Classification and cyclic fatigue evaluation of new kinematics for endodontic instruments

This study evaluated the effect of new motions of the motor TriAuto ZX2 on the cyclic fatigue of endodontic instruments. Vortex Blue 35.06 instruments were divided into four groups (n = 10) and tested for fatigue in a curved artificial canal (90° and 2 mm radius) using the following motions: continuous rotation (CR), Optimum Torque Reverse (OTR) set at 180° and the Optimum Glide Path (OGP), which was tested at 90° and 240°. The time to fracture (TTF) and the lengths of the fractured fragments were recorded. The mean TTF was significantly different among the groups (anova , P < 0.05): OGP 90° (213.39 ± 27.45), OTR 180° (121.24 ± 17.03), OGP 240° (45.24 ± 5.61) and CR (8.43 ± 1.27). Weibull analysis confirmed the shortest life expectancy for CR and the longest survival for OGP at 90°. The resistance to fatigue was affected by motions and pre‐set angles. The proprietary movements that are currently available for endodontic instruments were classified according to their kinematics.     

Diagnostic sensitivity of electrophysiology and ultrasonography in ulnar neuropathies of different severity

ObjectiveTo assess the diagnostic performance of electrophysiology and nerve ultrasound in ulnar neuropathies of varying clinical severity in 135 consecutive patients.MethodsClinical severity of ulnar neuropathy was graded on a 4 point scale from very mild (symptoms only) to severe (marked atrophy of intrinsic hand muscles). Sensitivity and localization ability of electrophysiology and nerve ultrasound were assessed for each point of the scale.ResultsUltrasound had higher sensitivity than electrophysiology in clinically very mild (20% and 3% for ultrasound and electrophysiology, respectively) and mild (62% and 47% for ultrasound and electrophysiology, respectively) neuropathies, had greater localizing ability in axonal ulnar neuropathies, and identified nerve hypermobility.Ultrasound nerve cross-sectional area had strong positive correlation with both clinical and electrophysiological severity scores, but with significant overlap across the severity groups.ConclusionThe diagnostic work-up of ulnar neuropathies was improved by using both electrophysiology and ultrasound at all levels of clinical severity. Ultrasound increased the diagnostic yield in very mild and mild neuropathies, localized all the ulnar neuropathies with abnormal non-localizing electrophysiology and identified nerve hypermobility.SignificanceThis is the first detailed analysis of the diagnostic performance of electrophysiology and ultrasound in ulnar neuropathies of varying severity.     

注射后臀肌挛缩症的分型及手术治疗

目的 探讨注射后臀肌挛缩症的分型、分型与病变的关系和手术范围。方法 根据臀肌挛缩症特有的临床表现.分为轻型、中型、重型：根据分型术中分别显露髂胫束、臀大肌、臀中肌、臀小肌至髋关节囊后方。结果 153例均手术治疗，随访141例、随访时间1～10年，平均6．8年，优良率96．5％。结论 将臀肌挛缩症进行分型？更有利于准确的区别病情轻重程度，选择相应的手术范围和评估预后。     

运动疲劳对大鼠十二指肠电活动的影响

本文报道了大鼠十二指肠电活动在运动疲劳前后的数值。结果表明：在运动疲劳后，快波、慢波振幅明显增加，而其频率却减少；Ⅰ相缩短，Ⅱ相延长，Ⅲ相、Ⅳ相及ＩＤＭＥＣ周期无显著变化；并在运动疲劳后９．７±２．４ｍｉｎ内出现不规律的食后型的电活动。这些改变可了解运动疲劳对消化系统的影响。     

肿瘤抑制因子PTEN蛋白在自发性高血压大鼠主动脉平滑肌中的表达

目的：研究PTEN蛋白在雄性自发性高血压大鼠及SD大鼠主动脉中的表达。方法：取18周龄和26周龄雄性自发性高血压大鼠及同龄雄性SD大鼠主动脉石蜡包埋切片，免疫组织化学观察PTEN在主动脉平滑肌细胞中的表达。结果：SD大鼠主动脉平滑肌细胞中存在PTEN阳怀免疫反应产物。自发性高血压大鼠主动脉平滑肌细胞也存在PTEN阳性免疫反应产物，但免疫反应产物的染色强度明显低于SD大鼠。结论：SD大鼠主动脉平滑肌细胞PTEN高表达，自发性高血压大鼠主动脉平滑肌细胞PTEN表达呈下降趋势。提示PTEN可能在自发性高血压大鼠主动脉平滑肌细胞重塑过程中发挥作用。     

