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Pallarito K Greene J Lutz S Kenkel PJ Morrissey J Burns J de Lafuente D Scott L Burda D Japsen B 《Modern healthcare》1994,24(1):31-8, 40-4, 46-8
With healthcare reform on the horizon, healthcare companies and providers are positioning themselves for a new environment in which cost-effective medical treatment is the Holy Grail. Not only will providers be required to measure the efficiency of their treatments, but all parties in the medical-care delivery system will need to share financial risk. In the following pages Modern Healthcare staff members look at how specific industry segments are preparing to face the changes expected during the rest of the 1990s. Industry experts also express their views. 相似文献
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G. Morrissey M. -Y. Ho Mary A. Wogar C. M. Bradshaw E. Szabadi 《Psychopharmacology》1994,114(3):463-468
Twelve rats received injections of 5,7-dihydroxytryptamine into the dorsal and median raphe nuclei; 12 rats received sham lesions. The rats were then trained for 60 sessions under a discrete-trials fixed-interval schedule (peak procedure). In half the trials, a reinforcer became available 40 s after trial onset, and the trial was terminated upon reinforcer delivery; the remaining trials were 120 s in duration, and reinforcement did not occur in these trials. Performance during the 120-s trials was characterized by increasing response rate during the first 40 s of the trial, declining response rate between 40 s and 80 s, and a secondary increase in response rate during the final 40 s of the trial. The lesioned group showed a broader spread of the response rate function than the control group (time between attainment of 70% of the peak response rate and subsequent decline of response rate below this level); however, the peak response rate and the time from trial onset until attainment of the peak response rate did not differ significantly between the groups; the spread/peak-time ratio was significantly greater in the lesioned group than in the control group. The levels of 5-hydroxytryptamine (5HT) and 5-hydroxyindoleacetic acid in the parietal cortex, hippocampus, amygdala, nucleus accumbens and hypothalamus were markedly reduced in the lesioned group, but the levels of noradrenaline and dopamine were not significantly affected by the lesion. The results confirm the involvement of 5HTergic function in timing behaviour. 相似文献
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