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31.
Lawler CP Croen LA Grether JK Van de Water J 《Mental retardation and developmental disabilities research reviews》2004,10(4):292-302
The potential role of environmental factors in autism spectrum disorders (ASD) is an area of emerging interest within the public and scientific communities. The high degree of heritability of ASD suggests that environmental influences are likely to operate through their interaction with genetic susceptibility during vulnerable periods of development. Evaluation of the plausibility of specific neurotoxicants as etiological agents in ASD should be guided by toxicological principles, including dose-effect dependency and pharmacokinetic parameters. Clinical and epidemiological investigations require the use of sufficiently powered study designs with appropriate control groups and unbiased case ascertainment and exposure assessment. Although much of the existing data that have been used to implicate environmental agents in ASD are limited by methodological shortcomings, a number of efforts are underway that will allow more rigorous evaluation of the role of environmental exposures in the etiology and/or phenotypic expression of the disorder. Surveillance systems are now in place that will provide reliable prevalence estimates going forward in time. Anticipated discoveries in genetics, brain pathology, and the molecular/cellular basis of functional impairment in ASD are likely to provide new opportunities to explore environmental aspects of this disorder. 相似文献
32.
This study examined the relations between maternal criticism and externalizing and internalizing symptoms in adolescents who varied in their risk for psychopathology. Both maternal-effects and child-effects models were examined. The sample consisted of 194 adolescents (mean age = 11.8~years) and their mothers; 146 mothers had a history of depressive disorders and 48 did not. When adolescents were in 6th and 8th grade, maternal criticism was measured with the five-minute speech sample and adolescents symptoms were assessed with the Child Behavior Checklist. Maternal criticism was significantly associated with both adolescents externalizing and internalizing symptoms, beyond the contribution of the chronicity/severity of mothers depression history. Maternal criticism did not mediate the relation between maternal depression and adolescent symptoms. In contrast, adolescent externalizing behaviors mediated the relation between chronicity/severity of maternal depression history and maternal criticism in 6th grade. Prospective analyses showed that adolescents externalizing symptoms in 6th grade significantly predicted maternal criticism in 8th grade, controlling for maternal depression history and prior maternal criticism. Results are discussed in terms of the importance of examining child-effects models in studies of maternal criticism. 相似文献
33.
老年甲状腺结节的诊治经验 总被引:1,自引:0,他引:1
介绍笔者及科室老年甲状腺结节的诊治经验,对2003年1月至2009年12月期间共收治的144例年龄大于60岁的老年甲状腺结节患者进行分析和总结。老年甲状腺结节以多发为主;压迫症状、异物和不适感、继发性甲状腺功能亢进是老年甲状腺结节患者主要的手术指证;术中发现喉返神经和甲状旁腺有脂肪沉着;病理方面良性结节的钙化率较高;患者术后切口水肿比较明显;暂时性低钙血症的发生率较高;虽然术前麻醉ASA评分较低,但术后心肺并发症的发生率并未上升。老年甲状腺结节患者以全麻为宜,最好采用双甲近全切除术,这不仅可避免术后复发和再次手术率,更可减少甲状腺素制剂的用量,减少药物副作用。 相似文献
34.
Summary Network models of semantic memory assume implicitly or explicitly that the degree of activation of a node is a monotonic function of the total amount of excitation reaching that node from all sources. For example, the activation level of the node representing apple should be greater if it is receiving excitation due to the activation of the nodes for fruit and pear than if only one of these neighboring nodes is activated. This notion was tested by presenting semantic primes 80 ms or 320 ms before a letter string (e.g., apple or ipple) requiring a lexical decision. The prime stimuli consisted of a pair of simultaneous items that were identical in the single prime condition (e.g., fruit/fruit or pear/pear) or different in the double prime condition (e.g., fruit/pear or pear/fruit), and were either related (target = apple) or unrelated (target = copper) to the target, or neutral. As predicted by the summation of semantic activation assumption of network models there was a larger priming effect (in the 320 ms SOA condition) following the simultaneous activation of two related nodes than following the activation of only one node.This research was supported by grants to the first author from the Natural Sciences and Engineering Research Council of Canada. 相似文献
35.
