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971.
972.
The authors report a study that suggests the career paths of workers on short-term federal projects may be enhanced as a result of developing a relationship with a mentor through such projects.  相似文献   
973.
Because rheumatoid arthritis (RA) has a more unpredictable course than osteoarthritis (OA), we hypothesized that generalized expectancies (optimistic/ pessimistic) influence the psychosocial adjustment of RA patients, whereas disease severity influences the adjustment of OA patients. Path analysis (LISREL VI) revealed that pessimistic RA patients (N= 107) and the more physically disabled OA patients (N= 108) reported poorer adjustment. The hypothesized mediating role of coping was supported for the RA but not the OA sample; that is, pessimism was associated with poor adjustment through greater use of wishful thinking coping. Unexpectedly, problem-solving coping was not found to mediate the optimism adjustment relationship.  相似文献   
974.
There is growing evidence to suggest that the ways in which people think about their health problems may have significant implications for psychological and physical well-being. This possibility has the greatest consequences for those groups facing health problems on a daily basis, in particular, the elderly. This study examined the role of perceived health barriers and value for health in later life. A Perceived Health Barriers (absent, present) by Health Value (low, medium, high) 2.3 factorial design was analyzed for younger and older seniors on: number of life-threatening diseases, need for health care, and life satisfaction. In addition, a longitudinal design was used to examine the joint roles of perceived health barriers (PHBs) and health value (HV) on mortality. Findings generally indicated that individuals’ PHBs and HV are associated with health-related outcomes; however, the results differed for young and old elders. Among young elders, those with PHBs and those with high HV had the most negati e profile. That is, they had more diseases, higher health care needs, and lower life satisfaction. Among older elders, the findings were more complicated in that the relationship between PHB and the outcomes depended on HV. Overall, the patterns for old elders suggest that perceived health barriers are most relevant among those with medium value for health and least relevant among those with low value for health.  相似文献   
975.
Three mildly malnourished children with cystic fibrosis and their parents participated in a behavioral group-treatment program that focused on promoting and maintaining increased calorie consumption. Treatment included nutritional education, gradually increasing calorie goals, contingency management, and relaxation training, and was evaluated in a multiple baseline design across four meals. Children's calorie intake increased across meals, and total calorie intake was 32% to 60% above baseline at posttreatment. Increased calorie consumption was maintained at the 96-week follow-up (2 years posttreatment). The children's growth rates in weight and height were greater during the 2 years following treatment than the year prior to treatment. Increases in pace of eating and calories consumed per minute were also observed 1 year posttreatment. These findings replicated and extended earlier research supporting the efficacy of behavioral intervention in the treatment of malnutrition in children with cystic fibrosis.  相似文献   
976.
977.
Violations of strong stochastic transitivity in concurrent-chains choice were first reported by Navarick and Fantino. In a series of articles, Navarick and Fantino concluded that neither a unidimensional model capable of predicting exact choice probabilities nor a fixed-variable equivalence rule was possible for the concurrent-chains procedure. I show that when choice is modeled contextually (i.e., when preference for a schedule is affected by factors other than the schedule itself, e.g., aspects of the alternative schedule), a unidimensional, exact-choice probability model is possible that both predicts the intransitivities reported by Navarick and Fantino and provides a fixed-variable equivalence rule for the concurrent-chains procedure. The contextual model is an extension of the generalized matching law and violates a key assumption underlying traditional choice models—simple scalability—because of (a) schedule interdependence and (b) bias from procedural contingencies. Therefore, strong stochastic transitivity cannot be expected to hold. Contextual scalability is analyzed to reveal a hierarchy of context effects in choice. Navarick and Fantino's intransitivities can be satisfactorily explained by bias. If attribute sensitivity is context dependent, however, and if there are similarity structures among choice alternatives, the contextual model is shown to be able to predict violations of ordinal preference. Therefore, it may be possible to formulate a deterministic, general psychophysical model of choice as a behavioral alternative to probabilistic, multidimensional choice theories.  相似文献   
978.
