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121.
纪悦 《基层医学论坛》2006,10(5):399-400
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   
122.
低剂量他克莫司治疗大鼠急性脊髓损伤的实验研究   总被引:2,自引:1,他引:1  
目的:探讨低剂量他克莫司(tacrolimus,又名FK506)对大鼠急性脊髓损伤是否具有神经保护作用。方法:雄性Wistar大鼠72只,随机分为假手术组(12只)、损伤组(30只)和FK506治疗组(30只)。采用Allen’s打击法致伤大鼠T10脊髓,假手术组仅做椎板切除术。FK506治疗组在脊髓损伤后5min一次性经尾静脉注射FK5060.3mg/kg,其余两组以相同方法给予等量生理盐水。致伤后30min、6h、24h、48h、72h取伤段脊髓组织行病理观察及原位末端标记法(TUNEL)检测神经细胞凋亡,伤后1、3、7、14、21d行脊髓功能BBB评分和斜板实验。结果:伤后3、7、14、21d,FK506治疗组斜板实验和BBB评分明显优于损伤组,两组间比较差异有显著性(P〈0.05);伤后各时间点FK506治疗组脊髓损伤区出血坏死较损伤组轻;伤后6、24、48、72h神经细胞凋亡FK506治疗组较损伤组明显减少,两组间比较差异有显著性(P〈0.05)。结论:在大鼠急性脊髓损伤后早期应用低剂量他克莫司(0.3mg/kg)治疗对神经具有保护作用,可减少神经细胞凋亡,减轻脊髓继发性损伤,促进脊髓功能恢复。  相似文献   
123.
颈椎病伴椎管狭窄患者再手术问题探讨   总被引:1,自引:0,他引:1  
目的:探讨颈椎病伴椎管狭窄患者再手术的原因、手术方式及其相关问题。方法:我院2002年7月~2003年12月对40例颈椎病伴椎管狭窄术后疗效不佳或症状复发的患者进行了后路多节段(5个或以上)减压手术。根据其手术治疗方式及影像学资料分析再手术原因,并进行术后疗效评价。结果:经前路手术者再手术的主要原因为:(1)伴有多节段颈椎管狭窄因素时,只选择部分压迫重的节段行减压融合15例;(2)经前路多节段(≥3个节段)减压融合后,相邻节段继续退变,出现新的脊髓压迫表现及椎间不稳定9例;(3)伴有OPLL时,行部分节段前路减压融合后,病变呈进展表现,产生或加重对脊髓的压迫8例。经后路手术者再手术的原因为:(1)后路减压节段不够5例(包括1例前后路联合手术者);(2)后路减压不充分3例。再手术后随访1.3~2.7年,平均2.1年,所有患者脊髓功能获得一定的提高,JOA评分改善率为51.3%。结论:颈椎病伴椎管狭窄病例再手术的主要原因为椎管狭窄因素仍然存在,经后路多节段(5个或以上)减压手术治疗可彻底去除颈椎管狭窄因素,有效解除脊髓前、后方所受的压迫,可获得较满意的临床疗效。  相似文献   
124.
Intracranial Angioplasty and Stenting in the Awake Patient   总被引:1,自引:0,他引:1  
BACKGROUND AND PURPOSE: Endovascular treatment for intracranial atherosclerosis is evolving, but complications remain an issue. Most interventions are performed under general anesthesia, preventing intraprocedural clinical evaluations. We describe our approach to intracranial angioplasty and stenting, using local rather than general anesthesia, and intraprocedural neurological assessment. METHODS: We prospectively collected procedural and outcome information on all patients undergoing intracranial angioplasty and stenting. Patients underwent interventions under local anesthesia with mild intravenous sedation or analgesia only if needed. Intraoperative neurological evaluations were performed, and symptomatology was used to guide the interventional technique. RESULTS: Forty-eight arteries in 40 patients with a mean age of 65.2 years were treated. Thirty-two anterior and 16 posterior circulation segments were treated. Technical success was achieved in 100% of patients with reduction of the mean pretreatment stenosis from 85 +/- 8.6% to 7 +/- 10.1%. Stents were deployed in 40 segments; five patients were treated with drug-eluting stents. The cobalt-chromium coronary stents were the easiest to deliver. Thirty-seven patients were treated under local anesthesia and, of those, 61.4% experienced intraprocedural symptoms that led to some alteration of the interventional technique. Headache was the most common symptom, and, when persistent, it heralded the occurrence of subarachnoid hemorrhage. There were seven total neurological complications, but only five (10.5%) led to permanent morbidity (4 strokes) or mortality (1 death). CONCLUSIONS: Intracranial angioplasty and stenting can be successfully performed using coronary techniques and equipment including drug-eluting stents. Local anesthesia permits neurological evaluations and often leads to the adjustment of the interventional technique, potentially making the procedure safer.  相似文献   
125.
