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51.
目的探讨MRI在颅内血管母细胞瘤诊断中的应用价值。方法18例经手术病理证实的颅内血管母细胞瘤患者,男11例,女7例,均行MRI平扫+增强检查,分析其MRI征象。结果17例血管母细胞瘤位于后颅窝。14例表现为大囊小结节型,结节强化明显;4例表现为实质型。13例瘤内或瘤周可见血管流空信号。MRI术前诊断准确率为88.9%(16/18)。结论MRI是术前诊断血管母细胞瘤的有效检查方法。  相似文献   
52.
通用型脊柱内固定系统稳定性的生物力学评价   总被引:6,自引:0,他引:6  
目的 评价通用型脊柱内固定系统经椎弓根内固定装置的生物力学稳定性。 方法取 12具正常成人新鲜尸体T12 ~S3 节段脊柱标本 ,制成L2 3 、L4 5滑脱模型 ,测试标本在正常、滑脱、通用型脊柱内固定系统 (generalspinesystem ,GSS)与SOCON固定后、疲劳试验后、GSS与SOCON翻修后、再次疲劳试验后 6种请状况下的三维运动状况 ,比较各个工况数据的差异。 结果 L2 3 节段 ,正常状态前屈运动范围平均值为 8 3° ;制成滑脱标本后 ,运动范围平均值为 14 7° ;SOCON固定后 ,节段运动范围减至 3 0°,比正常状态的运动范围减小 ,差异有显著性意义 (P <0 0 5 ) ,说明SOCON固定后可产生明显的即刻稳定作用。疲劳试验后节段运动范围平均值为 3 6°,与正常状态比较 ,差异有显著性意义 (P <0 0 5 ) ,说明经过疲劳试验SOCON固定仍有良好的稳定作用。L4 5节段 ,正常状态前屈运动范围平均值为 8 6°;制成滑脱标本后 ,运动范围平均值为 13 7° ;GSS固定后 ,节段运动范围减至 3 2°,该节段的稳定性得到加强 ,运动范围比正常状态时还要小 ,差异有显著性意义 (P <0 0 5 ) ,说明GSS固定后可产生明显的即刻稳定作用。疲劳试验后节段运动范围平均值为 3 7°。与正常状态比较 ,差异有显著性意义 (P 相似文献   
53.
目的 分析先天性脊柱侧凸患者背部中线处皮肤病变及其临床意义.方法 回顾性分析在我院初次诊治、存在背部中线处皮肤病变的先天性脊柱侧凸,除外脊髓脊膜膨出患者.结果 在1990年~2005年诊治的先天性脊柱侧凸患者中,63例患者存在背部中线处皮肤病变,具体表现为背部异常毛发32例,皮肤色素斑22例,背部软组织包块3例,背部皮肤凹陷1例,色素斑和异常毛发3例,异常毛发和皮下结节2例.13例(20.6%)患者同时存在椎管内异常,包括脊髓纵裂10例,脊髓空洞症2例,脂肪瘤1例.13例患者中,先天性脊柱侧凸类型表现为形成障碍3例,分节障碍2例,混合型8例,84.6%(11/13)为多发椎体畸形.此13例患者的皮肤异常具体表现为多毛7例,色素斑3例,背部肿物2例,皮肤凹陷1例,不同皮肤异常类型之间椎管内异常的发生率比较无统计学意义.同期诊治无背部皮肤病变的先天性脊柱侧凸294.例,11例(3.7%)存在椎管内异常,其发生率同存在皮肤病变的患者相比,差异存在统计学意义(P=0.000).结论 背部中线处皮肤病变可能是先天性脊柱侧凸患者尤其是合并多发椎体畸形者合并椎管内异常的一个标志.  相似文献   
54.
55.
OBJECTIVE: We investigated outcomes after surgical therapy in patients with active infective endocarditis (AIE) with regard to survival in relation to surgical urgency, valve position, number of valves implanted and abscess formation. We aimed to identify independent risk factors for early mortality. METHODS AND RESULTS: Two hundred and fifty-five patients received Shelhigh bioprostheses between February 2000 and March 2007. A total of 74.1% had native and 25.9% prosthetic AIE. Surgery was regarded as urgent in 57.3% and as an emergency procedure in 38.4%. There was a highly significant difference in survival rate between patients who were operated on urgently versus in an emergency (p<0.0001), between single and double valve replacement (p=0.0206) and between patients with and without abscess formation (p=0.0245). There were two cases of early reinfection (0.78%) and six of late reinfection (2.35%) leading to re-operation. CONCLUSIONS: The survival of patients differs significantly in dependence on their surgical urgency. Better outcome could have been achieved if patients had been referred earlier for surgery and operated upon before heart failure or septic shock developed. Long-term survival was better in patients without abscess formation. The low reinfection rate of Shelhigh bioprostheses in AIE is promising and the early and mid-term results achieved need to be verified in the long-term course.  相似文献   
56.

Background  

In idiopathic scoliosis patients, after anterior spinal fusion and instrumentation, the discs (interspace angle) between the lowest instrumented vertebra (LIV) and the next caudal vertebra became more wedged. We reviewed these patients and analyzed the changes of the angle.  相似文献   
57.
