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21.
M. John Hicks Victor A. Saldivar Murali M. Chintagumpala Marc E. Horowitz Linda D. Cooley James P. Barrish Edith P. Hawkins Claire Langston 《Ultrastructural pathology》1995,19(5):395-400
Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation. 相似文献
22.
Yosuke Morimitsu Hiroshi Tanaka Shigeaki Iwanaga Masamichi Kojiro 《Pathology international》1993,43(4):204-208
A rare case of an alveolar soft part sarcoma of the uterine cervix in an 8 year old girl is presented. The patient was admitted because of genital bleeding lasting for 7 months. A polypoid tumor, 2times1.5 cm in diameter, was found in her external uterine os and was surgically resected. Microscopically, the tumor consisted of a uniform sheet of tumor cells in the cytoplasm which contained granules and which were stained with periodic acid-Schiff, both before and after the diastase digestion. Alveolar arrangement of the tumor cells was manifested with reticulin silver impregnation. Dense, membrane bound granules were evident at an ultrastructural level in the cytoplasm of the tumor cells. An immunohistochemical examination demonstrated a positive reaction for anti-desmin, anti-myoglobin, anti-HHF35 and anti-neuron specific enolase in the cytoplasm. 相似文献
23.
Differentiating Small Round Cell Sarcomas of the Soft Parts by an Innovative Immunogold Labeling Method: An Ultrastructural Study 总被引:1,自引:0,他引:1
A new immunoelectron microscopy procedure was developed by remaking the fixed-frozen tissue specimens into LR White resin blocks suitable for postembedding colloidal gold immunolabeling, and used to examine 16 cases of small round cell soft tissue sarcomas. In rhabdomyosarcoma, ultrastructural double-immunogold staining demonstrated a coexpression of muscle specific actin and desmin in the same tumor cell. In both Ewing's sarcoma and peripheral neuroepithelioma, the heterogeneous expression of MIC2 gene product (p30/32MIC2) in each tumor cell was demonstrated as well. In peripheral neuroepithelioma, the colloidal gold immunolabeling for neurofilament demonstrated the intermediate filaments surrounding microtubules. The procedure for ultrastructural colloidal gold immunolabeling using fixed-frozen tissue is thus considered to be useful not only for tumor diagnosis, but also for investigating various subcellular structures. 相似文献
24.
远端蒂腓肠神经营养血管皮瓣与肌皮瓣的临床应用与改进 总被引:6,自引:0,他引:6
目的:报道应用远端蒂腓肠神经营养血管皮瓣,肌皮瓣修复小腿下段及足踝部软组织缺损的可行性安全性和临床效果。方法:对42例以远端蒂腓肠神经营养血管(肌)皮瓣修复小腿下段及足踝部不同原因所致软组织缺损病例进行总结分析。本组男36例,女6例;年龄最大75岁、最小6岁;皮瓣最大面积17.0cm×15.0cm,最小6.0cm×5.0cm,其中12例皮瓣面积在10.0cm×10.0cm以上;6例设计为肌皮瓣(腓肠肌外侧头),肌瓣最大为10.0cm×7.0cm×2.0cm,最小为6.0cm×5.0cm×1.0cm。结果:所有病例术后皆出现不同程度的皮瓣肿胀,暗道较明道者明显。2例大皮瓣经行小隐静脉远端结扎仍出现肿胀、色暗,皮瓣近侧1/3坏死。皮瓣边缘坏死3例,换药治愈。部分坏死需行植皮者3例。36例术后伤口I期愈合,骨外露软件组织缺损覆盖修复满意,6例II期愈合,其中糖尿病,地中海贫血各一例。结论:(1)远端蒂腓肠神经营养血管皮瓣转位修复小腿下1/3及足踝部缺损创面,极有临床实用价值;(2)设计切取腓肠神经营养血管肌皮瓣修复小腿及足踝填充感染创腔是可行的;(3)但对其皮瓣及所携带的肌瓣究竟切取多大面积是安全的、肌瓣的血运机理以及远端蒂筋膜皮瓣中小隐静脉干是否结扎,何处结扎等问题仍有待进一步研究。 相似文献
25.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习 总被引:1,自引:2,他引:1
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。 相似文献
26.
