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91.
Summary Investigation of the behaviour of the renal Juxtaglomerular apparatus in 19 patients with malignant hypertension has shown that in kidneys fixed immediately after operation the Juxtaglomerular granulation index is twice as high as in autopsy kidneys. The formation of renin by the epitheloid cells begins with the appearance of osmiophilic substances in the region of the endoplasmic reticulum. The first stages of granule formation are small rhomboid particles in the Golgi cisternes, which aggregate to form bigger round or polymorphic granules in the Golgi area.In pathological conditions the substances synthesized may be set free and become active locally as a result of fibrinoid necrosis of the vascular wall. The rate of production is increased firstly by forcing rhe production of active agents in the preexistent epitheloid cells, secondly by transformation of the so-called bivalent cells and finally, by cell division.In accelerated hypertension the production of renin also takes place in nephrons whose glomeruli, tubules and macula densa, are damaged. There is a correlation between blood pressure elevation and the Juxtaglomerular granulation index.
Zusammenfassung Untersuchungen über das Verhalten des juxtaglomerulären Zellkomplexes der Niere bei 19 Patienten mit maligner Hypertonie haben folgendes ergeben: In operativ gewonnenen und sofort fixierten Nieren ist der juxtaglomeruläre Granulationsindex doppelt so hoch wie in Nieren aus dem Sektionsgut. Die Reninbildung der epitheloiden Zellen beginnt mit dem Auftreten osmiophiler Substanzen im Bereich des endoplasmatischen Reticulums. Kleine rhomboide Gebilde in Golgizisternen sind Vorstufen von reifen Sekretgranula, die sich im Golgifeld zu größeren runden oder vielgestaltigen Sekrettropfen zusammenlagern.Unter pathologischen Bedingungen können infolge fibrinoider Gefäß- wandnekrosen Sekretsubstanzen lokal frei und lokal wirksam werden. Vermehrte Arbeitsleistung erfolgt zunächst durch Forcierung der Sekretproduktion in den präexistenten epitheloiden Zellen, sodann durch Transformierung sogenannter bivalenter Zellen und schließlich durch Zellneubildungen.Reninproduktion findet bei akzelerierter Hypertonie auch in solchen Nephronen statt, deren Glomerula und Tubuli samt Macula densa strukturell geschädigt sind. Es besteht eine Korrelation zwischen Höhe des Blutdruckes und Höhe des Granulationsindex.
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92.
We report the cytological and clinical findings of 16 fine-needle aspirates (FNAs) performed on recurrent (n = 6) and metastatic (n = 10) mixed mesodermal tumors (MMMTs). The median interval between the primary diagnosis and FNA was 16 mo. Primary sites were the endometrium (n = 11), the ovary (n = 3), the cervix (n = 1), and pelvic soft tissue (n = 1). Primary tumors showed carcinoma with homologous mesenchymal components in 13 cases and focal heterologous elements in three (two chondrosarcomas and one rhabdomyosarcoma). The FNAs showed carcinoma in all 16 cases, with adenocarcinoma differentiation in three, Mesenchymal elements were identified in aspirates of three recurrent and two metastatic lesions. They were all homologous. No heterologous mesenchymal elements were identified in the aspirates. We conclude that mesenchymal components in FNAs of MMMTs are less likely to be seen in metastatic lesions, and that heterologous mesenchymal components are rarely seen in these aspirates even in recurrent disease. These findings confirm that the epithelial component is responsible for the malignant behavior of MMMTs, and suggest that these lesions may need to be classified as sarcomatoid carcinomas rather than true carcinosarcomas. Diagn Cytopathol 1994;11:328–332. © 1994 Wiley-Liss, Inc.  相似文献   
93.
Summary Long-term studies of 2-PAG in sera of patients with breast cancer, bronchial carcinoma, gynaecological carcinoma, melanoma and laryngeal carcinoma have proved that 2-PAG is a possible laboratory parameter for the assessment of recurrence of tumour and metastasis. The results published for trophoblastic tumour and gastrointestinal carcinoma are still divergent. Because of the large individual range of 2-PAG concentrations and the widely differing 2-PAG levels in men and women single determinations of this protein are without value. A detailed classification of the pathological mechanisms to which these proteins are submitted is still missing and consequently we have no fundamental knowledge of diseases that apart from pregnancy and neoplasia lead to changes in the physiological 2-PAG serum concentration.Dedicated to Prof. Dr. E. Schmiedt to his 60th birthday (20th of November 1980)  相似文献   
94.
