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61.
H Simon L Stinus M Le Moal 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,290(3):255-258
The acquisition of the intravenous self-administration of d-amphetamine was studied after separate lesions of anterior raphe nuclei (dorsal or median). Every lever-press delivered 2.5 microliter of a d-amphetamine solution dosed at 7.5 microgram/kg. Lesion of anterior raphe nuclei produced an hyper-sensitivity to d-amphetamine as indicated by a dramatic increase in self-administration by experimental Rats compared to the controls. Moreover this enhanced self-administration behavior is observed with a low blood concentration of d-amphetamine. The greater increase was obtained for median raphe lesioned Rats. These effects are interpreted in terms of 5HT-DA balance and could provide an experimental model for neurobiological bases of drug addiction studies. 相似文献
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A. Dobozy L. Kemény M. Csató J. Hunyadi A. Sz. Kenderessy N. Simon 《Cellular and molecular life sciences : CMLS》1984,40(12):1403-1404
Summary An enhancement effect of mouse erythrocyte rosette forming (MERF) cells on the production of migration inhibitory factor, chemotactic factor for neutrophils and skin reactive factor in T-lymphocyte cultures stimulated with the purified protein derivative of tuberculin was observed. We consider it likely that the MERF cells, possessing the appropriate cell surface constituents to construct an immunogenic moiety, present antigen on their surfaces to elicit lymphokine production.This work was supported by the Scientific Research Council, Ministry of Health, Hungary, Code No. 421030401 1/s 相似文献
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Zarnecki JC Leese MR Hathi B Ball AJ Hagermann A Towner MC Lorenz RD McDonnell JA Green SF Patel MR Ringrose TJ Rosenberg PD Atkinson KR Paton MD Banaszkiewicz M Clark BC Ferri F Fulchignoni M Ghafoor NA Kargl G Svedhem H Delderfield J Grande M Parker DJ Challenor PG Geake JE 《Nature》2005,438(7069):792-795
The surface of Saturn's largest satellite--Titan--is largely obscured by an optically thick atmospheric haze, and so its nature has been the subject of considerable speculation and discussion. The Huygens probe entered Titan's atmosphere on 14 January 2005 and descended to the surface using a parachute system. Here we report measurements made just above and on the surface of Titan by the Huygens Surface Science Package. Acoustic sounding over the last 90 m above the surface reveals a relatively smooth, but not completely flat, surface surrounding the landing site. Penetrometry and accelerometry measurements during the probe impact event reveal that the surface was neither hard (like solid ice) nor very compressible (like a blanket of fluffy aerosol); rather, the Huygens probe landed on a relatively soft solid surface whose properties are analogous to wet clay, lightly packed snow and wet or dry sand. The probe settled gradually by a few millimetres after landing. 相似文献
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Interest in mapping the global distribution of malaria is motivated by a need to define populations at risk for appropriate resource allocation and to provide a robust framework for evaluating its global economic impact. Comparison of older and more recent malaria maps shows how the disease has been geographically restricted, but it remains entrenched in poor areas of the world with climates suitable for transmission. Here we provide an empirical approach to estimating the number of clinical events caused by Plasmodium falciparum worldwide, by using a combination of epidemiological, geographical and demographic data. We estimate that there were 515 (range 300-660) million episodes of clinical P. falciparum malaria in 2002. These global estimates are up to 50% higher than those reported by the World Health Organization (WHO) and 200% higher for areas outside Africa, reflecting the WHO's reliance upon passive national reporting for these countries. Without an informed understanding of the cartography of malaria risk, the global extent of clinical disease caused by P. falciparum will continue to be underestimated. 相似文献
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Résumé La microscopie électronique a permis d'observer des lésions du glomérule et du tube proximal, après administration intraveineuse d'inuline chez les lapins: nombreux macrophages dans les anses glomérulaires, tuméfaction endothéliale, tuméfaction épithéliale avec soudure des pédicelles; nécrose des cellules épithéliales du tube proximal.La poursuite de cette étude devrait établir définitivement si l'emploi de l'inuline est contre-indiqué dans l'exploration fonctionnelle rénale. 相似文献