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1.
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively or on histological examination. We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was immune competent and had no past history of sinusitis. The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype of invasive fungal sinusitis and the degree of tissue invasion.  相似文献   
2.
应用标准微电极技术,研究了关附甲素对豚鼠右心室乳头肌动作电位最大除极速率(Vmax)的频率依赖性抑制作用(RDB),并与美西律,奎尼丁,劳卡尼进行了比较. 在相同刺激间隔(300 ms),产生50%左右RDB的药物浓度下,美西律的RDB开始最快,其第2个Vmax所产生的抑制已占RDB的64%,奎尼丁,劳卡尼和关附甲素的RDB开始速率常数分别为每个动作电位0.165, 0.076和0.136. 美西律,奎尼丁,劳卡尼和关附甲素产生RDB的恢复时间常数分别为1.4, 9.0, 18.2和44.0 s,而且它们的恢复时间常数是不依赖于药物浓度而变化的,结果提示,关附甲素是一个慢动力学钠通道阻滞剂.  相似文献   
3.
目的:为了更完全地切除中颅凹底内外沟通性肿瘤。方法:采用经过改良的Mickey额颞颞下窝入路。其改良主要是将额骨瓣连同其表面附着的颞肌以及游离后的眶颧骨块一并向下翻开,并将手术程序作了相应改变。结果:成功切除了13例肿瘤。术后3例恢复了轻工作,6例能自主生活,3例生活仍需别人照顾,1例复发未再次手术。结论:采用改良的额颞颞下窝入路对中颅凹底内外沟通性肿瘤暴露充分,切除广泛。Mickey入路改良的优点:颞肌血运的保留,有利于骨瓣与正常颅骨的早期融合。同时颞肌附着点的保留,有利于咀嚼功能。  相似文献   
4.
5.
义齿PMMA基托表面粗糙度影响的实验研究   总被引:2,自引:0,他引:2  
目的:研究技工操作因素对义齿树脂基托表面粗糙度的影响。方法:在不同粉液比、充填时期、聚合温度、混合方式以及出盒温度成型的上颌半口义齿基托上选取1.5cm^2范围,按照统一的打磨顺序,由粗到细打磨抛光完成,浸入冷水中,7天后进行粗糙度测试,所得数据经t检验统计处理。结果:在单体含量降低组、丝状期充填组.热处理时直接放入70℃水中维持9h组与对照组相比,均存在显著差异(P〈0.05)。结论:影响PMMA树脂表面粗糙度的制作工艺因素有单体含量降低、丝状期充填和未经100℃高温热处理。  相似文献   
6.
Summary A retrospective study of 61 patients with glomus jugulare tumours treated at the National Hospital for Neurology and Neurosurgery, and at the Royal National Throat, Nose and Ear Hospital, London. The average age at presentation was 41.7 years. The patients were mainly treated by a posterolateral combined otoneurosurgical approach. 42/61 of the patients had total or subtotal excision of their tumours, 7/61 had partial removal and the remaining 11/61 had no operation. Only one case required a 2-staged procedure. There were two deaths in the postoperative period, one from intracerebral haemorrhage and the other from the left hemisphere infarction.Postoperative radiotherapy was given to 5/7 of the patients who had partial removal. 3/40 of the patients with total removal had postoperative radiotherapy, and a further 3/40 had received radiotherapy pre-operatively.Of the 11 patients who did not undergo surgery, 7/11 were treated with radiotherapy and 4/11 had embolisation only.  相似文献   
7.
The purpose of this paper is to detail the contraindications for surgery, with curative intent for those patients who suffer from a head and neck malignancy that invades the intracranial space. This is based on a 30-year experience of over 250 patients. The most important contraindications are anatomical. Surgery is not done if the following structures are invaded: brain stem, eloquent portions of the cerebrum, superior sagittal sinus, both internal carotid arteries, both cavernous sinuses and certain vital bridging veins. Certain tumor factors are absolute but are occasionally relative contraindications: such as distant metastatic disease especially if multiple and at multiple anatomic sites. Some tumors that behave in a particularly virulent fashion that defy complete resection but are often difficult to predict preoperatively. Lack of patient medical fitness or absence of patient commitment to the operative procedure is make-up two serious contraindications to surgery. Presented at the 77th Annual Meeting of the German Society for Oto-Rhino-Laryngology, Head and Neck Surgery, 24–28 May 2006, Mannheim, Germany.  相似文献   
8.
Background : Osseous cranial base tumours in children present as a diverse collection of both benign and malignant pathologies. Concerns raised by the difficulty in accurate diagnosis and local recurrence of benign lesions and by the long-term sequelae of radiotherapy for malignant cranial tumours (marked local growth disturbances, pituitary dysfunction, visual disturbances, late new tumour induction) prompted an evaluation of surgical resection of cranial base tumours in children, with specific regard to safety, efficacy and aesthetic result. Methods : A retrospective review was performed of 10 consecutive children presenting with tumours either arising from or eroding into bone of the cranial base who were managed by surgical resection in a 10-year period from 1986 to 1996. The patients demonstrated a great variation in both presentation and pathology. All underwent surgical resection of tumour with reconstruction where indicated. Results : There were no postoperative complications or mortality. All patients remained clinically free of disease at follow-up, which ranged from 17 months to 9 years (mean 6 years and 4 months). Conclusion : The aggressive surgical resection and craniofacial reconstruction of cranial base tumours in the paediatric population offers a safe and efficacious mode of treatment that obviates problems of diagnosis and local recurrence for benign lesions and of the long-term sequelae of radiotherapy for malignant lesions.  相似文献   
9.
[目的]探讨切除侵犯中颅窝的咽旁颞下区巨大肿瘤安全而彻底的手术进路.利用颞部切口可充分暴露中颅窝底和颞下窝以及颌下进路显露咽旁区解剖的特点,联合进路切除2例咽旁颞下区巨大肿瘤.2例侵犯中颅窝底的咽旁颞下区肿瘤顺利切除,患者术中组织损伤、出血量相对较少,术后无严重并发症.[结论]颞部-颌下联合进路适合于侵犯中颅窝底的咽旁颞下区肿瘤的手术切除.  相似文献   
10.
在线考试系统设计   总被引:1,自引:0,他引:1  
作为评价网络学习效果的一个环节,网上考试越来越被人们接受和认同。文章介绍了在线考试系统的功能和结构,并对该考试系统中所用到的关键技术进行了详细的介绍,包括系统的通用性和安全性、题库的建设和管理、随机组卷算法等。  相似文献   
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