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1.
The present study was designed to investigate the chemical properties of the aggression-promoting cues present in bladder urine of male mice. The results of the first experiment confirmed earlier work by demonstrating the presence of an aggression-promoting chemosignal in bladder urine. In Experiment 2, behavioral assays were separately performed on the organic and aqueous layers of bladder urine obtained by repeated dichloromethane extractions. Only the combined organic layers of the initial three extractions demonstrated behavioral activity. A fourth extraction showed no behavioral activity for both organic and aqueous layers. However, the findings of Experiment 3 showed that incubation of the aqueous layer from the third CH2Cl2 extraction in β-glucuronidase can free additional aggression-promoting cues into a subsequent CH2Cl2 extraction. It is concluded that two forms of the aggression-promoting chemosignal are present in bladder urine. One is lipophilic and behaviorally active, whereas the other is conjugated, possessing latent chemosignal properties.  相似文献   
2.
PURPOSE: Medical College Admission Test (MCAT) examinees with disabilities who receive accommodations receive flagged scores indicating nonstandard administration. This report compares MCAT examinees who received accommodations and their performances with standard examinees. METHOD: Aggregate history records of all 1994-2000 MCAT examinees were identified as flagged (2,401) or standard (297,880), then further sorted by race/ethnicity (broadly identified as underrepresented minority and non-URM, at the time of testing) and gender. Those with flagged scores were also classified by disability (LD = learning disability, ADHD = attention deficit hyperactivity disorder, LD/ADHD = learning disability and attention deficit hyperactivity disorder, and Other = other disability) and type of accommodation. Mean MCAT scores were calculated for all groups. A group of 866 examinees took the MCAT first as a standard administration and subsequently with accommodations. In a separate analysis, their two sets of scores were compared. RESULTS: Less than 1% of examinees (2,401) had accommodations; of these, 55% were LD, 17% ADHD, 5% LD/ADHD, and 23% Other. Extended time was the most frequently provided accommodation. Mean flagged scores slightly exceeded mean standard scores on all MCAT sections. Examinees who retook the MCAT with accommodations after a standard administration increased their scores by six points, quadrupling the average gain Standard-Standard retest cohort from another study. CONCLUSION: The small but statistically significant different higher flagged scores may reflect either appropriate compensation or overly generous accommodations. Extended time had a positive impact on the scores of those who retested with this accommodation. The validity the flagged MCAT in predicting success in medical school is not known, and further investigation is underway.  相似文献   
3.
Cold application is commonly used before strenuous exercise due to its hypalgesic effects. Some have questioned this procedure because of reports that cold may reduce isokinetic torque. However, there have been no investigations of actual physical performance following cold application. The purpose of this study was to determine if a 20-minute ice immersion treatment to the foot and ankle affected the performance of three agility tests: the carioca maneuver, the cocontraction test, and the shuttle run. Twenty-four male athletic subjects were tested during two different treatment sessions following an orientation session. Subjects were tested following a 20-minute 1°C ice immersion treatment to the dominant foot and ankle and 20 minutes of rest. Following each treatment, subjects performed three trials of each agility test, with 30 seconds rest between each trial, and 1 minute between each different agility test. The order in which each subject performed the agility tests was determined by a balanced Latin square. A MANOVA with repeated measures was used to determine if there was an overall significant difference in the agility times recorded between the cold and control treatments and if the order of the treatment sessions affected the scores. Although the mean agility time scores were slightly slower following the cold treatment, cooling the foot and ankle caused no difference in agility times. Also, there was no difference resulting from the treatment orders. We felt that the slightly slower scores may have been a result of tissue stiffness and/or subject's apprehension immediately following the cold treatment. Cold application to the foot and ankle can be used before strenuous exercise without altering agility.  相似文献   
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This study examines two sources of informal support??perceived family and friend support??and the psychological well-being??self-esteem, depression and loneliness??of 150 Chinese and 145 American elders. There were no significant differences between the elderly American and Chinese persons?? mean scores on family and friend support. The multiple linear regression analyses with interaction terms (country x family support and country x friend support), however, indicated that the relationship between family support and depression and family support and loneliness was stronger for the Chinese elderly than the US elderly. Conversely, the relationship between friend support and depression and friend support and loneliness is stronger for US elderly than Chinese elderly. The implications of these findings for social work practice in both countries is discussed.  相似文献   
6.
AIDS and Behavior - A randomized controlled trial evaluated the preliminary efficacy of a dyadically-delivered motivational interviewing (MI) intervention to reduce drug use and sexual risk in a...  相似文献   
7.
Previous research has explored the efficacy and effectiveness of autism spectrum disorder (ASD) parent training interventions. Recent trials of such programs have not replicated earlier compelling outcomes, yet the reasons for the failure of such programs to produce desired effects are unclear. The purpose of the current article is to discuss the role of intervention fidelity in elucidating the relationships between a parent training program, the implementation and sustainability of an intervention, and important child outcomes. The article will discuss the importance of assessing intervention fidelity for the identification and successful use of effective treatment strategies and will propose an integrative conceptual framework for approaching the study and evaluation of intervention fidelity with respect to ASD parent training programs.  相似文献   
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Project ImPACT is a parent-mediated social communication intervention for young children with ASD that was developed in community settings to encourage dissemination. A single-subject, multiple-baseline design was conducted across 8 preschoolers with ASD and their mothers to examine the efficacy of the model for improving parent intervention fidelity and child spontaneous language. Multilevel modeling was used to examine the relationship between parent fidelity and child language within session. All parents increased their use of the intervention techniques. Improvements in spontaneous use of language targets were observed for 6 of the 8 children. There was a significant association between parents’ use of the intervention strategies and their child’s spontaneous language use.  相似文献   
10.
Accumulation of oxidative damage to mitochondria, protein, and nucleic acid in the brain may lead to neuronal and cognitive dysfunction. The effects on cognitive function, brain mitochondrial structure, and biomarkers of oxidative damage were studied after feeding old rats two mitochondrial metabolites, acetyl-l-carnitine (ALCAR) [0.5% or 0.2% (wt/vol) in drinking water], and/or R-alpha-lipoic acid (LA) [0.2% or 0.1% (wt/wt) in diet]. Spatial memory was assessed by using the Morris water maze; temporal memory was tested by using the peak procedure (a time-discrimination procedure). Dietary supplementation with ALCAR and/or LA improved memory, the combination being the most effective for two different tests of spatial memory (P < 0.05; P < 0.01) and for temporal memory (P < 0.05). Immunohistochemical analysis showed that oxidative damage to nucleic acids (8-hydroxyguanosine and 8-hydroxy-2'-deoxyguanosine) increased with age in the hippocampus, a region important for memory. Oxidative damage to nucleic acids occurred predominantly in RNA. Dietary administration of ALCAR and/or LA significantly reduced the extent of oxidized RNA, the combination being the most effective. Electron microscopic studies in the hippocampus showed that ALCAR and/or LA reversed age-associated mitochondrial structural decay. These results suggest that feeding ALCAR and LA to old rats improves performance on memory tasks by lowering oxidative damage and improving mitochondrial function.  相似文献   
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