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1.
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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3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
4.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
8.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
9.
M. Guillemin H. Cachier C. Chini D. Dabill D. Dahmann F. Diebold A. Fischer H.-H. Fricke J. A. Groves R. Hebisch M. Houpillart G. Israël M. Mattenklott W. Moldenhauer J. P. Sandino C. Schlums E. Sutter E. Tucek 《International archives of occupational and environmental health》1997,70(3):161-172
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
10.