Malignant phyllodes tumour with a noninvasive ductal carcinoma component   总被引:2,自引:0,他引:2  
 A malignant phyllodes tumour with a noninvasive ductal carcinoma component is reported. The patient was an 80-year-old Japanese woman with a breast tumour detected by routine physical examination. A simple mastectomy was performed. The excised tumour was 10.5×9.4×5.4 cm in size and bulged into the skin with ulceration. The macroscopic appearance was that of a phyllodes tumour. Histologically the tumour consisted mainly of stromal components with a leaf-like structure lined by atypical ductal epithelium. The epithelial component showed gradual evolution to intraductal papillary carcinoma in a few areas. The stromal component was composed mainly of fibrosarcoma with areas of osteosarcoma and rhabdomyosarcoma. Neither stromal invasion of intraductal carcinoma nor transition between the stromal and epithelial elements was seen. Three months after the operation, death occurred, with multiple pulmonary and subcutaneous metastases. This case probably represents malignant change in both the stromal and the epithelial components of a phyllodes tumour. Since the two elements were independent, the possibility that a phyllodes tumour may be one of the origins of true carcinosarcoma is raised. Received: 11 March 1997 / Accepted: 5 May 1997  相似文献   
95.
Summary A 52-year-old male patient presented with a sudden painful loss of vision in both eyes. Ophthalmological examination revealed bilateral uveitis and marked bilateral nonrhegmatogenous retinal detachment near the optic disk. Systemic workup demonstrated IgM paraproteinemia. Abdominal ultrasound and computed tomographic studies revealed enlarged adrenal glands and irregular masses in the right hepatic lobe. Immune electrophoresis and multiple biopsy specimens established the diagnosis of systemic polymorphous immunocytoma. Polychemotherapy of this B-cell-derived type of non-Hodgkin's lymphoma led to a rapid remission and fast reduction of serous retinal detachment. We believe this is the first case of bilateral exudative retinal detachment as the initial ocular manifestation of systemic malignant B-cell lymphoma.Abbreviations Ig A Immunglobulin A - Ig M Immunglobulin M - qd every day - OD right eye - OS left eye - CT computerized tomography  相似文献   
96.
Summary The present report describes the results of a combined morphological, enzyme- and immunohistochemical analysis of nine cases of malignant non Hodgkin's lymphomas (NHL) clinically presenting as lethal midline granuloma. In a previous report written before antibodies directed against B and T lymphocytes were available, a histiocytic origin of such neoplasms had been suggested. A panel of antibodies reactive with most B cells (L26, MB1, KiB3) and a majority of T cells (MT1, UCHL1) was applied on paraffin sections of formalin fixed tissues as well as antibodies directed against leukocyte common antigen (LCA), myeloid/histiocyte antigen (MAC 387), lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, S-100 protein, prekeratin and immunoglobulin light chains. Enzyme histochemistry included tests for non-specific acid esterase, acid phosphatase, betaglucuronidase and chloroacetate esterase. As a result, five T, two B and two unclassified (malignant histiocytosis probable) NHL were identified, indicating distinct heterogeneity of NHL as causative disorders in lethal midline granuloma.  相似文献   
97.
The results of electron microscopic examination of cytologic specimens from six cases of mesothelioma and 10 cases of metastatic carcinoma of different origins are presented. The formation of cell clusters in malignant effusions from the two neoplasms has been thoroughly investigated: in mesotheliomas, cells had longer, more slender microvilli than in carcinomas and more abundant bundles of intermediate filaments; the central cavity often seen in the clusters frequently contained collagen and showed basement membrane production. The application of periodic acid-silver methenamine (PASM) and phosphotungstic acid (PTA) demonstrated a peculiar ultrastructural difference in cell coat staining in the two tumor types: in mesotheliomas, PTA and PASM were consistently negative along the outer surface of the cell aggregates, while carcinomas displayed a positive reaction either on the outer surface or on both inner and outer surfaces of the clusters. The diagnostic significance of the above-mentioned difference between the two neoplasms will require further investigation in a larger number of cases.  相似文献   
98.
Summary A 23-year-old man with myopathy with tubular aggregates had suffered from exercise-induced muscle cramps for 1 year. His general and neurological findings were normal. Laboratory investigations were within normal limits except for a slightly elevated serum creatine kinase level. Muscle biopsy showed some small angular fibres and scattered type 2B fibres with prominent tubular aggregates originating from the sarcoplasmic reticulum. Since the muscle fibres contracted at a lower concentration of caffeine, increased muscle fibre sensitivity to caffeine is probably related to muscle cramps in this disorder. Tubular aggregates are then secondarily formed in the muscle fibres.  相似文献   
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