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61.
Six examples of histologically diagnosed, non-invasive breast carcinomas were studied by electron microscopy to elucidate the ultrastructural features for an accurate diagnosis of in situ carcinoma. The results obtained revealed two patterns of basal lamina/stromal cells relationship. One pattern showed intact basal lamina with associated periductal stromal cells consisting entirely of fibroblasts, the other pattern showed disruption of basal lamina by gaps and malignant cell protrusions with associated stromal cells consisting of both fibroblasts and myofibroblasts. As myofibroblasts are not a component of normal breast stroma but are known to be a prominent feature in the stroma of infiltrating breast carcinoma, the present observations suggest that myofibroblastic proliferation around in situ carcinoma represents an early sign of carcinomatous infiltration. Hence the definitive diagnosis of non-invasive carcinoma of the breast requires an intact basal lamina and a complete absence of a myofibroblastic reaction. 相似文献
62.
M. Réthelyi 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1970,11(2):159-174
Summary An electron microscopic analysis of the synapses in Clarke's column of the cat, using fresh short term degeneration, long term degeneration for detection of the persisting elements, and a newly devised two-step degeneration technique using fresh short term degeneration for further analysis of the persisting synaptic elements in chronic degeneration cases. — Three kinds of synaptic terminals can be identified in the lower part (L3 segmental level) of Clarke's column: (1) very large (so-called giant) axon terminals with spheric vesicles of primary muscle afferents establishing multiple (climbing-type) contacts mainly with the large dorsal spinocerebellar tract neurons; (2) small bouton-type terminals having spheric synaptic vesicles and originating mainly from spinal interneurons, localized below L4 in the lumbar enlargement and contacting small distal dendrites and cell bodies of small cells; (3) two types of nerve terminals, originating from local neurons, and characterized by flattened vesicles. One type of (3) contacts mainly the large Clarke neurons directly, whereas the other establishes axo-axonic synapses with the giant terminals (1) of primary muscle affer ents. The possible functional significance of these findings is discussed. 相似文献
63.
胰腺实性-假乳头状肿瘤内PTEN和nestin的表达 总被引:1,自引:0,他引:1
目的 探讨胰腺实体假乳头肿瘤(SPTP)细胞可能的组织学起源。方法 复习25例SPTP的临床病理特征,常规HE和超微结构观察,免疫组化EnVision法染色检测肿瘤细胞PTEN和nestin等的表达。结果 25例SPTP中女性22例,男性3例,中位年龄22.3岁。肿瘤主要位于胰腺内,1例位于后腹膜并与胰腺相连。1例伴有肝转移。肿瘤呈囊实性,出血、坏死明显。肿瘤细胞大小形态较一致,实性和假乳头状排列,部分似“室管膜样”菊形团。核卵圆形,有核沟,核仁不明显,核分裂象少见。肿瘤细胞均有PTEN阳性表达(18/18,100%),44%(8/18)的病例有nestin的表达。超微结构观察细胞内可见酶原样分泌颗粒和神经内分泌颗粒。结论 胰腺实体假乳头肿瘤可能起源于胰腺多能干细胞。 相似文献
64.
Claire M. Payne Raymond B. Nagle Samuel H. Paplanus Anna R. Graham Martin M. Berman 《Ultrastructural pathology》1986,10(6):539-552
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature. 相似文献
65.
Cutis laxa: autosomal dominant inheritance in five generations 总被引:3,自引:0,他引:3
Cutis laxa is described in three cases: a 17-year-old man, his mother and his maternal grandmother. The onset of skin symptoms occurred from puberty to early adulthood. The skin was loose-hanging, wrinkled and without elasticity. X-ray examination showed numerous gastrointestinal diverticulae in the two older patients, and both had been operated on for abdominal hernia and genital prolapse. There were no cardiopulmonary symptoms. Histopathological investigation showed a reduction in the amount of elastic tissue in the dermis, but normally localized and ultrastructurally normal components. The family history revealed clinically similar cases in at least five generations, consistent with autosomal dominant inheritance. 相似文献
66.
L. A. Kopteva L. I. Zhevalyukova V. I. Biryuzova 《Bulletin of experimental biology and medicine》1978,86(3):1160-1163
Acute cardiac ischemia caused by ligation of the descending branch of the left coronary artery leads to a sharp increase in the activity of the protein-synthesizing system of the inner mitochondrial membranes of the myocardium throughout the period of organization of the experimental infarct, as reflected in an incease in the synthesis of protein and RNA in the mitochondria. During development of the infarct considerable changes are observed in the ultrastructure of the inner mitochondrial membranes of the myocardium, the degree of which is directly dependent on the stage of development of the pathological process.Institute of General Pathology and Pathophysiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. N. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 9, pp. 295–297, September, 1978. 相似文献
67.
Nepomnyashchikh LM Lushnikova EL Semenov DE 《Bulletin of experimental biology and medicine》2000,130(12):1196-1201
We studied ultrastructure of nuclear compartment in cardiomyocytes during regenerative and plastic insufficiency of the myocardium induced by anthracycline antibiotic daunomycin. A peculiarity of ultrastructural organization of cardiomyocyte nuclei under these conditions is almost complete disappearance of the heterochromatin lumps. The earliest changes in nucleoli under conditions of disturbed DNA-dependent RNA synthesis are segregation of the granular and fibrillar nucleolonema components. Deep alterations in the nucleoli manifested by fragmentation and annulation correlate with pronounced changes in cardiomyocytes ultrastructure, intensive lysis of the myofilaments, reduction of the organelles, and enhanced autophagocytosis. 相似文献
68.
The pattern of amyloidosis in a Malaysian patient population 总被引:1,自引:0,他引:1
L.M. LOOI 《Histopathology》1991,18(2):133-141
Congo red screening of 27,052 routine biopsy specimens from 22,827 patients over a 5 1/2-year period in the Department of Pathology, University of Malaya detected 186 cases of amyloidosis. The categories of amyloidosis encountered and their prevalences in relation to each other were: systemic AL (5.9%); systemic AA (3.2%); isolated atrial (14%); primary localized cutaneous (7.5%); other primary localized deposits (3.2%); localized intratumour (58%); and dystrophic (8.6%). A third of patients with systemic AL amyloidosis had coexistent immunocyte abnormality. The commonest underlying pathology for systemic AA amyloidosis was leprosy. Notable among the types of localized amyloidosis revealed by this study were isolated atrial amyloidosis, which appeared to complicate chronic rheumatic heart disease, and intratumour amyloidosis complicating nasopharyngeal carcinoma. Other tumours in which amyloid deposits were observed included basal cell carcinoma, islet cell tumour and medullary carcinoma of the thyroid. Dystrophic amyloidosis was observed in fibrotic tissues, such as damaged cardiac valves and osteoarthritic joints. Heredofamilial amyloidosis, senile systemic amyloidosis and degenerative cerebral amyloidosis were notably absent from this study. 相似文献
69.
L. M. Nepomnyashchikh L. A. Semenova D. E. Semenov 《Bulletin of experimental biology and medicine》1989,107(4):546-551
Department of Pathomorphology and Morphometry, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR. Laboratory of Functional Morphology and pathology of the Cell, Institute of Cytology and Genetics, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 477–481, April, 1989. 相似文献
70.