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11.
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
12.
Abstract The study of animal lectins and glycoconjugates has become an important area of research in biomedical sciences, as these molecules are believed to play important roles in a variety of biological processes. This report describes a study of the expression of an animal lectin, IgE-binding protein (?BP), also known as Mac-2 and CBP35, in human skin. We have analyzed cultured human keratinocytes as well as normal human skin and a number of epidermal neoplasms, by immunoblotting. immuno-fluorescence and immunohistochemistry. We showed that ?BP is expressed in human keratinocytes, hair follicles, sebaceous and sweat glands. We found that cBP expression retains in various epidermal neoplasms, including basal cell carcinoma, squamous cell carcinoma and keratoacan-thoma, although the level of expression appears to be reduced as compared to normal epidermis. The immunohistochemical analysis also suggests that the level of ?BP expression appears to be dependent on the degree of cellular differentiation of keratinocytes.  相似文献   
13.
Little work has been done with positive emission tomography (PET) in bladder tumors because high urinary excretion of (18)F-FDG makes visualization of the bladder tumor difficult. (11)C-choline has recently been reported as a new tracer which lacks urinary radioactivity. We report the result of (11)C-choline PET in four patients with invasive bladder tumors. In one case, (11)C-choline PET could detect bladder tumor effectively without urinary activity and bone metastasis despite negative bone scintigraphy. On the other hand, an intense accumulation of the tracer in the bladder hampered the interpretation on PET scanning in three patients. The mechanisms of the (11)C-choline accumulation in the bladder were reported to be due to inflammatory and proliferative changes in the mucosa of the bladder from previous catheterization or other factors. Further study is necessary to prove the value of (11)C-choline PET for detecting primary bladder cancer and bone metastasis.  相似文献   
14.
Summary Inactivation of tumour suppressor genes or anti-oncogenes as well as activation of dominant acting oncogenes seem to be important mechanisms in the pathogenesis of gliomas. We compared constitutional and tumoural genotypes at different restriction fragment length polymorphism loci (RFLP) on chromosomes 10 and 17 in 15 unrelated individualsLoss of heterozygosity (LOH) pointing to chromosomal loss or deletions was detected for at least one chromosme 17 marker in 11 gliomas (astrocytomas grades I–III and glioblastoma multiforme), whereas LOH for chromosome 10 loci was only detected in 3 out of 9 cases of glioblastoma multiforme and was not detected in low grade gliomas. Since LOH for chromosome 10 loci seems to be restricted only to glioblastoma multiforme, it is possible that recessive mutations on chromosome 10 are engaged in tumour progression from astrocytomas to glioblastoma multiforme. As LOH of chromosome 17 markers occurs in astrocytomas as in glioblastoma multiforme, chromosome 17 loci probably are involved in early tumour development.  相似文献   
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16.
Humoral hypercalcemia of malignancy is widely associated with tumor production of parathyroid hormone related protein (PTH-rP). This peptide functions in endocrine, autocrine and paracrine mechanisms in a manner similar to PTH; increasing renal uptake of calcium, decreasing retention of phosphorous, and stimulating adenylate cyclase and phospholipase C. Although PTH-rP production has been well documented in neoplasms of the exocrine pancreas, we present here two cases of endocrine pancreatic neoplasms elaborating PTH-rP. We then review the literature of previous cases and delve into the pathophysiology of this peptide.  相似文献   
17.
Magnetic resonance imaging (MRI) has greatly facilitated morphologic evaluation of spinal cord lesions. Eleven cases representative of inflammatory, demyelinating, neoplastic and vascular diseases, are presented which illustrate and summarize important abnormal features in spinal cord imaging, particularly MR findings. Recently, specialised techniques such as MR angiography, fat-inhibiting methods, dynamic MRI and functional imaging have been developed. These methods have facilitated not only lesion diagnosis but also qualitative assessment, and are being used to analyze pathophysiology. Comprehensive diagnoses based on such modalities may be important in determining indications for surgery or defining the extent of surgery or the intensity of other treatments.  相似文献   
18.
对100例前列腺增生患者的前列腺体积,年龄,血清前列腺特异抗原,抗原密度进行多元回归与相关分析。结果;年龄和前列腺体积与血清PSA浓度显著相关,其中,体积与PSA之间的年龄与体积之间具有相关性、而年龄与PSA之间无相关性,体积每增加10cm^3,PSA增高0.9μg/L。  相似文献   
19.
自1990年以来收治直径在2-5.6cm的大、巨型垂体腺瘤33例。依肿瘤生长形态与扩展范围将其简略分为三种类型。A型:瘤体位于鞍内或侵入蝶窦;B型;瘤体呈椭圆形或哑铃向鞍上扩展,三脑室明显移位抬高;C型:瘤体巨大侵入三脑室阻塞室间孔或明显的鞍周扩展。  相似文献   
20.
Mixed dysembryoplastic neuroepithelial tumor and ganglioglioma   总被引:3,自引:0,他引:3  
We report a case of a 15-year-old girl with new onset seizures, who had a mixed dysembryoplastic neuroepithelial tumor (DNT) and ganglioglioma of the right parieto-occipital lobe. The tumor appeared well demarcated and exhibited a low T1 and a high T2 signal on magnetic resonance imaging. Architecturally it was in large part intracortical and multinodular, but also featured a leptomeningeal component. The former corresponded to DNT, a proliferation of oligodendroglia-like cells (OLCs) arranged in nodules, as well as comprising a diffuse internodular element featuring “floating neurons” in a mucoid matrix. The leptomeningeal portion of the lesion was a ganglioglioma consisting of large neurons and astrocytes in association with marked desmoplasia. Spacially, the two components abutted one another but appeared distinct. Immunohistochemistry showed the neurons of the ganglioglioma to be positive for class III β-tubulin, synaptophysin, and chromogranin A, whereas the astrocytic cells stained only for glial fibrillary acidic protein. Most OLCs in the DNT were positive for S-100 protein. This apparently mixed lesion suggests that a close histogenetic relationship exists between DNT and ganglioglioma. We postulate that the pluripotential progenitor cells residing in the subpial granular layer may have given rise to the cortical DNT and to the leptomeningeal ganglioglioma. To our knowledge, this is the first detailed histological, immunochemical and ultrastructural report of a mixed DNT and ganglioglioma. Received: 11 August 1997 / Revised, accepted: 24 November 1997  相似文献   
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