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21.
In three separate experiments a total of 85 male and female university students were exposed within a Ganzfeld setting to weak (1 mG, 100 nT), complex magnetic field patterns. They were applied across the temporal lobes and generated by computer software. When the patterns were rotated spatially over the temporal lobes the numbers of subjective experiences that simulate possible temporal lobe signs and symptoms were markedly increased and qualitatively more extreme than those evoked when the fields were not rotated. A 16 Hz pulsed square wave generated more experiences of thought intrusion than a 4 Hz wave. A positive-feedback ringing wave presented at 4 Hz evoked more visual memories and images than the mirror image of the same wave; the effect was only apparent when the subject's quantitative scores for possible temporal lobe signs was covaried. Only those subjects who displayed above average temporal lobe signs and were exposed to a burst-firing wave pattern for one second once every 4 seconds (a condition intended to release endogenous opiates), reported more emotional perturbations when the state was disrupted relative to subjects who were exposed continuously to the same pattern. The results indicate that a person's temporal lobe profile affects the types and intensities of experiences that are reported when very weak magnetic fields are applied through the human brain.  相似文献   
22.
Youth experience adversity that increases their risk for immediate and long-term health consequences. Resilience has traditionally been conceptualized as an internal disposition or trait that supports youth to overcome that risk and avoid the negative impact on their health and wellbeing. However, this model of resilience overemphasizes the role of the individual and their capacity to control their environment, while minimizing the integral role of relational, social, structural, and cultural contexts in which they live. Instead, social ecological resilience (SER) emphasizes the influence of social and environmental factors on individual processes and outcomes and offers different pathways for preventive interventions to promote youth health and wellbeing. Within preventive medicine, it is important for researchers and practitioners to understand the processes that support or impede SER, particularly in youth when adversity can impact health throughout the lifespan. The purpose of this review was to examine the contributions and scope of the SER model in research on youth, with the goal of advancing SER-informed research and interventions within preventive medicine. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach as a guiding framework, we conducted a narrative review of the literature. The review characterizes 37 existing studies across the fields of education, psychology, and social work in terms of topic, focal population, methods, use of SER, and implications. We conclude with recommendations for future applications of SER to promote the health and wellbeing of youth.  相似文献   
23.
《Chronobiology international》2013,30(9):1183-1191
While important changes in circadian rhythms take place during adolescence and young adulthood, it is unclear how circadian profiles during this period relate to emerging mental disorders. This study aimed to: (i) characterise morningness–eveningness preference in young people with primary anxiety, depression, bipolar or psychotic disorders as compared to healthy controls, and (ii) to investigate associations between morningness–eveningness preference and the severity of psychiatric symptoms. Four hundred and ninety-six males and females aged between 12 and 30 years were divided into five groups according to primary diagnosis. The Hamilton Depression Rating Scale and the Brief Psychiatric Rating Scale were administered by a research psychologist and participants completed the Kessler Psychological Distress Scale and the Horne–Östberg Morningness–Eveningness Questionnaire (ME). ME scores were significantly lower (i.e. higher levels of “eveningness”) in all patient diagnosis subgroups compared to the control group. The psychosis group had higher ME scores than the depression and anxiety groups. Compared to the control group, the anxiety, depression and bipolar subgroups had a significantly higher proportion of “moderate evening” types, with a similar trend for the psychosis group. The proportion of “extreme evening” types was significantly higher in the anxiety and depression subgroups than in the control group. Lower ME scores correlated with worse psychological distress in males from the bipolar group. Lower ME scores correlated with higher depression severity in females with depression and in males with bipolar disorder. These results suggest that young persons with various mental disorders, especially those with affective disorders, present with a stronger “eveningness” preference and higher rates of evening chronotypes than healthy controls from the same age group. Later chronotypes were generally associated with worse psychological distress and symptoms severity. These associations were modulated by sex and primary diagnosis.  相似文献   
24.
