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51.
目的:探讨高分子材料和种植体同期植入缺损区进行同步骨缺损修复和牙列缺损修复的可行性。方法:以4只杂种狗为研究对象,制备下颌骨长约2.5cm的缺损的动物模型(保留下颌骨下缘),将骨水泥(聚甲基丙烯酸酯)植入骨缺损,同时将牙种植体植入骨水泥中并调整长轴方向,立即关闭术创。至术后3个月摄X线片,然后处死动物,局部巨检以了解骨水泥同骨组织的结合情况,并制备骨组织切片进行苏木精一伊红染色和甲苯胺蓝染色,以了解植入材料周边骨的生长情况及其对植入材料的反应。结果:术后3个月X线检查见骨缺损区充满骨水泥,骨水泥周边的骨小梁清晰,未见骨吸收或炎症表现,形成良好的骨-骨水泥界面,种植体则依赖其表面的螺纹结构与骨水泥间紧密的机械性嵌合而牢固的成为一体,植入的骨水泥块与周边天然骨结合紧密,无松动现象。植入材料周边局部脱钙骨的苏木精-伊红染色和甲苯胺蓝染色见骨结构正常,同时骨-骨水泥界有新骨形成。结论:骨水泥作为颌骨修复替代材料同期植入种植体是可行的。 相似文献
52.
The measurement of amniotic fluid (AF) acetylcholinesterase isoenzyme (AChEI) is a relatively new method for early diagnosis of open neural tube defects (NTDs). As quantitative methods are of unproven reliability at present, the authors used a high resolving power qualitative method-vertical slab polyaerylamide gel electrophoresis. The benefits of this technique are: simplicity of operation, accuracy, unsophisticated equipment, and easily available reagents. Combined results of 9 NTDs studies revealed that samples from early pregnancy gave more accurate results than those from late pregnancy. 相似文献
53.
54.
连续浅缝法修补膜周型室间隔缺损 总被引:4,自引:0,他引:4
目的探讨连续浅缝法修补单纯膜周型室间隔缺损(pVSD)法的效果。方法选取2002年1月至2004年10月我院收治的体重10kg以内(≤10kg)50例单纯膜周型室间隔缺损患者,均采用自体心包连续浅缝法修补。结果主动脉阻断时间32±21min(14-52min),体外循环时间56±35min(29-69min)。无°房室传导阻滞发生,9例发生右束支传导阻滞,2例结性心律。2例膜周偏流出道型VSD患者因前上缘残余分流分别为0.4cm和0.3cm,再次手术修补;1例后下缘残留细束样分流,直径0.15cm,随访6个月后自愈;10例膜周偏流出道型VSD患者剪开三尖瓣,8例垂直瓣环,2例平行瓣环;1例三尖瓣中度反流,随访无加重;5例轻度反流,4例轻微反流,随访均无加重;1例心包积液;1例再次进入手术室止血。结论连续浅缝法是修补单纯膜周型室间隔缺损的有效外科纠治方法。 相似文献
55.
唇腭裂患者上颌骨牵引成骨术后发音方式的变化 总被引:1,自引:0,他引:1
目的:通过对行颅外支架式上颌骨牵引成骨术(rigidexternaldistraction,RED)唇腭裂患者治疗前后的错误发音数量变化、不同发音部位、不同发音方法以及不同类型错误发音发生特点及其变化评价,分析上颌骨RED对患者发音方式的影响。方法:1999年至2001年行上颌骨RED的唇腭裂术后上颌发育不足患者21例,其中男性13例,女性8例,平均年龄15.05岁。所有患者RED前后进行语音测听并分类。治疗前后错误发音的差异性用非参数检验。结果:RED术后42.9%患者错误发音数较RED前增加,19.0%减少,38.1%无变化。从发音部位,舌尖前音错误发音发生率最高,其次为舌面音。从发音方法,错误发音多发于塞擦音。错误发音类型以咽喉摩擦/爆破音为主,其次为腭化构音和声门爆破音。上颌骨RED后腭化构音累及音节数减少,但咽喉摩擦/爆破音和声门爆破音反而增加,尤其是咽喉摩擦/爆破音。结论:唇腭裂患者经RED前移上颌骨后,会对患者发音方式产生影响,在行语音治疗前需考虑全面。 相似文献
56.
目的 探讨在浅低温体外循环心脏跳动下完成小儿室间隔缺损修补术的可行性。方法 18例小儿室间隔缺损随机分为观察组和对照组 ,观察组在浅低温体外循环心跳下修补室间隔缺损 ,对照组为常规心脏停跳下修补室间缺损。测定心肌同功酶释放和三磷酸腺苷 ,观察左室压力 ,评价术野显露及气栓预防效果等。结果 观察组心肌同功酶释放明显低于对照组 ,三磷酸腺苷含量明显高于对照组 ,心肌超微结构基本正常 ,术中左室压力低于主动脉压力 ,术后无气栓发生。结论 浅低温体外循环心脏跳动下行小儿室间隔缺损修补术能更好地保护心肌。术野显露技术和防气栓的方法简便可行。 相似文献
57.
