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Summary A polypoid tumor was surgically removed from the second part of the duodenum of a 56-year-old male. The main body consisted of large epithelioid cells arranged in an adenoma like pattern of strands and nests. These cells were argyrophil and had marked nonspecific esterase activity. Unmyelinated nerves with proliferated Schwann cells accompanied these epithelioid cells together with scattered gangliocyte like elements. Ultramicroscopically, the epithelioid cells were seen to contain round electron dense granules, 150 nm in diameter on average. The tumor is considered to be a nonchromaffin paraganglioma, as it probably developed from paraganglion cells associated with small arteries or branches of the vagus nerve, or from the undifferentiated pluripotent APUD cells of the duodenum.  相似文献   
13.
Responses of nasal mucociliary transport mechanisms to exposure to 6 ppm SO2 were studied in chickens in vivo. This model takes advantage of the natural cleft palate which exposes the mucociliated base of the nasal septum. Exposure to 6 ppm SO2 decreased the mucociliary transport rate along the base of the nasal septum. The minimum force required to move an iron particle along this area of mucous membrane by use of a magnetic field in vivo increased significantly after SO2 exposure, while the minimum force required to move an iron particle on a pool of mucus collected from the same chicken and tested in vitro showed no change after SO2 exposure. The elastic recoil distance of mucus was measured both in vivo and in vitro. The in vivo recoil distance decreased significantly after SO2 exposure, while SO2 exposure did not change recoil distance in vitro. It is proposed that exposure of chickens to SO2 results in the formation of multiple points of adhesion of strands of mucus between the acinar gland cells and the emergent extracellular mucus or adhesion of a mucous blanket to the cilia, causing mucociliary transport to be retarded or static.  相似文献   
14.
本文报告8眼丁字形泪囊鼻腔吻合术,其中6眼追踪观察廿年获得完全治愈;1眼观察6个月效果良好 1眼愈后不详。同时对主要手术步骤做了介绍,鼻粘膜瓣环钻法改用十字切开法更易于吻合。  相似文献   
15.
Gastrointestinal polyps are common lesions that usually present singly or in small numbers. Although the term ‘multiple colorectal polyposis’ was originally applied to patients carrying at least 100 large intestinal adenomas, it has subsequently become broadened to include patients carrying multiple polyps regardless of their nature. Most of the non-adenomatous polyposis syndromes are hereditary. They can be classified according to the dominant type of polyp, their distribution in the gastrointestinal tract and their potential for the development of gastrointestinal cancers. This review summarises their main clinical, genetic and histopathological features.  相似文献   
16.
孤立性蝶窦病变的诊断与治疗   总被引:1,自引:1,他引:0  
目的;提高孤立性蝶窦病变的诊断和治疗率。方法;总结使用鼻窦内窥镜诊治孤立性蝶窦病变12例的全过程。结果:12例孤立性蝶窦病变的患者的均获准确诊断,使用鼻窦镜行经鼻腔蝶窦手术,有效率为83.3%,随访6 ̄24个月,10例无复发,复发2例二次手术后治愈;结论:孤立性蝶窦病变患者可用鼻窦内窥镜诊断与治疗。  相似文献   
17.
血管运动性鼻炎激光治疗鼻腔粘膜致敏区的筛选   总被引:1,自引:0,他引:1  
目的 :随访和对比激光治疗血管运动性鼻炎鼻腔粘膜不同区域的致敏性 ,以明确最佳治疗点。方法 :随机选择确诊的血管运动性鼻炎 1 0 3例 ,分为下鼻甲、中鼻甲、中鼻甲前 1 /3段 3组进行激光治疗。结果 :下鼻甲组总有效率为 66.7% ,中鼻甲组为 97.1 % ,中鼻甲前 1 /3段为 94.4% ,两中鼻甲组与下鼻甲组总有效率差异有显著性 (P<0 .0 0 5) ,中鼻甲组与中鼻甲前 1 /3段组总有效率差异无显著性 (P>0 .0 5)。结论 :中鼻甲前 1 /3段是血管运动性鼻炎患者鼻粘膜最敏感的区域 ,是最佳激光治疗点。  相似文献   
18.
目的:探讨应用针形内窥镜对小儿鼻颅底疾病进行探查与手术的方法及疗效。方法:在外径1.9mm的进口针形内窥镜及电视同图像系统监视下,对8例小儿(7d ̄12岁)鼻颅底有关疾病进行探杳与手术。结果:先天性后鼻孔闭锁3例中,1例好转,3例痊愈。外伤性脑脊液鼻漏1例,经修补痊愈先天性脑膜脑膨出2例,确诊后1例暂缓治疗。另1例行内窥镜手术痊愈。颅底神经母细胞瘤2例取材作病理检查确诊。结论:在电视图像监视下应用  相似文献   
19.
In this paper we have analyzed the physical properties of nasal mucus from 120 outpatients with rhinitis. We focused on the most relevant rheological features: viscosity, elasticity, adhesiveness, as well as ability to be spun (spinability) or poured (pourability). A double-capillary type viscometer was used to measure viscosity and elasticity and the platinum ring method to measure adhesiveness. Spinability was measured with an automatic apparatus (Filancemetre Sefam) and pourability was determined by describing flow under gravity. Efficacy of nasal clearance was analyzed by measuring mucociliary transport time with an inert tracer using vegetal charcoal powder. Results showed that impaired nasal mucosal function in patients with rhinitis could be determined by studying rheological features in addition to measuring mucociliary activity. Information provided proved invaluable when considering possible treatment with agents affecting kinesis of nasal mucus.  相似文献   
20.
Fibroepithelial polyps are the most frequently observed mesenchymal tumors of the renal pelvis. We report on one case of fibroepithelial polyp of the renal pelvis with unusual CT findings of totally cystic structure with septations. Received: 27 July 1998; Revised: 6 January 1999; Accepted: 8 February 1999  相似文献   
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