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31.
Infants experienced a female adult handing them toys. Sometimes, however, the transaction failed, either because the adult was in various ways unwilling to give the toy (e.g., she teased the child with it or played with it herself) or else because she was unable to give it (e.g., she accidentally dropped it). Infants at 9, 12, and 18 months of age reacted with more impatience (e.g., reaching, looking away) when the adult was unwilling to give them the toy than when she was simply unable to give it. Six-month-olds, in contrast, showed no evidence of this differentiation. Because infants' behavioral responses were appropriately adapted to different kinds of intentional actions, and because the adult's actions sometimes produced results that did not match her goal (when having accidents or failed attempts), these findings provide especially rich evidence that infants first begin to understand goal-directed action at around 9 months of age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Infants at 12 and 18 months of age played with 2 adults and 2 new toys. For a 3rd toy, however, 1 of the adults left the room while the child and the other adult played with it. This adult then returned, looked at all 3 toys aligned on a tray, showed great excitement ("Wow! Cool!"), and then asked, "Can you give it to me?" To retrieve the toy the adult wanted, infants had to (a) know that people attend to and get excited about new things and (b) identify what was new for the adult even though it was not new for them. Infants at both ages did this successfully, lending support to the hypothesis that 1-year-old infants possess a genuine understanding of other persons as intentional and attentional agents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
The Authors discuss etiology, clinical picture, diagnostic and therapeutic possibilities of intestinal volvulus, an uncommon disease in Europe, thinking of a case of primitive small intestine volvulus, recently observed, and considering the literature. The Authors have come to the conclusion that in all the cases of intestinal occlusion, in emergency hospitalization, it is important to suspect the intestinal volvulus and to operate on the patient urgently to avoid the raise of postoperative mortality in all the cases complicated with intestinal gangrene.  相似文献   
35.
Twelve domestic dogs (Canis familiaris) were given a series of trials in which they were forbidden to take a piece of visible food. In some trials, the human continued to look at the dog throughout the trial (control condition), whereas in others, the human (a) left the room, (b) turned her back, (c) engaged in a distracting activity, or (d) closed her eyes. Dogs behaved in clearly different ways in most of the conditions in which the human did not watch them compared with the control condition, in which she did. In particular, when the human looked at them, dogs retrieved less food, approached it in a more indirect way, and sat (as opposed to laid down) more often than in the other conditions. Results are discussed in terms of domestic dogs' social-cognitive skills and their unique evolutionary and ontogenetic histories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
Two studies investigating the linguistic representations underlying English-speaking 2 1/2-year-olds' production of transitive utterances are reported. The first study was a training study in which half the children heard utterances with full nouns as agent and patient, and half the children heard utterances with both pronouns (i.e., He's [verb]-ing it) and also full nouns. In subsequent testing, only children who had been trained with pronouns and nouns were able to produce a transitive utterance creatively with a nonce verb. The second study reported an analogous set of findings, but in comprehension. Together, the results of these 2 studies suggest that English-speaking children build many of their early linguistic constructions around certain specific lexical or morphological items and patterns, perhaps especially around particular pronoun configurations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This article deals with looking for the best passive samplers among eleven plants diffused in the Mediterranean basin for the determination of polycyclic aromatic hydrocarbons in the atmosphere in substitution to the particulate matter sampling. The most recent research about biological passive samplers showed a quali-quantitative difference in pollutant sampling by different plants. Evergreen trees with long-lived leaves were selected in the urban area of Catania (Italy) and both samples (leaves and particulate matter) were extracted and purified by a two stage method before the analysis was performed by a GC/MS. Leaves and particulate matter were sampled in three different seasons (winter, spring and summer). PAHs concentrations found in the particulate matter and leaves were correlated. Some plants ( Olea europaea and Quercus ilex ) showed high values (r 2 > 0.85) of linear correlation coefficient in all seasons and are characterized by profiles similar to that of the particulate matter. Further, it has been observed that during the warmer seasons the total quantity of PAH adsorbed by the plants is greater but the fitting is better during winter. No difference was found by washing leaves with distilled water: this means that PAHs aren't deposited on the surface but are adsorbed in the lipidic layer of the leaves.  相似文献   
39.
We report 3 studies of the referential pointing of 2 orangutans (Pongo pygmaeus). Chantek was raised in an enculturated environment; Puti, raised in a nursery, had a more typical captive life. In Experiment 1, flexibility of pointing behavior was investigated by requiring subjects to point in novel circumstances (for an out-of-sight tool, not food). In Experiment 2, we investigated the orangutans' comprehension of the significance of a human point in helping them to locate food. In Experiment 3, we investigated whether these pointing subjects comprehended that a human recipient must be looking for the point to achieve its attention-directing goal. In all experiments the enculturated orangutan showed better understanding of pointing than the captive orangutan. This finding is consistent with recent studies that have found differences in the cognitive and social-cognitive abilities of apes that have had different types of experience with humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
At around 1 year of age, human infants display a number of new behaviors that seem to indicate a newly emerging understanding of other persons as intentional beings whose attention to outside objects may be shared, followed into, and directed in various ways. These behaviors have mostly been studied separately. In the current study, we investigated the most important of these behaviors together as they emerged in a single group of 24 infants between 9 and 15 months of age. At each of seven monthly visits, we measured joint attentional engagement, gaze and point following, imitation of two different kinds of actions on objects, imperative and declarative gestures, and comprehension and production of language. We also measured several nonsocial-cognitive skills as a point of comparison. We report two studies. The focus of the first study was the initial emergence of infants' social-cognitive skills and how these skills are related to one another developmentally. We found a reliable pattern of emergence: Infants progressed from sharing to following to directing others' attention and behavior. The nonsocial skills did not emerge predictably in this developmental sequence. Furthermore, correlational analyses showed that the ages of emergence of all pairs of the social-cognitive skills or their components were inter-related. The focus of the second study was the social interaction of infants and their mothers, especially with regard to their skills of joint attentional engagement (including mothers' use of language to follow into or direct infants' attention) and how these skills related to infants' early communicative competence. Our measures of communicative competence included not only language production, as in previous studies, but also language comprehension and gesture production. It was found that two measures--the amount of time infants spent in joint engagement with their mothers and the degree to which mothers used language that followed into their infant's focus of attention--predicted infants' earliest skills of gestural and linguistic communication. Results of the two studies are discussed in terms of their implications for theories of social-cognitive development, for theories of language development, and for theories of the process by means of which human children become fully participating members of the cultural activities and processes into which they are born.  相似文献   
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