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161.
Vitamin E (α-tocopherol), a lipid-soluble anti-oxidant, prevents the uncontrolled propagation of lipid peroxidation by free radicals. Nevertheless, there is weak or no evidence of a protective effect of previous vitamin E intake on cognitive function in humans. In the present study, we explored the thermosensation model to investigate the possible effects of vitamin E administration on memory behaviors in Caenorhabditis elegans. Administration of 100 and 200 μg/mL of vitamin E had no significant effects on the memory for different time intervals, whereas relatively high concentration (400 μg/mL) of vitamin E exposure shortened the extinction period of the association paradigm (food at 20 °C). Following the UV-irradiation, post-treatment with 200 μg/mL of vitamin E not only retrieved the UV-irradiation-induced memory deficits, but also enhanced the memory functions in UV-irradiating animals. Post-treatment with trace vitamin E could also ameliorate the memory deficits in metal (Al or Pb) exposed worms. In addition, pre-treatment with 200 μg/mL of vitamin E could effectively prevent the occurrence of memory deficits induced by metal exposure and UV-irradiation. Therefore, the close association may exist between trace dietary vitamin E intake and memory behaviors, and a specific response mechanism may be activated after the administration of vitamin E in stress-exposed animals. Moreover, treatment with 200 μg/mL of vitamin E could restore the memory deficits formed in the ncs-1 mutant worms, suggesting that exogenous treatment with trace vitamin E can largely mimic the function of NCS-1 in regulating the memory for thermosensation.  相似文献   
162.
Despite recent social and political advances, most interracial contact is still superficial in nature, and White individuals interact mainly with other Whites. Based on recent mere exposure research, we propose that repeated exposure to Whites may actually increase prejudice. In a series of experiments, White participants were subliminally exposed to White faces or nothing (control) and then completed various explicit and implicit measures of racial attitudes. Exposure to White faces consistently led to more prejudice by making attitudes toward Blacks more negative, rather than by making attitudes toward Whites more positive. A final experiment demonstrated that the pattern of increased prejudice following exposure to Whites was moderated by the strength of participants’ attitudes toward Whites. Only when White attitudes were strong did Black attitudes became more negative after exposure to White faces.  相似文献   
163.
ABSTRACT— Contemporary theories of learning typically assume that learning is driven by prediction errors—in other words, that we learn more when our predictions turn out to be incorrect than we do when our predictions are correct. Results from the recording of electrical brain activity suggest one mechanism by which this might happen; we seem to direct visual attention toward the likely causes of previous prediction errors. This can happen very rapidly—within less than 200 milliseconds of the error-causing object being presented. It is tempting to infer that if learning is driven by prediction errors, then little can be learned in the absence of feedback. Such a conclusion is unwarranted. In fact, the substantial learning that is sometimes the result of simple exposure to objects can also be explained by processes of directing attention toward the likely causes of previous prediction errors.  相似文献   
164.
We estimated childhood risk of developing selected DSM-IV Disorders, including Attention-Deficit Hyperactivity Disorder (ADHD), Oppositional Defiant Disorder (ODD), and Separation Anxiety Disorder (SAD), in children with prenatal cocaine exposure (PCE). Children were enrolled prospectively at birth (n = 476) with prenatal drug exposures documented by maternal interview, urine and meconium assays. Study participants included 400 African-American children from the birth cohort, 208 cocaine-exposed (CE) and 192 non-cocaine-exposed (NCE), who attended a 5-year follow-up assessment and whose caregiver completed the Computerized Diagnostic Interview Schedule for Children. Under a generalized linear model (logistic link), Fisher’s exact methods were used to estimate the PCE-associated relative risk (RR) of these disorders. Our results indicated a modest but statistically robust elevation of ADHD risk associated with increasing levels of PCE (p < 0.05). Binary comparison of CE versus NCE children indicated no PCE-associated RR. Estimated cumulative incidence proportions among CE children were 2.9% for ADHD (vs 3.1% NCE); 1.4% for SAD (vs 1.6% NCE); and 4.3% for ODD (vs 6.8% NCE). Our findings suggest evidence of increased risk of ADHD (but not ODD or SAD) in relation to an increasing gradient of PCE during gestation.  相似文献   
165.
