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Cytogenetic observations were made on 6 cell lines (MOB-1, MOB-2, MOB-3, MSB-1, HPRS Line 1, HPRS Line2) originating from Marek's disease lymphomas and 2 clones (1104-B, 1104-X-5) of a cell line established from an avian lymphoid leukosis tumor. The modal chromosome number was within the diploid range in all the lines except HPRS Line 1 and HPRS Line 2, both of which had a mode at about 60. Karyotypes were grossly abnormal in 4 cell lines: trisomy for No. 1 in MOB-2; the heteromorphic No. 1 pair in MSB-1, and marker chromosomes derived from rearrangements involving No. 3 or No. 5 and unidentified elements in HPRS Lines 1 and 2. The MOB-1 line which had been characterized by cells with an apparently normal karyotype was completely taken over by cells with a heteromorphic No. 1 pair morphologically similar to the one found in MSB-1 by the 95th day of continuous growth in vitro. BUdR-acridine orange differential staining technique revealed, however, different banding patterns in these abnormal chromosomes.  相似文献   
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The T-cell surface antigens on three lymphoblastoid cell lines, MOB1, MOB-2 and MSB-1, derived from Marek's disease lymphomas were examined by the cytotoxicity test and the indirect membrane immunofluorescent test. These cell lines reacted specifically with antisera prepared against chicken thymus cells, although their reactivities were less than that of typical thymus cells. These three cell lines were of thymus origin.  相似文献   
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Disconnected (disco)-interacting protein 2 homolog A is a member of the DIP2 protein family encoded by Dip2a gene. Dip2a expression pattern has never been systematically studied. Functions of Dip2a in embryonic development and adult are not known. To investigate Dip2a gene expression and function in embryo and adult, a Dip2a-LacZ mouse model was generated by insertion of β-Gal cDNA after Dip2a promoter using CRISPR/Cas9 technology. Dip2a-LacZ mouse was designed to be a lacZ reporter mouse as well as a Dip2a knockout mouse. Heterozygous mice were used to study endogenous Dip2a expression and homozygotes to study DIP2A-associated structure and function. LacZ staining indicated that Dip2a is broadly expressed in neuronal, reproductive and vascular tissues, as well as in heart, kidney, liver and lung. Results demonstrate that Dip2a is expressed in ectoderm-derived tissues in developing embryos. Adult tissues showed rich staining in neurons, mesenchymal, endothelial, smooth muscle cells and cardiomyocytes by cell types. The expression pattern highly overlaps with FSTL1 and supports previous report that DIP2A to be potential receptor of FSTL1 and its protective roles of cardiomyocytes. Broad and intense embryonic and adult expression of Dip2a has implied their multiple structural and physiological roles.  相似文献   
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Few prospective studies support the use of anticoagulation during the acute phase of ischemic stroke, though observational data suggest a role in certain populations. Depending on the mechanism of stroke, systemic anticoagulation may prevent recurrent cerebral infarction, but concomitantly carries a risk of hemorrhagic transformation. In this article, we describe a case where anticoagulation shows promise for ischemic stroke and review the evidence that has discredited its use in some circumstances while showing its potential in others.  相似文献   
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This study investigated the exposure of jaguar populations and domestic animals to smooth Brucella, Leptospira spp. and Toxoplasma gondii in the Cerrado, Pantanal and Amazon biomes of Brazil. Between February 2000 and January 2010, serum samples from 31 jaguars (Panthera onca), 1,245 cattle (Bos taurus), 168 domestic dogs (Canis lupus familiaris) and 29 domestic cats (Felis catus) were collected and analysed by rose bengal test for smooth Brucella, microscopic agglutination test for Leptospira spp. and modified agglutination test for T. gondii. Cattle populations from all sites (9.88%) were exposed to smooth Brucella, but only one jaguar from Cerrado was exposed to this agent. Jaguars captured in the Cerrado (60.0%) and in the Pantanal (45.5%) were seropositive for different serovars of Leptospira spp., cattle (72.18%) and domestic dogs (13.1%) from the three sites and one domestic cat from Pantanal were also seropositive for the agent. The most prevalent serotype of Leptospira spp. identified in jaguars from the Cerrado (Grippotyphosa) and the Pantanal (Pomona) biomes were distinct from those found in the domestic animals sampled. Jaguars (100%), domestic dogs (38.28%) and domestic cats (82.76%) from the three areas were exposed to T. gondii. Our results show that brucellosis and leptospirosis could have been transmitted to jaguars by domestic animals; and jaguars probably play an important role in the maintenance of T. gondii in nature.  相似文献   
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Serial passages in culture of herpesvirus of turkeys resulted in structural genomic changes at the regions common to two virus strains with loss of their protective ability against Marek's disease.  相似文献   
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