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71.
 Soft tissue tumours represent a heterogeneous group of mesenchymal lesions, and their classification is the subject of continuous debate. Chromosome analysis, molecular cytogenetics and molecular assays may become increasingly useful in diagnosis, and this review summarises advances in the cytogenetic characterisation and classification of soft tissue tumours. Among the group of fibrous lesions, superficial fibromatosis exhibits trisomy 8. This genomic change is also observed in desmoid fibromatosis in association with trisomy 20. Trisomy 11 is the most frequently observed chromosomal aberration in congenital fibrosarcoma. Dermatofibrosarcoma protuberans and giant cell fibroblastoma share a translocation t(17;22), which supports the concept of the existence of a common differentiation pathway. Adipose tissue tumours is the group in which integration of genetics and pathology has been most fruitful. Ordinary lipomas cytogenetically show an abnormal karyotype in about half the cases. Genomic changes of the 11q13 region are observed in hibernoma. Lipoblastoma exhibits a specific 8q rearrangement in 8q11-q13. Loss of material from the region 16q13-qter and 13q deletions are observed in spindle cell/pleomorphic lipomas. The well-differentiated liposarcoma/atypical lipoma group is characterised karyotypically by the presence of one extra ring and/or extra giant chromosome marker. Myxoid and round cell liposarcoma share the same characteristic chromosome change: t(12;16)(q13;p11) in most cases. In the group of smooth muscle lesions most data are derived from uterine leiomyomas, which can be subclassified cytogenetically into seven different types. Half of all leiomyomas are chromosomally normal; the other half have one of six possible consistent chromosome changes. Alveolar rhabdomyosarcoma is characterised cytogenetically by two variant translocations t(2;13)(q35;q14) and t(1;13)(p36;q14). Among tenosynovial tumours, the localised type of giant cell tumour of tendon sheath exhibits two different karyotypic changes. One involves 1p11 in a translocation with chromosome 2 or with another chromosome. A second type involves 16q24. Synovial sarcoma is characterised cytogenetically by a translocation occurring between chromosome 18 and presumably two adjacent loci on the X chromosome. In neural tumours, abnormalities of chromosome 22 have been reported in benign schwannomas and perineuriomas. Malignant peripheral nerve sheath tumours exist in two main forms: sporadic and associated with the NF-1 syndrome. Karyotypes are very complex, but chromosomes 17q and 22q are very often involved. Clear cell sarcoma is characterised cytogenetically and molecularly by a translocation t(12;22)(q13;q12). The Ewing’s sarcoma/peripheral neuroectodermal tumour category shows a central karyotypic anomaly represented by the translocation t(11;22). The two variants t(21;22) and t(7;22) are found in some cases. Among cartilaginous lesion, the most frequently described anomaly is the t(9;22)(q22;q12) in extraskeletal myxoid chondrosarcoma. Intra-abdominal desmoplastic small round cell tumour is characterised by a t(11;22)(p13;q12). Received: 5 February 1997 / Accepted: 24 February 1997  相似文献   
72.
气管与主支气管肿瘤的影像诊断(附32例报告)   总被引:5,自引:1,他引:4  
作者对32例经病理证实的气管与主支气管良、恶性肿瘤的影像学表现进行分析,归纳为3型:腔内型、壁增厚型和腔内外型。后2种类型提示恶性,而无蒂的腔内型表现者不能鉴别良,恶性。作者还评价了常规体层、CT及MRI诊断气管与主支气管肿瘤的优、缺点,讨论了影像诊断的作用。  相似文献   
73.
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features. These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical studies of both tumors.  相似文献   
74.
Summary With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas (P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93 vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore, be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex Doppler ultrasound and CDFI.  相似文献   
75.
76.
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity.  相似文献   
77.
本文用ELISA方法对110名住院病儿指末端毛细血管血和静脉血配对血标本中巨细胞病毒(CMV)抗体进行了对照研究。配对血标本检测CMV IgM、IgG抗体的一致性分别为99.09%和96.36%;敏感性分别为87.5%和95.58%;特异性分别为100%和98.48%。反复多次重复检测配对血标本中CMV抗体,结果均呈正相关。本结果表明:指末端毛细血管血可代替静脉血检测儿科病血中CMV抗体.这对儿科CMV感染病儿进行动态血清学监测具有重要意义。  相似文献   
78.
