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121.
Summary Data are reviewed on the amino acid metabolism in patients suffering from transient acute polymorphic psychoses according to ICD-10. The psychotic episodes of many of these patients are characterized by distorted sensory perceptions and intense emotional states; plasma amino acid analysis revealed a disturbed serine-glycine metabolism.In remitted patients oral loading with serine induced the characteristic dysperceptions and psychedelic symptoms. Plasma concentrations of serine and methionine were decreased, and the concentration of taurine was increased. Fibroblast experiments suggest that the activities of the serine metabolizing enzymes serine hydroxymethyltransferase and cystathionine-synthase are increased in these patients.The determination of plasma amino acid concentrations proved to be useful in discriminating these patients. The prevalence of this transient psychosis in a psychiatric in-patient population ranged between 1.4 and 3.6%.  相似文献   
122.
A case of cutaneous zygomycosis caused byAbsidia coryabifera in a leukemic patient submitted to chemotherapy is reported. The lesion was located on the little finger of the right hand and probably resulted from a latent osteomyelitis. It progressed to form extensive necrotic area. No systemic infection was detected and the lesion did not appear to be associated with any trauma.  相似文献   
123.
Turkey poults were given either of two different dosages of two different gliotoxin-producing strains ofAspergillus fumigatus. Infected lung tissue was examined postmortem for the presence of gliotoxin. Gliotoxin was found in lung tissue of ten poults infected with one strain and in seven of ten poults infected with the other strain. Concentrations of gliotoxin in the tissue exceeded 6 ppm in some of the infected tissues. The concentration of gliotoxin found in infected tissue did not appear to be correlated with the dosage of organism given. Considering the pathologic changes observed in turkey poults with aspergillosis and the production of gliotoxin during the pathogenic state in turkey poults, gliotoxin is considered likely to be involved in avian aspergillosis. Disclaimer: Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.  相似文献   
124.
125.
Difference spectra of the crude cell-free extract ofAzospirillum brasilense sp. 7 indicate the presence of cytochrome b, cytochrome c, and one CO-binding pigment that exhibits the spectral characteristics of cytochrome o. All the pigments are present in varying concentrations at all stages of growth. With progress of the bacterial growth, there is a linear increase in the level of cytochrome b with a disproportionate increase in the level of cytochrome c. At the stationary phase, the amount of cytochrome b and c is increased by about sevenfold compared with that in the early log phase. The increase in the concentration of total cytochrome is not accompanied by an increase in the respiration rate of the cells. Both cytochrome b and cytochrome c are located in the particulate fraction of the cells and are not fully reducible by succinate alone.  相似文献   
126.
A 55-year-old man was admitted to the hospital for an elective herniorrhaphy. A significant past history of smoking and alcohol abuse was noted. The patient had no other complaints but a routine chest X-ray revealed an isolated left upper lobe mass. Laboratory tests were unrevealing and the impression was that the patient had a carcinoma. The surgical specimen consisted of a lobular mass containing multiple microabscesses. Grains consistent with actinomycosis were seen and the cultures grew out Actinomyces meyeri. There was no other evidence of disease.  相似文献   
127.
Summary Blood cells proliferate extravascularly in the bone marrow and enter the circulation by migrating through endothelial cells of venous blood sinuses. This migration, or diapedesis, was suspected to involve actin. To test for the presence and distribution of actin, sections of rat bone marrow were examined by indirect immunocytochemistry. Affinity purified rabbit antichicken gizzard actin antibody, and goat-antirabbit IgG-FITC, or goat antirabbit IgG colloidal gold probes were used. The migrating cell contacts the endothelial cell and forms a podosome (a cortical bleb). Immunocytochemistry shows this region to contain actin. As diapedesis proceeds the podosome deforms, then breaches the endothelial cell. At this time the anterior portion of the leukocyte shows heavy labeling for actin. When the migratory cell traverses approximately half of its length through the endothelial cell, actin appears prominent in the caudal region of the cell. The immunocytochemical data suggest that actin is nonrandomly distributed in leukocytes undergoing diapedesis and may be a component of the force-generating mechanism responsible for this transcellular migratory event.Supported in part by grants from the American Cancer Society, Illinois Division, Inc. (83-4), and NIH (GM 28397)  相似文献   
128.
Summary Examination of the parotid gland of the rat has shown specific associations of cisterns of the endoplasmic reticulum with gap junctions. About 20% of the junctions are so intimately associated with cisterns of the endoplasmic reticulum that in freeze fractured material the cisternal membranes remain attached to the junctional membrane faces, obscuring most of the junctional array except for a thin ring of telltale particles. This association was seen only in the parotid gland of the rat, but not that of the other species examined.  相似文献   
129.
Summary Ornithine decarboxylase, a key enzyme in polyamine biosynthesis and cell growth, has been localized in mouse kidney by autoradiography after administration of radiolabeled -difluoromethylornithine. This drug is an enzyme-activated irreversible inhibitor of ornithine decarboxylase and forms a covalent bond with the enzyme. It was found that ornithine decarboxylase is present in all cell types studied but that the highest content occurs in the proximal convoluted tubules followed by the distal convoluted tubules and the collecting tubules. The majority of the enzyme is located in the cytoplasm but about 10–15% is present in the nuclei (often associated with nucleolus-like components) of the cells of the proximal and distal convoluted tubules. The labeled ornithine decarboxylase was lost rapidly from both nucleus and cytoplasm of all the cell types examined, and labeling by radioactive -difluoromethylornithine was greatly reduced if the mice were pretreated for 5 h with cycloheximide to block protein synthesis. These results indicate that ornithine decarboxylase turns over rapidly in all of the cells.  相似文献   
130.
Summary Amino acid transport and incorporation have been studied in vitro in rat pancreatic lobules after maximal and supramaximal hormonal stimulation with caerulein. Incorporation into proteins was increased already after 30 and 120 min of maximal stimulation, but was decreased after the infusion of a supramaximal dose. Uptake of neutral amino acids was monitored using labeled leucine and -aminoisobutyric acid (AIB). In the case of leucine the free pool was consistently reduced after maximal stimulation, while supramaximal doses led to an increase which could be potentiated by the addition of 2mM tetracaine. Using AIB, a significant increase in the intracellular pool was observed after maximal stimulation, conversely a decrease after supramaximal stimulation. Release of labeled leucine and AIB from preloaded lobules during incubation in the cold was significantly reduced after maximal secretory stimulation, but was found enhanced by 200 to 300 percent after supramaximal stimulation. No fine structural alterations at junctional complexes or at both the lateral and luminal plasma membranes were observed after maximal stimulation except an increased number of exocytotic figures at the luminal face. However, supramaximal stimulation led to progressive rarefaction of the tight junctional network and disintegration of the gap junctions. Concomitantly, an equal distribution of membrane particles on both faces of the plasma membrane together with a random occurrence of exocytotic figures were observed.Supported by a grant from the Deutsche Forschungsgemeinschaft, Bonn-Bad Godesberg (SFB 122, project C 5). Dedicated to Professor Dr. Gerhard Petry, Marburg, on the occasion of his 65th birthday  相似文献   
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