For more than 30 years, the US National Science Foundation's Research Experiences for Undergraduates (REU) program has supported thousands of undergraduate researchers annually and provides many students with their first research experiences in field ecology or evolution. REUs embed students in scientific communities where they apprentice with experienced researchers, build networks with their peers, and help students understand research cultures and how to work within them. REUs are thought to provide formative experiences for developing researchers that differ from experiences in a college classrooms, laboratories, or field trips. REU assessments have improved through time but they are largely ungrounded in educational theory. Thus, evaluation of long‐term impacts of REUs remains limited and best practices for using REUs to enhance student learning are repeatedly re‐invented. We describe how one sociocultural learning framework, cultural–historical activity theory (CHAT), could be used to guide data collection to characterize the effects of REU programs on participant's learning in an educationally meaningful context. CHAT embodies a systems approach to assessment that accounts for social and cultural factors that influence learning. We illustrate how CHAT has guided assessment of the Harvard Forest Summer Research Program in Ecology (HF‐SRPE), one of the longest‐running REU sites in the United States. Characterizing HF‐SRPE using CHAT helped formalize thoughts and language for the program evaluation, reflect on potential barriers to success, identify assessment priorities, and revealed important oversights in data collection.  相似文献   
25.
In the world of higher education, one of the struggles instructors face in the classroom is engaging students in the material. A second discussion in higher education pedagogy is how to weigh content versus activity in the science classroom. How should college teaching be set up when students now have every fact ever found at their fingertips on a device no larger than a half sandwich? What is the correct balance in the classroom between content/ knowledge and activity? As instructors grapple with these questions, a new type of learning experience called the Course Based Undergraduate Research Experience (CURE) has been developed, whereby students engage in an authentic research question in a classroom and laboratory setting. CUREs have been shown to be effective learning experiences for students but can be difficult to implement. Saccharomyces cerevisiae is a versatile and easy to use organism in the classroom that can be used for a wide variety of classroom activities. Described herein are a number of ways an instructor can use yeast in the classroom for authentic research experiences, especially focused towards a CURE.  相似文献   
26.
Prospective evaluation of youths with early psychotic‐like experiences can enrich our knowledge of clinical, biobehavioral and environmental risk and protective factors associated with the development of psychotic disorders. We aimed to investigate the predictors of persistence or worsening of psychosis spectrum features among US youth through the first large systematic study to evaluate subclinical symptoms in the community. Based on Time 1 screen of 9,498 youth (age 8‐21) from the Philadelphia Neurodevelopmental Cohort, a subsample of participants was enrolled based on the presence (N=249) or absence (N=254) of baseline psychosis spectrum symptoms, prior participation in neuroimaging, and current neuroimaging eligibility. They were invited to participate in a Time 2 assessment two years on average following Time 1. Participants were administered the Structured Interview for Prodromal Syndromes, conducted blind to initial screen status, along with the Schizotypal Personality Questionnaire and other clinical measures, computerized neurocognitive testing, and neuroimaging. Clinical and demographic predictors of symptom persistence were examined using logistic regression. At Time 2, psychosis spectrum features persisted or worsened in 51.4% of youths. Symptom persistence was predicted by higher severity of subclinical psychosis, lower global functioning, and prior psychiatric medication at baseline. Youths classified as having psychosis spectrum symptoms at baseline but not at follow‐up nonetheless exhibited comparatively higher symptom levels and lower functioning at both baseline and follow‐up than typically developing youths. In addition, psychosis spectrum features emerged in a small number of young people who previously had not reported significant symptoms but who had exhibited early clinical warning signs. Together, our findings indicate that varying courses of psychosis spectrum symptoms are evident early in US youth, supporting the importance of investigating psychosis risk as a dynamic developmental process. Neurocognition, brain structure and function, and genomics may be integrated with clinical data to provide early indices of symptom persistence and worsening in youths at risk for psychosis.  相似文献   
27.
