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61.
Eight flavonoid C-glycosides, including three new analogues, have been isolated from leaf and root methanolic extracts of Petrorhagia velutina, a Mediterranean herbaceous plant. The antiproliferative activity against human hepatoblastoma cancer cell line HepG2 has been analyzed by the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) test. Isoorientin (4) significantly reduces the proliferation of HepG2 cells as determined by the complete conversion of the tetrazolium probe into formazan after 48 h of exposure.  相似文献   
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The ultrastructural characterization of the present continuous cell line, derived from a primary ductal infiltrating carcinoma (d.i.c.) of the human breast, has brought to light a remarkable morphological similarity with the original neoplastic cell population. A major parallelism is the permanent presence in culture of two categories of cells, exhibiting a strong isomorphism with the in vivo counterparts. The presence of well defined ultrastructural features, as duct-like structures, microvillous projections, junctional complexes and intracytoplasmic crypts, is a further confirmation of the breast cancer origin of this line. The significance and perspective of these findings are discussed.  相似文献   
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Defects attributable to drug therapy represent about 1% of congenital defects of known aetiology. This means that a precautionary attitude and correct use of drugs in fertile, and especially pregnant, women is a feasible form of prevention. Drugs currently in use with proven teratogenic effect number approximately 25, but new pharmaceutical drugs are constantly in preparation. Recognition of a drug-induced teratogenic effect is a complex procedure taking into account not only experimental animal data but also experience in humans. Considering that 40% of pregnancies are not planned, it follows that any drug with known or suspected teratogenic potential must be used only under strict medical control. Also, adequate knowledge on potential teratogenicity of a drug permits modification of therapy before conception. It goes without saying that any drug should be used during pregnancy only if it is essential, and it would be prudent to use only those where adequate information is provided and prior clinical experience is available. Teratology Information Services can assist both physicians and patients when any doubt exists.  相似文献   
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Interferon (IFN)-alpha with or without ribavirin is the treatment of choice for patients with chronic HCV-related hepatitis. Cough and dyspnea during IFN therapy are often regarded as a side effect and not as a possible sign of the onset of a pulmonary interstitial disease. It may therefore be claimed that the likelihood that patients treated with IFN develop sarcoidosis is being underestimated. Although they are not conventionally classified as etiopathologic agents of sarcoidosis, the IFNs have been proven to be capable of triggering macrophages and of promoting the expression of class II HLA antigens. It is therefore possible that IFN-alpha treatment could trigger macrophages and promote the polarization of the immune response towards Th1 in the presence of particular susceptibility conditions, thus starting the series of events that lead to the onset of sarcoidosis. We describe a case of pulmonary sarcoidosis in a 33-year-old patient treated with IFN-alpha2b and ribavirin for chronic HCV-related hepatitis after 6 months of therapy. The case we report here brings forth the issue of a possible underestimation of the real incidence of sarcoidosis during IFN therapy and highlights the need for more attention to and a more careful evaluation of respiratory symptoms manifesting in treated patients.  相似文献   
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Epitope mapping of Grapevine virus A capsid protein   总被引:2,自引:0,他引:2  
Summary.  Previously characterized monoclonal antibodies (MAbs) to Grapevine virus A (GVA) showed a differential reactivity against intact or partially destabilized virus particles [2]. In the present study, this differential reactivity was confirmed and several peptides reacting with a panel of four different antibodies were identified by the PEPSCAN method of epitope mapping. Oligopeptide sequences comprised between coat protein residues 61 (V) and 72 (T) were recognized by all the antibodies tested. One of these peptides (VGPKASK) was also reactive when expressed on recombinant phage particles as a fusion protein with protein pVIII. The specificity of this sequence for antibody binding was also demonstrated by competitive-ELISA using one of the GVA MAbs. The results of this study suggest that GVA particles carry a highly structured epitope centered on a common peptide region of the coat protein sequence. Received June 5, 2001 Accepted October 26, 2001  相似文献   
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