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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
982.
U. Ravens Michael O. Flüß Q. Li Herbert M. Himmel Erich Wettwer Michael Klockow Inge Lues 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(6):733-742
The thiadiazinone derivative [+]-EMD 60263 ((+)-5-(1-(α-ethylimino-3,4-dimethoxybenzyl)-1,2,3,4- tetrahydroquinoline-6-yl)-6-methyl-3,6-dihydro-2H-1,3,4
-thiadiazine-2-on) is a Ca2+-sensitizing agent with only minor phosphodiesterase inhibitory activity. Our aim was to characterize the inotropic and electrophysiological
effects of [+]-EMD 60263 and its enantiomer [-]-EMD 60264 in several cardiac muscle preparations. The Ca2+-sensitizing activity resided in the [+]-enantiomer only. [+]-EMD 60263 (3 μM) shifted the EC50 of Ca2+ for contractile activation of skinned fibers of pig heart from 2.41 μM to 0.73 μM, whereas [-]-EMD 60264 (30 μM) was ineffective.
In Langendorff-perfused guinea pig hearts, [+]-EMD 60263 and [-]-EMD 60264 induced concentration-dependent positive and negative
inotropic effects, respectively; both enantiomers reduced spontaneous heart rate but did not influence perfusion pressure.
The maximum increase in force of human atrial trabeculae was 35 % of pre-drug control with [+]-EMD 60263 in comparison to
113 % with forskolin. In guinea-pig papillary muscles, [+]-EMD 60263 and [-]-EMD 60264 had opposite inotropic responses, however,
both agents similarly prolonged action potential duration. Both enantiomers concentration-dependently blocked the rapidly
activating component IKr of the delayed rectifier in guinea-pig myocytes. The block saturated at potentials positive to +30 mV, closely resembling
the effects of the antiarrhythmic agent E-4031 which had been originally used to define IKr. It is concluded, that the positive inotropic action of [+]-EMD 60263 can be explained by prevalence of the Ca2+-sensitizing effect. The accompanying prolongation in action potential duration is caused by block of the IKr component of the delayed rectifier. While the inotropic effects are stereoselective, most of the electrophysiological actions
are clearly independent of sterical configuration. The combination of Ca2+-sensitizing with class-III antiarrhythmic action may provide an interesting pharmacological profile of potential therapeutic
use.
Received: 7 January 1997 / Accepted: 25 February 1997 相似文献
983.
J.-P. Coudereau Marcel Debray Claire Monier Jean-Marie Bourre Henriette Frances 《Psychopharmacology》1997,130(2):117-123
Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation
(15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine
(8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg).
Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance
of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing
learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and
passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice
regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and
retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment
in isolated mice.
Received: 10 April 1996 /Final version: 20 September 1996 相似文献
984.
Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
985.
H. Nilsson J. Johansson K. Svanberg S. Svanberg G. Jori E. Reddi A. Segalla D. Gust A. L. Moore T. A. Moore 《British journal of cancer》1997,76(3):355-364
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated. 相似文献
986.
A wound, in the broadest sense, is a disruption of normal anatomic structure and function. Acute wounds progress through a timely and orderly sequence of repair that leads to the restoration of functional integrity. In chronic wounds, this timely and orderly sequence goes awry. As a result, people with chronic wounds often face not only physiological difficulties but emotional ones as well. The study of body image and its damage as a result of a chronic wound fits well with Selder's transition theory. This article describes interviews with seven patients with chronic wounds. The themes that emerged from those interviews were compared with Selder's theory to describe patients' experience with chronic wounds as a transition process that can be identified and better understood by healthcare providers. 相似文献
987.
988.
989.
990.
K. Reynen U. Röber W.G. Daniel R. Henßge S. Schüler 《Clinical research in cardiology》1998,87(5):331-335
Zusammenfassung Zahlen zur H?ufigkeit von Herztumoren im operativen Krankengut liegen bisher für die Bundesrepublik Deutschland nicht vor.
Um einen entsprechenden überblick für das Jahr 1996 zu erhalten, wurde allen 77 herzchirurgischen Zentren der Bundesrepublik
Deutschland ein standardisierter Fragebogen zugesandt.
Daten von 65 der 77 Herzzentren (=84%) waren schlie?lich verfügbar: 187 Patienten waren wegen Myxomen, lediglich 44 wegen
nichtmyxomat?sen Tumoren, davon 28 wegen malignen prim?ren oder sekund?ren Herztumoren, operiert worden. Im Jahr 1996 waren
somit 0,32% (231/72 763) der Eingriffe mit Herz-Lungen-Maschine (erfa?t 72 763 von insgesamt 87 372) wegen eines Herztumors
vorgenommen worden. Ausgehend von diesen operativen Daten liegt die Inzidenz ausschlie?lich der prim?ren Tumoren des Herzens
zumindest bei 3 Tumoren pro 1 Million Einwohner pro Jahr (253 Tumoren/81,814 Millionen Einwohner). Wenn auch kleine Tumoren
asymptomatisch und unentdeckt bleiben k?nnen, wird heute doch die Mehrzahl prim?rer kardialer Tumoren durch Echokardiographie,
Computer- und Kernspintomographie bereits zu Lebzeiten des Patienten diagnostiziert, und diese Patienten werden in aller Regel
einer Operation zugeführt.
Somit werden gut 0,3% aller Eingriffe mit Herz-Lungen-Maschine in Deutschland wegen Herztumoren durchgeführt, wobei es sich
weit überwiegend um Myxome handelt.
Eingegangen: 23. September 1997, Akzeptiert: 11. Februar 1998 相似文献