The transdiagnostic expression of psychotic experiences in common mental disorder (anxiety/depression/substance use disorder) is associated with a poorer prognosis, and a small minority of people may indeed develop a clinical picture that meets criteria for schizophrenia. However, it appears neither useful nor valid to observe early states of multidimensional psychopathology in young people through the “schizo”‐prism, and apply misleadingly simple, unnecessary and inefficient binary concepts of “risk” and “transition”. A review of the “ultra‐high risk” (UHR) or “clinical high risk” (CHR) literature indicates that UHR/CHR samples are highly heterogeneous and represent individuals diagnosed with common mental disorder (anxiety/depression/substance use disorder) and a degree of psychotic experiences. Epidemiological research has shown that psychotic experiences are a (possibly non‐causal) marker of the severity of multidimensional psychopathology, driving poor outcome, yet notions of “risk” and “transition” in UHR/CHR research are restrictively defined on the basis of positive psychotic phenomena alone, ignoring how baseline differences in multidimensional psychopathology may differentially impact course and outcome. The concepts of “risk” and “transition” in UHR/CHR research are measured on the same dimensional scale, yet are used to produce artificial diagnostic shifts. In fact, “transition” in UHR/CHR research occurs mainly as a function of variable sample enrichment strategies rather than the UHR/CHR “criteria” themselves. Furthermore, transition rates in UHR/CHR research are inflated as they do not exclude false positives associated with the natural fluctuation of dimensional expression of psychosis. Biological associations with “transition” thus likely represent false positive findings, as was the initial claim of strong effects of omega‐3 polyunsatured fatty acids in UHR samples. A large body of UHR/CHR intervention research has focused on the questionable outcome of “transition”, which shows lack of correlation with functional outcome. It may be more productive to consider the full range of person‐specific psychopathology in all young individuals who seek help for mental health problems, instead of “policing” youngsters for the transdiagnostic dimension of psychosis. Instead of the relatively inefficient medical high‐risk approach, a public health perspective, focusing on improved access to a low‐stigma, high‐hope, small scale and youth‐specific environment with acceptable language and interventions may represent a more useful and efficient strategy.  相似文献   
28.
Predator/parasitoid functional response is one of the main tools used to study predation behavior, and in assessing the potential of biological control candidates. It is generally accepted that predator learning in prey searching and manipulation can produce the appearance of a type III functional response. Holling proposed that in the presence of alternative prey, at some point the predator would shift the preferred prey, leading to the appearance of a sigmoid function that characterized that functional response. This is supported by the analogy between enzyme kinetics and functional response that Holling used as the basis for developing this theory. However, after several decades, sigmoidal functional responses appear in the absence of alternative prey in most of the biological taxa studied. Here, we propose modeling the effect of learning on the functional response by using the explicit incorporation of learning curves in the parameters of the Holling functional response, the attack rate (a), and the manipulation time (h). We then study how the variation in the parameters of the learning curves causes variations in the shape of the functional response curve. We found that the functional response product of learning can be either type I, II, or III, depending on what parameters act on the organism, and how much it can learn throughout the length of the study. Therefore, the presence of other types of curves should not be automatically associated with the absence of learning. These results are important from an ecological point of view because when type III functional response is associated with learning, it is generally accepted that it can operate as a stabilizing factor in population dynamics. Our results, to the contrary, suggest that depending on how it acts, it may even be destabilizing by generating the appearance of functional responses close to type I.  相似文献   
29.
Race talk within discourse analytic traditions have largely focused on the discursive construction of racism in majority groups. This article extends this work by examining how Black adults discursively engaged in race talk. Across focus groups, two conversations emerged: explanations of racialized experiences and how racialized experiences should be dealt with. In explanations of racialized experiences, participants highlighted their own negative behaviours or constructed experiences as imprecise or an artefact of ignorance. These discourses functioned to circumvent inequitable relations premised on White normativity. In explanations of how racialized experiences should be dealt with, participants constructed themselves as having responsibilities, downplayed their racialized experiences or framed them as inevitable. Each of these discourses functioned to construct racialization as something that could be corrected through good behaviour or they placed ideological limits for what is possible for Blacks in society. Implications for the existing literature on race talk are discussed.  相似文献   
30.
Over the last two decades, lay and professional interest in Britain's ‘mixed-race’ population has markedly increased, following dramatic growth in mixing and mixedness. As is often the case with new phenomena, agencies in the sphere of popular culture have stepped in to offer the wider public interpretative representations of this ‘new’ group. Drawing on challenging concepts, like demographic growth rates and projections, the family ‘norm’, the ostensible benefits of heterozygosity, and the drawbacks of claimed ‘in-betweenness’, they have offered us a picture of the ‘mixed-race’ population that is sometimes at variance with lived experiences or the harder image of statistical reality. Social representation theory is used to explore the limitations of these representations and to offer a number of counter-narratives that are grounded in the evidence base.  相似文献   
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