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We have previously described the isolation and characterization of an intact multiprotein complex for DNA replication, designated the DNA synthesome, from human breast cancer cells and biopsied human breast tumor tissue. The purified DNA synthesome was observed to fully support DNA replication in vitro. We had also proposed a model for the breast cell DNA synthesome, in which DNA polymerases alpha, delta, and epsilon, DNA primase, and replication factor C (RF-C) represent members of the core component, or tightly associated, proteins of the complex. This model was based on the observed fractionation, chromatographic, and sedimentation profiles for these proteins. We report here that poly(ADP-ribose)polymerase (PARP) and DNA ligase 1 are also members of the breast cell DNA synthesome core component. More importantly, in this report we present the results of coimmunoprecipitation studies that were designed to map the protein-protein interactions between several members of the core component of the DNA synthesome. Consistent with our proposed model for the breast cell DNA synthesome, our data indicate that DNA polymerases alpha and delta, DNA primase, RF-C, as well as proliferating cell nuclear antigen (PCNA), tightly associate with each other in the complex, whereas DNA polymerase epsilon, PARP, and several other components were found to interact with the synthesome via a direct contact with only PCNA or DNA polymerase alpha. The association of PARP with the synthesome core suggests that this protein may serve a regulatory function in the complex. Also, the coimmunoprecipitation studies suggest that the three DNA polymerases alpha, delta, and epsilon all participate in the replication of breast cell DNA. To our knowledge this is the first report ever to describe the close physical association of polypeptides constituting the intact human breast cell DNA replication apparatus.  相似文献   
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The subjective assessment of scar appearance is a widely used method in the evaluation of burn outcomes and the efficacy of treatment methods. The purpose of this study is to design a numeric scar-rating scale with better interrater reliability than has previously been reported. The rating scale assesses scar surface, thickness, border height, and color differences between a scar and the adjacent normal skin. Eight raters were trained with use of a standardized set of photographs that provide examples of the scores to be assigned to each level of severity of each scar characteristic. The raters then rated 10 photographs of different scars, referring to the teaching set of pictures for comparison. The intraclass correlation (interrater reliability) was 0.94, 0.95, 0.90, and 0.85 for scar surface, border height, thickness, and color, respectively. This rating system has proved to be a useful tool for the evaluation of scar surface, thickness, border height, and color.  相似文献   
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This study is an examination of the task performance patterns of Black and White, working and middle-class American children across a nonvaried and a varied presentation format condition: the relation of such patterns to activity levels in the home and to standardized achievement was also examined. Performance was better under the varied than the nonvaried format condition. This pattern held for all ethnic group/class combinations with the exception of Black middle-class children, for whom performance under the two conditions was virtually identical. Moreover, Black children, especially Black working-class children, reported greater home activity levels than did their White counterparts. Neither home activity level nor achievement was functionally related to patterns of performance.  相似文献   
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Rabbits were immunised with stage 1 and stage 2 soluble haemagglutinins (sHA) of Helicobacter pylori strain NCTC 11637 and with rabbit erythrocytes coated with stage 1 sHA. After adsorption of stage 1 sHA on erythrocytes, SDS-PAGE analysis showed that 4 major protein bands were removed from the preparation. The anti-sHA coated erythrocyte serum had the highest HA inhibition titre of 16. Crossed immunoelectrophoresis of the stage 1 sHA, against stage 1 and 2 antisera showed multiple precipitin arcs; however, the anti-sHA coated erythrocyte serum produced only two arcs. One arc produced by the anti-stage 2 serum was absent with the anti-stage 1 serum. This arc could have been produced against a 20 kDa polypeptide which was absent in the stage 1 sHA. The other arc was stronger when compared with that produced by anti-stage 1 serum. These two arcs corresponded to the two arcs produced by the anti-sHA coated erythrocyte serum, which had the highest inhibition titre. The two arcs were markedly reduced in crossed immunoelectrophoresis with an adsorbed stage 1 sHA preparation, which indicates that these arcs were produced against the sHAs.  相似文献   
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Three-week-old turkeys were injected intravenously with Bordetella avium-specific immunoglobulin G (IgG), and absorbance readings were measured in blood, tracheal washings, and lacrimal secretions using an enzyme-linked immunosorbent assay at various time intervals. IgG was detected in tracheal and lacrimal secretions as early as 5 minutes after injection and peaked at 10 minutes after injection. Thereafter, IgG absorbance declined rapidly, reaching background levels by 24 hours. The absorbance readings of IgG in all three sites were comparable at all times from 10 minutes to 24 hours after administration. The results indicated that movement of IgG from blood to mucosal surfaces in turkeys occurs rapidly.  相似文献   
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