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71.
Background. A single deep inspiration (DI) is known to be a potent bronchodilator but it is not known if repeated DI can accelerate sustained recovery from bronchoconstriction. Methods. We induced sustained bronchoconstriction using increasing concentrations of nebulized methacholine (Mch) during tidal breathing and assessed airway narrowing by measuring respiratory resistance (Rrs) using forced oscillation in six healthy subjects. On separate days we examined the effects of DI every 3 minutes and of prohibition of DI on recovery of Rrs for 30 minutes after the end of Mch nebulization. Results. Bronchoconstriction (Rrs ∼ 150% above baseline) was induced. DI during recovery had a transient bronchodilator effect but no cumulative effect. At 30 minutes after end of nebulization (and 2 minutes after the last DI) Rrs was 87% above baseline compared to 93% above baseline when DI was prohibited. Conclusion. Recovery from induced bronchoconstriction with methacholine was slow (∼ 2%/min) and not accelerated by frequent DI.  相似文献   
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This paper provides new evidence on the degree of income-related inequality in self-assessed health in Belgium. First of all, we combine the time dimension, which has been shown to be very important in the analysis of inequality, and the use of the recently developed interval regression approach to transform a categorical health variable in a continuous one. Second, we measure how the long-run inequality differs from the short-run inequality. Finally, we decompose this health-related income mobility index as well as the long-run concentration index (CI) itself into its contributors. Using data from the panel survey of Belgian households (1994–2002), we find that health is pro-rich distributed and that its inequality is underestimated by 9.45% when neglecting the dynamics of individuals over time. Income, education, job status and age are the most important contributors in the CI and the difference between the short-run and long-run inequality.   相似文献   
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The immunomodulating 2-cyanaziridine derivatives BM 12.531 (azimexone) and BM 41.332 have no effects on the total amount of T-lymphocytes in the spleen of mice but ingrease dose-dependently the percentage of Ly1--, 2+, 3+ T-lymphocytes (killer/suppressor) and decrease the percentage of Ly1+, 2--, (helper) cells. These investigations were carried out by means of specific monoclonal antibodies and fluoreqcence-activated cell sorting. The increase in Ly2+-cells is mainly due to increased suppressor activity.  相似文献   
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This paper examines delinquency as it relates to family influences.  相似文献   
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Methyl sulphone metabolites of PCB and DDE were isolated from different tissues of a Baltic grey seal (Halichoerus grypus). Main components in the seal blubber were identified as 3-MeSO2-2,2',4',5,5'-pentaCB, 4-MeSO2-2,2',4',5,5'-pentaCB, 3-MeSO2-p,p'-DDE, 4-MeSO2-2,2',3',4',5-pentaCB and 4-MeSO2-2,2',3,4',5',6-hexaCB. Liver and lung in the seal contained different MeSO2-PCB pattern compared to all other tissues. These levels in the both tissues were estimated to be 28 and 15 ppm (lipid basis) which corresponded to the same level as the PCB. Concentrations of MeSO2-PCB in any tissues of a Yusho patient were low compared to those in the seal.  相似文献   
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