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61.
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Thin films (thickness 0,3 μm) of a mixture of phthalocyaninatozinc(II) ( 1 ) and poly(1-vinylcarbazole) ( 2 ) are prepared by coating from a solution on ITO glass. The blue coloured films are investigated in an electrochemical cell under irradiation with visible light. In the presence of dioxygen from air the films exhibit an intensive cathodic photocurrent. The action spectrum of the photocurrent corresponds to the absorption spectrum of the phthalocyanine. The results show a device which can be switched by air and visible light.  相似文献   
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A rare case of malignant lymphoma of the adrenal gland in a 68-year-old male is reported. Autopsy revealed bilateral and symmetrical adrenal tumors (lt: 54 g, rt: 39 g) and almost complete effacement of both adrenal glands, while no tumors were present in other organs or systemic lymph nodes. Both adrenal tumors histologically presented a picture of diffuse malignant lymphoma of mixed cell type. Microscopic involvement in both lungs, spleen, liver, lymph node, bone marrow and both kidneys was found. Immunohistochemically, the positive reactions shown by the lymphoma cells were of B cell type, i.e., observed using antibodies to the leukocyte common antigens, MB-1, LN-1, LN-2 and LN-3, but not by anti-factor VIII-related antigen or MT-1. Examination of peripheral blood obtained just before the patient died showed the presence of 18% atypical cells. This lymphoma was considered to have transformed to a leukemic phase, at least at the end stage. To the author's knowledge, this is the second case of primary adrenal lymphoma to be reported in Japan, and the first case showing formation of bilateral and symmetrical tumors.  相似文献   
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Osteopenia is a recognized complication of diabetes mellitus in humans and experimental animals. We recently found that tetracyclines prevent osteopenia in the streptozotocin-induced diabetic rat and that this effect was associated with a restoration of defective osteoblast morphology (Golub et al., 1990). The present study extends these initial ultrastructural observations by assessing osteoblast function in the untreated and tetracycline-treated diabetic rats. After a 3-week protocol, non-diabetic control and diabetic rats, including those orally administered a tetracycline, minocycline (MC), or a non-antimicrobial tetracycline analog (CMT), were perfusion-fixed with an aldehyde mixture; the humeri were dissected and processed for ultracytochemical localization of alkaline phosphatase (ALPase) and Ca-ATPase activities. Some rats from each experimental group received an intravenous injection of 3H-proline as a radioprecursor of procollagen, and the humeri were processed for light microscopic autoradiography. In addition, the osteoid volume in each experimental group was quantitatively examined by morphometric analysis of electron micrographs. During the diabetic state, active cuboidal osteoblasts in the endosteum of control rats were replaced by flattened bone-lining cells that contained few cytoplasmic organelles for protein synthesis (Golgi-RER system), and active transport (mitochondria). Treating diabetic rats with MC, and even more so with CMT, appeared to "restore" osteoblast structure. During diabetes, bone-lining cells incorporated little 3H-proline or secreted little labeled protein and produced only a very thin osteoid layer. Tetracycline administration to the diabetics increased both the incorporation of 3H-proline by osteoblasts and their secretion of labeled protein toward the osteoid matrix, in a pattern similar to that seen in the non-diabetic controls.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc.  相似文献   
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This study aims to resolve a paradox. Experiments measuring alpha band power report an event related decrease (desynchronization) in alpha activity, whereas those measuring evoked alpha report synchronization. During a recognition memory task with human subjects, we measured the evoked (phase locked) and induced (not phase locked) alpha response. The findings reveal that evoked alpha is due to a transient phase locking (at about 100-200 ms poststimulus) of three alpha sub-bands which can be observed only at parieto-occipital sites. In contrast, induced alpha shows a widespread pattern of desynchronization at most recording sites. Thus, opposite alpha responses occur within similar time windows. Evoked alpha synchronization may reflect cortical inhibition which serves to increase the signal to noise ratio for activation processes following immediately later.  相似文献   
70.
In order to investigate the mechanism of urinary tract stone formation, we analyzed protein components in urine and the stone. Urinary proteins of healthy subjects and urolithic patients as well as protein components urinary tract stone of the urolithic patients were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Electrophoretic patterns of urinary proteins of the patients differed from those of healthy subjects after separating protein patterns into those larger than 66kDa or smaller than 30kDa. Protein constituents of urinary tract stone were mainly separated into 18 bands ranging from 26.8 to 143 kDa. Major bands among these 18 bands differed among stones from different patients. On western blotting, the developed intensities of Tamm-Horsfall protein (THP) were fainter than those of healthy subjects. Whereas intensities of albumin (ALB) were stronger than those of healthy subjects. Moreover, blotting patterns of THP of the patients on non-reducing SDS-PAGE were obviously broad. Thus, we suggest that analysis of fractionated urinary proteins or protein components of urinary tract stone may provide a tool for monitoring the prognosis or relapse in the patients.  相似文献   
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