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101.
102.
Perkins M 《Clinical linguistics & phonetics》1994,8(4):321-336
A common feature of a wide range of language disorders is the tendency to repeat a particular linguistic form-or set of forms-with abnormal frequency. A brief overview is given of the different ways in which disordered language can be repetitive, and the nature of stereotyped and repetitive language is discussed in terms of the reciprocal relationship between frequency of occurrence and productivity. It is argued that measures such as lexical type-token ratio provide only a partial picture of repetitive language, and that linguistic units larger than the word also need to be taken into consideration. An analytical framework incorporating such units is proposed, which is able to characterize and quantify the extent to which a sample of language is repetitive independently of its aetiology. An illustrative analysis is given of a language sample from a brain-damaged adult, and the repetitiveness profiles of four different patients are compared. 相似文献
103.
Perkins D 《Journal of AHIMA / American Health Information Management Association》1994,65(11):30, 32-30, 33
104.
Associations of parity with body fat and its distribution are poorly understood; therefore, we examined the relationships between parity and obesity in young adult women. Body mass index (BMI), skin-folds, and waist-hip ratio were compared in 1452 African-American and 1268 Caucasian nonpregnant women aged 18 to 30, adjusting for age (where no age-parity interactions were present), education, physical activity (assessed by questionnaire) and fitness (assessed by graded exercise test), dietary fat intake, alcohol and smoking. Adjusted mean BMI was significantly higher in African-American women aged 25-30 years with three or more children (28.5 kg/m2) than in those with two (27.0 kg/m2), one (26.2 kg/m2), or no children (26.3 kg/m2). Similar trends were found in Caucasians (BMI = 23.3, 23.4, 23.7, 25.0 kg/m2 for parity = 0, 1, 2, > or = 3, respectively), but the mean BMI was significantly higher in African Americans in each parity group. The association between BMI and parity was not present among women 18-24 years of age. Skinfolds were directly associated with parity in African Americans only. Waist-hip ratios were generally lower among nulliparous than parous women in both ethnic groups; race differences were present only among nulliparas. In conclusion, parity was associated with BMI in women aged 25 to 30 years but did not explain ethnicity-related differences in body mass. 相似文献
105.
EEG power spectral analysis was studied from 14 (alumina-gel) chronically epileptic, undrugged monkeys during an EEG operant conditioning experiment. The composite profile of the average epileptic monkey shows the majority of power to be below 10 Hz. Because of the large variance in the data, no significant changes in the EEG power spectra could be detected as a function of conditioning. The possible reasons for this large variance are discussed. Hypothesis from previous human "biofeedback" studies would allow the prediction that those frequencies corresponding to the mu and sensory-motor-rhythm should negatively covary with seizure frequency. Data from this study did not support such assertions. The method of using spectral analysis for quantifying changes in the EEG which covary with operant conditioning is evaluated. 相似文献
106.
The vasa vasorum and angioplasty 总被引:2,自引:0,他引:2
Cragg AH; Einzig S; Rysavy JA; Castaneda-Zuniga WR; Borgwardt B; Amplatz K 《Radiology》1983,148(1):75-80
Interruption of flow in the vasa vasorum may lead to medial necrosis and aneurysm formation. The purpose of this study was to determine whether angioplasty produces significant alterations in the morphology or blood flow of the vasa vasorum of the dilated artery. The morphology of the canine vasa vasorum was studied before and after angioplasty; in a separate experiment vessel wall blood flow (VWBF) in canine carotid arteries was measured after angioplasty to determine whether physiologic regulation of the blood flow was disrupted by arterial dilation. No morphologic changes could be demonstrated in the vasa vasorum of the dilated artery; however, VWBF was increased by 1194 +/- 215% (mean +/- standard error, p less than 0.01) between 90 and 120 minutes after angioplasty. VWBF in the adjacent nondilated arterial segment was also increased (720 +/- 177% between 10-30 minutes, p less than 0.01) but returned toward normal after 60 minutes. Adenosine caused a "paradoxical" decrease in VWBF (p less than 0.05) of the dilated arterial segment while causing increased VWBF (p less than 0.05) in the thoracic aorta. Angioplasty appears to produce persistent hyperemia in the dilated arterial wall. A paradoxical response to adenosine suggests that vasa vasorum in the dilated arterial segment are maximally vasodilated. This may be due to mechanical disruption of vasomotor tone or to release of vasoactive substances. 相似文献
107.
108.
Kenneth A. Perkins Leonard H. Epstein Richard L. Stiller Madelyn H. Fernstrom Joan E. Sexton Rolf G. Jacob Rena Solberg 《Psychopharmacology》1991,103(1):103-109
The inverse relationship between smoking and body weight may be due in part to nicotine's effects on reducing hunger and eating. Male smokers and nonsmokers (n=10 each), abstinent overnight from smoking and food, participated in four sessions, involving consumption of a liquid caloric load or water followed by nicotine (15 µg/kg) or placebo via nasal spray every 20 min for 2 h. Hunger and satiety (fullness) ratings were obtained prior to each dose presentation. At the end of the two sessions involving the caloric load (simulating breakfast), subjects were also presented with typical lunch/snack food items varying in sweet taste and fat content for ad lib consumption. Results indicated that, for both smokers and nonsmokers, the hunger-reducing effects of nicotine occurred only following caloric load consumption, and there was no effect of nicotine on hunger after water consumption. Smokers unexpectedly reported greater satiation than nonsmokers following the caloric load regardless of nicotine or placebo condition. Nicotine also resulted in less caloric intake during the meal, and the decrease was not specific to consumption of sweet, high-fat foods. These results indicate that nicotine reduces appetite, possibly helping to explain the influence of smoking on body weight. 相似文献
109.
110.
H W Perkins 《Journal of studies on alcohol》1992,53(5):458-462
Although college men have typically reported significantly more alcohol problems than women, debate about a possible convergence of gender differences has emerged in recent years. Time trend data on gender differences based on consistent measures of alcohol-related problems are scant, however. Another limitation of previous research has been the predominant focus on alcohol problems most common among men. This article provides data on gender differences and trends in several types of negative consequences of student drinking in a collegiate population from four surveys conducted between 1979 and 1989. The data do not support an overall "convergence hypothesis" as men remained much more problematic in several types of consequences-specifically abuse problems that are public, involve legal repercussions, or that endanger others. Consequences that are more personal or less prone to provoke public response reveal little or no gender differences, however, in the most recent collegiate cohorts. Thus, more gender research is needed on types of alcohol problems in campus context. 相似文献