-3500联合检测尿RBC和WBC的敏感性分别为93.35%和88.54%、特异性分别为82.75%和94.28%、一致性分别为85.37% (Kappa=0.659,P<0.001)和92.99% (Kappa=0.805,P<0.001),假阴性率为6.65%和11.46%（P<0.001)。 结论：联合运用UF-5000和UC-3500尿液分析仪测定可保证尿有形成分分析结果的准确性。     

动力吸切系统在声带显微黏膜瓣手术中的临床效果观察

目的探讨将动力吸切系统应用于声带显微黏膜瓣手术的临床疗效。方法将80例声带息肉患者分为A组（42例）和B组（38例）,均采用显微黏膜内侧微瓣技术手术治疗,A组应用动力吸切系统,B组应用喉显微钳切除病变,于术前和术后3个月进行电子喉镜检查。结果术后3个月A组显效40例,有效2例,显效率为95．24％,总有效率为100．00％：B组显效37例,有效1例,显效率为97．37％,总有效率为100．00％;两组显效率和总有效率差异无统计学意义（P〉0．05）。两组术后均无明显并发症发生。A组平均手术时间为（6±3）min,B组平均手术时间为（11±6）min,两组手术时间差异有统计学意义（P〈0．05）。结论将动力吸切系统应用于声带显微黏膜瓣手术,在取得与传统手术相近疗效的情况下,能降低手术操作难度,减少手术时间,值得临床推广。     

Evaluation of the Effects of Filler Fineness on the Properties of an Epoxy Asphalt Mixture

The type and fineness of a filler significantly affect the performance of an asphalt mixture. There is a lack of specific research on the effects of filler fineness and dust from aggregates on the properties of epoxy asphalt (EA) mixtures. The effects of aggregate dust and mineral powder on the properties of an EA mixture were evaluated. These filler were tested to determine their fineness, specific surface area and mineral composition. The effects of these fillers on the EA mastic sample and mixture were evaluated. The morphology of the EA mastic samples was analyzed using scanning electron microscopy (SEM). The effects of the fillers on the Marshall stability, tensile strength and fatigue performance of the EA mixture were evaluated. The dust from the aggregates exhibited an even particle size distribution, and its average particle size was approximately 20% of that of the mineral powder. The SEM microanalysis showed that the EA mastic sample containing relatively fine dust formed a tight and dense interfacial bonding structure with the aggregate. The EA mixture sample containing filler composed of dust from aggregate had a significantly higher strength and longer fatigue life than that of the EA sample containing filler composed of mineral powder.     

乙型肝炎患者骨髓间充质干细胞培养方法的优化和生物学特性

目的比较乙型肝炎患者骨髓间充质干细胞（MSCs）多种体外培养方法的效果，确定乙型肝炎患者MSCs的最佳体外培养方案；并对其生物学特性进行初步研究。方法比较2种接种方案和5种不同成分培养液的乙型肝炎患者MSCs体外培养成功率。比较5种不同成分培养液和4种换液方案的乙型肝炎患者MSCs生长曲线。进行乙型肝炎患者MSCs的形态观察和表面分子鉴定，传代培养以初步了解其生长特性。结果密度梯度离心接种法的体外培养成功率（88％）高于全骨髓接种法（76％），但差异无统计学意义。5种培养液的体外培养成功率差异有统计学意义（P〈0．01），其中患者自体血清培养液的培养成功率最高（100％），3种FBS培养液的培养成功率次之，健康成人血清培养液的最低（56％）。患者自体血清培养液的MSCs生长曲线最高，健康成人血清培养液的生长曲线最低，3种FBS培养液的MSCs生长曲线集中位于上述两者之间。以2d或者3d一次全量换液的MSCs生长曲线较高。乙型肝炎患者MSCs与正常人MSCs形态相同，表面分子表达一致，生长特性近似。结论乙型肝炎患者MSCs的体外培养方案以密度梯度离心法分离后，自体血清培养液进行培养，2～3d全量换液为佳，可以较快获得纯度较高的MSCs。乙型肝炎患者MSCs的生物学特性和正常人的近似。