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81.
Novel compounds having a dual pharmacophore were synthesised and evaluated for their insulin sensitiser and anti-inflammatory properties in different animal models.  相似文献   
82.
This is a case report of a 43-year-old woman who received a transplant for end-stage liver disease due to hereditary hemorrhagic telangiectasia and fibropolycystic liver disease. This is an uncommon association of two autosomal-dominant conditions with defined genetic and molecular defects. The liver showed extensive vascular malformations of arteries and veins as well as telangiectasia and fibrosis. In addition, there were cystically dilated ducts containing inspissated bile and extensive von Meyenburg complexes. This case raises interesting questions about the possible relationship of these genes and their gene products, both of which are related to cell-matrix interactions and are strongly associated with blood vessels, one of them being expressed on endothelial cells and the other being developmentally important in blood vessels.  相似文献   
83.
84.
Soft-tissue augmentation using the synthetic nonfluid biomaterial expanded polytetrafluoroethylene (ePTFE) has been supported by number of recent reports citing the favorable characteristics of biocompatibility, soft and natural feel, ease of use, and permanent augmentation. Concern has been expressed about this application for ePTFE material because of the proximity of the implants to the skin surface and potential problems with infection and extrusion. We evaluated the behavior of a series of specific ePTFE implant designs using a long-term subcutaneous augmentation model. By using a porcine model, 466 implants of ePTFE in the form of strips, rolls, or tubes were placed using a percutaneous insertion device subcutaneously over the dorsum and face. The animals were divided into three study groups by length of implantation (3 weeks, control; 6 months, intermediate term; and 12 months, long-term) and en-bloc tissue specimens, including skin, implants, and underlying soft tissue, were harvested for gross and histologic examination. Implants were removed at the earliest sign of infection, exposure, or extrusion and the difficulty of removal was ascertained and recorded. These data reveal that ePTFE material elicits acceptable levels of tissue activity with low extrusion rates over the short and long term supporting its use for soft-tissue augmentation. The data show a clear difference, however, in the host response and behavior of the implants for this application based on shape or design. A statistically significant difference in the low, but measurable, extrusion rates was observed amongst these implant designs. ePTFE tubes showed greater stability and predictable augmentation over other implant designs for soft-tissue augmentation and seem to represent a substantial improvement for this application.  相似文献   
85.
Autoimmune polyglandular disease type I (APECED) is an autosomal recessive autoimmune disease (MIM 240300) characterized by hypoparathyroidism, primary adrenocortical failure, and chronic mucocutaneous candidiasis. The disease is highly prevalent in two isolated populations, the Finnish population and the Iranian Jewish one. Sporadic cases have been identified in many other countries, including almost all European countries. The APECED locus has previously been assigned to chromosome 21q22.3 by linkage analyses in 14 Finnish families. Locus heterogeneity is a highly relevant question in this disease affecting multiple tissues and with great phenotypic diversity. To solve this matter, we performed linkage and haplotype analyses on APECED families rising from different populations. Six microsatellite markers on the critical chromosomal region of 2.6 cM on 21q22.3 were analyzed. Pairwise linkage analyses revealed significant LOD scores for all these markers, maximum LOD score being 10.23. The obtained haplotype data and the geographic distribution of the great-grandparents of the Finnish APECED patients suggest the presence of one major, relatively old mutation responsible for approximately 90% of the Finnish cases. Similar evidence for one founder mutation was also found in analyses of Iranian Jewish APECED haplotypes. These haplotypes, however, differed totally from the Finnish ones. The linkage analyses in 21 non-Finnish APECED families originating from several European countries provided independent evidence for linkage to the same chromosomal region on 21q22.3 and revealed no evidence for locus heterogeneity. The haplotype analyses of APECED chromosomes suggest that in different populations APECED is due to a spectrum of mutations in a still unknown gene on chromosome 21.  相似文献   
86.
