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11.
Theory of mind is claimed to develop universally among humans across cultures with vastly different folk psychologies. However, in the attempt to test and confirm a claim of universality, individual studies have been limited by small sample sizes, sample specificities, and an overwhelming focus on Anglo- European children. The current meta-analysis of children's false-belief performance provides the most comprehensive examination to date of theory-of-mind development in a population of non-Western children speaking non-Indo-European languages (i.e., Mandarin and Cantonese). The meta-analysis consisted of 196 Chinese conditions (127 from mainland China and 69 from Hong Kong), representing responses from more than 3,000 children, compared with 155 similar North American conditions (83 conditions from the United States and 72 conditions from Canada). The findings show parallel developmental trajectories of false-belief understanding for children in China and North America coupled with significant differences in the timing of development across communities-children's false-belief performance varied across different locales by as much as 2 or more years. These data support the importance of both universal trajectories and specific experiential factors in the development of theory of mind. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Children's theory of mind appears to develop from a focus on desire to a focus on belief. However, it is not clear (a) whether this pattern is universal and (b) whether it could also be explained by linguistic and sociocultural factors. This study examined mental state language in 10 Mandarin-speaking (21–27 months) and 8 Cantonese-speaking (18–44 months) toddlers. The results suggest a pattern of theory-of-mind development similar to that in English, with early use of desire terms followed by other mental state references. However, the Chinese-speaking children used desire terms much earlier, and the use of terms for thinking was very infrequent, even for Mandarin-speaking adults. This finding suggests a consistency in the overall sequence, but variation in the timing of beginning and end points, in children's theory-of-mind development across cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Maze performance and morphology of frontal cortex were assessed in young adult, middle-aged, and aged rats with and without lesions of the nucleus basalis magnocellularis. Although maze performance did not vary with age, neuron number and the thickness of superficial laminae were reduced in aged rats. Lamina II-III neurons were hypertrophied in middle-aged rats relative to both younger and older groups. At all ages, lesions significantly impaired maze performance. In young adult rats, lesions moderately reduced the size of lamina II-III neurons. This effect was more pronounced in middle-aged rats. Lesions in aged rats did not affect neuron size. The neuronal changes seen in middle-aged rats may reflect a compensatory response to the expression of other age-related neuronal changes, which may affect the ability of cortical neurons to respond to lesion-induced loss of cholinergic input.  相似文献   
14.
Autonomous hypersecretion of aldosterone (primary hyperaldosteronism) is caused by either hyperplasia (usually bilateral) or an adenoma (frequently unilateral) of the adrenal cortex. Systemic hypertension due to an aldosteronoma is a potentially curable condition through surgical extirpation of the offending organ. In our experience with 37 patients clinically suspected to have primary hyperaldosteronism, radiological methods contributed significantly in preoperative diagnosis. These included (1) selective bilateral adrenal vein catheterization and blood sample collection, (2) adrenal venography, and (3) radioisotope adrenal scan. Unilateral hyperfunction could be accurately detected by the aldosterone assays from the collected samples. When adrenal venography was technically satisfactory, a nodule or aggregate of nodules measuring at least 7 mm and located on the margin of the gland or 1.5 cm or more in diameter when located in the center of the gland were readily identified. Enlarged adrenal gland on venography, in itself, was not a dependable index of a hyperfunctioning gland. Presence of a higher uptake on one side on the radioisotope adrenal scan did not always indicate the hyperfunctioning gland, but lack of lateralization of adrenal hyperfunction was more accurately predicted on the radioisotope scan than by venography. Four histopathological patterns were recognized in the surgically removed adrenal glands, but no correlation between these patterns and clinical behavior or postoperative course was found.  相似文献   
15.
Age differences in children's use of various sources of information about object location were examined in a study of search behavior in 3-, 4-, and 7-yr-olds. The 2 principal sources of information were general associative knowledge about the typical locations of objects (location specificity) and explicit verbal statements about object location. Age differences in the results reflected increasing utilization of the 2 sources of information when each was considered separately. More importantly, the design allowed consideration of Ss' ability to combine the information to limit search. In this respect, the findings reveal sophisticated information integration on the part of even the youngest Ss tested. At all ages, Ss were able to combine both sources of information when both were relevant and to ignore irrelevant location-specificity information when the verbal information was logically superordinate. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
Changes in benzodiazepine binding sites labeled by [3H]flunitrazepan (FNZ) in twenty discrete brain regions of rats made tolerant to and dependent upon pentobarbital were examined. Animals were rendered tolerant by intracerebroventricular (i.c.v.) infusion with pentobarbital (300 micrograms/ 10 microliters/ hr for six days) through pre-implanted cannulae connected to osmotic mini-pumps. The pentobarbital dependence was assessed 24 hr after abrupt withdrawal from pentobarbital. In the tolerant rats, a significant increase in [3H]FNZ binding sites was found in layer IV of frontal cortex and the molecular layer of olfactory bulb. [3H]FNZ binding sites in the pentobarbital dependent rats were significantly increased in layers I-III and V-VI of frontal cortex, caudate-putamen, olfactory tubercle, globus pallidus and ventral pallidum, in addition to those observed in the tolerant group. There was, however, no significant difference in the hippocampus and several regions in the hindbrain in either pentobarbital-treated group. Taken together with characteristics of subtypes of benzodiazepine receptors and changes in GABA-benzodiazepine receptor complexes elucidated in our previous studies, these findings suggest that both types of benzodiazepine receptors are involved in the development of pentobarbital intoxication mediated by GABAA receptors.  相似文献   
17.
The spectrum dose index (SDI) method was tested for use with data from plastic scintillator detectors by irradiating a typical portal detector system using different gamma sources and natural background. Measurements were compared with exposure rates simultaneously measured using a calibrated pressurised ion chamber. It was found that a modified SDI algorithm could be used to calculate exposure rates for these detectors despite the lack of photopeaks in plastic scintillator spectra.  相似文献   
18.
Short term patterns of early smoking acquisition   总被引:5,自引:0,他引:5  
Objective: To describe short term patterns of smoking acquisition exhibited by adolescent smokers.