Eight pigeons were trained on concurrent variable-interval variable-interval schedules with a minimum interchangeover time programmed as a consequence of changeovers. In Experiment 1 the reinforcement schedules remained constant while the minimum interchangeover time varied from 0 to 200 s. Relative response rates and relative time deviated from relative reinforcement rates toward indifference with long minimum interchangeover times. In Experiment 2 different reinforcement ratios were scheduled in successive experimental conditions with the minimum interchangeover time constant at 0, 2, 10, or 120 s. The exponent of the generalized matching equation was close to 1.0 when the minimum interchangeover time was 0 s (the typical procedure for concurrent schedules without a changeover delay) and decreased as that duration was increased. The data support the momentary maximizing theory and contradict molar maximizing theories and the melioration theory.  相似文献   
979.
Studied 194 lesbian, gay, and bisexual youth aged 21 and younger who attended programs in 14 community centers to determine the personal challenges they face due to their sexual orientation and their responses to these stresses. First awareness of sexual orientation typically occurred at age 10, but disclosure to another person did not occur until about age 16. There was much variability in sexual behavior, and many youths reported both same-sex and opposite-sex sexual experiences. Although most had told at least one family member about their sexual orientation, there remained much concern about family reactions. Suicide attempts were acknowledged by 42% of the sample. Attempters significantly differed from nonattempters on several milestones of sexual orientation development, social aspects of sexual orientation, parents' knowledge of sexual orientation, and mental health problems. The following organizations participated in this project and are thanked for their assistance: Affirmations (Detroit), the Atlanta Gay Center, Baltimore Gay and Lesbian Community Center, Boston Alliance of Gay and Lesbian Youth, Gay Alternative Youth (Pittsburgh), the Gay and Lesbian Youth Association of Dallas, Gay Youth Alliance — San Diego, the Gay and Lesbian Community Services Center of Los Angeles, Horizons Community Services (Chicago), the Indianapolis Youth Group, the Lesbian and Gay Community Services Center of Cleveland, Lavender Youth Recreation and Information Center (San Francisco), Outright (Denver), and Sexual Minority Youth Assistance League (Washington, DC). The following individuals associated with these groups are gratefully thanked for their help: Danny Barutta, Adriene Corbin, Tom Eversole, Chris Gonzalez, Bill Gripp, Rory Lopez, Phil Rector, Jamie Schield, Cheryl Schwartz, Jan Stephenson, Sterling Stowell, Amy Vitro, and Aubrey Wertheim. Gene Thomas is thanked for helping with data collection, as are Michael LaFlam, Patrick McNamara, and Mark Shiner, who processed the surveys. We also thank Rainer Silbereisen for his comments. This project was supported by funds from the Center for the Study of Child and Adolescent Development of the College of Health and Human Development at Pennsylvania State University.  相似文献   
980.
The purpose of this research was to determine the role of syllabic stress in language processing during the early on-line processing of speech and later in the representation of a sentence in memory. Experiment 1 used a syllable monitoring task while Experiment 3 used a probe task in which subjects heard a sentence and then were asked to determine whether a probe syllable had occurred in the sentence. In the monitoring task, stressed syllables were detected more rapidly in word-initial position, but unstressed syllables were detected more rapidly in word-final position. Stress facilitation in initial syllables was strongly related to high relative F0, but not to changes in perceived vowel quality as assessed in Experiment 2. This pattern is interpreted as evidence that lexical stress is used on-line to guide lexical access and/or lexical segmentation. The probe task of Experiment 3 showed stress facilitation in both positions, indicating that stress is independently retained in the postperceptual representation of a sentence.The research reported in this paper was supported by grant 80-0416 to Harvard University (Peter C. Gordon, Principal Investigator) from the Air Force Office of Scientific Research Life Sciences Directorate. We thank Chris Thurber for his extensive and competent assistance in testing subjects and making acoustic measurements, and Jay Rueckl for comments on an earlier version of this paper  相似文献   
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