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941.
The authors studied the influence of variable stimulation patterns on parameters of afterhyperpolarization (AHP) in rat spinal motoneurons using intracellular recording of antidromic action potentials. The action potentials analyzed were evoked by either (a) a single stimulus or pair of stimuli with gradually increasing interpulse intervals (IPI) of 5-20 ms or (b) an increasing number of stimulus pulses, from 1 to 4, at a constant IPI. It was demonstrated that modulations of AHP parameters after 2 pulses depended on the IPI, whereas the most significant changes in these parameters were found after the application of 2 or 3 stimuli in a series. The authors propose that changes in the AHP parameters have functional significance for motoneuronal firing pattern and therefore for motor unit force development during tetanic contractions.  相似文献   
942.
The 1st purpose of this study was to examine multiple electromyography (EMG) during voluntary hand movements. A secondary purpose was to investigate possible effects of pressure on intracortical inhibition (ICI) and intracortical facilitation (ICF) functions of the motor cortex, using paired-pulse transcranial magnetic stimulation. Twelve participants traced a 15-cm diameter target circle using a small laser pointer attached to the right index finger. After 5 acquisition trials, they performed 3 nonpressure trials followed by 3 pressure trials. The results showed that pressure had effects not only on agonist EMG activity but also on multiple muscles, such as synergist. In addition, a decrease in ICI and an increase in ICF were both observed under pressure for muscles other than the agonist.  相似文献   
943.
Cultural issues impact on health care, including individuals’ health care behaviours and beliefs. Hasidic Jews, with their strict religious observance, emphasis on kabbalah, cultural insularity and spiritual leader, their Rebbe, comprise a distinct cultural group. The reviewed studies reveal that Hasidic Jews may seek spiritual healing and incorporate religion in their explanatory models of illness; illness attracts stigma; psychiatric patients’ symptomatology may have religious content; social and cultural factors may challenge health care delivery. The extant research has implications for clinical practice. However, many studies exhibited methodological shortcomings with authors providing incomplete analyses of the extent to which findings are authentically Hasidic. High-quality research is required to better inform the provision of culturally competent care to Hasidic patients.  相似文献   
944.
This study's primary goal was to evaluate the use of performance feedback procedures delivered to a classroom team to increase daily data collection. Performance feedback (PFB) was delivered to four classroom teams responsible for the daily collection of data representing student performance during prescribed instructional activities. Using a multiple-baseline design, the effects of the team performance-feedback were evaluated for the target student, and for generalization to data collection for all classroom students. A secondary question evaluated if student on-task behavior correlated with increased data collection. Finally, social validity was investigated to evaluate team satisfaction with the PFB intervention. The results demonstrate improved data collection across all four classroom teams for the target student in each classroom and generalization within classrooms to all remaining students. Slight increases in student on-task behavior were observed in three of the four classrooms, and teacher satisfaction ratings were high.  相似文献   
945.
Daily activity levels were investigated as related to sleep quality in young adult college students aged 18 to 30 years. 85 participants (20 men, 65 women) completed the Young Adult Daily Activity Scale (YADAS). This 37-item checklist has 34 items based on focus group discussion points of college students' typical daily activities and three blank items for students to include their daily activities if not in the listing. The tabulation of type and amount of waking daily activities represents a unique measurement of factors that may affect sleep quality. The participants also rated their typical sleep quality using a standard 5-point scale (low indicating poor sleep). Correlations of sleep ratings and activities were not significant.  相似文献   
946.
947.
To contrast mechanisms of lexical access in production versus comprehension we compared the effects of word frequency (high, low), context (none, low constraint, high constraint), and level of English proficiency (monolingual, Spanish-English bilingual, Dutch-English bilingual) on picture naming, lexical decision, and eye fixation times. Semantic constraint effects were larger in production than in reading. Frequency effects were larger in production than in reading without constraining context but larger in reading than in production with constraining context. Bilingual disadvantages were modulated by frequency in production but not in eye fixation times, were not smaller in low-constraint contexts, and were reduced by high-constraint contexts only in production and only at the lowest level of English proficiency. These results challenge existing accounts of bilingual disadvantages and reveal fundamentally different processes during lexical access across modalities, entailing a primarily semantically driven search in production but a frequency-driven search in comprehension. The apparently more interactive process in production than comprehension could simply reflect a greater number of frequency-sensitive processing stages in production.  相似文献   
948.
Children typically follow a well-defined series of stages as they learn to draw, but the rate at which they progress through these stages varies from child to child. Some experts have argued that these individual differences in drawing development reflect individual differences in intelligence. Here we assessed the validity of a drawing test that is commonly used to assess children’s intellectual abilities. In a single study, 125 5- and 6-year-olds completed the Draw-A-Person: A Quantitative Scoring System (DAP:QSS) and the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) or the Wechsler Abbreviated Scale of Intelligence (WASI). Although there was a statistically significant correlation between scores on the DAP:QSS and scores on the Wechsler tests, when the scores of individual children were examined, the DAP:QSS yielded a high number of false positives and false negatives for low intellectual functioning. We conclude that the DAP:QSS is not a valid measure of intellectual ability and should not be used as a screening tool.  相似文献   
949.
In the presence of several objectives, goal conflict may be avoided via multifinal means, which advance all of the active goals at once. Because such means observe multiple constraints, they are fewer in number than the unconstrained means to a single goal. Five experimental studies investigated the process of choosing or generating such means for multiple goals. We found that the simultaneous activation of multiple goals restricted the set of acceptable means to ones that benefitted (or at least, did not harm) the entire set of active goals. Two moderators of this phenomenon were identified: (a) the feasibility of identifying multifinal means, which was dependent on the relations between the different active goals, and (b) the enhanced importance of the focal goal, which resulted in the inhibition of its alternatives and the consequent relaxation of multifinality constraints.  相似文献   
950.
This study reports preliminary psychometric findings for a seven-item religiosity scale in a community-based sample of Vietnamese Americans ages 18 to 83 years (N = 119; 58% women, 42% men). A bilingual survey was distributed to Vietnamese who were evacuated during Hurricane Katrina and had returned after the disaster. Internal consistency, factorial structure validity, and criterion validity were evaluated on the scale items. The bilingual scale had good internal consistency. While exploratory and confirmatory factor analysis results provided support for a two-factor structure which captured Religious Involvement and Religious Coping, a one-factor model had slightly better fit. Individuals who scored high on the religiosity scale reported a significantly lower score on their stressful experiences during the hurricane, providing evidence of criterion validity.  相似文献   
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