Compared with the knowledge on immobilization, the effects of remobilization on musculoskeletal tissues have not been well established. What is sure is that remobilization and rehabilitation of any component of the musculoskeletal tissues require much more time than the time needed to cause the immobilization atrophy. With intensive rehabilitation, the functional properties of skeletal muscles can be improved significantly even years after the injury and following immobilization, but no study has shown whether full recovery is possible and whether these rehabilitated muscles are able to respond normally to further training. Experimental studies have given evidence that slow-twitch muscle fibres have better capacity for recovery than fast-twitch fibres, most likely due to better circulation and higher protein turnover. Also evidence has been given that fibre regeneration is possible through satellite cell activation and myotube formation. Very little is known, however, about the effects of age, gender or the level of preimmobilization muscle performance on the restoration capacity. Also the fate of the marked structural changes (for example, connective tissue accumulation) induced by immobilization is unknown. Tendon and ligament tissues are likely to respond appropriately to remobilization, resulting in acceleration of collagen synthesis and fibril neoformation. However, there is a strong suspicion that remobilized tendons and ligaments will not achieve all the biochemical and biomechanical properties of their healthy counterparts. Specifically, the amount of weak type III collagen has been shown to be overrepresented in these tissues instead of mature, strong type I collagen. It is not known whether this is an important risk factor for ruptures during later activity. The effects of remobilization on muscle-tendon junction and proprioceptive organs are not known. It would not be surprising if the serious structural changes induced by immobilization were unrestorable. In the literature dealing with immobilization and remobilization, cartilage degeneration is always a major concern, because not only too strenuous training or immobilization, but also unskilful remobilization may activate this process leading finally to osteoarthrosis. Bone may be one of the best components of musculoskeletal tissues to respond to remobilization, probably because the immobilization atrophy of bone is largely quantitative (osteoporosis) only. The prerequisites for bony recovery are that the follow-up time is long enough (months) and that immobilization has not exceeded about 6 months, the time limit between active and inactive (irreversible) osteoporosis. Prevention of the atrophying effects of immobilization can be very successful if performed properly. According to present knowledge, there are many methods for the purpose, including preimmobilization training early, controlled mobilization; optimal positioning of the immobilized joint; muscular training during immobilization; early weightbearing; exercise with the nonimmobilized extremity; and electrical stimulation. Lots of education and information will be needed, however, before these methods are deeply rooted in the daily routines of the attending physicians, physical therapists, athletic trainers and other persons involved in the treatment of musculoskeletal problems.  相似文献   
79.
本文采用层析法进行鉴定,用氨基酸分析仪测氨基酸的含量,为胎盘组织液的质量标准提供可靠依据。本法准确率为99%。  相似文献   
80.
Granular cell tumors (GCT) are rare neoplasms, and only 173 cases of benign GCT of the breast have been documented. We report herein the cases of two patients with this tumor and discuss the methods of diagnosis and treatment. The first patient was a 60-year-old woman who presented with a firm ill-defined mass in her left breast. Mammography showed a dense shadow with spicula and skin thickness, and ultrasonography revealed a hypoechoic mass with an irregular border. Radical mastectomy was performed under the wrong preoperative diagnosis of breast cancer. The second patient was a 31-year-old woman who presented with an elastic-hard mass in her left breast. Mammography showed a well-demarcated dense mass, and ultrasonography revealed a well-defined hypoechoic mass with a large depth-width ratio. Fine-needle aspiration cytology (FNAC) showed a large number of histiocytic cells with abundant granular cytoplasm. An excisional biopsy was performed, and histological examination confirmed a diagnosis of GCT. GCT is benign, but often misdiagnosed as breast cancer both clinically and radiologically. Therefore, histological examination is essential for making a correct diagnosis, while FNAC is also useful. Local resection is still the treatment of choice, and surgeons should do their utmost to avoid performing needless radical mastectomy.  相似文献   
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