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21.
38 cases of sarcoma of head and neck region were analysed in a retrospective way in relation to age, anatomic location, histological, clinical profile, and surgical approaches. Compared to other types of head and neck neoplasms, such as squamous cell carcinoma, soft tissue sarcomas have low rates of regional metastases. However the biological behaviour of soft tissue sarcoma is more aggressive specially in paediatric age group. In the present series, CT scan was considered as the primary modality of investigation. Surgery generally has been recommended as the primary method of treatment for achieving local control, except in those high-grade tumours arising in sites not amenable to resection. 3-year and 5-year survival rates in this present series 50% and 31.6% respectively.  相似文献   
22.
The movement of surface mounted targets (SMT) on a shell at the mid-shank and of bone mounted targets attached to the distal shank using a Percutaneous Skeletal Tracker (PST) were simultaneously measured during free-speed walking of three adult subjects having different body types. Surface movement errors in shank kinematic estimates were determined by expressing the segmental motion derived from the SMT relative to the PST-based segment coordinate system (SCS) located at the segment center of gravity. The greatest errors were along and around the shank longitudinal axis, with peak magnitudes of 10 mm of translation and 8° of rotation in one subject. Estimates of knee joint center locations differed by less than 11 mm in each SCS direction. Differences in estimates of net knee joint forces and moments were most prominent during stance phase, with magnitudes up to 39 N in the shank mediolateral direction and 9 N.m about the mediolateral axis. The differences in kinetics were primarily related to the effect of segment position and orientation on the expression of joint forces and on the magnitude and expression of joint moments.  相似文献   
23.
关于软腭下降机制的肌电图学研究   总被引:3,自引:0,他引:3  
目的探讨软腭的下降机制。方法将腭舌肌、腭咽肌设定为软腭下降肌,用肌电图学的方法进行验证。结果在软腭下降时腭舌肌、腭咽肌都出现了肌活动电位,另外,腭舌肌、腭咽肌在讲话时也参与了构音运动。结论腭舌肌收缩使软腭下降、鼻咽腔开放,腭咽肌由于具有咽绞扼功能,不但可使软腭下降,还与咽腔闭锁密切相关。  相似文献   
24.
目的 探讨舒肤特对座疮的治疗作用。 方法 病人随机分为治疗组和对照组。治疗组 45例 ,男 2 8例 ,女 17例 ;对照组 45例 ,男 2 5例 ,女 2 0例。年龄 14~ 42岁 ,平均 2 4岁。病程 2周~ 6年。治疗组用舒肤特 ,对照组用2 5 %氯霉素酊 ,每日 2次 ,4~ 8周为 1疗程。每周复诊 1次。 结果 治疗组痊愈率 3 7 8% ,总有效率 84 5 % ,对照组痊愈率 17 8% ,总有效率 62 2 % ,治疗组痊愈率优于对照组 ( χ2 =10 0 2 ,P <0 0 1) ,两组总有效率差异有显著性 ( χ2=11 42 8,P <0 0 1) , 结论 舒肤特是中西药复方制剂 ,其用于治疗痤疮效果较好 ,无明显副作用。  相似文献   
25.
非骨化性纤维瘤的X线平片与CT诊断   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:评价X线平片和CT扫描在诊断长骨非骨化性纤维瘤中的作用,旨在提高对该病的诊断与鉴别诊断水平。方法:对16例经手术病理证实的非骨化性纤维瘤的X线平片和CT特征进行回顾性分析。结果:肿瘤部位为胫骨9例,股骨6例,腓骨1例。肿瘤形态为卵圆形,肿瘤的长径2.0~8.0cm,肿瘤边缘均有硬化边。根据X线平片及CT所见分为2型:皮质型或偏心型(12例)和骨髓型或中心型(4例)。讨论:非骨化性纤维瘤的X线平片和CT表现具有特征性,对诊断和鉴别有重要作用。  相似文献   
26.
Ritschl  P.  Karnel  F.  Hajek  P. 《Skeletal radiology》1988,17(1):8-15
The radiomorphological appearance of fibrous metaphyseal defects (FMDs) is demonstrated by long-term follow-up studies. A characteristic radiomorphological course rather than a typical single appearance can be established. These findings correlate well with the duration of these tumor-like lesions; therefore, the radiological findings allow conclusions to be made about the age of a fibrous metaphyseal defect. In addition, the characteristic locations of FMDs will be explained in respect of their origins at insertions of tendons and ligaments.  相似文献   
27.
The case describes a 38-year-old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed.  相似文献   
28.
Fluid-fluid levels in cavernous hemangioma of soft tissue   总被引:3,自引:0,他引:3  
Five cases of cavernous hemangioma with fluid-fluid levels on magnetic resonance imaging and/or computed tomography are reported. The signal characteristics were those of blood and histological analysis of the fluid-fluid levels showed that they were blood-filled cavities in the tumor. Although this finding itself is not specific, it may help in confirming the diagnosis of cavernous hemangioma.  相似文献   
29.
Since peripheral odontogenic fibroma (POF) is characteristically described as a solitary lesion and no diffuse POF had been reported in the literature, our cases should be considered as extremely unusual. Three diffuse cases of POF are described of which one case was seen in association with ocular and skin lesions. The question arises whether POF should be considered as a true odontogenic tumor rather than a diffuse hamartomatous lesion caused by uncontrolled induction of the gingiva. It is also possible that such lesions could be part of a yet undescribed syndrome.  相似文献   
30.
A rare case of an infected chronic hematoma in a patient with immunodeficiency syndrome mimicking a soft tissue neoplasm is presented. There are few reported cases of hematogenous infection of chronic hematomas, which be difficult to differentiate from soft tissue neoplasms.  相似文献   
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