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61.
根管预备程度对无髓牙根管壁应力影响的分析   总被引:6,自引:0,他引:6  
目的 分析不同根管腔的直径对根管壁应力的影响。方法 在已建立的下颌第一磨牙模拟常规法根管预备修改的实验模型基础上,再修改根管腔直径,使根管直径扩大到牙根直径的1/3和1/2,并在修改模型上加载,计算在不同加载条件下牙齿各部及管壁的最大应力。结果 根管腔直径增大会引起根管壁应力的升高,该变化主要出现在根管口和根上1/3段,侧向加载时产生的应力差异大于垂直加载时产生的应力差异。结论 根管预备应以去除根管壁的感染物质,获得良好的根管成形为原则,过度的预备不仅没有必要,甚至有害。  相似文献   
62.
低位直肠癌保留神经的腹膜外侧方扩大清扫的效果分析   总被引:1,自引:1,他引:0  
目的 探讨低位直肠癌保留神经的腹膜外侧方扩大清扫对患者术后生存率、排尿功能和性功能的影响。方法 回顾性分析我院1996年1月至2000年6月期间收治的392例进展期低位直肠癌实施保留神经的根治性切除术患者的临床资料,其中行腹腔内清扫173例,腹腔内加腹膜外侧方清扫219例,2组患者在年龄、性别、浸润肠壁深度及肿瘤病理组织学类型方面差异无统计学意义。结果 腹腔内加腹膜外侧方清扫组侧方淋巴结转移率为17.8%(39/219),侧方盆壁非连续性癌灶转移率为5,9%(13/219)。术后发生排尿功能障碍:腹腔内清扫组7例(4.0%),腹腔内加腹膜外侧方清扫组113例(51.6%),2组比较差异有统计学意义(P〈0.01);性功能障碍:腹腔内清扫组93例男性患者中有12例(12.9%),腹腔内加腹膜外侧方清扫组119例男性患者中有62例(52.1%),2组比较差异有统计学意义(P〈0.01);局部复发率:腹腔内清扫组为16.2%(28/173),腹腔内加腹膜外侧方清扫组为9.6%(21/219),2组比较差异有统计学意义(P〈0.05);5年生存率:腹腔内清扫组为49.1%(85/173),腹腔内加腹膜外侧方清扫组为59.4%(130/219),2组比较差异有统计学意义(P〈0.05)。结论 低位直肠癌保留神经的腹膜外侧方扩大清扫,可以减少局部复发,提高患者5年生存率,但也会影响患者术后排尿和男性性机能。  相似文献   
63.
This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.  相似文献   
64.
The use of expanded criteria donors (ECD) has been proposed to help combat the discrepancy between organ availability and need. ECD kidneys are associated with delayed graft function (DGF) and worse long-term survival. The aim of this study is to evaluate the impact of pulsatile perfusion (PP) on DGF and graft survival in transplanted ECD kidneys. From January 2000 to December 2003, 4618 ECD kidney-alone transplants were reported to the United Network for Organ Sharing. PP was performed on 912 renal allografts. The prognostic factors of DGF were analyzed using multivariate logistic regression analysis. Risk factors for reduced allograft viability were greater in donors and recipients of PP kidneys. Three-year graft survival of ECD kidneys preserved with PP was similar to cold storage (CS) kidneys. The incidence of DGF in PP kidneys was significantly lower than CS kidneys (26% vs. 36%, p < 0.001). Despite having a greater number of risk factors for reduced graft viability, the ECD-PP kidneys had similar graft survival compared to ECD-CS kidneys. The use of PP, by decreasing the incidence of DGF, may possibly lead to lower overall costs and increased utilization of donor kidneys.  相似文献   
65.
Ruptured aneurysms of the distal anterior choroidal artery (AchA) are extremely rare and management is dictated by clinical presentation. This report describes a rare patient with a distal AchA aneurysm and subarachnoid and intraventricular haemorrhage. A 60-year-old woman presented with a sudden onset of severe headache and vomiting. No aneurysms could be found on initial angiograms. A repeat angiogram performed 10 days after admission demonstrated an aneurysm in a branch of the cisternal segment of the left AchA without a definite neck. Surrounding vessels showed multifocal stricture and dilatation. Microsurgical clipping was not performed because the patient died suddenly due to pulmonary failure. The aetiology of the aneurysm in this case and surgical strategy are discussed.  相似文献   
66.
IIEF-5与NEVA检测在阴茎勃起功能障碍诊断中的意义   总被引:2,自引:2,他引:0  
目的探讨应用国际勃起功能评分5(IIEF-5)问卷表结合夜间阴茎勃起测定系统(NEVA)筛选勃起功能障碍(ED)的可行性及意义。方法148例门诊ED病人,应用IIEF-5问卷表评分,再通过NEVA测定仪监测夜间阴茎勃起情况,次日数据输入主机回放并分析。结果93例为心理性ED;在19~69岁的5个年龄组中,重度ED的比例由11.8%到55.0%,NEVA中度异常者IIEF积分(12.98±2.58)分,NEVA重度异常者IIEF积分(7.32±1.04)分。结论NEVA能有效地鉴别心理性与器质性ED,IIEF-5评分值与NEVA检测阴茎勃起时血容量变化值有相关性。IIEF-5与NEVA检测结合,能提高诊断和评估ED的可靠性。  相似文献   
67.
68.
PURPOSE: Concern over stigma as a consequence of genetic testing has grown in response to the recent increase in genetic research and testing resulting from the Human Genome Project. However, whether a genetic or hereditary basis necessarily confers a stigma to a condition remains unexamined. METHODS: We performed a qualitative interview study with 86 individuals with one of four conditions: deafness or hearing loss, breast cancer, sickle cell disease, and cystic fibrosis. The first two groups were divided approximately between people who ascribed their conditions to a genetic or hereditary cause and those who did not. RESULTS: Respondents interpreted genetic or hereditary causes and nongenetic causes in a variety of ways. Subjects with breast cancer reported the most consistently negative interpretation of genetic cause. This response concerned future ill health, not an enduring sense of stigma. Deaf and hard of hearing subjects provided the most consistently positive comments about a genetic or hereditary basis to their condition, casting familial hearing loss as a vital component of group and individual identity. Respondents with sickle cell disease and cystic fibrosis offered similar and positive interpretations of the genetic cause of their condition insofar as it meant their conditions were not contagious. CONCLUSIONS: Although some subjects report feeling stigmatized as a result of their condition, this stigmatization is not uniformly associated with the condition's cause, genetic or otherwise. Instead, stigma emerges from a variety of sources in the context of the lived experience of a particular condition.  相似文献   
69.
70.
庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响   总被引:1,自引:0,他引:1  
目的:研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及其受体(insulin-like growth factor-1 receptor,EGF-1R)表达的影响,并探讨其生物学特性。方法:采用免疫组织细胞化学方法,以抗IGF-1及IGF-1R抗体为标记物,检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点;采用Brdu体内标记和抗Brdu抗体免疫组化染色,检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果:IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达,庆大霉素损伤后,其表达增多。在1d组IGF-1及IGF-1R表达最强,其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞,7d组最多。结论:庆大霉素损伤后,豚鼠前庭上皮IGF-1及IGF-1R表达增强,其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。  相似文献   
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