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991.
We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength.  相似文献   
992.
上肢屈曲性旋转撕脱离断伤的形成及功能挽救   总被引:1,自引:0,他引:1  
目的探讨上肢轴向屈曲性旋转撕脱离断伤的形成以及侧胸和背部组织在功能挽救中的应用方式和疗效。方法2000年7月~2003年9月共收治6例上肢轴向屈曲性旋转撕脱离断伤患者,所有病例行一期再植或寄养再植。术后肩关节外展90°、肘关节屈曲100°位石膏或支具固定,6周后去除固定行功能锻炼。结果6例患者再植均顺利成活,随访3个月~2年,术后肩关节外展50°~90°,前屈50°~70°,后伸20°~30°,内收20°~40°;肘关节屈曲100°~140°,伸-20°~0°;重建术后3个月时屈肘肌力达Ⅳ~Ⅴ级。结论充分利用侧胸和背部组织特点进行分期、分层手术,解决创面覆盖和功能重建互相干扰的矛盾,是挽救严重轴向屈曲性旋转撕脱离断伤上肢,恢复其外形和功能的可靠方法。  相似文献   
993.
[目的]对腰椎完整标本、单纯腰椎前路椎间融合术(ALIF)、ALIF分别行椎弓根钉固定及经椎板关节突螺钉固定4种状态进行测试,比较生物力学稳定性。[方法]采用新鲜腰椎标本8具,分别于完整状态、L5S1前路植以Cage、L5S1前路Cage分别行椎弓根钉固定及经椎板关节突螺钉固定下,测定前屈、后伸、侧弯及扭转运动下运动范围并进行比较。[结果]单纯ALIF标本同完整标本相比,其后伸运动范围增大(P〈0.01),而前屈、侧弯、扭转运动范围减小(P〈0.01);而ALIF经椎弓根钉固定或经椎板关节突螺钉固定后各方向运动范围均小于完整标本及单纯ALIF标本(P〈0.01)。[结论]L5S1单纯行ALIF后伸稳定性差,为增加其稳定性,经椎板关节突螺钉应当是首选的内固定器械。  相似文献   
994.
[目的]评价TSRH钩钉系统对青年患者腰椎弓崩裂直接修复后固定的临床疗效。[方法]自2001年7月~2003年10月,对12例男性单纯腰椎弓崩裂患者(16~31周岁)行腰椎弓崩裂自体骨直接修复峡部裂后TSRH椎板钩、椎弓根钉固定术。术后随访,根据术后X线、CT结果评价修复效果,并根据MacNab's标准进行临床评价。[结果]经过6~19个月随访,所有患者腰椎弓崩裂影像学全部融合;临床下腰痛显著缓解,按MacNab's标准,优8例,良3例,一般1例;无手术及内固定相关并发症发生。[结论]直接修复后TSRH钩钉系统固定治疗青年性腰椎弓崩裂能充分保留腰椎运动节段,在减少融合节段的同时能有效恢复腰椎稳定,操作简便、安全,固定可靠,是一种合乎逻辑的治疗青年性腰椎弓崩裂方法。  相似文献   
995.
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero.  相似文献   
996.