腭裂修复术腭咽肌肉重建与否的鼻咽内窥镜的比较观察

目的通过是否进行腭咽肌肉重建的两组腭裂修复术后患者鼻咽内窥镜的比较观察,了解腭咽部肌肉重建术后腭咽闭合状况的改变。方法将41例腭裂术后患者,按照在腭裂修复时是否进行腭咽肌肉重建分为重建组(22例)和非重建组(19例),以鼻咽纤维内窥镜记录静态和发音时腭咽闭合运动状况,对两组患者腭咽闭合运动类型和状况进行比较。结果重建组静态腭咽腔形态较非重建组明显缩小,各壁光滑丰满,未见软腭鼻腔面V型缺损畸形;动态时以环状闭合为主。非重建组静态腭咽腔形态较大,可见软腭鼻腔面V型缺损畸形;动态时以冠状闭合为主。经比较重建组腭咽闭合良好率(90.91%)明显优于非重建组(37.31%)。结论鼻咽内窥镜观察证实腭咽肌肉重建腭裂修复术后腭咽闭合功能恢复明显优于非重建组。腭裂修复术时重建腭咽肌肉有助于缩小腭咽腔和更易于达到良好的腭咽闭合状态。     

三氧化二砷纳米微粒对抑制兔血管平滑肌细胞增殖作用的实验研究

目的 了解纳米微粒与普通剂型的三氧化二砷（As2O3）对抑制体外培养的兔血管平滑肌细胞（VSMC）增殖作用的差别。方法 对照组为不加药物的细胞，实验组为3μmol／L纳米微粒和普通剂型的As2O3，干预体外培养的兔VSMC细胞72h，进行四唑氮盐（MTT）染色测定细胞吸光度（A）值。用流式细胞仪检测细胞凋亡情况，提取细胞DNA，进行凝胶电泳分析，将3组的结果进行比较。结果 3μmol／L纳米剂型的As2O3，干预细胞，细胞数量随作用时间的延长逐渐减少，细胞生长明显受抑制，而普通剂型干预细胞，生长受抑制程度较纳米剂型弱。24h时，对照组、3μmol／L普通剂型组与纳米组，A值分别为0．68±0．10、0．58±0．12、0．33±0．12，48h时分别为0．79±0．11、0．48±0．14、0．28±0．11，72h时分别为0．96±0．13、0．34±0．15、0．20士0．06，差异均有统计学意义（Ⅳ值分别为10．934、15．039、15．539，P值均〈0．01）。流式细胞仪检测，纳米剂型As2O3、普通剂型As2O3干预及对照组的细胞干预48h，细胞增殖率分别为44．97％、58．54％、74．02％，早期凋亡率分别为16．89％、11．27％、11．20％，晚期凋亡率分别为26．56％、23．60％、12．46％，坏死细胞分别为11．58％、6．59％、2．32％。DNA电泳，As2O3干预细胞，可见凋亡梯形条带，部分细胞坏死，呈模糊的无间隔片状条带。纳米剂型药物作用的细胞DNA条带，梯形条带更多、更模糊。结论 As2O3，可以抑制体外培养的VSMC增殖，且纳米剂型As2O3较普通剂型的As2O3，对细胞抑制作用更强。     

薄壁构件的高温低周疲劳寿命的预测与验证

提出了文题的计算模型,它采用非线性弹塑性蠕变有限元法,计算构件危险点在高温及周期保载的交变载荷谱作用下的应力应变响应,以应变范围区分法累积损伤,从而求出构件的疲劳寿命,并以带孔矩形薄板为例作了计算与验证,结果吻合较好,可供工程应用。     

The laterally extended medial hemisoleus flap for reconstruction of a tibial wound in the distal third of the leg

A soleus flap as a local reconstructive option for soft-tissue coverage of a tibial wound in the distal third of the leg has never been well recognized. In a 2-year period, seven patients underwent reconstruction of a less extensive tibial wound (4 × 3 to 10 × 4 cm) in the distal third of the leg after orthopedic trauma with the laterally extended medial hemisoleus flap. The flap was elevated with emphasis on the preservation of the most distal perforators from the posterior tibial vessels to the flap as possible while allowing adequate rotation of the flap to cover the exposed tibia and/or hardware and on the possible preservation of foot planter flexion by reconstruction of the proximal Achilles’ tendon. In this series, there was no total or partial flap loss. All patients healed their tibial wounds primarily with reliable soft-tissue coverage, evidenced fracture healing, and good cosmetic outcome during follow-up. Thus, the laterally extended medial hemisoleus flap described by the author can be a reliable option for soft-tissue coverage of a less extensive tibial wound in the distal third of the leg. It offers a more cost-effective approach for managing this unique problem and can be performed by most reconstructive surgeons without microsurgical expertise.