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The intraperitoneal injection of Balb/c mice with synthetic analogues of adjuvants S-[2,3-bis(palmitoyloxy)-(2-RS)-propyl]-N-palmitoyl-R-cysteine (Pam3Cys) or muramyltripeptide phosphatidylethanolamine (MTP-PE) inhibited the tumourigenic growth of subcutaneously injected VLM cells, a syngeneic simian virus 40 (SV40)-transformed cell line. Furthermore, the Pam3Cys conjugate of K698-T708 (KT), which represents the C-terminal undecapeptide of the SV40 large tumour (T) antigen, was tumour-protective. Also syngeneic spleen cells, preincubated in vitro with this Pam3Cys-KT derivative, which anchores spontaneously at the cell membrane, were, through SV40 tumour mimicry, tumour-protective. The protection was impaired by treatment of the mice with either anti-CD4, anti-CD8 IgG, anti asialo GM1 antiserum or dextrane sulfate, which deplete the CD4+, CD8+ and NK cells or the macrophages, respectively. In summary, SV40 tumour transplantation resistance can be experimentally elicited by a tumour-epitope-specific vaccine. In the absence of an immunogenic epitope protection was obtained by administration of biological response modifiers. Protection is effected by SV40-T-antigen-specific cytotoxic lymphocytes in cooperation with NK cells and macrophages.  相似文献   
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Several radioecological experiences with isotopes of ruthenium, iodine, caesium and barium, obtained after the reactor accident of Chernobyl, are reported. It was found that for a wet deposition barium was the element with the highest retention on grass. The retention of caesium was lower by a factor of 1.6, retention of iodine by a factor of 2.4 and retention of ruthenium by a factor of 3.5. Former data on the caesium transport in cereals from leaves to grain were confirmed. Depending on the conditions the iodine transfer factor for milk varied between 0.002 and 0.007 d.kg-1. The caesium transfer factor for milk was (0.003 +/- 0.0006) d.kg-1 and was found to be relatively constant in the years 1986-1988. In 1991, the values were higher by a factor of 2-5. Radioecological model results of whole-body burdens in Southern Bavaria showed a reduction of the caesium ingestion doses due to countermeasures and spontaneous changes of consumption habits in the first 2 months by a factor of 5 and till the end of 1987 by a factor of 1.5. The model results agree well with the range of measured whole-body burdens. One month after the deposition, the external exposures in urban environments due to ruthenium, caesium and barium isotopes were found to be reduced by a factor of 2, compared with open lawns, in the case of iodine the reduction was even a factor of 2.5. External exposures of a population group from the Munich area were determined by thermoluminescence dosimetry. The results are in accordance with the spectral measurements of external dose rates in urban environments.  相似文献   
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Traumatic vertebral artery injuries are relatively rare. Until recently, insufficient neurodiagnostic technology and a lack of normative data for the population of USAF aviators prevented recommending flying waivers following such vascular injuries. We report the case of an aviator who experienced a traumatic right vertebral artery occlusion with distal embolization. Timely access to a state-of-the-art neurodiagnostic evaluation, which included time-of-flight magnetic resonance angiography (MRA), and standard contrast angiography, provided anatomic imaging at the time of injury and during the recuperative period. Sophisticated neurologic testing protocols at the Armstrong Laboratory's Aeromedical Clinical Sciences Division, Brooks Air Force Base, TX, assessed in-depth this individual's functional status. Consult Service evaluators then compared his performance data with current data in the Head Injury Study in Aviators (HISA) data base. MRA, in comparison with standard contrast angiography, demonstrated anatomic stability of his vascular and neurologic lesions. He demonstrated a functional capacity consistent with normal neurologic functioning in aviators which permitted recommending an occupational (flying) waiver. This case exemplified application of sophisticated ACS neurologic testing protocols to aeromedical evaluations and the use of MRA technology as a vascular screening tool during medical followup.  相似文献   
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We have performed linkage analysis in a small family with autosomal dominant inheritance of multiple café-au-lait spots (CLS) in order to clarify its relationship to classical von Recklinghausen disease (NF 1). We found that an affected woman had transmitted a different haplotype for markers flanking the NF1 gene to both of her affected daughters. These results exclude an allelic mutation of the NF 1 gene on chromosome 17 as the cause for inherited café-au-lait spots in this family.  相似文献   
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