With considerable literature establishing how separate types of violence disrupt the lives of children, there is emerging interest in examining violence across multiple interpersonal domains. This article examines four commonly occurring and frequently researched domains of violence exposure: marital physical aggression, mother-to-youth aggression, father-to-youth aggression, and community violence. A community-based sample of 103 parents and youth provided three waves of data at annual intervals beginning when the youth were aged 9–10. We explored stability of exposure, co-occurrence across different types of violence exposure, and associations with co-occurring risk factors. Approximately 30–45% of youth reported intermittent exposure over the 3 years. In addition to overlap among types of violence exposure within the family, we found overlap between parent-to-youth aggression and community violence, an association that was exacerbated in families where fathers reported high levels of global distress symptoms. Mother-to-youth, father-to-youth, and community violence related to youth behavior problems beyond the contextual risk factors of low income, stressful life events, and parents’ global distress symptoms. These results highlight the importance of examining violence longitudinally, across multiple types, and with attention to contextual factors.  相似文献   
166.
In this article, we describe a theoretical framework for understanding how persistent and extreme exposure to ethnic–political conflict and violence interacts with cognitive, emotional, and self processes to influence children’s psychosocial adjustment. Three recent strands of theorizing guide our approach. First, we focus on how observational and social learning processes combine to influence the development of social-cognitive structures and processes that affect behavior. Second, we focus on the role of developing self and identity processes in shaping the child’s interactions with the world and the consequences of those interactions. Third, we build on the complex systems perspective on development and assume that human development can only be understood accurately by examining how the multiple contexts affecting children and the adults in their lives interact to moderate biosocial factors which predispose individuals to develop in certain directions. We review the recent empirical literature on children’s exposure to ethnic–political violence and we apply the social-cognitive-ecological framework to the empirical findings in this literature. Finally, we propose future directions for research and clinical implications derived from this framework.  相似文献   
167.
采用青少年生活事件量表(ASLEC)、自编震后创伤程度调查表和PTSD自评量表对汶川地震区413名中学生进行问卷调查,探讨震前生活事件、创伤程度对震后心理应激反应的影响。结果表明:中学生PTSD症状有显著的性别差异,女生高于男生;震前生活事件、创伤程度的各维度与PTSD症状反应总分相关显著;学习压力、暴露和丧失程度均对再体验有显著的正向影响;学习压力、受惩罚、其他、暴露和丧失程度对逃避及麻木有显著影响;学习压力、其他、暴露和丧失程度对过度觉醒有显著的正向影响;震前生活事件对PTSD症状反应有重要的影响  相似文献   
168.
Although the relationship between “mere exposure” and attitude enhancement is well established in the adult domain, there has been little similar work with children. This article examines whether toddlers’ visual attention toward pictures of foods can be enhanced by repeated visual exposure to pictures of foods in a parent-administered picture book. We describe three studies that explored the number and nature of exposures required to elicit positive visual preferences for stimuli and the extent to which induced preferences generalize to other similar items. Results show that positive preferences for stimuli are easily and reliably induced in children and, importantly, that this effect of exposure is not restricted to the exposed stimulus per se but also applies to new representations of the exposed item.  相似文献   
169.
Forty-four Israeli security agents employed by the Israeli Government Terrorism Prevention Agency providing security services for the national Israeli airlines and the Israeli Consulate in Los Angeles were administered the Subjective Stress Experience Scale (SSES). This scale measures stress at terrorism-prevention work, past stress during combat exposure, and subjects’ most stressful life events. Results support the hypothesis that terrorism prevention personnel who are also combat veterans appraise their work as less stressful than their noncombat exposed counterparts. Combat veterans also rated their combat experience as significantly more stressful than prevention team member’s other stressful life events. Subjects presented a uniform stress- inoculation effect but, combat veterans of the prevention team were more stress-inoculated than their noncombat exposed counterparts.  相似文献   
170.
We review the effects of maternal cocaine use on the developing human fetus and infant in terms of methodological problems; the physiological action of cocaine on adults and on the developing fetus; the epidemiology of cocaine use; effects on fetal and infant mortality; growth of cocaine-exposed fetuses and infants; physical anomalies; evidence for and against infant withdrawal from cocaine; neurological effects; behavioral effects as shown by the NBAS; findings related to mother-infant interaction and emotional development; and parenting by cocaine-using mothers. Findings in most areas should be considered preliminary due to methodological problems. Published studies of long-term development are not yet available. In general, deleterious consequences of prenatal cocaine exposure are found for some portion of prenatally exposed infants. However, many findings of no difference are also available in methodologically well-controlled studies.  相似文献   
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