Design: Interview records from the prospective development and assessment of nicotine dependence in youth study were examined retrospectively. Interviews were conducted three times per year over 30 months.

Subjects: 164 students in grades 7–9 (ages 12–15 years, 86 girls, 78 boys) who had used cigarettes at least twice.

Main outcome measures: A continuous timeline of smoking activity, beginning with the subject's first use of tobacco and continuing through follow up, was translated into six patterns—abstinent, sporadic, occasional, daily, escalating, and intermittent. Outcome measures were the proportion of subjects starting/ending in each pattern, and the number of transitions per subject between patterns.

Results: There was a general but discontinuous progression from infrequent to more frequent use, with many interspersed periods of not smoking. Escalation to daily smoking was common after the development of dependence symptoms, but was rare among those who did not have symptoms. After the appearance of symptoms, both transitions to heavier daily smoking and attempts at cessation increased.

Conclusions: Movement to heavier, more frequent smoking is generally unidirectional, although many youths attempt to quit one or more times. The appearance of any symptom of dependence altered the subsequent pattern of smoking behaviour. Future investigators might consider using more frequent data points and a continuous timeline to track smoking behaviour.

  相似文献   
19.
Our goal was to create an instrument that can be used to study how smokers lose autonomy over smoking and regain it after quitting. The Autonomy Over Smoking Scale was produced through a process involving item generation, focus-group evaluation, testing in adults to winnow items, field testing with adults and adolescents, and head-to-head comparisons with other measures. The final 12-item scale shows excellent reliability (αs = .91–.97), with a one-factor solution explaining 59% of the variance in adults and 61%–74% of the variance in adolescents. Concurrent validity was supported by associations with age of smoking initiation, lifetime use, smoking frequency, daily cigarette consumption, history of failed cessation, Hooked on Nicotine Checklist scores, and Diagnostic and Statistical Manual of Mental Disorder (4th ed., text rev.; American Psychiatric Association, 2000) nicotine dependence criteria. Potentially useful features of this new instrument include (a) it assesses tobacco withdrawal, cue-induced craving, and psychological dependence on cigarettes; (b) it measures symptom intensity; and (c) it asks about current symptoms only, so it could be administered to quitting smokers to track the resolution of symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
Fire protection in electrical control rooms can be a controversial subject, but it is an important one, especially in today's highly regulated society. The prospect of using sprinkler systems around electrical equipment can cause anxiety. Conducting a risk analysis, considering available options, selecting appropriate protection, and being prepared for emergency response will result in an optimum design and safe operation. One company's recommended practice serves as a basis for guidelines on how to choose appropriate fire protection for electrical control rooms  相似文献   
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