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41.
Synapses formed by the olfactory nerve (ON) provide the source of excitatory synaptic input onto mitral cells (MC) in the olfactory bulb. These synapses, which relay odor-specific inputs, are confined to the distally tufted single primary dendrites of MCs, the first stage of central olfactory processing. beta-adrenergic modulation of electrical and chemical signaling at these synapses may be involved in early odor preference learning. To investigate this possibility, we combined electrophysiological recordings with calcium imaging in olfactory bulb slices prepared from neonatal rats and mice. Activation of ON-MC synapses induced postsynaptic potentials, which were associated with large postsynaptic calcium transients. Neither electrical nor calcium responses were affected by beta-adrenergic agonists or antagonist. Immunocytochemical analysis of MCs and their tufted dendrites revealed clear immunoreactivity with antibodies against alpha1A (Cav2.1, P/Q-type) and alpha1B (Cav2.2, N-type), but not against alpha1C (Cav1.2, L-type) or alpha1D (Cav1.3, L-type) calcium channel subunits. Moreover, nimodipine, a blocker of L-type calcium channels, had no effect on either electrical or calcium signaling at ON-MC synapses. In contrast to previous evidence, we concluded that in neonatal rats and mice (P5-P8), mitral cells do not express significant amounts of L-type calcium channels, the calcium channel type that is often targeted by beta-adrenergic modulation. The absence of beta-adrenergic modulation on either electrical or calcium signaling at ON-MC synapses of neonatal rats and mice excludes the involvement of this mechanism in early odor preference learning.  相似文献   
42.
This study examined the emergence of cultural self-constructs as reflected in children's remembered and conceptual aspects of the self. European American and Chinese children in preschool through 2nd grade participated (N=180). Children each recounted 4 autobiographical events and described themselves in response to open-ended questions. American children often provided elaborate and detailed memories focusing on their own roles, preferences, and feelings; they also frequently described themselves in terms of personal attributes, abstract dispositions, and inner traits in a positive light. Chinese children provided relatively skeletal accounts of past experiences that centered on social interactions and daily routines, and they often described themselves in terms of social roles, context-specific characteristics, and oven behaviors in a neutral or modest tone. Findings are discussed in light of the self as a constructed meaning system of culture that emerges early in life.  相似文献   
43.
Howard DE  Wang MQ 《Adolescence》2003,38(151):519-533
The prevalence of dating violence, as well as its association with psychosocial factors, was examined among a nationally representative sample of 9th- through 12th-grade U.S. boys (N = 7,434) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals (CI) were examined. Multivariate logistic regression was used to examine all significant independent variables from the univariate models. Adjusted OR and 95% CI were examined to assess the significance of these relationships. In terms of prevalence, 9.13% of the boys reported physical dating violence. Boys who reported sad/hopeless feelings (OR = 1.68), had attempted suicide (OR = 2.22), reported fighting (OR = 1.81), had multiple sex partners (OR = 3.53), and reported nonuse of condoms (OR = 1.66) were more likely to report physical dating violence. These findings indicate that physical dating violence among adolescent boys may be a more serious problem than has previously been recognized. It was concluded that intervention programs should include a focus on boys as not only perpetrators but also recipients of dating violence.  相似文献   
44.
Howard DE  Wang MQ 《Adolescence》2003,38(149):1-14
The prevalence of dating violence, as well as its relationship to potential risk factors, was examined among a nationally representative sample of 9th-through 12th-grade U.S. females (N = 7,824) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals were examined, and multivariate logistic regression analysis was conducted to identify the most significant risk factors. It was found that nearly one in ten of the adolescent girls reported dating violence. Twelfth-grade girls had the highest prevalence of dating violence. Girls who were victims of dating violence were more likely to be involved in other violent behaviors, to report extreme sadness and suicidal actions, to use illicit substances, and to engage in risky sexual behavior. Multivariate analysis revealed that dating violence was associated with sad/hopeless feelings (OR = 2.13), binge drinking (OR = 1.96), cocaine or inhalant use (OR = 2.90), multiple sex partners (OR = 2.38), nonuse of condoms (OR = 1.53), and ethnicity, specifically being Black (OR = 2.32) or Hispanic (OR = 1.82). These findings provide further evidence that there is a clustering of risk factors among certain adolescents, specifically girls who experience dating violence.  相似文献   
45.
