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991.
This article describes the outcomes of a study involving family members of communication-impaired long-term care residents in a collaborative nursing/speech language pathology intervention designed to increase the residents' communication ability. Family members provided memorabilia and artifacts or produced audio or video tapes, for use in conjunction with a speech therapy enhancement program (STEP). Findings revealed that, despite a minimal improvement in speech ability, there was a dramatic increase in family members' satisfaction. 相似文献
992.
993.
Characterization of unique ADTN-catecholamine binding sites in the iris root-ciliary body of rabbits
A binding site for tritiated 2-amino-6, 7-dihydroxy-1, 2,3,4-tetrahydronaphthalene (ADTN) has been partially characterized in the rabbit iris root-ciliary body. Binding of ADTN is proportional to protein content and requires at least 60 minutes to reach equilibrium. Binding is saturable, with a Kd of 27 +/- 1 nM and a Bmax of 2.1 +/- .3 pmol/mg protein (mean +/- SEM). Dopamine competes for this site with a Ki of 100 nM and apomorphine with a Ki of 180 nM. This site is not blocked by L-timolol, phenoxybenzamine, or by several DA1 and DA2 antagonists. It appears to be a new type of catecholamine binding site, of a type not observed outside the anterior eye. It is possible that some of the effects of dopamine on intraocular pressure are mediated through this binding site. 相似文献
994.
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
995.
The extent to which repeated administration produces tolerance to nicotine-induced increases in dopamine transmission in the nucleus accumbens was investigated in rats. In vivo microdialysis was used to sample extracellular dopamine and metabolites after a nicotine challenge (0.35 mg/kg) in (1) naive rats, (2) acutely pretreated rats (1 prior nicotine injection), and (3) chronically pretreated rats (12-15 prior daily nicotine injections, 0.35 mg/kg per injection). Nicotine increased extracellular DA and its metabolites, and these increases were not significantly altered by either acute or chronic prior exposure to the drug. The failure to find evidence of tolerance is compatible with the hypothesis that the mesolimbic dopaminergic system is a substrate for the reinforcing properties of chronically administered nicotine. 相似文献
996.
997.
The study concerned the effects of acute and chronic clomipramine administration to male rats on exploratory activity in a novel environment (hole-board) and on immobility in the forced swimming test. Acute clomipramine administration did not alter either exploratory activity on a hole-board as measured 3 or 20 h after drug administration, or immobility in the forced swimming test as measured 20 h after drug administration. Approximately 20 h after the last injection of clomipramine, the rats chronically treated with the drug showed reduced exploratory activity on the hole-board. In contrast, chronic clomipramine treatment significantly increased the activity in the forced swimming test. The effects of the drug on exploratory and forced swimming activities persisted for 14 days after the cessation of clomipramine administration. These data indicate that chronic clomipramine administration exerted profound and long-lasting effects on central nervous system function. The long-lasting action of the drug on behaviour in the forced swimming test might explain the long-term beneficial effect of antidepressant drugs in counteracting behavioral depression. 相似文献
998.
999.
Picrotoxin but not bicuculline antagonizes 5-hydroxytryptamine-induced inhibition of cerebellar Purkinje neurons 总被引:1,自引:0,他引:1
The inhibitory effects of iontophoretically applied serotonin (5-hydroxytryptamine) on Purkinje cells were examined in the presence of the GABA antagonists picrotoxin and bicuculline in in vivo and in vitro cerebellar preparations. Continuous application of the GABA-mediated chloride ionophore antagonist, picrotoxin, at currents that induced significant antagonism of GABA-elicited inhibition of Purkinje cells decreased the inhibitory effects of serotonin significantly in the same neurons. Bicuculline, an antagonist of GABA receptors, exerted different actions on serotonin-mediated inhibition of Purkinje cells. Continuous iontophoretic applications of bicuculline antagonized the inhibitory effects of GABA on Purkinje cells significantly, but failed to induce significant attenuation of serotonin-mediated inhibition. The inhibitory effects of serotonin on Purkinje cells were examined also in the presence of nipecotic acid, an inhibitor of GABA reuptake, and a low Ca2-high Mg2+ medium, which blocks synaptic transmission. Under these circumstances, serotonin-mediated inhibitions were not influenced significantly, indicating that its inhibitory effects do not involve release or reuptake of GABA. These results indicate that there might be a linkage between the actions of serotonin and GABA. 相似文献
1000.