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81.
目的 通过计算机辅助设计有限元分析,找寻髋臼内壁截骨的合适内移范围,为临床工作提供理论依据.方法 利用SolidWorks 2005软件,建立髋臼发育不良骨盆的三维模型,模拟髋臼内壁内移截骨术式,使髋臼内壁骨从未完全陷入盆腔内保持2 mm骨性接触处开始,逐渐内移至完全陷入盆腔内7 mm处,每隔1 mm为1个实验组,分成10个实验组.每组髋臼人为划成4个象限,分别对各组假体臼-骨界面间进行计算机模拟对比力学实验分析,测量出髋臼假体-骨界面间的Mises应力及剪切应力值,找寻出应力分布较为均匀的实验组.结果 Mises应力及剪切应力均有1个象限内的值较大,通过2次统计学分析计算,得出实验结果.结论 当髋臼内壁内移至未完全陷入盆腔内1 mm处到完全陷入盆腔内1 mm处的范围内,髋臼假体-骨界面间的应力分布均匀,最佳位置在完全陷入盆腔内1 mm处.  相似文献   
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The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction.  相似文献   
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双J管临床应用及美蓝在置管术中的作用   总被引:1,自引:0,他引:1  
目的探讨双J管(双J输尿管支架管)在泌尿系疾病治疗中的应用效果以及美蓝在置放术中的作用。方法对215例患者采用放置双J管作内支架和内引流治疗,近期48例术中以美蓝协助定位。结果术后留置尿管5~7d,无切口感染、尿瘘等并发症。术后1~3个月拔除双J管,随访3~6个月,肾功能、肾积水明显好转,吻合口通畅。以美蓝协助定位者无双J管上移致拔管困难。结论双J管具有内支架和内引流作用,操作简单,引流效果好,并发症少,缩短住院时间。以美蓝协助定位,值得推广应用。  相似文献   
87.
不同临床和病理分型对肝门部胆管癌切除术预后的影响   总被引:2,自引:0,他引:2  
目的 研究临床和病理分型与肝门部胆管癌切除术疗效的关系。方法总结1993年至2004年在解放军总医院肝胆外科手术切除的肝门部胆管癌198例病例资料。结果临床分型Ⅰ型34例,Ⅱ型60例,Ⅲa型27例,Ⅲb型33例,Ⅳ型19例,Ⅴa型6例。Ⅴb型19例。病理高分化腺癌35例,中分化腺癌52例,低分化腺癌54例,三者的中位生存期分别为29.5、11、5.5个月;病理切缘阴性者与切缘阳性者生存率有显著性差异(P 〈0.05)。手术并发症出现率41.4%,围手术期死亡1例。结论肝门部胆管癌根据临床分型进行相应的手术治疗;病理切缘阴性是影响预后的主要因素之一;围手术期正确处理,是减少手术并发症,提高患者生活质量和延长生存期的关键。  相似文献   
88.
The structures of the developing eye-stalk and the relationships of early retinofugal fibers as they pass through the stalk, chiasm, and tract have been studied by light and electron microscopical methods in fetal ferrets aged 23–27 days. The early eye-stalk can be divided into two parts: a narrow extracranial part has a narrow lumen and is lined by few cells, whereas a thicker intracranial part has a wider lumen and is lined by several rows of cells. At the earliest stages no axon bundles are recognizable in the stalk, but fibers of the supraoptic commissure are already beginning to cross the midline in the diencephalon. Subsequently, as retinofugal axons invade the stalk, the glia of the extracranial part of the stalk have an interfascicular distribution and axon bundles are separately encircled by glial cytoplasm. In the intracranial part, as in the chiasm and tract, the glial cells occupy a periventricular position and send slender radial cytoplasmic processes to the subpial surface; these pass between groups of axons that here lie immediately deep to the subpial glia. Whereas axonal growth cones have no evident preferred distribution in the extracranial stalk, they tend to accumulate near the pial surface intracranially. The boundary between the two types of organization shifts as development proceeds so that the interfascicular glial structure of the early extracranial stalk first encroaches upon the intracranial parts and later appears in the chiasm. The characteristic adult arrangement of fibers in an age-related order in the optic chiasm and tract, but not in the optic nerve, can be understood if axonal growth cones are guided toward the pial surface by radial glia but not by interfascicular glia. From the distribution of the growth cones, this is what appears to happen.  相似文献   
89.
OBJECTIVES: We reviewed the results of surgical treatment for children with ureterocele, especially addressing the importance of the lower urinary tract reconstruction. METHODS: We present medical records of 91 children with ureterocele (31 with the intravesical type, and 60 with the ectopic type) treated during the last 14 years. As the initial treatment, we carried out transurethral incision of the ureterocele (TUI). In patients with persistent reflux, breakthrough urinary tract infection (UTI), or signs of bladder outlet obstruction due to a collapsed cele wall, we recommended that patients undergo lower urinary tract reconstruction irrespective of the renal function involved in ureterocele. The average follow-up period was 5 years (ranging 1 year and 6 months to 14 years). RESULTS: Transurethral incision of the ureterocele was carried out as the initial treatment on 68 patients (75%). A total of 34 patients (21 intravesical [68%] and 13 ectopic [22%]) were followed medically after TUI alone. Reconstruction of the lower urinary tract was carried out in 59 patients (65%). Nephroureterectomy combined with bladder level reconstruction was carried out in four children with single system and non-functioning kidney. Follow-up voiding cystourethrography showed that only one girl had reflux, which disappeared after the first follow-up examination. Postoperative UTI occurred in 12 patients (20%) with ectopic ureterocele. Voiding dysfunction was suspected in eight patients. CONCLUSION: We believe that the primary objective for patients with ureterocele, especially of the ectopic type, is to reconstruct the original pathology of the lower urinary tract that may give rise to reflux, obstruction, or abnormalities of urination. Although surgery at the bladder level can be challenging, the lower urinary tract reconstruction successfully corrects the vesicoureteral reflux and bladder outlet pathology under a cosmetically acceptable incision.  相似文献   
90.
The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.  相似文献   
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