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1.
Objective Teratoma is the most frequently encountered intracranial tumor at birth and constitutes 18–20% of all germ cell tumors. They are usually located in pineal and suprasellar regions. The authors aim to report an extremely unusual presentation, location, and appearance of a teratoma in a newborn. Case report A soft tissue swelling in the vertex was detected in a 1-month-old girl. Neurological examination was normal. A big, cystic–solid lesion beginning from pineal region and extending to the scalp was detected in magnetic resonance imaging. It is interesting to note that cerebral venous angiography showed that the superior sagittal sinus (SSS) was divided into three branches at the level of the lesion and they joined together distally. The tumor was excised totally. Histopathological examination revealed the diagnosis of a mature cystic teratoma. Conclusion A mature cystic teratoma mimicking parietal encephalocele is extremely rare. Germ cell tumors should be kept in mind in the differential diagnosis of all midline lesions with unusual radiographic appearance. Cerebral venous angiography or MR angiography must be performed for the diagnosis and the surgical planning in lesions located near SSS.  相似文献   
2.
A neonate with severe respiratory distress due to a benign mediastinal teratoma (MT) is reported. Despite early and easy surgical excision of the tumor, the child died due to poor cardiac function. Only ten cases of MT in neonates have been reported in the literature so far. While the tumor has been known to interfere with lung development in utero, postnatal myocardial dysfunction due to poor heart development has not been previously documented. Accepted: 22 September 1997  相似文献   
3.
目的:探讨人类恶性畸胎瘤PA-1细胞株染色体特性及其影响因素。方法:采用G带核型分析、DNA碱基序列分析及Western blot(蛋白印迹分析)等方法对经20余年407-445继代培养的PA-1细胞株染色体核型及p 53 基因状态进行了研究。结果:PA-1细胞株80%以上仍然保持近乎二倍体的核型,30代以后的细胞由于第15号染色体与20号染色体间的相互易位形成了M1及M2标识染色体。RT-PCR产物DNA定向序列分析显示具有野生及突变两个带(p53密码子239突变),Western blot 未检测出突变的p53基因蛋白,而p21蛋白的表达水平比正常成纤维细胞低。结论:人卵巢恶性畸胎瘤PA-1细胞株经20年的继代培养后,一个p53 等位基因发生错义突变,另一个仍然是野生型的。仅一个p53 等位基因发生突变,不足以引起细胞的染色体不稳定性。  相似文献   
4.
Summary A congenital human teratoma contained a neuroectodermal mass with architectonic features similar to those of the normal developing neo-cortex. Surrounding a central cavity, a germinal, an intermediate and a cortical zone were clearly distinguishable from innermost to outermost. Glial fibers coursed radially through the intermediate and cortical zones. In the cortical plate neuronal elements were oriented radially with an inside out gradient of differentiation. Mesothelial tissue covered the outer surfaces of the cortex. Over limited sectors a gap in the integrity of the meso-glial barrier were associated with neuroglial ectopias.The following points are of neurobiologic importance: the formation of the miniature cerebral cortex occurred in the absence of any influence of afferent subcortical fibers. The radial alignment of glial fibers between the germinal pseudostratified epithelium and the outer surface occurred only in sectors of the neuro-ectodermal mass where a neo-cortex was present, and may therefore have been a critical determinant in the formation of the cortical plate. The integrity of the outer glial mesenchymal barrier may be necessary for the normal arrangement of cortical neurons.  相似文献   
5.
A female newborn presented with a huge mass protruding from the mouth. She had no respiratory distress but had difficulty swallowing. The mass originated from the tongue and was completely extirpated on the day of birth. The histologic diagnosis was mature teratoma. Three days later, another mass measuring 1 cm in diameter was found attached to the upper pharyngeal wall and was also completely extirpated 20 days after birth. The histologic diagnosis was also mature teratoma. The infant had a complete cleft palate, but no other malformation was found. Two years after surgery there is no sign of recurrence. Accepted: 22 August 1997  相似文献   
6.