目的 探讨在临床上上颌第一磨牙近中颊根第二根管(MB2)的发现及扩通。方法 在25例需要进行根管治疗的上颌第一磨牙上寻找MB2,若无法找到,使用超声根管异物清除工作尖10P清理髓底及慢速圆钻去除预计位置部分牙本质,再次寻找。找到后通畅根管,若无法扩通,使用慢速圆钻在MB2根管口处向根方去除少量牙本质。结合使用EDTA再次通畅根管。结果 25颗治疗齿中有13颗找到MB2(52%),其中2颗是在超声根管锉清理髓室底后发现的,4颗在进一步去除MB2根管口位置的牙本质后发现。8颗治疗齿的MB2通畅(32%),其中3颗自然扩通,5颗在去除MB2根管口处部分矛本质并使用EDTA后通畅。结论 临床上上颌第一磨牙MB2发现率为52%。扩通率为32%。掌握MB2的解剖位置,使用超声方法以及EDTA可提高MB2的发现率和扩通率。 相似文献
58.
关节镜下应用“微骨折”方法修复关节软骨缺损 总被引:3,自引:3,他引:0
目的:探讨关节镜下应用“微骨折”技术对膝关节全层关节软骨缺损修复的效果。方法:对68例全层关节软骨缺损患者进行随机分组:实验组(35例),男17例,女18例,平均年龄35.1岁,采用关节清理后应用“微骨折”技术进行处理,即利用骨刀设计的特性和适度的锤击力量造成软骨下的骨组织微小骨折,刺激软骨生长。对照组(33例),男17例,女16例,平均年龄31.6岁,仅作关节清理术。结果:术后随访6~18个月,平均8.6个月,按Lysholm评分标准,实验组明显优于对照组(P<0.01)。结论:关节镜下应用“微骨折”技术能够显著减轻关节疼痛,增加关节活动度,改善关节功能,是一种简单有效的修复全层关节软骨缺损方法。 相似文献
59.
Carl A Kirker-Head David C Van Sickle Steve W Ek John C McCool 《Journal of orthopaedic research》2006,24(5):1095-1108
Focal full-thickness cartilage lesions of the human medial femoral condyle (MFC) can cause pain and functional impairment. Affected middle-aged patients respond unpredictably to existing treatments and knee arthroplasty may be required, prompting risk of revision. This study assesses the safety of, and biological and functional response to, a metallic resurfacing implant which may delay or obviate the need for traditional arthroplasty. The anatomic contour of the surgically exposed MFC of six adult goats was digitally mapped and an 11 mm diameter full-thickness osteochondral defect was created. An anchor-based Co-Cr resurfacing implant, matching the mapped articular contour, was implanted. Each goat's contralateral unoperated femorotibial joint was used as a control. Postoperative outcome was assessed by lameness examination, radiography, arthroscopy, synoviocentesis, necropsy, and histology up to 26 (n = 3) or 52 (n = 3) weeks. By postoperative week (POW) 4, goats demonstrated normal range of motion, no joint effusion, and only mild lameness in the operated limb. By POW 26 the animals were sound with only occasional very mild lameness. Arthroscopy at POW 14 revealed moderate synovial inflammation and a chondral membrane extending centrally across the implant surface. Radiographs at POWs 14 to 52 implied implant stability in the operated joints, as well as subchondral bone remodeling and mild exostosis formation in the operated and contralateral unoperated joints of some goats. By POW 26, histology revealed new trabecular bone abutting the implant. At POWs 26 and 52 MFC cartilage was metachromatic and intact in the operated and unoperated femorotibial joints. Proximal tibiae of some operated and unoperated limbs demonstrated limited subchondral bone remodeling and foci of articular cartilage fibrillation and thinning. The chondral membrane crossing the prosthesis possessed a metachromatic matrix containing singular and clustered chondrocytes. Our data imply the safety, biocompatibility, and functionality of the implant. Focal articular damage was documented in the operated joints at POWs 26 and 52, but lesions were much reduced over those previously reported in untreated defects. Expanded animal or preclinical human studies are justified. 相似文献
60.
Repair of large midline incisional hernias with polypropylene mesh: Comparison of three operative techniques 总被引:9,自引:0,他引:9
de Vries Reilingh TS van Geldere D Langenhorst BLAM de Jong D van der Wilt GJ van Goor H Bleichrodt RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique. 相似文献