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   33861篇
  免费   1375篇
  国内免费   8篇
  35244篇
  2020年   332篇
  2019年   455篇
  2018年   589篇
  2017年   635篇
  2016年   617篇
  2015年   445篇
  2014年   562篇
  2013年   2530篇
  2012年   1029篇
  2011年   1096篇
  2010年   646篇
  2009年   635篇
  2008年   936篇
  2007年   912篇
  2006年   876篇
  2005年   790篇
  2004年   763篇
  2003年   696篇
  2002年   726篇
  2001年   1037篇
  2000年   954篇
  1999年   730篇
  1998年   401篇
  1997年   323篇
  1996年   319篇
  1992年   558篇
  1991年   560篇
  1990年   534篇
  1989年   554篇
  1988年   538篇
  1987年   503篇
  1986年   529篇
  1985年   577篇
  1984年   459篇
  1983年   445篇
  1982年   369篇
  1981年   346篇
  1979年   533篇
  1978年   388篇
  1976年   369篇
  1975年   438篇
  1974年   487篇
  1973年   508篇
  1972年   408篇
  1971年   382篇
  1970年   378篇
  1969年   411篇
  1968年   488篇
  1967年   421篇
  1966年   424篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.  相似文献   
82.
We conducted three studies that tested a "change-of-standard" perspective on the relations among context, judgment, and recall. Each study consisted of two or three sessions held a few days apart. All subjects read about the sentencing decisions of one or two target trial judges and of six nontarget trial judges who consistently gave either higher or lower sentences than the target judge(s). Each study varied both the standard that was available when subjects initially judged the sentencing decisions of a target judge and the standard available when subjects subsequently recalled those decisions. To accomplish this, we varied the context of judgment, the timing of judgment, and the overall category norm for trial judges' sentencing decisions that was available at recall. We found that although subjects had been exposed to the same target information and had initially judged it in the same way, their recall of the information was different depending on whether and how a change-of-standard had occurred between judgment and recall. Unique predictions of the change-of-standard perspective were confirmed that could not be accounted for in terms of other types of context effects on judgment and memory.  相似文献   
83.
Previous research has demonstrated that mild negative emotional imagery and unpleasant sensory stimuli lead to greater electromyographic activity over the brow muscle region than mild positive imagery and stimuli, even in the absence of significant changes in visceral and general facial EMG activity. Previous research has not addressed whether electromyographic responses over the brow region are a sensitive and specific index of emotions, however, since a multiplicity of events lead to changes in brow activity. In this research, facial electromyographic and audiovisual recordings were obtained while individuals were interviewed about themselves. Afterwards, individuals were asked to describe what they had been thinking of during specific segments of the interview marked by distinctive electromyographic responses over the brow region in the context of ongoing but stable levels of activity elsewhere in the face. The results are interpreted in terms of a continuous flow hypothesis of affect-laden information processing.  相似文献   
84.
Speech nonfluency in response to questions about the marital relationship was used to assess anxiety. Subjects were 31 husbands and 31 wives, all white, college educated, from middle- to lower-middle-class families, and ranging from 20 to 30 years of age. Three types of nonfluencies were coded: filled pauses, unfilled pauses, and repetitions. Speech-disturbance ratios were computed by dividing the sum of speech nonfluencies by the total words spoken. The results support the notion that some issues within marriage are more sensitive and/or problematic than others, and that, in an interview situation, gender interacts with question content in the production of nonfluencies.  相似文献   
85.
This study was designed to assess the accuracy of perceived levels of body fatness as indicated by 11- and 12-year-old children. Using a rating scale ranging from 1 (extremely lean) through 9 (extremely overweight), 50 males and 50 females estimated personal levels of body fatness. Using a 2 × 2 between-and-within-groups ANOVA, these estimates were compared to individual skinfold sum percentile scores derived from comparisons with national skinfold norms. The results revealed that the females tended to overestimate personal levels of body fatness, whereas estimates given by the male subjects were interpreted as not significantly different from skinfold sum percentile scores.  相似文献   
86.
Although peers' and teachers' evaluations of children's prosocial behavior and peers' sociometric ratings frequently have been used in studies of social development, the validity of young children's ratings of others has been questioned, as has that for teachers' ratings of prosocial behavior. In this study, preschoolers' ratings of peers' sociometric status and prosocial behavior, as well as teachers' ratings of children's prosocial dispositions, were obtained. These were correlated with children's naturally occurring prosocial or social behavior; ratings of prosocial behavior also were correlated with children's prosocial moral reasoning and prosocial self-attributions. Peers' sociometric ratings were positively related to children's sociability whereas prosocial ratings were related to helping (but not sharing) behavior. Teachers' ratings of prosocial behavior were not related to frequency of prosocial behaviors, but were positively related to developmentally mature moral judgments and self-reported motives.  相似文献   
87.
Tobacco, alcohol, and drug use are problems for American-Indian people. We reviewed these problems and the explanations for them and described a bicultural competence skills approach for preventing substance abuse with American-Indian adolescents. Data from a study of that approach suggest its efficacy with American-Indian youth. At posttest and a 6-month follow-up, American-Indian subjects who received preventive intervention based on bicultural competence skills concepts improved more than did American-Indian subjects in a no-intervention control condition on measures of substance-use knowledge, attitudes, and interactive skills, and on self-reported rates of tobacco, alcohol, and drug use. Our findings have implications for future substance-abuse prevention research with American-Indian people.  相似文献   
88.
The present study demonstrates the safety and effectiveness of an outpatient program designed to respond to adolescent-precipitated crises by mobilizing and restructuring the family's kinship system. Families of 75 adolescents at risk for hospitalization were followed up to 24 months after treatment with Systemic Crisis Intervention. Measures of offspring and family functioning, suicidal behavior, institutional use, and treatment costs are presented. Results clearly demonstrate the safety, effectiveness, and economic viability of Systemic Crisis Intervention.  相似文献   
89.
90.
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