Although the relationships between procedural justice climate and organizational citizenship behaviors have been examined in recent years, little research has explored the mechanism by which procedural justice climate shapes individual employee prosocial behaviors in the workplace. The purpose of this study was to examine the mediating role of a group-level cooperative norm on the relationships between the group-level procedural justice climate and individual-level organizational citizenship behaviors. The survey involved 45 work groups in four different industry fields in Taiwan, including manufacturing, technology, banking, and insurance, and each of the groups was composed of one supervisor and three subordinates. Cross-level analyses using hierarchical linear modeling (HLM) indicated that the cooperative norm fully mediated the relationship between procedural justice climate and individual helping behaviors. Procedural justice climate indirectly affects individual helping behaviors through their effects on the cooperative norm. 相似文献
36.
The present study aimed to extend the generality of the construct of gender role stress (GRS) to Chinese samples. Specific objectives included (1) devising Chinese versions of the Masculine Gender Role Stress Scale (MGRS) and Feminine Gender Role Stress Scale (FGRS) developed by Eisler and his colleagues (2) examining the relationship between GRS and gender role orientation, and (3) evaluating the concurrent validity of GRS by correlating it with a measure of health adjustment. Fifty-one male and 58 female Chinese college students in Hong Kong participated in Study 1, which aimed to develop Chinese versions of the two GRS scales. Similar to Americans, Chinese male students scored higher on the MGRS scale, but lower on the FGRS scale than Chinese female students. Students' scores on the two GRS scales were independent from their global ratings of stereotypic masculinity and femininity. A second sample, consisting of 46 male and 73 female Chinese nurses, was recruited for Study 2, which evaluated the association between GRS and health adjustment. As hypothesized, a high level of MGRS or FGRS was positively related to a high level of health and mental health disturbances for both male and female nurses.This study was funded in part by the Asia Scholarship for Research on Women 1992/93 of the United Board for Christian Higher Education. The authors would like to thank Professor Richard M. Eisler for his permission to translate the MGRS and FGRS scales into Chinese, and the Association of Hong Kong Nurses for their assistance in data collection. 相似文献
37.
沿着安德森等人开创的方向,我们将分析性公理系统从经典逻辑推向模态逻辑,所定义的广义谢弗竖混合了模态词和广义析舍。在这篇论文中,我们给出常见的正规模态逻辑的分析性公理系统及其强完全性定理和插值定理,并讨论演绎关系的性质:单调性和切割性。 相似文献
38.
39.
There is considerable evidence that, when recalling past events, Westerners exhibit greater episodic specificity than East Asians and women exhibit greater episodic specificity than men. Yet it is unknown whether the same cultural and gender differences are true for future events. In the present study 209 European American and Chinese young adults were asked to recall past personal events and imagine future personal events occurring in varied time periods (i.e., 1 week, 1 year, 10-15 years). Regardless of time period, European Americans consistently produced more specific details than Chinese for future events than they did for past events, and women produced more specific details than men for both past and future events. These findings provide additional support for the constructive-episodic-simulation hypothesis, and shed new light on the influence of culture and gender on episodic thinking. 相似文献
40.
Chin-Wei Chang Hung-Yi Hsiao Chieh-Hsin Tang Ying-Ji Chuang Ching-Yuan Lin 《Journal of psycholinguistic research》2010,39(1):21-33
The current study applies semantic differential to explore the semantic perception of emergency signs, in an attempt to analyze
the meanings of emergency signs in regard to the psychological exigencies of the general public. The results indicate that
problems concerning recognition accuracy have been observed, but also that the evaluation of the semantic meaning of the signs
is positive. However, a number of emotional factors also emerge, indicating that if improvements should be made to the existing
emergency signs, it would better facilitate evacuation in the event of an emergency. As for the design guidelines, the emergency
signs should be readily recognizable and have a single meaning. Multiple symbolic meanings should be eliminated. Concrete
design guidelines include: (a) safety movement, (b) clarity, and (c) safety. To avoid confusion in sign recognition, in addition
to the improvements made based on the abovementioned guidelines, educational promotional activities carried out by the government
would also prove very beneficial. 相似文献