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151.

High-angle annular dark-field scanning transmission electron microscopy has been employed to study partially decomposed Al-3 at.% Ag. After solutionizing at 550°C and quenching to room temperature, samples of an Al-3 at.% Ag single crystal were aged for short times at 105, 140 and 180°C. Independent of the ageing temperature for these early stages, Guinier-Preston zones with a diameter of about 3 nm are found. Most of these zones consist of a silver-depleted core surrounded by a silver-rich shell. The shell structure is not uniformly pronounced. Irregularly shaped Guinier-Preston zones are common, but the shell structure dominates. No indication of different structures of the Guinier-Preston zones in Al-3 at.% Ag was found after short ageing at the three different temperatures. The shell model for Guinier-Preston zones in aluminium-rich Al-Ag alloys, which was previously proposed on the basis of X-ray and neutron scattering experiments, is thus appropriate to describe the structure of the Guinier-Preston zones in the early stages of the decomposition.  相似文献   
152.
1. The electromyographic potentials arising from masticatory movements were picked up by electrodes chronically implanted in the brains of eight rats. The rats had been trained in a Skinner box to press a lever for food reinforcement on a 100 per cent schedule. Lever and food cup were separated by 180[ddot] in a cylindrical metal box one foot in diameter.

2. The problem was to determine whether thoroughly trained animals would show AGRs as determined by the presence of electromyographic potentials when, in the course of pressing, food was suddenly withheld. Only two of the eight animals gave an AGR during the extinction process, and in one of these the phenomenon was minimal.

3. In the discussion it is pointed out that the absence of AGRs in the animals was possibly related to the short time interval intervening between depression of the lever and securing the food-pellet reward.  相似文献   
153.
Subjects (N = 164) were divided into four groups on the basis of their driving records: no accidents or moving violations, two or more violations, one or more accidents, and no accidents. They were compared on various personality, attitudinal, drug usage, and biographical variables. The less safe drivers scored significantly higher on a sensation-seeking scale; were more likely to have experimented with such drugs as marijuana, hashish, amphetamines, LSD, etc.; attended religious services less often; and were less likely to own their residences. There were also differences in political attitudes and life-style preferences among the groups.  相似文献   
154.
Prominent theories of action recognition suggest that during the recognition of actions the physical patterns of the action is associated with only one action interpretation (e.g., a person waving his arm is recognized as waving). In contrast to this view, studies examining the visual categorization of objects show that objects are recognized in multiple ways (e.g., a VW Beetle can be recognized as a car or a beetle) and that categorization performance is based on the visual and motor movement similarity between objects. Here, we studied whether we find evidence for multiple levels of categorization for social interactions (physical interactions with another person, e.g., handshakes). To do so, we compared visual categorization of objects and social interactions (Experiments 1 and 2) in a grouping task and assessed the usefulness of motor and visual cues (Experiments 3, 4, and 5) for object and social interaction categorization. Additionally, we measured recognition performance associated with recognizing objects and social interactions at different categorization levels (Experiment 6). We found that basic level object categories were associated with a clear recognition advantage compared to subordinate recognition but basic level social interaction categories provided only a little recognition advantage. Moreover, basic level object categories were more strongly associated with similar visual and motor cues than basic level social interaction categories. The results suggest that cognitive categories underlying the recognition of objects and social interactions are associated with different performances. These results are in line with the idea that the same action can be associated with several action interpretations (e.g., a person waving his arm can be recognized as waving or greeting).  相似文献   
155.
Categorization of seen objects is often determined by the shapes of objects. However, shape is not exclusive to the visual modality: The haptic system also is expert at identifying shapes. Hence, an important question for understanding shape processing is whether humans store separate modality-dependent shape representations, or whether information is integrated into one multisensory representation. To answer this question, we created a metric space of computer-generated novel objects varying in shape. These objects were then printed using a 3-D printer, to generate tangible stimuli. In a categorization experiment, participants first explored the objects visually and haptically. We found that both modalities led to highly similar categorization behavior. Next, participants were trained either visually or haptically on shape categories within the metric space. As expected, visual training increased visual performance, and haptic training increased haptic performance. Importantly, however, we found that visual training also improved haptic performance, and vice versa. Two additional experiments showed that the location of the categorical boundary in the metric space also transferred across modalities, as did heightened discriminability of objects adjacent to the boundary. This observed transfer of metric category knowledge across modalities indicates that visual and haptic forms of shape information are integrated into a shared multisensory representation.  相似文献   
156.
Ongoing professional development for practicing genetic counselors is critical in maintaining best practice. Communication skills training (CST) workshops for doctors in oncology, utilizing trained actors in role plays, have been implemented for many years to improve patient-centred communication. This model was adapted to provide professional development in counseling skills for practicing genetic counselors, already highly trained in counseling skills. Detailed evidence based scenarios were developed. Evaluation of participants’ experience and perceived outcomes on practice included surveys immediately post workshops (2002, 2004, 2005, 2008 (×2); n = 88/97), 2–5 years later (2007; n = 21/38) and a focus group (2007; n = 7). All rated workshops as effective training. Aspects highly valued included facilitator feedback, actors rather than role-playing with peers and being able to stop and try doing things differently. Perceived outcomes included the opportunity to reflect on practice; bring focus to communication; motivation and confidence. The high level of satisfaction is a strong endorsement for ongoing communication skills training in this format as part of professional development.  相似文献   
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