Covered metal stent for tumor obstruction of efferent loop recurrence after gastrectomy

Reports the case of a 60-year-old woman who underwent R2 total gastrectomy, and subsequent palliation of painful symptom recurrence via a membrane-covered metal stent. Received: 13 June 1996/Accepted: 31 July 1996     

Cobalt-dependent potentiation of net inward current density in Helix aspersa neurons.

A low concentration of transition metal ions Co2+ and Ni2+ increases the inward current density in neurons from the land snail Helix aspersa. The currents were measured using a single electrode voltage-clamp/internal perfusion method under conditions in which the external Na+ was replaced by Tris+, the predominant external current carrying cation was Ca2+, and the internal perfusate contained 120 mM Cs+/0 K+; 30 mM tetraethylammonium (TEA) was added externally to block K+ current. In the presence of Co2+ (3 mM) or Ni2+ (0.5 mM) inward Ca2+ currents were stimulated normally by voltage-dependent activation of Ca2+ channels. There was a 5-10% decrease in the rate of rise of the inward current. The principal effect of Co2+ and Ni2+ in increasing the current density seems to be a decrease in the rate at which the inward currents decline during a depolarizing voltage pulse. The results may be due to a decrease in a voltage-dependent or Ca(2+)-dependent outward current and/or an inhibition of Ca2+ channel inactivation. Outward current under these conditions (zero internal K+) was significant and most likely due to Cs+ efflux through the voltage-activated or Ca(2+)-activated nonspecific cation channels. Co2+ is an extremely effective blocker of this outward current. These results are not an artifact of internal perfusion or the special ionic conditions. Intracellular recording of unperfused neurons in normal Helix Ringer's solution showed that the Ca(2+)-dependent action potential duration was increased significantly by low concentrations of Co2+. This result is consistant with the Co(2+)-dependent increase in inward (depolarizing) current seen in voltage-clamp experiments.     

胶原基真皮再生支架的微结构控制

综述了影响胶原基真皮再生支架微结构的各种因素及其控制方法。胶原基真皮支架的生物活性和修复创面的能力受到诸如除胶原外的其它主要材料 (第二组分 )、支架的孔径和孔隙率、支架厚度、生物活性因子以及交联度等多方面因素的综合影响。从材料学、生物学和医学的角度综合地应用物理、化学和生物学的手段探索各种影响因素的控制方法是组织工程皮肤研究的重点。     

可吸收冠脉支架耐疲劳评价体系的研究

目的:建立可吸收支架耐疲劳测试的评价体系,为可吸收冠脉支架的安全性和有效性评价提供测试手段.方法:模拟人体血管内的受力、温度和腐蚀环境,在1.2 Hz频率下,对可吸收冠脉支架进行18662400次脉动的疲劳实验,相当于植入人体6个月.实验结束后对支架的整体情况和微观形态进行观测.结果:支架在疲劳实验后,未出现移位、弯曲...     

金属雕塑的历史沿革

人类进入文明社会之际 ,硬度远远高于陶器的青铜器 ,有力地促进了人类的文明进程。铁器的出现和广泛使用 ,极大地促进了社会生产力的发展 ,导致封建社会的建立和奴隶制社会的崩溃。大工业革命的历史巨轮隆隆行驶在用新的金属材质“钢”制成的轨迹上 ,崭新的历史纪元伴随日新月异的现代科学技术的急速发展 ,不断为人类拓展着新的生活空间 ,金属在人类历史上所起的重要作用 ,超越了艺术的领域 ,甚至成为人类社会文明进步的一种标识。     

基于三维CT图像重建研制纳米仿生骨基质支架的研究

[目的]分析数字化影像学技术辅助研制生物支架的可行性,评估构筑生物支架的方法.[方法]通过对宿主部位图像扫描,获取该区域解剖数据,对相邻层匹配轮廓间三维表面进行重构来确定支架形貌,以纳米级无机成分为单位,附于壳聚糖及聚己内酯等天然-有机成分,研制纳米复合支架.观察支架形貌、测定支架的孔隙率、亲水性及降解力学特性.[结果]图像三维重构可提高支架外部轮廓的精确度,减少单纯理化制备过程的参数误差,使支架空间三维布局更加合理,孔径200～350 μm,孔隙率88.6%±0.43%的支架拥有稳定的降解速率及良好的亲水表面,可达到工程化骨支架的力学要求,能作为骨再生修复的载体框架.[结论]数字化影像学技术研制的支架具有稳定的理化性征,能解决与宿主部位相匹配的难题,具有潜在的研究空间.     

可吸收钉棒治疗粉碎性桡骨头骨折

目的探讨可吸收钉棒治疗粉碎性桡骨头骨折的疗效。方法对21例MasonⅢ、Ⅳ型桡骨头骨折患者施行切开复位可吸收钉棒内固定。结果 21例均获随访,时间5～35（20.5±9.6）个月,按B roberg和Morrey的肘部评分标准评判：优6例,良13例,可2例。结论可吸收钉棒治疗粉碎性桡骨头骨折操作简便,疗效确切,不需二次手术,具有临床优势。     

Massive acetabular bone loss: Limits of trabecular metal cages

Massive acetabular bone loss (more than 50% of the acetabular area) can result in insufficient native bone for stable fixation and long-term bone ingrowth of conventional porous cups. The development of trabecular metal cages with osteoconductive properties may allow a more biological and versatile approach that will help restore bone loss, thus reducing the frequency of implant failure in the short-to-medium term. We report a case of massive bone loss affecting the dome of the acetabulum and the ilium, which was treated with a trabecular metal cage and particulate allograft. Although the trabecular metal components had no intrinsic stability, they did enhance osseointegration and incorporation of a non-impacted particulate graft, thus preventing failure of the reconstruction. The minimum 50% contact area between the native bone and the cup required for osseointegration with the use of porous cups may not hold for new trabecular metal cups, thus reducing the need for antiprotrusio cages. The osteoconductive properties of trabecular metal enhanced allograft incorportation and iliac bone rebuilding without the need to fill the defect with multiple wedges nor protect the reconstruction with an antiprotrusio cage.