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991.
This research was designed to test the extent to which health education and health services administration students' perceptions of their roles as professionals matched the expectations of professional faculty. These perceptions were found to match in general. However, doubt was cast on the extent to which internships or practicums contributed to this result, since there was no change in student responses between the beginning of the junior year and end of the senior year, a period which includes fieldwork and most of the professional coursework presumed to influence professional development. Additional research is required to test this result with other student populations in other health professions and identify the point at which professional role and task definitions are amenable to change. 相似文献
992.
We investigated the effects of imaging and display conditions on the detectability of low-contrast objects in digital subtraction angiographic (DSA) images. The test images were produced by superimposition of low-contrast objects on a uniform noisy background obtained with a DSA system. We employed 18-alternative forced-choice (18-AFC) experiments and predictions based on statistical decision theory to study the dependence of the threshold contrasts of the test objects on the object size, incident x-ray exposure, display window width, and display medium. The results indicated that the threshold contrast decreased with increasing object size, and that the detectability of an object of a given size increased with increasing incident x-ray exposure and decreasing width of the display window. We found that the signal-to-noise ratio (SNR) obtained from the perceived statistical decision theory model, which includes the observer's internal noise, can accurately predict the detectability of low-contrast objects in DSA images. The threshold SNR corresponding to 50% correct detection in the 18-AFC experiments had a constant value of 3.8, in agreement with results reported previously for screen-film systems. The theoretical model will be useful for prediction of the performance of a DSA system based on its physical characteristics, and for evaluation of the tradeoff between patient exposure and diagnostic accuracy for a given DSA unit. 相似文献
993.
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996.
Norfloxacin, a new quinolinecarboxylic acid derivative, was administered to 30 male patients with gonococcal urethritis at a daily dose of 600 mg for 7-21 days. The clinical response was evaluated after administration of 7 days as excellent; Negative culture of N. gonorrhoeae. WBC less than 3/hpf in first voided urine sediment, good; Negative culture, WBC greater than or equal to 3/hpf, and poor; Positive culture. The result was excellent in 14 cases and good in 16 cases. No subjective side effects were observed. The minimum inhibitory concentration (MIC) distribution against the clinically isolated 30 strains of N. gonorrhoeae ranged from 0.0096 micrograms/ml to 0.34 micrograms/ml. Seven of thirty strains were resistant to ABPC. The MIC of these 7 strains ranged from 0.018 micrograms/ml to 0.18 micrograms/ml. Seven cases with ABPC resistant strains had a similar clinical response to other cases. Twelve patients (40%) developed post gonococcal urethritis for 7-14 days after treatment. Clinical observation of this series suggests that a 7 day therapy of Norfloxacin for the patients with gonococcal urethritis is sufficiently effective and that treatment should be changed to other antibacterial agents in the case of post gonococcal urethritis, since continuous administration for more than 7 days of Norfloxacin is not so effective. 相似文献
997.
Principles of battlefield psychiatry 总被引:2,自引:0,他引:2
D K Kentsmith 《Military medicine》1986,151(2):89-96
998.
I Immonen K Friberg C Gr?nhagen-Riska E von Willebrand F Fyhrquist 《Acta ophthalmologica》1986,64(5):519-521
Angiotensin-converting enzyme (ACE) was studied immunohistochemically in conjunctival biopsies from 6 patients with systemic sarcoidosis, 4 patients with posterior non-sarcoid uveitis and in specimens from 4 patients with chalazion of the eyelid. Specimens with sarcoid granulomas showed intense ACE-positive immunoreactivity in epitheloid cells of the granuloma, whereas chalazion granulomas did not contain ACE-immunoreactivity. There was no difference in staining patterns between specimens without granulomas. Thus immunohistochemical staining for ACE may be of help in differentiating conjunctival granulomatous tissue of a chalazion from sarcoid granuloma. 相似文献
999.
Cocaine-treated rats acquired a preference for cocaine-associated contextual stimuli (CS) relative to saline-injected control rats. However, when animals were given repeated tests for conditioned place preference intermittent between conditioning trials, they displayed an attenuation in strength of conditioning. This attenuation was not due to pharmacologic tolerance (Experiment 1), but rather reflected a disruption in learning due to exposure to the CS alone (Experiment 2). Like other examples of classical conditioning, the strength of the conditioned response (CR) as assessed by the conditioned place preference model may be influenced by partial reinforcement. 相似文献
1000.
This study investigated social interactions between infants and mothers, comparing dyads with physically disabled infants and dyads with nondisabled infants. The groups were matched on mental and motor development, sex, socioeconomic status, birth order, and maternal education. Each infant-mother dyad was videotaped at home during a 10-minute period of free play, and blind observers subsequently transcribed infants' and mothers' behaviors. In general, the groups were remarkably similar in their interaction patterns. However, a few differences emerged: Mothers of infants with physical disabilities were significantly more commanding than were comparison mothers. Nondisabled infants tended to engage in more eye contact than did infants with physical disabilities. And whereas mothers of nondisabled infants responded to interactive play with interactive play, mothers of infants with physical handicaps tended to respond with commands and verbalizations. These results suggest reciprocal influences between infants and mothers in both groups and highlight emerging maternal behavior patterns that may interfere with the development of communication and independence in handicapped young children. 相似文献