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1.
Central illustration: cumulative major adverse cardiac events (MACE) and bioresorbable vascular scaffold (BVS) thrombosis rates after 1, 2, 3, 4 and 5 years.
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背景:组织工程是一个多学科研究的交叉学科,其目标是使人体损伤的组织和器官再生,通过这种假设,几乎所有的动物组织都可以在实验室进行培养。一般的方法是从需要移植的患者身上提取干细胞,在一定的支持条件下允许其生长、增殖、生产为可替换的组织。另一方面,寻找细胞能够互相联结并形成分层结构的合适的支持条件,如基质或支架等非常必要。目前用于烧烫伤治疗的材料有很多种,如胶原,透明质酸、纤维蛋白和聚乳酸及其共聚物。 目的:讨论以新型的生物材料自体血浆为支架对自体成纤维细胞和角质化细胞生长、扩张、增殖的影响。 设计:建立一种真皮再生的方法,将自体成纤维细胞浸于人血浆基质中,排除各种影响样本安全性和排斥反应的问题,应用同样的方法在新的真皮上获取角质化细胞。 时间及地点:实验于2008年在意大利曼多瓦C. Poma医院动物工厂完成。 材料:人角质化细胞和成纤维细胞取自1例58岁乳房切除患者的皮肤碎片。实验得到C. Poma医院独立伦理委员会批准,患者知情同意。 方法:从自体活组织皮肤样本中分离人角质化细胞和成纤维细胞,置于培养瓶中增殖,随后将自体血浆作为皮肤移植形成构造的支架,免疫和免疫组织化学特征显示与正常皮肤相似。 主要观察指标:将血浆样本用甲醛固定,埋入石蜡,苏木精-伊红染色,用显微镜进行细胞计数。所有样本均经免疫组织化学评估。 结果:在血浆基质上获得了多层规则形状的角质化细胞和成纤维细胞,基底膜的形成说明自体血浆是角质化细胞和成纤维细胞的生长、分化、扩展的良好支架,真皮和表皮细胞联结重建皮肤移植与正常皮肤无异。 结论:血浆作为角质化细胞和成纤维细胞分化、扩展的支架表现出良好的性能,同时实验还特别发现成纤维细胞浓缩血浆可以暂时替代皮肤,也是角质化细胞生长的强有力的支架。此外血浆还具有廉价,易于制备等优点。自体角质化细胞和成纤维细胞及自体血浆的应用,可以避免血种类型的免疫排斥反应。这种治疗方法给有慢性缺损并且需要连续移植的患者带来了希望。 doi:10.3969/j.issn.1673-8225.2009.47.001  相似文献   
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Scleroderma is a chronic disease that has been associated with immune dysfunction. One of the oral manifestations is microsomia, a result of collagen deposition in the perioral tissues. The complexity of treating these patients includes limited mouth opening ability, and difficulty inserting and removing dentures due to finger deformity. This article will describe an appliance specially designed especially for scleroderma patients, which facilitates treatment of the patient with removable partial dentures (RPD).  相似文献   
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应用蒙特卡洛法仿真辐射式金属换热器内的辐射传热过程,建立了换热器综合传热的数学模型,利用概率论原理,把辐射能迁移过程仿真为一定累积概率分面下的随机过程,该模型能较好地反映换热器内传热过程的真实情况,可以计算出换热器内烟气、筒壁、空气的温度和壁面热流分布,以及研究烟气进口温度、换热器筒径和狭逢宽度对换热效果的影响。  相似文献   
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目的:研究膨体聚四氟乙烯(ePTFE)植入动物体内后与机体的关系。方法:管状膨体聚四氟乙烯两端闭合,内充DMEM培养液,埋入家兔皮下,观察宿主生命情况,于术后1、2、4、6周取出标本,行大体及光镜下观察。结果:家兔在植入膨体聚四氟乙烯材料及DMEM培养液后存活情况良好,DMEM培养液在1周时即已完全无色透明;4周时膨体聚四氟乙烯与周围组织有粘连,6周时粘连紧密;光镜下观察,各时间点材料间隙均可见着色,1周时可见少量淋巴细胞浸润,无血管及组织细胞。材料内壁未见细胞附着。结论:植入膨体聚四氟乙烯材料及少量DMEM培养液对宿主动物存活无影响;管内外液体可相互交通,管状膨体聚四氟乙烯可作为组织工程化尿道的支架材料。  相似文献   
7.
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  相似文献   
8.
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.  相似文献   
9.
用循环伏安法研究了吡咯在不同金属基底不同支持电解质中的聚合过程,对不同基底上制备的聚吡咯膜进行了电化学、扫描电镜、表面能谱等方面的研究,考察了聚吡咯膜电极对NO_3-离子的电位响应情况,结果表明,不同基底不同支持电解质在不同的吡咯浓度中表现出各异的伏安行为,经电化学处理的聚吡咯膜电极均对NO_3-呈Nernst响应,扫描电镜观察表明除Pt基底外在其它基底上制备的聚吡咯膜均呈颗粒性球状堆集。  相似文献   
10.
Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents at the same time as the initial laparoscopy. Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome measure was complications rates. Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was 3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction, and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified: one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications. Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct.  相似文献   
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