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281.
结核病诊治进展与科技革命   总被引:2,自引:0,他引:2  
现代科技革命极大地促进了结核病各方面的发展.微生物学和免疫学的发展,揭示了结核病的病因、发病机制、病理生理的本质,分子生物学技术使结核病的基础研究不仅停留在器官、细胞水平,而是深入到蛋白质、核酸、基因的水平;基因治疗的方法可望从根本上治疗结核病.高新技术的产物如X线照片、电子计算机断层扫描、纤维支气管镜检查和新药的出现等极大地提高了临床诊治的能力.借助于各种先进的医疗设备而进行精确的诊断,基因治疗将成为一种崭新的治疗手段.  相似文献   
282.
It was recently demonstrated that detecting target objects (e.g., animals) in natural scenes can be done in a dual-task paradigm, in the near absence of spatial attention. Under the same conditions, subjects were unable to perform apparently simpler tasks involving synthetic stimuli (e.g., discriminating randomly rotated Ts and Ls, or a bisected colour disc and its mirror image). Classical theories predict that attention is more critical for the recognition of complex stimuli that cannot be easily separated on a single feature dimension. Therefore, these puzzling results have raised a number of questions. If it is not the complexity of a stimulus, what then determines the recognition task's attentional requirements? How does this differ between natural and artificial stimuli? What can these observations tell us about the mechanism of natural scene processing as well as its relation to attention? Here we show that removing colour information, or doubling the amount of information to be analysed, failed to make the natural scene categorization tasks significantly more “attention demanding”. Conversely, increasing discriminability or predictability did not diminish the need for attention in the case of synthetic stimuli. However, when the familiar letters, such as Ts or Ls, were presented upright, full attention was no longer required for discrimination. This suggests that familiarity and meaningfulness might be among the factors that determine attentional requirements for both natural and synthetic stimuli.  相似文献   
283.
ABSTRACT

This study investigated the association between exercise type and inhibition of prepotent responses and error detection. Totally, 75 adults (M = 68.88 years) were classified into one of three exercise groups: those who were regular participants in open- or closed-skill forms of exercise, and those who exercised only irregularly. The participants completed a Stroop and task-switching tasks with event-related brain potentials (ERPs) recorded. The results revealed that regular exercisers displayed faster reaction times (RTs) in the Stroop task compared with irregular exercisers. The open-skill exercisers exhibited smaller N200 and larger P300a amplitudes in the Stroop task compared with irregular exercisers. Furthermore, the open-skill exercisers showed a tendency of shorter error-related negativity latencies at the task-witching test. The findings suggest that older adults may gain extra cognitive benefits in areas such as inhibition functioning and error processing from participating in open-skill forms of physical exercises.  相似文献   
284.
ABSTRACT

Using faces as the priming stimuli, the present study explored the influence of facial expressions on the activation of gender stereotypes using a lexical decision paradigm. Experiment 1 explored the activation of gender stereotypes when the facial primes contained only gender information. The results showed that gender stereotypes were activated. In Experiment 2, the facial primes contained both gender category and expression information. The results indicated that gender stereotypes were not activated. Experiment 3 required the participants to make emotion, gender, or impression decisions concerning the facial primes before the lexical decision task. The results showed that gender stereotypes were not activated in emotion and impression decisions conditions, whereas stereotypes were activated in gender decisions condition. These finding suggest that facial expressions can inhibit automatic activation of gender stereotypes, unless the perceivers perform gender categorization processing to prime faces intentionally.  相似文献   
285.
A process is described for the fabrication of opal-like thin films by controlling a solid–liquid interface moving at an inclined glass substrate. A special airflow is adopted to control solvent evaporation. SEM images and photographs show that the films, composed of polystyrene spheres, are coloured, flat, uniform, packed multilayers, and are well arrayed over a large scale. The ordered domains range in size from 10 to 15?µm. The spheres in suspension crystallized, caused by an intense interaction between the spheres on the boundary between the suspension and the substrate. A wide photonic band gap is observed in the normal-incidence transmission spectra of the films fabricated by this method. Cracks and defects in the films are examined and discussed.  相似文献   
286.