Extrapleural solitary fibrous tumor: clinicopathologic study of 17 cases and molecular analysis of the p53 pathway 总被引:9,自引:0,他引:9
Morimitsu Y Nakajima M Hisaoka M Hashimoto H 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(9):617-625
Solitary fibrous tumor (SFT) occurring at various extrapleural sites is sometimes difficult to diagnose because of its histologic variability. Although a solitary fibrous tumor is usually a slow-growing tumor with favorable prognosis, a small number of malignant cases have been reported. In the present study, we examined the clinical behavior, histologic, immunohistochemical and molecular features of 17 cases of extrapleural SFT. Four tumors were located in the pelvic cavity, two in the nasal cavity, two were confined to the pulmonary parenchyma, and there was one each in the meninges, kidney, mediastinum, retroperitoneum, temporal region, neck, groin, buttock and thigh. Histologically, all the tumors were characterized by the presence of areas consisting of a proliferation of bland spindle cells with variable amounts of thick, often hyalinized or keloid-like intercellular collagen bundles. Highly cellular areas were observed in three tumors, frequent mitoses in two, and cellular pleomorphism and tumor necrosis in one each. All 17 tumors showed immunoreactivity to CD34 and 15 (88%) to bcl-2 protein. The labeling indices of p53, mdm2 protein and Ki-67 were generally low. PCR-SSCP and a subsequent sequence analysis of the p53 gene disclosed point mutation at codon 161 in exon 5 in one of the 13 cases analyzed. According to follow-up information, none of the patients had developed local recurrence or distant metastasis. Our results suggest that most extrapleural SFTs behave in a benign fashion even in a higher histologic grade group, and it is difficult to predict their clinical outcome. Complete surgical excision in order to obtain clear margins and long-term follow-up is advisable for patients with an extrapleural SFT. 相似文献
27.
目的 :探讨纤维支气管镜检查和经纤维支气管镜肺活检 (TBLB)对周围及弥漫性肺疾病的诊断价值。方法 :对 46 0例周围及弥漫性肺疾病患者 ,在无X线电视透视下行TBLB ,对临床资料及病理诊断结果进行回顾分析。结果 :46 0例周围及弥漫性肺疾病中有 35 1例明确了病因学的诊断 ,确诊率达 76 3% ,疾病种类主要有肺癌、肺结核、肺间质纤维化、肺结节病等 ,对临近胸膜的病变TBLB阳性率较低 ,并发症少见 ,仅有少量出血及发热 ,或偶有气胸。结论 :纤维支气管镜肺活检对周围及弥漫性肺疾病的诊断是一种可靠、安全、简便、经济、可重复操作的方法。 相似文献
28.
恒力法测量运动对动物肌腱,韧带横截面积的影响 总被引:2,自引:0,他引:2
刘波 《生物医学工程学杂志》1993,10(4):349-352
本文介绍一种方便,适用的肌腱,韧带横截面积的测量工具-软组织横截面积测微计。通过对兔屈趾肌腱反复测量,其重复性精密度在0.044mm以内,变异系数在1.4%以下,用该测微计对大强度训练一段时间后的兔屈趾肌腱,跟腱和膝内侧副韧带的测量发现,训练训练后FDP,AC的横截面积减小,MCL有增大的趋势,据此,作用认为肌腱的变化与长期大强度训练后试件的“疲劳蠕变”有关,MCL的变化则与在体内的负荷形式有关。 相似文献
29.
Summary Transforming growth factors (TGF) induce the soft agar growth of nontransformed cells, such as NRK-49F cells. This report describes culture conditions that optimize the detection of TGF by NRK-49F cells. Two aspects are dealt with in depth: the need to select an appropriate clone of NRK-49F cells and the need to select a culture medium that supports little or no background growth in the absence of added TGF. Evidence is presented to demonstrate that medium supplemented with heat-treated, dialyzed bovine plasma provides better conditions for assaying TGF than serum-supplemented medium provides. 相似文献
30.
Usefulness of basement membrane markers in tumoural pathology 总被引:7,自引:0,他引:7
The distribution of basement membrane (BM) markers, type IV collagen, laminin (LM), heparan sulphate proteoglycan (HSP) and fibronectin (FN) has been studied by indirect immunofluorescence using specific antibodies, in tumoural pathology. The disrupted pattern of BM by these markers in severe dysplastic lesions of the breasts, the bronchi and uterine cervix provides evidence for malignancy. In invasive carcinomas, there is generally a loss of these BM components, with FN persisting in the stroma. The loss of these markers in BM is concomitant and superimposable in double staining studies. In embryonic tumours, the presence of BM markers is related to a mesenchymal differentiation of malignant cells with pericellular FN and/or maturation towards organoid structures with BM. In sarcomas, there is a loss of the pericellular BM staining around most transformed muscular and Schwann cells and adipocytes. The persistence of this labelling in some well-differentiated areas can help to diagnose the nature of the sarcoma. The persistence of intercellular filaments of FN corresponds to the mesenchymal and/or sarcomatous nature of undifferentiated anaplastic proliferations. 相似文献