硅胶薄膜囊预防椎体后凸成形术中骨水泥渗漏的实验研究   总被引:1,自引:1,他引:1  
目的探讨硅胶薄膜囊预防椎体后凸成形术中骨水泥渗漏的可能性和有效性。方法取6具甲醛固定的老年女性脊柱标本(T12~L5)制成36个单椎体,刮匙在椎体前3/4制成体积约为6ml单侧或双侧空腔,分别直接注入骨水泥和先置入壁厚100μm、200μm的硅胶薄膜囊后再注入骨水泥。结果壁厚100μm的硅胶薄膜囊包裹骨水泥可控制骨水泥在椎体内的分布,和直接注入骨水泥一样能较好地嵌入到周围骨小梁内,不形成界面。而壁厚200μm的硅胶囊虽能控制骨水泥在椎体内分布,但会在骨小梁间形成界面。结论球囊扩张椎体后凸成形术中置入壁厚100μm的硅胶薄膜囊包裹骨水泥可控制椎体内骨水泥分布,并能嵌入到骨小梁间隙,不形成界面,有效预防球囊扩张椎体后凸成形术并发症的出现。  相似文献   
58.
"分段切开,多重挂线术"治疗高位复杂性肛瘘临床研究   总被引:4,自引:0,他引:4  
目的:观察"分段切开,多重挂线术"治疗高位复杂性肛瘘的临床疗效。方法:将60例高位复杂性肛瘘随机分为治疗组40例,采用"分段切开,多重挂线术";对照组20例,采用传统切开挂线术进行对比观察。结果:显示治疗组与对照组显愈率分别为95%和90%,无明显差异(P>0.05),但两组间的术后疼痛程度、创口愈合时间、肛门功能情况存在显著差异(P<0.05)。结论:在治疗高位复杂性肛瘘时,"分段切开,多重挂线术"与传统切开挂线术相比,具有手术操作简单,对组织损伤小,痛苦小、疗程短、肛门功能保护好等优点,该术式的应用,使得高位复杂性肛瘘治疗更加安全、有效。  相似文献   
59.
BACKGROUND: Until recently, there has been no practical alternative to the use of calcineurin inhibitors (CIs) as primary immunosuppressants in lung transplantation (LTx) and heart transplantation (HTx). Sirolimus (SRL) is a novel powerful immunosuppressant without renal toxicity, a common post-transplant problem associated with CI therapy. METHODS: SRL was used in 20 LTx and 5 HTx recipients >90 days post-transplant, where serious renal impairment was limiting CI dosing. Patients started on 2 to 5 mg/day orally at a median of 1,185 days post-transplant. Dosage adjustments were made according to trough levels, toxicity and perceived efficacy. With SRL initiation, 48% ceased CI therapy and the remainder decreased their dose substantively. RESULTS: After 30 days, 4 of 5 dialyzed patients ceased dialysis and 15 of 20 patients with an elevated serum creatinine (Cr) (mean Cr 0.29 mmol/liter) improved their Cr. The direction of change in Cr at 30 days predicted longer term Cr. The starting Cr did not predict the 30-day or long-term value. There were two bouts of acute and one bout of chronic rejection. There were 35 infectious complications in 16 patients and 24 episodes of potential SRL-related toxicity in 17 patients. These events generally responded to dose reduction or temporary cessation and were level-related. Fifteen recipients presently remain on the drug. None of the 7 deaths could be directly related to toxicity. CONCLUSION: SRL is a useful alternative immunosuppressant, allowing significant CI withdrawal in transplant recipients with renal impairment. Whether the resulting improvement in Cr can be maintained in the long term probably depends on the balance between the extent of acute and chronic renal damage.  相似文献   
60.
The clinical significance of pre-transplant donor-specific antibodies (DSA), despite negative cytotoxicity and flow cytometry crossmatches (FCXMs), is unknown. We performed a retrospective cohort study of 60 living donor renal transplant recipients, all with pre-transplant cytotoxicity and T-cell and B-cell FCXMs that were negative. Twenty recipients had pre-transplant DSA detected by enzyme-linked immunosorbent assays (ELISA) and/or microbead methods. Forty contemporaneous DSA-negative controls were selected. In the DSA-positive group, after a median follow-up of 8.2 months (25-75% range, 5.4-22.8 months), patient survival was 100% and allograft survival was 95.0%. Acute humoral rejection (AHR) developed in four patients (20.0%). Three of the AHR episodes occurred within the first month post-transplant. Median serum creatinine at last follow-up was 1.3 mg/dL (25-75% range, 1.0-1.6 mg/dL), versus 1.1 mg/dL (25-75% range, 0.9-1.4 mg/dL) in the DSA-negative controls (p = 0.29). Only one of the 40 controls developed AHR (2.5%). Pre-transplant DSA was associated with a significantly increased incidence of AHR (p = 0.02 by log-rank test). In conclusion, despite negative pre-transplant cytotoxicity and FCXMs, renal transplant recipients with pre-transplant DSA detected by solid-phase methods may have an increased incidence of AHR and require close monitoring post-transplant.  相似文献   
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