We previously showed that vaccinia virus infection of BSC40 cells was blocked by soluble heparin, suggesting that cell surface heparan sulfate mediates vaccinia virus binding (C.-S. Chung, J.-C. Hsiao, Y. -S. Chang, and W. Chang, J. Virol. 72:1577-1585, 1998). In this study, we extended our previous work and demonstrated that soluble A27L protein bound to heparan sulfate on cells and interfered with vaccinia virus infection at a postbinding step. In addition, we investigated the structure of A27L protein that provides for its binding to heparan sulfate on cells. A mutant of A27L protein, named D-A27L, devoid of a cluster of 12 amino acids rich in basic residues, was constructed. In contrast to the soluble A27L protein, purified D-A27L protein was inactive in all of our assays, including binding to heparin in vitro, binding to heparan sulfate on cells, and the ability to block virus infection. These data demonstrated that the N-terminal region acts as a glycosaminoglycan (GAG)-binding domain critical for A27L protein binding to cells. Previously A27L protein was thought to be involved in fusion of virus-infected cells induced by acid treatment. When we investigated whether cell surface GAGs also participate in A27L-dependent fusion, our results indicated that soluble A27L protein blocked cell fusion, whereas D-A27L protein did not. Taken together, the results therefore demonstrated that A27L-mediated cell fusion is triggered by its interaction with cell surface GAGs through the N-terminal domain.  相似文献   
87.
Epidemiology shows a relationship between solar exposure and all types of skin cancer. Understanding the mechanisms of skin cancer requires knowledge of the photomolecular events that occur within the relevant epidermal cell types in vivo. Studies to date have focused on UVR-induced DNA lesions in keratinocytes, the majority epidermal cell population which gives rise to most skin cancers. Malignant melanoma, arising from melanocytes (5%-10% of epidermal cells), accounts for most skin cancer deaths. We report on new techniques to detect DNA photolesions in human epidermal melanocytes in situ. Previously nonexposed buttock skin of volunteers of skin types I/II was exposed to clinically relevant doses of narrow bandwidth UVB (300 nm) and UVA (320 nm, 340 nm, 360 nm) radiation. Biopsies were taken immediately afterwards and processed for routine histology. Microscope sections were prepared and double-stained with fluorescent-tagged monoclonal antibodies for thymine dimers and melanocytes. UVR dose-response curves for dimer levels within melanocyte nuclei were determined by image analysis and compared with dimer levels in adjacent basal cell keratinocytes. Our data show that UVB and UVA readily induce thymine dimers in melanocytes at levels that are comparable with those found in adjacent keratinocytes. This new technique will enable melanocyte specific studies, such as DNA repair kinetics, to be done in vivo.  相似文献   
88.
A microorganism of the genus Pseudomonas has been isolated from the soil by enrichment culture techniques with linalool(I) as the sole source of carbon and energy. The organism is also capable of utilizing limonene, citronellol, and geraniol as substrates but fails to grow on citral, critranellal, and 1,8-cineole. Fermentation of linalool by this bacterium in a mineral salt medium results in the formation of 10-hydroxylinalool(II), oleuropeic acid (IX), 2-vinyl-2-methyl-5-hydroxyisopropyl-tetraphydrofuran)linalool oxide, V), 2-vinyl-2-methyl-tetrahydrofuran-5-one(unsaturated lactone, VI), and few unidentified minor metabolities. Probable pathways for the biodegradation of linalool are presented.  相似文献   
89.
Groups of day-old chicks with varying levels of parental antibody were vaccinated against Newcastle disease (B1 strain) with a commercially available device which simultaneously debeaks the chick and emits a fine spray of vaccine into its trachea. Some groups were also vaccinated (B1 or Lasota strain) with a commercially available vaccine sprayer at 9 days, 14 days, or 9 and 25 days of age. Response to vaccine was evaluated once each week during the experimental period of approximately 8 weeks HI titers were determined and 10 chicks were challenged with the Texas GB strain of Newcastle disease virus. In chicks with low to moderate levels of maternal antibody a satisfactory antibody response was attained by vaccination at 1 day of age, and in most cases resistance to challenge was evident by 3 weeks of age. Intratracheal vaccination of chicks with extremely high levels of maternal antibody had a minimal antibody response. All groups of chicks spray vaccinated at 9, 14, or 9 and 25 days of age showed a marked increase in antibody titer regardless of whether they had been vaccinated at 1 day of age.  相似文献   
90.
A retrospective study of ultrasound images of the liver in patients with hepatitis was undertaken. Two distinct ultrasound patterns were detected. In acute hepatitis, the predominant findings were accentuated brightness and more extensive demonstration of the portal vein radicle walls and overall decreased echogenicity of the liver. Chronic hepatitis primarily revealed decreased brightness and number of portal vein radicle walls and verall increased liver echogenicity. In addition, the pathological severity closely paralleled these ultrasound patterns. A prospective study confirmed the same acute hepatitis ultrasound findings with close correlation to the clinical severity. These distinct ultrasound patterns will help to evaluate patients with suspected acute and chronic hepatitis and more accurately define intrahepatic causes of jaundice.  相似文献   
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