儿童骶尾部畸胎瘤56例诊治分析   总被引:3,自引:0,他引:3  
目的:探讨儿童骶尾部畸胎瘤早期临床诊断及手术治疗要点。方法:对我院收治的56例儿童骶尾部畸胎瘤诊治资料进行回顾性分析。结果:5个月以内无恶性畸胎瘤患者,1~3岁患者恶性畸胎瘤达70%。良性畸胎瘤经手术治疗后全部治愈;恶性病例经手术及化疗在术后1~3年死亡。良性畸胎瘤如第一次手术未完整切除,也可恶变。结论:早期诊断,尽早彻底手术切除包括尾骨在内的病变组织及卫星病灶是避免恶变、彻底治愈儿童骶尾部畸胎瘤的关键。  相似文献   
7.
婴幼儿骶尾部良性畸胎瘤的MRI诊断   总被引:2,自引:0,他引:2  
目的:评估婴幼儿骶尾部良性畸胎瘤的MRI诊断价值。方法:回顾性分析6例经手术病理证实的骶尾部良性畸胎瘤的MRI表现。6例均用MRI的快速自旋回波序列扫描,结合短时反转恢复脂肪抑制序列及增强扫描。结果:骶尾部良性畸胎瘤起源于盆腔内末端骶尾区,属于后腹膜肿瘤,MRI通常表现为圆形、类圆形或不规则形巨大均质或非均质性肿块,边界一般较清楚,信号混杂,其中有代表囊性或实性成分的信号区域,实性部分常见脂肪或钙化。结论:MRI可清楚显示盆腔内、外的成分和解剖细节,有助于对骶尾部良性畸胎瘤的诊断以及合适手术计划的选择。  相似文献   
8.
Cardiac tumours in infancy are rare and are mostly benign with rhabdomyomas, fibromas and teratomas accounting for the majority. The presentation depends on size and location of the mass as they tend to cause cavity obstruction or arrhythmias. Most rhabdomyomas tend to regress spontaneously but fibromas and teratomas generally require surgical intervention for severe haemodynamic or arrhythmic complications. Other relatively rare cardiac tumours too are discussed along with an Indian perspective.  相似文献   
9.
Abstract

Behçet's disease (BD) is a chronic relapsing systemic vasculitis of unknown etiology. BD is very rarely associated with neoplastic diseases. We report the case of a 39-year-old woman who had been treated for BD for 3 years. She presented with relapsing oral and genital lesions and persistent high-grade fever which had lasted for 1 month. The possible cause of the exacerbation of BD and fever in this patient was a mature ovarian teratoma. To our knowledge this is the first report of a patient with BD associated with a ovarian teratoma.  相似文献   
10.
PurposeThe purpose of this study was to determine the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of ovarian mature teratoma in patients with anti-N-methyl-d-aspartate receptor encephalitis (NMDAR-E).Materials and MethodsA total of 125 women (mean age, 40.9 ± 17.8 [SD] years; age range: 12–85 years) with 146 histopathologically or radiologically proven ovarian mature teratomas who underwent preoperative CT and MRI examinations were retrospectively included. Eight patients with 11 teratomas had NMDAR-E, whereas 117 patients with 135 teratomas did not have NMDAR-E. CT and MRI examinations were retrospectively reviewed and teratomas in patients with NMDAR-E were compared to those in patients without NMDAR-E. Comparisons were performed using Mann-Whitney U test or Fisher exact test.ResultsIn patients with NMDAR-E, maximum diameter of teratomas (26.1 ± 9.3 [SD] mm), prevalence of teeth/calcification (36%) and rate of occupation by fat components (26%) were lower than those in patients without NMDAR-E (67.0 ± 37.6 [SD] mm [P < 0.01]; 75% [P < 0.05]; and 65%[P < 0.01], respectively). More than 75% of space was occupied by fat components in 76/135 teratomas (56%) in patients without NMDAR-E, whereas this was not observed in any teratoma in patients without NMDAR-E.ConclusionBy comparison with teratomas in patients without NMDAR-E, teratomas in patients with NMDAR-E are smaller, have few teeth/calcification, and the amount of space occupied by fat components is smaller.  相似文献   
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