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排序方式: 共有1396条查询结果,搜索用时 15 毫秒
941.
The authors examined genetic and environmental contributions to stability and change in heavy drinking from late adolescence to young adulthood in a sample of 1,152 twin pairs. In men, heavy drinking was similarly heritable at ages 17 (h2=.57) and 20 (h2=.39), and its stability owed primarily to common genetic factors. In women, heavy drinking was less heritable than in men at ages 17 (h2=.18) and 20 (h2=.30) and its stability was primarily due to enduring shared environmental influences. P3 amplitude, an event-related brain potential marker of alcoholism risk, was less predictive of heavy drinking in women than in men, providing further support for the proposition that biological factors have less impact on heavy drinking in young adult women than in young adult men.  相似文献   
942.
This study examined whether survey response rate differed based on the color of the paper the survey was printed on (blue vs green) and presence of a monetary incentive. A 4-page survey on eating disorders was mailed to Division 1A and 1AA college head athletic trainers (N=223) with half of the surveys on blue paper and half on green paper. Half of the athletic trainers (n = 111) received a $1.00 monetary incentive, and half (n = 112) received no monetary incentive. A total of 166 (71%) athletic trainers returned completed surveys. Response rates did not differ based on survey color but did differ based on presence of a monetary incentive. Athletic trainers who received a monetary incentive were significantly more likely than those who did not to return completed surveys (86% vs 63%, respectively).  相似文献   
943.
Outcome measures for clinical drug trials in autism   总被引:1,自引:0,他引:1  
This paper identifies instruments and measures that may be appropriate for randomized clinical trials in participants with autism spectrum disorders (ASDs). The Clinical Global Impressions scale was recommended for all randomized clinical trials. At this point, however, there is no "perfect" choice of outcome measure for core features of autism, although we will discuss five measures of potential utility. Several communication instruments are recommended, based in part on suitability across the age range. In trials where the intention is to alter core features of ASDs, adaptive behavior scales are also worthy of consideration. Several "behavior complexes" common to ASDs are identified, and instruments are recommended for assessment of these. Given the prevalence of cognitive impairment in ASDs, it is important to assess any cognitive effects, although cognitive data from ASD randomized clinical trials, thus far, are minimal. Guidance from trials in related pharmacologic areas and behavioral pharmacology may be helpful. We recommend routine elicitation of side effects, height and weight, vital signs, and (in the case of antipsychotics) extrapyramidal side-effects assessment. It is often appropriate to include laboratory tests and assessments for continence and sleep pattern.  相似文献   
944.
Wang RF 《Cognition》2004,94(2):185-192
Studies have shown that perception of distance, orientation and size can be dissociated from action tasks. The action system seems to possess more veridical, unbiased information than the perceptual/verbal system. The current study examines the nature of the distinction between action and verbal responses in a spatial reasoning task. Participants imagined themselves facing different orientations and either pointed to where other objects would be, or verbally reported their egocentric directions (e.g., "50 degrees to my left"). When using pointing responses, RT and error increased as a function of the angular disparity between the imagined heading and their actual heading. However, when using verbal responses, performance was not affected by angular disparity, suggesting that participants knew the direction of the targets from the imagined perspective but could not point to them directly. The verbal and action systems have fundamentally different information or processes rather than quantitatively different ones.  相似文献   
945.
The Believer     
The author discusses the film The Believer (2001) as illustrative of ambivalence and conflict regarding aggression in the father-son relationship. The biblical story of Abraham and Isaac, a preoccupation of the film's protagonist, is explored in terms of its implications in considering oedipal rivalry themes. Filial conflict regarding the wish to surrender to the father is explored, as are conflicts regarding masculine and feminine identifications. The theme of Jewish self-hatred is discussed.  相似文献   
946.
947.
The human placenta produces corticotrophin-releasing hormone (CRH) in exponentially increasing amounts during pregnancy with peak levels during labour. CRH in human pregnancy appears to be involved in many aspects of pregnancy including placental bloodflow, placental prostaglandin production, myornetrial function, fetal pituitary and adrenal function and the maternal stress axis. Since fetal cortisol levels are associated with pulmonary development and maturity, placental CRH may have an indirect role in fetal development.Although the precise role of placental CRH in the regulation of gestational length and timing of parturition is unclear it appears to be involved in a placental clock. While glucocorticoids inhibit hypothalamic CRH production they stimulate CRH gene expression in the placenta.This difference may allow the fetal and maternal stress axes to influence this placental clock.Maternal CRH levels are elevated in many pathological conditions of pregnancy where fetal well-being is compromised, and in these situations it may act to maintain a stable intrauterine environment. Therefore, CRH appears to link placental function, maternal well-being, fetal well-being and fetal development to the duration of gestation and the timing of parturition.  相似文献   
948.
Using a temporal integration task, subjects in 5 experiments were expected to combine information from temporally separated visual presentations. Evidence from these experiments indicated that perceptual information can be integrated with previously generated and currently maintained visual images to form a representation that contains information from each source. Properties and limitations of this integration process were also explored, including the time required to generated the image, the speed at which percepts were integrated with images, and the capacity of the representation. Implications for theories of visual processing and memory are discussed.  相似文献   
949.
Data are presented on social and vocal learning in cowbirds (Molothrus ater) housed in large aviaries and given more degrees of freedom than in conventional experimental studies. The studies show that social and vocal outcomes are facultative responses to social contexts. Several findings are reviewed: First, cowbirds quickly self-organize into groups by age and sex; second, opportunities to interact across age and sex do exist and affect courtship competence; third, female cowbirds organize themselves differently in the presence and absence of male competition; and fourth, young, naive cowbirds show rapid and differential sensitivity to group dynamics. Taken as a whole, the data show that social Umwelten are dynamic, developmental ecologies.  相似文献   
950.
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