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Between 1976 and 1984, 136 patients with portal hypertension due to extrahepatic obstruction were operated on. Twenty two patients had emergency and 114 elective operations. The operative mortality was 9% and 1%, respectively. Altogether 117 patients (86%) were followed up for from two to 10 years: 17 rebled, none developed encephalopathy or sepsis after splenectomy, and 90% and 75% were alive at five and 10 years respectively. Unlike endoscopic sclerotherapy and treatment with propranolol, operative treatment of variceal bleeding can usually be completed during one admission and carries a low mortality and a fairly low morbidity. Operation seems to be the best form of treatment for poor patients living far from medical facilities in developing countries and may be the treatment of choice in developed countries as well.  相似文献   
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Metastatic variants of human prostatic adenocarcinoma cell lines (DU-145, LNCaP, and ND-1) were studied by using soft agar colony forming efficiency, nude mice tumorigenicity, in vitro invasion assay, and type IV collagenase assay. The DU-145 and ND-1 cell line showed higher metastatic potential than LNCaP. Lipids from DU-145, ND-1, and LNCaP cells were extracted and analyzed by thin-layer chromatography and gas-liquid chromatography. The major lipids were phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, fatty acids, and cholesterol. The sphingomyelin level was significantly higher in highly metastatic cells (DU-145 and ND-1) compared with the lower metastatic variant (LNCaP). The increase in the synthetic pathway and decrease in degradation pathway of sphingomyelin in microsomal fractions was sufficient to account for the measured increase in sphingomyelin in DU-145 cells compared with LNCaP cells. The major fatty acids of these lipids were palmitic (16:0), stearic (18:0), oelic (18:1), and arachidonic acid (20:4). The arachidonic acid level was significantly decreased in DU-145 and ND-1 compared with LNCaP cells. Electron microscopic studies showed no significant changes in the morphology of DU-145, ND-1, and LNCaP cells. The results of these investigations demonstrate for the first time that sphingomyelin and arachidonic acid contents are different in high and low metastatic variants of human prostatic adenocarcinoma cell lines.  相似文献   
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Abstract: A subclone of NG108–15 neuroblastoma-glioma hybrid cells was used to study the intracellular distribution of opioid receptors. Subcellular organelles were separated on self-generating Percoll-sucrose gradients and the enzymes β-glucuronidase, galactosyltransferase, 5′-nucleotidase, and glucose-6-phosphatase were used as markers to localize the various structures. Analysis of the receptor distribution from untreated cells shows that the plasma membranes contained the highest receptor density, but a significant portion of the opioid binding sites was unevenly distributed between the lysosomes, microsomes, and Golgi elements. The enzyme markers indicated that appearance of opioid receptors in these intracellular structures does not result merely from contamination with plasma membranes. About 11% of the receptors appeared in a fraction lighter than plasma membranes. The antilysosomal agent chloroquine altered the intracellular compartmentation of the receptors, possibly by blocking their translocation in the cells. Leu-enkephalin induced time-dependent loss of receptors from all four intracellular compartments examined, but a kinetic analysis showed that the rate of receptor loss in these fractions was not identical. Thus, the percent of receptors appearing in the lysosomal fraction that could still bind [3H]-D-Ala2D-Leu5-enkephalin in vitro was increased on treatment with Leu-enkephalin. As an additional approach to follow the intracellular fate of the receptors, cells were labeled with [3H]diprenorphine, chased with various unlabeled opiates, and the distribution of 3H-ligand-receptors in the cells was monitored. Leu-enkephalin and etorphine altered the distribution of receptor-bound [3H]diprenorphine between the plasma membranes, lysosomes, and Golgi elements, whereas morphine had no such effect. The study sheds light on the role of intracellular structures in the metabolism of opioid receptors in untreated and opioid-treated cells.  相似文献   
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The present communication deals with a histological study of the pituitary gland of the teleost fish Mugil cephalus , found in the estuarine waters of Cochin area. Six different cell types were identified in the pituitary gland on the basis of their grouping, distribution and staining properties. The prolactin and the TSH cells (thyroid stimulating hormone producing cells or thyrotrops) were identified in the rostral pars distalis and the ACTH cells (adrenocorticotropic hormone producing cells or corticotrops) in the interphase between the neurohypophysis and the rostral pars distalis. The STH cells (somatotropic hormone producing cells or somatotrops) and the gonadotropic cells were distinguished in the proximal pars distalis and the MSH cells (melanin stimulating hormone producing cells or melanotrops) in the pars intermedia.  相似文献   
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Summary Horizontal cells of rat retina were labeled intensely by a specific antibody to cerebellar calcium-binding protein. The amacrine cells stained very weakly. The presence of calcium-binding protein in horizontal cells could be of interest for the understanding of the feedback action of these cells on photoreceptors.Abbreviations used CaBP calcium-binding protein - DAB 3,3-diaminobenzidine - PAP unlabelled antibody peroxidase-antiperoxidase immunocytochemical complex On leave from the Department of Physiology, University of British Columbia, Vancouver, Canada  相似文献   
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