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981.
Traditional Dental Aptitude Test and academic grade point average have been shown to be poor predictors of clinical performance by dental students. To refine predictors of psychomotor skills, a wire-bending test was given to 105 freshmen at the beginning of their dental education. Grades from seven restorative preclinical courses in their freshman and sophomore years were compared to scores on wire bending and the three traditional predictors: GPA, academic aptitude, and perceptual aptitude scores. Wire-bending scores correlated significantly with six out of seven preclinical restorative courses. The predictive power for preclinical performance was doubled when wire bending was added to traditional predictors in stepwise multiple regression analysis. Wire-bending scores identified students of low performance. These preliminary results suggest that the wire-bending test shows some potential as a screening test for identifying students who may hae psychomotor difficulties, early in their dental education.  相似文献   
982.
Reaction time (RT) for two three-segment target-striking responses involving changes in direction of movement was studied as a function of differences in their additive index . . . index of difficulty (A-ID). In one condition the A-ID was 9.96 and in the other, 6.76. For 16 right-handed university students, mean RT was significantly faster for the condition in which the index was 6.76. Movement times were consistent with Fitts' Law. The data support Sidaway, Christina, and Shea's 1988 prediction that for target-striking movements with changes of direction, RT is a function of the cumulative series of movement constraints.  相似文献   
983.
This study is a systematic replication of the effects of insulin doses on operant behavior reinforced (in an earlier study) by fixed-ratio schedules of microwave (MW) reinforcement. In this study, insulin and dextrose doses were administered (ip) prior to fixed-interval 2-min. schedules of MW reinforcement in rats tested in a cold environment. Six Sprague-Dawley rats were conditioned to regulate their thermal environment with 5-sec. exposures of MW radiation (SAR = 0.34 Watts/kg/(mW/cm2) under the FI-2' schedules. Humulin-regular insulin and 50% solutions of dextrose were administered (ip) alternately with saline control sessions for 8-hr. durations. A within-subjects, repeated-measures 4 x 8 x 3 factorial analysis of variance design showed that insulin doses suppressed operant responding for heat, which confirmed the results of the earlier study under a different schedule. In addition, high doses of dextrose had similar suppressing effects on operant responding for heat. The data are interpreted in terms of the discriminative properties of increased thermogenesis produced by the insulin and dextrose doses. The suppressing effects were more pronounced for the first two hours, yet they persisted for approximately six hours of the 8-hr. sessions.  相似文献   
984.
Although research has established the criterion-related validity of assessment centers for selection purposes, the construct validity of dimension ratings has not been demonstrated. A quasi-experimental design was used to investigate the influence of retranslated behavior checklists on the construct validity of dimension ratings for two assessment center exercises. Assessor use of behavior checklists increased the average convergent (i.e., same dimension across exercise) validity from .24 to .43 while decreasing the average discriminant (i.e., different dimension within exercise) validity (.47 to .41). Behavior checklist sums were moderately correlated with corresponding dimension ratings and demonstrated a comparable level of construct validity. It is suggested that using behavior checklists may improve dimension construct validity by reducing the cognitive demands placed on raters.  相似文献   
985.
986.
A group of 107 children with vascular diseases of the nervous system aged 3-14 years have been studied. In 100 children of the study group acute disturbances of the brain blood circulation have been found, out of which 37 children were with transitory ischemic attacks; 29 were found to be with brain ischaemia; 22-with haemorrhages (7 cases with subarchnoidal, 9 cases with intracerebral and 6 cases with subarachnoidal-parenchimatose); 5 children had wenous thromboses; 7 children were with spinal strokes. In other 7 children we found the presence of Sturge-Weber syndrome. Congenital vascular malformations have been found in 32 children (30%), out of which 16 children (15%) with loops and stenosis of the extracranial segments of the internal carotid artery, and another 16 children (15%) with AV-malformations. Congenital and acquired heart diseases are found to be primary cause for the strokes in 12 children (11%). Considerable is the rate of the epileptic seizures in the acute stage of the strokes as well as of the residual epileptic syndromes.  相似文献   
987.
In a paranoid-hallucinatoric patient with chronic course and acute exacerbation a EEG mapping study during neuroleptic treatment was carried out. The typical changes of the alpha power spectra in schizophrenic psychoses as well the normalization after neuroleptic treatment could be found in the alpha map. The changes were in correlation to the clinical state.  相似文献   
988.
The heterogenous psychoses in epilepsies, caused by well known conditions, are not rare but associated with regularly a few of seizure-types not with the nature and development of attacks. Polar transitional ranks and converging courses of schizophrenic (accentuated) syndromes in epilepsies and idiopathic schizophrenias are rather frequent. Also (sub-)acute schizophrenic psychoses are corresponding to the complete palette of first and second rank symptoms (K. Schneider) of idiopathic schizophrenias. After manifestations of epilepsy these syndromes can appear at any time. It is given a profile of risks. Progressive avoidance of a. phenylaceturea, b. mixtures of antiepileptics did not put an end to psychotic syndromes: Long-term therapies with 1. Polytherapy, 2. Primidone and Phenytoin (dosedependant) as well as 3. Ethosuximide (-monotherapy) cause a disorder of feed back mechanisms, especially a disturbed regulation of vigilance and sleeping-waking-cycle and their psychological correlates. Carbamazepine and Sodium Valproate are, plasma-level-controlled of preventive antipsychotic effect. Selected neuroleptics of rather slight epileptogenic potency are of going down importance. Benzodiazepines are required mostly in prepsychotic syndromes, Lithium compounds in selected cases. There is no more alternative seizures or psychosis.  相似文献   
989.
While among 194 high school students 79 first-borns showed less fear of negative consequences of academic success than 78 last-borns and 37 middle-borns, no differences were observed on fear of increased positive attention or of increased responsibility.  相似文献   
990.
Information search following damage to the frontal lobes   总被引:2,自引:0,他引:2  
Five adult patients with focal brain damage in different areas of the frontal lobes and five matched controls were administered a 20 Questions test. Other tests of planning, problem-solving, and decision-making were also administered to frontal lobe patients. The results indicate that damage to the frontal lobe impairs the ability to impose and utilize hierarchical organization in mental representation.  相似文献   
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