Molecular dynamics simulations of nanoscale multilayered Cu/Ag metals have been conducted under uniaxial tensile straining to elucidate the out-of-plane deformation behaviour relevant to tensile spallation experiments. In nanolayers with pristine architectures, plastic dissipation prior to crack nucleation is suppressed owing to the high hydrostatic tensile stress state. The presence of sources for micro-twinning partials, such as micro-cracks or columnar grain boundaries, result in abundant deformation twin lamellae across multiple Cu/Ag interlayers. Plastic recovery is observed during unloading of the nanolayers.  相似文献   
287.
This study had two objectives. The first was to examine the relationship between thinking styles and self‐esteem. The second objective was to investigate the relationship of the participants' extracurricular experiences to both thinking styles and self‐esteem. Seven‐hundred and ninety‐four university students from Hong Kong participated in the study. Participants responded to the Thinking Styles Inventory (Sternberg & Wagner, 1992) and the Self‐Esteem Inventory (Adult Form, Coopersmith, 1981) as well as to a questionnaire designed to elicit both personal and situational characteristics. It was found that thinking styles and self‐esteem are statistically related. Meanwhile, both thinking styles and self‐esteem are statistically related to the participants' extracurricular experiences. Implications of these findings for teachers are discussed.  相似文献   
288.
Relatively little is known about the potential interplay between genetic and environmental influences on attention-deficit/hyperactivity disorder (ADHD), including gene-environment interaction (G×E). There is evidence that parenting behavior interacts with offspring genotype in the development of externalizing problems, but studies have largely focused on explicit maltreatment rather than differentiated measures of parenting behavior, including positive and negative parenting. We tested the interactive effects of the 30-base pair variable number tandem repeat (VNTR) polymorphism of the monoamine oxidase A gene (MAO-A) with positive and negative parenting behavior on parent- and teacher ratings of inattention and hyperactivity symptoms among 150 6–9 year-old boys with and without ADHD. Negative parenting predicted parent and teacher ratings of inattention symptoms, but only among boys with high-activity MAO-A genotype. MAO-A genotype did not moderate the association of positive parenting and parent- and teacher ratings of ADHD. We discuss the potential role of interactive exchanges between parenting behavior and child genotype in the development and persistence of ADHD and related behavior problems.  相似文献   
289.
Individuals with low self-esteem have been shown to exhibit an attentional bias for social rejection cues. The present study investigated whether individuals with low self-esteem would demonstrate greater reactivity to rejection-related stimuli during an attention shifting task than was exhibited by those with high self-esteem. Individuals with low self-esteem showed higher amplitude event-related potentials (ERPs) in response to rejection cues than was observed for those with high self-esteem. These results suggest that individuals with low self-esteem allocate more attentional resources to rejection cues than those with high self-esteem. Discussion will focus on the implications of these findings for understanding the connection between low self-esteem and social rejection.  相似文献   
290.
Hu Z  Zhang R  Zhang Q  Liu Q  Li H 《Brain and language》2012,121(1):70-75
Previous studies have found a late frontal-central audiovisual interaction during the time period about 150-220 ms post-stimulus. However, it is unclear to which process is this audiovisual interaction related: to processing of acoustical features or to classification of stimuli? To investigate this question, event-related potentials were recorded during a words-categorization task with stimuli presented in the auditory-visual modality. In the experiment, congruency of the visual and auditory stimuli was manipulated. Results showed that within the window of about 180-210 ms post-stimulus more positive values were elicited by category-congruent audiovisual stimuli than category-incongruent audiovisual stimuli. This indicates that the late frontal-central audiovisual interaction is related to audiovisual integration of semantic category information.  相似文献   
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