This research uses a combination of text mining, co-word analysis, and social network analysis (SNA) to review 132 international sales and sales management (ISSM) articles published between 1980 and 2017. The study provides a unique view of the past and future of ISSM research and provides three principal contributions. First, from a social network–analytic perspective, it offers a unique examination of the ways ISSM research topics are interconnected, as reflected by keyword network structure. Second, by conducting SNA across two periods (1980–1999 and 2000–2017) and examining the changes in network centrality measures, the study offers initial insights into the evolving nature of the ISSM literature. Third, the study reports keyword network disconnections (i.e., structural holes) to propose a fruitful agenda for future ISSM research. Taken together, this research offers a current perspective of the ISSM research domain's evolving nature.  相似文献   
46.
Do false memories last? And do they last as long as true ones? This study investigated whether experimentally created false memories would persist for an extended period (one and a half years). A large number of subjects (N = 342) participated in a standard three‐stage misinformation procedure (saw the event slides, read the narrations with misinformation, and then took the memory tests). The initial tests showed that misinformation led to a significant amount of false memory. One and a half years later, the participants were tested again. About half of the misinformation false memory persisted, which was the same rate as for true memory. These results strongly suggest that brief exposure to misinformation can lead to long‐term false memory and that the strength of memory trace was similar for true and false memories. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
47.
黎昕  赵妍妍 《哲学研究》2012,(5):32-41,128
<正>朱子学自12世纪创建以来,不仅极大地影响了中华民族的思想文化,而且先后风靡韩国、日本,逐渐成为东亚世界的主流思想。虽然朱子学自16世纪末17世纪初传入欧洲后有相当长一段时间未能作为一门独立学说获得长足发展①,在北美更是经历了相当长时间的沉寂期,但最终在当代(尤其是  相似文献   
48.
2010年发生于武汉的超女王贝整容致死事件,使中国的医疗整形美容行业受到质疑.相关医学学会组织的职能缺失是事件引起社会关注的重要原因之一.通过梳理该事件发生发展的全过程,分析医学学会的作用,借以指出医学学会在制度建设和职业精神建设等方面存在的问题,并提出完善医学学会职能的建议.  相似文献   
49.
This study examines the effectiveness of bibliotherapy for low sexual desire among women, which is the most frequent sexual concern brought to counselors. Forty-five women responded to an advertisement for participation in a study on low sexual desire and were assigned to either the intervention or the wait-list control group. The intervention group completed the Hurlbert Index of Sexual Desire (HISD; Apt & Hurlbert, 1992) and the Female Sexual Function Index (FSFI; R. Rosen et al., 2000), read the self-help book under study in 6 weeks, and completed the measures a second time. The control group completed the same measures 6 weeks apart. Results demonstrated that the intervention group made statistically greater gains over time as compared with the control group on measures of sexual desire (HISD and FSFI Desire subscale), sexual arousal (FSFI Arousal subscale), sexual satisfaction (FSFI Satisfaction subscale), and overall sexual functioning (FSFI Total Score). A subset of participants in the intervention group participated in a 7-week follow-up study, and these participants maintained their gains in sexual desire and overall sexual functioning. Findings have important implications for future research on the efficacy of bibliotherapy generally and for low sexual desire specifically. Results also have vital implications for the treatment of low sexual desire.  相似文献   
50.
This study examines the relational model of self-supporting personality, enacted social support, and perceived social support in a sample of 482 Chinese high school students using the Self-Supporting Personality Scale for Adolescent Students (SSPS-AS), the Social Support Rating Scale (SSRS), and the Multidimensional Scale of Perceived Social Support (MSPSS). Results from the cross-sectional structural equation analyses revealed that interpersonal initiative, interpersonal openness, personal openness and personal initiative predicted perceived social support through the mediating role of enacted social support, while interpersonal responsibility, interpersonal flexibility, and personal initiative predicted perceived social support directly. Thus, the hypothesized relational model of personality, enacted social support, and perceived social support was supported. The positive relational schema may be the main underpinning of the relation of self-supporting personality, enacted social support, and perceived social support. Culture also may influence the relation.  相似文献   
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