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991.
992.
目的:总结李氏复位法、Epley法和Semont法三种手法复位治疗良性阵发性位置性眩晕(BPPV)患者的疗效。方法将2011年1月至2013年1月收治的78例BPPV患者随机分为3组,分别采用李氏法、Epley法和Sement法进行治疗,评定其疗效,随访6个月。结果三种方法治疗有效率在治疗后1、2、6个月时差异无统计学意义(P〉0.05)。患者随访6个月,均无复发。治疗过程中仅3例出现呕吐,休息后好转。结论三种方法治疗有效率相近(P〉0.05),治疗时可依据患者情况选择不同复位法。  相似文献   
993.
目的:采用三维有限元技术,分析下颌第一磨牙在(牙合)面水平磨耗与倾斜磨耗2种情况下受力时,其牙体内的应力分布和瞬间位移情况,探讨近中根纵裂发生的生物力学依据.方法:运用Mimics有限元软件建立下颌第一恒磨牙三维有限元模型,分为无磨耗组(对照组)、水平磨耗组(实验组1)和倾斜磨耗组(实验组2)3组,实验组1和实验组2再根据4种磨耗程度,分别建立平切1、平切2、平切3、平切4和斜切5°、斜切10°、斜切15°与斜切20°8种研究模型.经(牙合)面加载200 N的咬合力,运用MSC.Marc非线性有限元分析软件分析各种状态下模型内的等效应力和瞬间位移,分析牙根纵折发生的生物力学依据.结果:①无磨耗组第一磨牙应力主要集中在(牙合)面中央窝沟处,位移等值线主要集中在牙冠近中偏颊(牙合)面,向下延伸至牙颈部.②水平磨耗组应力主要集中于牙冠部及近远中根的根分叉水平,位移等值线整体逐渐偏向(牙合)面近中偏颊侧牙颈部区域,类似于楔状缺损的V型.③在倾斜磨耗组,当磨耗平面向远中倾斜角度由5°增至15°时,瞬间位移等值线与牙长轴交角变小,近中根所受剪切力最大,产生的应力集中,发生牙根纵裂的可能性增大;当倾斜角度增大至20°时,应力主要集中在牙冠部,其位移等值线呈环形,最大位移出现在牙冠内.提示临床上当牙冠磨耗严重、牙尖斜面明显倾斜时,倾斜牙尖成为应力集中区,易发生折裂.结论:下颌第一磨牙(牙合)面磨耗面向远中倾斜时,其近中根发生纵裂的可能性较大,为临床上预防性调磨过度磨耗的下颌第一磨牙,降低近中根纵裂的可能性提供了生物力学依据.  相似文献   
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PURPOSE: This study contained herein assessed long-term results, toxicity, and prognostic variables following combined modality therapy of patients with International Union Against Cancer Classification T1–4, N0–3, M0 squamous-cell carcinoma of the anal canal. PATIENTS AND METHODS: Between 1985 and 1996, 62 patients completed treatment with combined modality therapy. A median total dose of 50 Gy was given to the primary, perirectal, presacral, and inguinal nodes followed by a local boost in selected cases. 5-Fluorouracil was scheduled as a continuous infusion of 1,000 mg/m2 per 24 hours on days 1 to 5 and 29 to 33 and mitomycin C as a bolus of 10 mg/m2 on days 1 and 29. Routinely processed paraffin-embedded sections were stained using monoclonal antibodies for detection of proliferating cell nuclear antigen and MIB1 (Ki-67) antigen to determine the labeling index. In addition, DNA ploidy was assessed after Feulgen staining. RESULTS: Actuarial cancer-related survival, no evidence of disease survival, and colostomy-free survival rates at five years were 81, 76, and 86 percent, respectively. In univariate analysis, T category (T1/2 vs. T3/4) was predictive for no evidence of disease survival (87vs. 59 percent;P=0.03) and colostomy-free survival (94vs. 73 percent;P=0.05). N category (N0vs. N1–3) influenced actuarial cancer-related survival (85vs. 58 percent;P=0.002) and no evidence of disease survival (80vs. 53 percent;P=0.02). A higher proliferative potential as measured by the MIB1 labeling index was associated with a better colostomy-free survival (90vs. 50 percent;P=0.04). In multivariate analysis, actuarial cancer-related survival was only influenced by the N category (P=0.03) and no evidence of disease survival by N category (P=0.03) and mitomycin C dose (P=0.04). Salvage abdominoperineal resection achieved long-term control in only four of seven patients with local failures. CONCLUSION: Treatment with a combination of radiotherapy and chemotherapy is safe and effective for patients with anal canal carcinoma. Abdominoperineal resection is indicated as a salvage procedure in nonresponding and recurrent lesions and may be of benefit in a small subgroup of patients with poor prognostic factors.Supported by a grant from the Wilhelm Sander Foundation (Nr. 94.061.1).Presented at the European Cancer Conference (ECCO9), Hamburg, Germany, September 14 to 18, 1997.  相似文献   
999.
Abstract Background The purpose of this study was to assess the influence of the type of anaesthesia (local vs. general) and of the electrode used (test electrode vs. tined lead) on a successful screening period. Methods Between May 2001 and January 2004, we performed 25 percutaneous nerve evaluation (PNE) tests in 20 patients (11 women). The first 15 PNE tests were followed by introducing a conventional electrode, and since 2003 by a tined lead electrode. Success was defined as reduction of symptoms by more than 50%. Results A stimulator was implanted in 13 (68%) patients, including 4 of 14 screened with the conventional electrode and 9 of 10 screened with tined lead electrode (p=0.005). Eleven (44%) of the PNE tests were done under local anaesthesia, but the success rate was not influenced by the type of anaesthesia (local 46% vs. general 61%, p=0.682). Conclusions PNE testing and implantation of the tined lead electrode can be easily performed at the same time under local anaesthesia. The use of the new tined lead electrode significantly increased the success rate for the screening phase.  相似文献   
1000.
INTRODUCTION: Magnetic stimulation of the sacral nerve roots is used for neurologic examination. However, no one has reported therapeutic efficacy of pain relief from pudendal neuralgia with sacral magnetic stimulation. METHODS: Five patients with pudendal neuralgia or sciatica received 30 to 50 pulsed magnetic stimuli of the sacral nerve roots. The median age of the patients was 59 (range, 28–69) years; there were 3 females. RESULTS: Sacral magnetic stimulation immediately eliminated the pain. The pain relief lasted between 30 minutes and 56 days (median, 24 hours). Adverse effects were not observed. CONCLUSIONS: This pilot study indicates that magnetic stimulation of the sacral nerve roots may be a promising therapeutic modality for pain relief from pudendal neuralgia and sciatica. Further studies should be performed to determine the appropriate intensity and frequency, as well as the utility of a second course, of magnetic stimulation treatment.  相似文献   
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