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In open chest dogs myocardial ischemia was induced by formation of an occlusive thrombus in the left anterior circumflex artery (LCX). Reperfusion of the LCX was achieved by infusion of the fibrin specific recombinant single-chain urokinase-type plasminogen activator (r-scu-PA). The myocardial salvage by r-scu-PA alone and in combination with the epoprostenol (prostacyclin) analog taprostene (CG 4203) was compared. There were four experimental groups: group 1 (n = 4) did not receive any treatment after LCX thrombosis; in group 2 (n = 9) at 100 min after LCX thrombosis r-scu-PA (20 micrograms.kg-1.min-1 i.v. for 30 min) was infused; in groups 3 and 4 treatment with taprostene started concomitantly with r-scu-PA infusion. The taprostene infusions lasted for 120 min and the doses were 0.1 microgram.kg-1.min-1 in group 3 (n = 6) and 0.215 microgram.kg-1.min-1 in group 4 (n = 6). Time to r-scu-PA-induced recanalisation ranged from 18-22 min with no significant difference between groups 2-4. Percent of left ventricle at risk did not differ between the groups. Infarct size as percent of the risk zone was 48.3 +/- 7.7 in group 1, 25.3 +/- 3.7 in group 2, 21.3 +/- 6.5 in group 3 and 17.1 +/- 3.5 in group 4 (p less than 0.05 groups 2-4 vs group 1). Incidence of ectopic beats increased after r-scu-PA-induced reperfusion in groups 2-4, but was significantly reduced by taprostene.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Object: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant. Its analysis is done by combustion in an oven and determination of the CO2 formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows determination of both fractions of the soot: “elemental carbon” (EC) and organic carbon␣(OC). The sum of EC and OC is called TC (total carbon). Method: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading was 2.5 to 150 μg/cm2 of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample. Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories. It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. Results: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around 10% to 15% for EC above about 20 μg/cm2. Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether the “environmental” laboratories give different results from the “occupational” laboratories, but it is clear that their objectives differ since for the “environmentalists”, EC is not a specific marker of diesel immissions, in contrast to the “occupationalists”. Conclusion: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot. Received: 30 December 1996 / Accepted: 21 February 1997  相似文献   
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In 1968, Koppitz described the human figure drawings of 5- to 12-year-old children and established normative data for these age groups. The present work consisted of two parts. The first confirmed the observations of Koppitz to a very considerable degree in a sample of predominantly middle-class, White children between 5 and 7 years of age. Concordance was observed by employing Koppitz's categorization schema of Expected, Common, Not Unusual, and Exceptional items by males and females. The second aspect of the work examined the drawings of 3- and 4-year-old children utilizing Koppitz's categories.  相似文献   
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Monoclonal antibody MAB-T88 is a human monoclonal immunoglobulin M antibody directed at the lipopolysaccharide of gram-negative bacteria. In this study, nine patients who were expected to become neutropenic from antineoplastic chemotherapy received an infusion of MAB-T88, three patients at each of three doses: 1, 4, and 8 mg/kg of body weight. MAB-T88 was shown to be safe, with an effective half-life in plasma of 25.4 h, and no patient developed immunoglobulin G antibody to MAB-T88.  相似文献   
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Acute actions of MPTP on behavior and on neostriatal ultrastructure were examined in young C57 Black mice. Autonomic, motor, and toxic effects of MPTP exhibited dependence on dose (20-40 mg/kg) and time during the first 4 h after subcutaneous injection. The ultrastructure of the neostriatum was altered very quickly (2-24 h) after single injections of MPTP. Darkened glial processes were found within 2-8 h, followed by dark degeneration of synaptic boutons, especially those making small symmetric synapses. More rarely, swollen axons and postsynaptic degeneration were also observed.  相似文献   
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P L Groves  M H Pech  A B Troutt    A Kelso 《Immunology》1994,83(1):25-32
Although cytokine-producing T cells play a key role in the response to vaccination, they are not always revealed by antigen stimulation of primed lymphoid cells in vitro. In this study, mice were immunized subcutaneously with alum-precipitated keyhole limpet haemocyanin (KLH) in adjuvant to activate interleukin-4 (IL-4)-producing CD4+ T cells. IL-4 mRNA was the dominant cytokine mRNA species found in draining lymph nodes (LN) 7 days after immunization and its levels were increased after in vitro stimulation with KLH for 24 hr. IL-4 protein, on the other hand, was not detected in the supernatants of such antigen-stimulated cultures. The presence of T cells primed for IL-4 production was nevertheless suggested by the findings that primed LN cells produced low IL-4 titres in response to anti-CD3 antibody, whereas normal LN cells did not, and primed CD4+ LN cells produced readily detectable IL-4 levels in response to antigen after one or more cycles of in vitro restimulation. Culture at limiting dilution showed that 1-2% of 7 day KLH-primed CD4+ LN cells were clonogenic and specific for KLH without prior expansion in vitro, and that this frequency was markedly increased by repeated stimulation in bulk culture. Most clonogenic cells in primed LN gave rise to IL-4-secreting clones and a smaller number gave rise to interferon-gamma (IFN-gamma)-producing clones. The precursor frequency of IL-4-producing CD4+ cells in primed LN and the average IL-4 titre per cloned cell support the conclusion that these two parameters account for the low levels of IL-4 produced in bulk culture by LN cells from immunized mice.  相似文献   
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