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41.
The purpose of this study was to provide data on the social functioning (i.e., the degree of peer acceptance, self-concept, loneliness, and social alienation) of students in second, third, and fourth grade who participated in an inclusive classroom for an entire year. The social functioning of students identified as learning disabled (LD; n = 16), low achieving (LA; n = 27), and average/high achieving (AHA; n = 21) was assessed at the beginning and end of the school year. The students with LD were less well liked and more frequently rejected than AHA students. Although students' overall self-worth did not differ by achievement group, the students with LD demonstrated significantly lower academic self-concept scores. The students with LD did not differ on ratings of loneliness, and they demonstrated increases in the number of within-class reciprocal friendships from fall to spring. Discussion focuses on the effects of inclusion on the social functioning of students with LD. 相似文献
42.
H Mahalingam J Vaughn J Novotny JR Gruber RM Niles 《Canadian Metallurgical Quarterly》1996,168(3):549-558
Serotonergic neuronal networks are important for food intake and body weight regulation. Dexfenfluramine (dF), a serotonin releaser and reuptake inhibitor, was used to investigate changes in food intake, body weight development, energy expenditure, respiratory quotient, and substrate oxidation rates for 12 days. Rats, which had been made obese by early postnatal overfeeding, received an energy-controlled mash diet and water ad lib and were intraperitoneally injected daily with either saline, 5 or 10 mg dF/kg. Compared to controls, food intake, body weight development, and energy expenditure were decreased in a dose-dependent manner, especially during the first 6 days. Lipid oxidation was increased while oxidation of carbohydrates was decreased. Pair-feeding experiments over 2 days revealed that this was not solely a result of diminished food intake but also an additional metabolic effect of dF, different from its anorectic effect. At the end of these experiments, plasma glucose and liver glycogen were unchanged after dF, but plasma free fatty acids were significantly decreased. Insulin-sensitivity was probably improved, indicated by decreased insulin levels and increases in muscle glycogen contents and activities of muscle pyruvate kinase. Liver-glutamine and contents of valine, leucine, and isoleucine in the muscle were significantly decreased after dF-treatment, the latter indicating a diminished proteolysis. The plasma tryptophan/large neutral amino acids ratio of the dF-rats was unchanged but that of the paired-fed rats was changed, despite similar changes in food intake. It is concluded that both increased oxidation of endogenous fat and reduced food intake could mediate the body weight reducing effect of dF. 相似文献
43.
LN Tremblay T Yamashiro KN DeCampos BV Mestrinho AS Slutsky TR Todd SH Keshavjee 《Canadian Metallurgical Quarterly》1996,15(3):260-268
BACKGROUND: A shortage of suitable brain-dead donors continues to severely limit lung transplantation. Use of donors with nonbeating hearts has been suggested as a solution. Lungs are unique, in that aerobic metabolism can continue in the absence of blood circulation because oxygen is present in airways and alveoli. Animal studies have shown reasonable cadaveric graft function up to several hours after sudden death by drug administration. However, hemodynamic instability before death may worsen lung function through activation and pulmonary sequestration of neutrophils and release of inflammatory mediators. Because many potential cadaveric donors experience hypotension before death, this study was undertaken to assess the effect of hypotensive shock on cadaveric lung viability. METHODS: A rat isolated lung reperfusion model was used to assess pulmonary function over 3 hours of reperfusion or until gross pulmonary edema developed. Twenty-five rats were randomly allocated to the following study groups, which were based on status before lung harvest: (1) control: no interventions; (2) hypotensive: 1 hour of hypotension by exsanguination to a mean blood pressure of 30 to 40 mm Hg; (3) cadaver: death by cervical dislocation followed by 3 hours of in situ lung ischemia; (4) hypotensive + 3 hours cadaver: 1 hour of hemorrhagic shock, followed by death and 3 hours of in situ ischemia; (5) hypotensive + 2 hours cadaver: similar to group 4, except the in situ ischemia was abbreviated to 2 hours. RESULTS: No significant differences were found among group 1, 2, or 3 lungs with regard to wet to dry weight ratios, gas exchange, and pulmonary arterial or airway pressures. However, all group 4 lungs became grossly hemorrhagic and developed severe pulmonary edema within 10 minutes of reperfusion. Group 5 lungs fared only marginally better, with two of five lungs tolerating 3 hours of reperfusion. CONCLUSIONS: A period of hypotension before death severely impairs cadaveric lung viability. 相似文献
44.
Vaughn Brian E.; Kopp Claire B.; Krakow Joanne B.; Johnson Kim; Schwartz Steven S. 《Canadian Metallurgical Quarterly》1986,22(6):752
Conducted 2 studies to examine the behavior of young children in tasks demanding self-control. In Study 1, 27 2-yr-olds were observed in 1 task. Behavior during the task was described using a 10-category coding system, and proportion scores derived from the 10-category coding system were correlated with total time in the task. Results show that 5 of the 10 correlations were significant. Behaviors bringing the goals into attention were negatively correlated with total delay time, whereas behaviors taking the goal out of attention tended to be positively associated with delay. In Study 2, 82 children (aged 24–36 mo) were observed in 3 delay tasks. The behavioral strategy studied was directing attention away from the goal object during delay periods. Significant effects were found for age and task type. When the sample was divided into shorter vs longer waiters, it was found that the longer waiters looked away from the goal for a larger proportion of the time. It is suggested that young children use implicit strategies for controlling their behavior in the face of a social demand. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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47.
BV Venkataraman S Dutt J Czekajewski L Nennerfelt C Williams 《Canadian Metallurgical Quarterly》1995,39(3):283-286
A simple method has been developed for continuous monitoring of metabolic activity of an isolated, perfused rat heart by O2/CO2 respirometer. Since respirometer provides vital data on oxygen consumption and carbon dioxide production of a preserved organ on a continuous basis over a long period of time, it will be possible to use this method to monitor viability of not only isolated heart but also any given donor organ under preservation. 相似文献
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49.
López Steven Regeser; Nelson Hipke Kathleen; Polo Antonio J.; Jenkins Janis H.; Karno Marvin; Vaughn Christine; Snyder Karen S. 《Canadian Metallurgical Quarterly》2004,113(3):428
The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
The author examines the ways in which a psychoanalytic perspective may illuminate the underlying developmental dynamics of children of lesbian parents. Families headed by gay and lesbian parents demand reconsideration of a theory of oedipal development based on heterosexual parents. If triangulation, the move from dyadic to triadic object relationships, depends on 2 primary processes--the child's acceptance of the immutability of generations and the child's recognition that children are excluded from the world of adult sexuality--parental gender or sexual orientation assumes less importance. The emergence of conscience from multifaceted processes of identification is consistent with this view of triangulation as a developmental phase. Children of gay and lesbian parents must be offered theories of healthy development that include them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献