首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   21780篇
  免费   848篇
  国内免费   11篇
  2019年   254篇
  2018年   368篇
  2017年   390篇
  2016年   411篇
  2015年   317篇
  2014年   348篇
  2013年   1735篇
  2012年   621篇
  2011年   640篇
  2010年   385篇
  2009年   364篇
  2008年   490篇
  2007年   544篇
  2006年   463篇
  2005年   441篇
  2004年   414篇
  2003年   406篇
  2002年   435篇
  2001年   742篇
  2000年   710篇
  1999年   537篇
  1998年   214篇
  1996年   221篇
  1995年   197篇
  1992年   448篇
  1991年   440篇
  1990年   425篇
  1989年   400篇
  1988年   418篇
  1987年   375篇
  1986年   388篇
  1985年   386篇
  1984年   306篇
  1983年   274篇
  1982年   203篇
  1981年   206篇
  1979年   349篇
  1978年   253篇
  1977年   213篇
  1976年   198篇
  1975年   279篇
  1974年   354篇
  1973年   367篇
  1972年   288篇
  1971年   282篇
  1970年   281篇
  1969年   251篇
  1968年   349篇
  1967年   307篇
  1966年   284篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Three experiments were conducted to examine the relation between response tempo and separable-integral responding. A restricted classification paradigm, in which similarity-based (integral) and dimensionally based (separable) classifications were pitted against one another, was used with the dimensions of length and density (all experiments) and size and brightness (Experiment 3). The subjects were college students (Experiments 1 and 2) and kindergarten, second-, and fifth-grade children (Experiment 3). In all three experiments, rapid responding was associated with fewer dimensional and more similarity responses than was slow responding. This result held when response tempo was simply measured (Experiments 1 and 3) and when it was manipulated by the experimenter (Experiment 2). The results were interpreted to be consistent with models of dimensional processing in which holistic, integral processing precedes analytic dimensional processing.  相似文献   
993.
Several studies of metacontrast masking in the 1960s apparently showed that the latency of simple detection responses was uninfluenced by the phenomenal dimming of the target induced by the mask. More recent studies using more suitable methodologies have clearly shown that such is not the case for situations in which the masking is a monotonically decreasing function of stimulus onset asynchrony. Experiment 1 investigated this issue for the situation in which masking is a U-shaped function of stimulus onset asynchrony. Contrary to the results obtained in monotonic masking situations, simple detection responses were not slowed by the masking. Experiment 2 demonstrated that although detection responses are not slowed in the U-shaped masking situation, spatial-choice judgments are. Experiments 3 and 4 indicated that this masking effect on spatial-choice reaction time is lost relatively rapidly with practice. However, changing the stimulus-response assignments reinstates the effect. The experiments suggest that for the situation in which U-shaped masking functions are obtained, responses that require attention (spatial-choice judgments early in practice or after stimulus-response relationships have been switched) are influenced by the metacontrast-induced phenomenal dimming, whereas responses that are automatic (i.e., detection responses; practiced spatial-choice judgments with consistent stimulus-response mappings) are not.  相似文献   
994.
Impaired retention of an inhibitory avoidance response was observed in rats subjected to adrenalectomy (ADX) up to 120 hr before the single learning trial. Corticosterone substitution failed to normalize this behavioral deficit. Rats ADX 240 hr prior to the learning trial showed a normalized behavior. Adrenomedullectomy (ADXM) 48 or 240 hr before learning caused a similar impairment as in short-term ADX rats. The 240-hr ADX rats subjected to corticosterone substitution showed the same behavioral deficit as short-term ADX rats or ADXM ones. Immediate postlearning subcutaneous injection of adrenaline in a dose range of 0.005-5.0 micrograms/kg or of noradrenaline (0.005-0.5 microgram/kg) to 48-hr ADX rats resulted in a dose-related improvement of later retention behavior. Higher doses of catecholamines were less or ineffective. Postlearning treatment of 48-hr ADXM rats with adrenaline (0.5-500 micrograms/kg) caused a similar pattern of behavioral changes. It is concluded that adrenal catecholamines play an important role in the modulation of consolidation of memory. In addition, the high circulating ACTH levels that follow long-term ADX may correct for the behaviorial deficit induced by the absence of adrenomedullary catecholamines.  相似文献   
995.
A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups.  相似文献   
996.
S Whittaker  B H Bry 《Adolescence》1991,26(104):865-876
When adolescents behave in socially unacceptable ways, overt interparental conflict is widely held to be the cause. Empirical studies, however, have been inconsistent in supporting this assumption. Some researchers therefore have speculated that covert conflict also plays a role. In the current observational study, evidence was found that both overt parental conflict and some forms of covert conflict play roles. During problem-solving family discussions, parents of adolescents whom they had brought into an outpatient clinic for treatment overtly disagreed with each other significantly more often than did parents with adolescents who did not require treatment. Families of clinic adolescents also exhibited significantly more silence during their discussions, and mothers spent significantly less time talking than did their nonclinic counterparts. The implications that both the overt and covert conflict may have for adolescent behavior are discussed.  相似文献   
997.
It is argued that the design of contemporary psychotherapy outcome studies is conceptually incompatible with the models of psychotherapy evaluated in those studies. Contemporary outcome studies are incompatible with psychotherapy models because the outcome studies treat patients with standardized treatments that are assigned on the basis of psychiatric diagnosis rather than with individualized treatments based on a theory-driven psychological assessment of the individual's difficulties. One possible remedy, idiographic outcome studies using a case formulation model of assessment and treatment, is proposed here. It is suggested that this research strategy may narrow the scientist-practitioner gap and make it easier to demonstrate differential outcomes of different treatments.  相似文献   
998.
This study compares social relationships of 677 mothers in families requesting shelter with those of 495 mothers in housed families, randomly selected from the public assistance caseload in New York City. As hypothesized, women seeking shelter had experienced higher levels of a variety of childhood and adult events indicative of disruptions in social relationships. Contrary to our hypothesis, they were more likely than were housed mothers to have had recent contact with parents, other relatives, and friends, although they felt less able to draw on these resources for help with their current housing needs. More than three fourths of families seeking shelter had already stayed with members of their social network in the past year. The data suggest that they had used up potential sources of support before turning to public shelter.  相似文献   
999.
B J Mann  C M Borduin 《Adolescence》1991,26(103):505-541
Although interest in identifying effective psychotherapies for adolescent mental health problems has increased dramatically in the last decade, there have been few attempts to summarize and integrate the recent empirical literature on psychotherapy outcomes with adolescents. The present paper reviews the methods and findings of adolescent psychotherapy outcome studies published from 1978 to 1988. Evaluations of individual psychotherapy with adolescents generally reveal positive short-term outcomes, but long-term outcomes are still to be determined. Evaluations of systemic therapies (especially family therapy) with adolescents often reveal positive outcomes that are maintained over extended follow-up periods. Recommendations are presented for improving the methodology of future psychotherapy outcome studies with adolescents.  相似文献   
1000.
N B Farber 《Adolescence》1991,26(103):697-716
This paper reports on in-depth interviews with black and white unmarried adolescent mothers, from a variety of socioeconomic backgrounds, about their pregnancy resolution. They revealed the importance of family members and other significant adults in the decision process. The analysis also indicated that personal, familial, and religious values were primary considerations in deciding to bear and keep their children.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号