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  • 1
    ISSN: 1432-2307
    Keywords: Microfold (membraneous) cells ; Tuft cells ; Electron microscopy ; Horseradish peroxidase ; Sequential uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 79 NMRI mice and Wistar rats were used for ultrastructural investigations of the sequential uptake of horseradish peroxidase (HRP) by M cells. In addition the ultrastructure of the so-called tuft-cells was reported. HRP, a foreign protein antigen, was applied either by injection (Owen 1977), or by stomach tube. After variable exposure times (5 min to 3 h) segments of the distal small intestine, containing Peyer's patches, mesenteric lymph nodes and liver tissue were removed. After fixation, they were reacted with H2O2-3,3′-diaminobenzidine tetrachloride and were examined by light and electron microscopy for HRP reaction products. The uptake of HRP mainly occurs through the M cells in the dome epithelium of Peyer's patches with a continual transport of the antigenic material into lymphoid cells, macrophages, and dendritic reticulum cells. In the 3 h specimens a few single HRP-positive lymphoid cells can be observed within the efferent lymphatics of Peyer's patches. In addition, a continual uptake of HRP by necrobiotic enterocytes was observed. It has also been shown that after 3 h HRP is located inside the Kupffer cells of the liver. These findings also support the presumption that antigenic material can be transmitted via the portal circulation. However, definite, quantitatively and permanently recorded uptake of HRP by brush border cells was not be observed. To exclude a toxic effect of the applied HRP on the enterocytic epithelium additional resorptive-physiological investigations were performed using the in vivo-perfusion-recirculation method and in vitro-accumulation of L-phenylalanine.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 392 (1981), S. 7-20 
    ISSN: 1432-2307
    Keywords: Keratin ; Filaments ; Epithelium ; Thymus ; Tumour diagnosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Autopsy specimens of normal human thymus, from cases of accidental involution, follicular hyperplasia, thymomas and a teratoma were investigated by immunocytochemistry using specific immune sera to small and large keratins. Keratin antisera represent a “marker” of both Hassall's corpuscles (HC) and so-called epithelial reticular cells. There were no apparent differences in keratin polypeptides distribution between cortical and medullary thymic epithelial cells. In accidental involution, the epithelial framework became prominent: epithelial cortical borders and epithelial perivascular sheaths appeared often to be discontinous structures. The central and occasionally cystic spaces of HC did not react with keratin antisera. In follicular hyperplasia, almost solid epithelial aggregates were seen which were located around germinal centers. In thymic tumours, neoplastic epithelial cells displayed a marked immunorectivity with keratin antisera. Immune sera against keratin filaments represent an interesting tool in thymus research and in the diagnostic pathology of thymic tumours.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 394 (1981), S. 133-141 
    ISSN: 1432-2307
    Keywords: Pulmonary benign tumors ; Leiomyoma ; Hamartoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die licht- und elektronenmikroskopischen Befunde an den Lungentumoren eines Falles mit multiplen pulmonalen Leiomyomen werden beschrieben. Die Differential-Diagnose der leiomyomatösen Lungentumoren und besonders die Abgrenzung von der pulmonalen Lymphangiomyomatose wird besprochen. Multiple pulmonale Leiomyome werden in der Literatur als Metastasen von “low grade” uterinen Leiomyomen oder aber als Hamartome der Lunge betrachtet. Letztere Annahme beruht auf der Tatsache, daß auf der Oberfläche der Tumoren und in ihrem Inneren sich kubisches, drüsenartiges Epithel befindet. Dieses weist jedoch nach unseren Beobachtungen Merkmale der granulären Pneumocyten (Typ II) auf, insbesondere lamelläre Körper im Zytoplasma und Microvilli an der Oberfläche. Die Ausbildung dieser epithelialen Bedeckung wird deshalb als Reaktion des Alveolarepithels auf das Tumorwachstum aufgefaßt. Als mögliches Muttergewebe der multiplen pulmonalen Leiomyome wird das kontraktile System der Lungenacini (kontraktile interstitielle Zellen) diskutiert.
    Notes: Summary The light and electron microscopical features of the lung tumors in a case of multiple pulmonary leiomyomas are described. The differential diagnosis of leiomyomatous tumors of the lung is discussed. They have to be differentiated from lymphangio-leiomyomatosis of the lungs. In the literature, multiple pulmonary leiomyomas are generally considered to be metastases from low grade uterine leiomyosarcoma or to be hamartomatous lung tumors. This is suggested by the glandular structures both within the tumor and on the surface. However, our ultrastructural observations showed these epithelia to have features of granular pneumocytes (type II), in particular they contain lamellar bodies and posess microvilli on their surface. Their formation is considered to be a secondary reaction of alveolar lining cells to tumor growth. A possible origin of multiple pulmonary leiomyomas from the contractile system of the lung acini (contractile interstitial cells) is discussed.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 391 (1981), S. 9-31 
    ISSN: 1432-2307
    Keywords: Intestinal lymphoma ; “Benign ulcerative non-granulomatous jejunitis” ; Coeliac disease ; Ulcerative colitis ; Immunohistology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The histology and immunohistology of twenty-seven malignant non-Hodgkin's lymphomas of the intestinal tract were studied. Nine of these cases were in the small intestine, ten in the ileocaecal region, two in the appendix and four in the large intestine. In one case, several locations in the gastrointestinal tract were involved. The so-called Kiel-Classification was applied. We have found thirteen lymphomas with low grade (lymphocytic, lymphoplasmacytic, centrocytic, centroblastic/centrocytic) and fourteen with high grade of malignancy (centroblastic, lymphoblastic, immunoblastic). For most of the lymphoplasmacytic and immunoblastic lymphomata a monoclonal pattern of intracellular immunoglobulin (IgM/kappa) was identified by the immunoperoxidase method. Tumour cells of lymphocytic, centrocytic, centroblastic/centrocytic, centroblastic and lymphoblastic lymphomas were always Ig-negative. The immunoperoxidase technique helped considerably in distinguishing between (monoclonal) malignant lymphomas and (polyclonal) lympho- or immunoproliferative processes. Six out of twenty-seven malignant lymphomas had developed from immuno-inflammatory diseases of the gut. Four of these were complications of coeliac disease. One had developed from a “malabsorptive” dermatitis herpetiformis Duhring, and one from a complication of a long-standing ulcerative colitis. In two patients with coeliac sprue and “malabsorptive” dermatitis herpetiformis Duhring respectively the ulcerating small intestinal lymphomas were initially misinterpreted as “benigne ulcerative non-granulomatous jejunitis”. The evidence from the literature summarized suggests strongly that the benign non-granulomatous jejunoileitis, lymphomatous ulcer, intestinal “pseudolymphoma” and malignant lymphoma, when associated with villous atrophy of adjacent mucosa and malabsorption symptoms, are all one condition, namely, malignant lymphoma.
    Type of Medium: Electronic Resource
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