脊髓海绵状血管瘤的诊治特点   总被引:3,自引:1,他引:2  
目的:探讨脊髓海绵状血管瘤的诊治方法和特点,方法:1991-2001年治疗脊髓海绵状血管瘤22例,均进行MRI检查,16例行全脊髓血管造影,全组均经后背正中直切口显微手术治疗,结果:22例均为单发,1例术前未能明确诊断,术后证实为海绵状血管瘤,颈段8例,颈胸段6例,胸段4例,腰段2例,圆锥马尾部位2例。MR1显示团块状短T1长T2信号,中间由点条状长T1短T2信号分隔,形成桑葚状混杂信号团,周边绕以低信号团,尤以T2WI显著,随访3个月-2年,全组均未见复发,12例术后功能明显恢复。结论:MRI是脊髓海绵状血管瘤前最可靠的诊断方法。全脊髓血管造影可以排除其它脊髓血管畸形,显微手术切除是脊髓海绵状血管瘤的优选治疗方法,术中精细的显微操作是手术成功的关键。  相似文献   
126.
目的探讨分期前路半椎体切除截骨后路矫形手术治疗严重先天性脊柱侧凸的临床疗效。方法严重先天性脊柱侧凸14例,男4例,女10例;年龄8~13岁,平均11.2岁。其中形成缺陷2例,分节缺陷6例,混合型6例。半椎体位于T53例,T2、T8、T10、T11、L1、L4各1例。胸弯12例,胸腰弯2例。术前冠状面Cobb角63°~95°,平均72.1°。胸椎后凸减小或前凸8例,胸腰段后凸4例。一期采用前路半椎体切除、多节段椎体间楔形截骨及分节不全松解;二期采用后路椎弓根钉棒系统三维矫形固定。前后路手术均植骨,平均截骨5.5个节段。结果一期前路术后冠状面Cobb角48°~60°,平均51.5°;矫正率19.6%~37.8%,平均28.6%。二期术后冠状面Cobb角5°~45°,平均30.5°;矫正率52.6%~87.5%,平均62.5%。8例存在胸椎后凸减小或前凸的患者均恢复生理性后凸,4例胸腰段后凸患者3例达到矢状面矫正。全部病例随访8~30个月,平均12.1个月。无断钉、断棒及明显的矫正度丢失,植骨融合良好。发生并发症2例,椎弓根钉帽松动1例,T1神经根激惹1例。结论一期前路半椎体切除、多节段椎体间楔形截骨、分节不全松解,二期后路矫形固定及前后路植骨治疗先天性脊柱侧凸能够达到较满意的矫形效果,适合于8~12岁的青春期前患者。  相似文献   
127.
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases. In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However, a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications.  相似文献   
128.
Whole-cell patch-clamp recordings (WCR) were made from sympathetic preganglionic neurons (SPN) in neonate rat spinal cord slices. SPN were identified histologically by filling them with the fluorescent dye Lucifer Yellow contained within the patch pipette solution. Current clamp recordings were obtained from SPN with a potassium based pipette solution. The cells exhibited many of the characteristic properties of SPN seen previously with intracellular recordings in both the rat and the cat. However, we found an order of magnitude increase in both cell input resistance (950 MΩ) and time constant (118 ms) over those seen with conventional recordings. We believe these values approximate better the situation in intact cells, and will have a vital bearing upon how SPN integrate inputs. We conclude that WCR in spinal cord slices provides a powerful tool for investigating the cellular properties of SPN.  相似文献   
129.
Background Although there have been reports dealing with ventricular diverticulum (VD) analyzed by cisternography and computed tomography (CT), those focusing on magnetic resonance imaging (MRI) or neuroendoscopic findings are rare. Case report We present a case of noncommunicating hydrocephalus caused by aqueductal stenosis with cystic lesion located in supracerebellar region. Third ventriculostomy was performed on this case. The conventional CT and MRI were compatible with usual VD, but neuroendoscopic examination suggested otherwise. The endoscopic view inside of the cystic lesion demonstrated passing veins and no membrane. We diagnosed this cystic lesion as a unique subtype of advanced VD mimicking spontaneous ventriculostomy. Endoscopic observation of the cyst was very useful for accurate diagnosis and safe treatment.  相似文献   
130.
支架术治疗颈动脉狭窄的临床研究   总被引:11,自引:1,他引:10  
目的 观察支架术治疗颈动脉狭窄的近期疗效 ,探讨临床应用中的相关问题。方法 将临床经颈部B超、脑血管造影确诊的颈动脉狭窄患者 10 8例 ,实施颈动脉支架术 ,15例行预扩张 ,12例后扩张成形 ,9例使用滤器装置 ,围手术期给予抗血小板聚集等治疗。结果  2例手术失败 ;术后 2例发生脑出血 ,1例脑栓塞 ,1例支架内血栓形成 ,除 1例脑出血死亡外 ,3例治疗后恢复 ;1~ 6个月的随访中 ,10 5例患者无复发。手术并发症发生率低 ,近期疗效满意。结论 颈动脉狭窄段支架术治疗颈动脉狭窄具有可行性 ,近期疗效肯定 ,是临床上有推广潜力的治疗颈动脉狭窄的方法 ,但远期疗效尚需进一步观察。  相似文献   
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