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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.
BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference.  相似文献   
3.
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   
4.
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   
5.
Geste antagonistes, or sensory tricks, are well described in focal dystonia affecting the neck, hand, and face. Improvement in dystonic movements is typically maintained while the trick is performed, but disappears when the geste ends. We investigated the phenomenological features of geste antagoniste maneuvers in 19 patients with idiopathic lower cranial dystonia who were prospectively evaluated over a period of 6 years. Of the 19, 10 were men, mean age of onset was 49.8 years, and the most commonly involved lower cranial area was the jaw (10 patients). In most patients, dystonia was task-specific. Taking advantage of the improvement with a sensory geste, we manufactured oral appliances that mimicked the geste in 8 patients, and 3 continue to use it.  相似文献   
6.
7.
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   
8.
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   
9.
Virtually all cell types in the inner ear develop from the cells of the otic vesicle. The otic vesicle is formed by the invagination of non-neural ectodermal cells known as the otic placode. We investigated whether a recently described cell population, originating from the ventral part of the hindbrain neural tube known as the ventrally emigrating neural tube (VENT) cells, also contributes cells to the otic vesicle. The ventral hindbrain neural tube cells were labeled with the fluorescent vital dye DiI or replication-deficient retroviruses containing the LacZ gene in chick embryos on embryonic day 2, after the emigration of neural crest from this region. One day later, the labeled cells were detected only in the hindbrain neural tube. Shortly thereafter, the labeled cells began to appear in the eighth (vestibulocochlear) cranial nerve and otic vesicle. From embryonic day 3.5-5, the labeled cells were detected in the major derivatives of the otic vesicle, i.e. the endolymphatic duct, semicircular canals, utricle, saccule, cochlea, and vestibulocochlear ganglion. That the emigrated cells originated from the ventral part of the hindbrain neural tube was confirmed by focal application of DiI impregnated filter paper and with quail chimeras. It is concluded that, in addition to the otic placode cells, the otic vesicle also contains the ventrally emigrating neural tube cells, and that both cell populations contribute to the structures and cell types in the inner ear. It is well known that inductive signals from the hindbrain are required for the morphogenesis of the inner ear. The migration of the hindbrain neural tube cells into the otic vesicle raises the possibility that the inductive effect of the hindbrain might be mediated, at least in part, by the ventrally emigrating neural tube cells and that, therefore, a mechanism exists that involves cells rather than diffusible molecules only.  相似文献   
10.
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   
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