Objective To investigate the correlation between α1-adrenergic receptor and the pathological behavior of cholangiocarcinoma, and the effects of norepinephrine (NE) on the proliferation of cholangiocarcinoma cell line QBC939. Methods Thirty-six samples of cholangiocarcinoma were resected in Southwest Hospital from August 2002 to March 2008. The expression of α1-adrenergic receptor in the 36 samples of cholangiocarcinoma tissue and 4 samples of normal bile duct tissue were detected by SABC technique. The proliferation of cholangio-carcinoma cell line QBC939 was detected after processing the cells with NE, phentolamine and prazosin. All the data were analyzed by chi-square test. Results The high positive expression rate of α1-adrenergic receptor was 68% (17/25) in patients with lymph node metastasis, which was significantly higher than 9% (1/11) in patients without lymph node metastasis (χ2=10.604, P<0.05). The high positive expression rate of α1-adrenergic receptor was 85% (11/13) in patients with middle and low positioned cholangiocarcinoma, which was significantly higher than 30% (7/23) in patients with hilar cholangiocarcinoma (χ2=9.753, P<0.05). NE promoted the proliferation of cholangiocarcinoma cell line QBC939 by stimulating the expression of α1-adrenergic receptor, and in a concentration-dependent manner. The proliferative effect was weakened as time passed by, and it was eliminated by phentolamine and prazosin. Conclusions The expression of α1-adrenergic receptor is diverse due to lymph node metastasis and the location of the tumor, α1-adrenergic receptor with high expression may play an important role in the proliferation and metastasis of cholangiocarcinoma.  相似文献   
997.
新基因Tctex5在雄鼠生殖细胞中的表达   总被引:1,自引:0,他引:1  
目的探讨雄鼠生殖细胞中是否有Tctex5基因的表达。方法从三株体外培养的雄鼠生殖细胞CRL-1715、CRL-2053和CRL-2196细胞株中提取总RNA和蛋白,采用RT-PCR和Western blot分别从mRNA和蛋白质水平分析基因产物的表达。结果Tctex5基因在CRL-1715、CRL-2053、CRL-2196三株细胞中都有高表达。结论Tctex5基因作为一个未知功能的基因,在雄鼠生殖细胞中有丰富的表达,可能参与了精子发生的功能调节,作为男性正常生育的。个新的标志物,它可能在精子发生中扮演了一个重要的角色,该基因在雄性生殖细胞中的发现可能会对男性不育的诊断与治疗提供新的途径。  相似文献   
998.
采用正交信号校正法(OSC)对茶叶的近红外光谱进行预处理,并结合偏最小二乘法(PLS)建立表没食子儿茶素没食子酸酯(epigallocatechin gallate,EGCG)含量的预测模型.PLS校正模型采纳的最佳因子数会随着OSC因子的增加而逐渐减少以达到简化模型的效果.试验以预测残差平方和(PRESS)来评价模型的整体性能,当滤除前6个OSC因子时为最佳,此时校正模型采纳的PLS因子数为5,校正肘的相关系数r2和校正标准偏差SEC分别为0.955 90和0.38279,预测时的相关系数,和预测标准偏差SEP分别为0.936 61和0.444 13.研究结果表明,应用近红外光谱法结合0SC/PLS可以快速准确地测定茶叶中EGCG的含量.  相似文献   
999.
2008年5月12日发生的汶川里氏8.0级地震造成37万余人受伤,近90%为肢体创伤病员。其中,10%-15%患者伴有颅面、胸腹部等处创伤。我院于2008年5月23日及28日分两批收治47名震区空运伤病员,其中骨科伤病员41例。本文针对我院接收的41例骨科伤病员的入院时病情特点、治疗措施及原则等作一简要总结。  相似文献   
1000.
目的 探讨术中磁共振(iMR)影像神经导航辅助神经外科手术的麻醉管理.方法 22例神经外科手术患者采用核磁兼容或核磁可用的麻醉材料和设备,在全身麻醉(静吸复合或全凭静脉麻醉)下行iMR影像神经导航辅助颅内肿瘤切除术,术中监测心率、有创血压、脉搏血氧饱和度、呼气末二氧化碳分压、七氟醚浓度、中心静脉压以及动脉血气.结果 22例患者肿瘤的全切率从60.0%提高到86.4%.术中患者iMR扫描次数2~5次,手术时间延长1~3 h,术中未发生与麻醉和iMR相关的并发症和意外事件.结论 在iMR影像神经导航下行颅内肿瘤切除术的围术期麻醉处理中关注iMR影像神经导航外科相关的信息、手术室应用环境、麻醉技术和药物的选择以及围术期管理对患者的安全是重要的.  相似文献   
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