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   60168篇
  免费   2329篇
  国内免费   23篇
  62520篇
  2019年   618篇
  2018年   876篇
  2017年   901篇
  2016年   979篇
  2015年   735篇
  2014年   850篇
  2013年   4269篇
  2012年   1611篇
  2011年   1645篇
  2010年   1068篇
  2009年   998篇
  2008年   1514篇
  2007年   1454篇
  2006年   1309篇
  2005年   1200篇
  2004年   1145篇
  2003年   1105篇
  2002年   1139篇
  2001年   1780篇
  2000年   1744篇
  1999年   1304篇
  1998年   631篇
  1997年   592篇
  1996年   582篇
  1992年   1241篇
  1991年   1176篇
  1990年   1173篇
  1989年   1047篇
  1988年   1049篇
  1987年   1013篇
  1986年   1070篇
  1985年   1135篇
  1984年   903篇
  1983年   808篇
  1982年   576篇
  1981年   583篇
  1979年   1009篇
  1978年   712篇
  1977年   658篇
  1976年   660篇
  1975年   866篇
  1974年   1034篇
  1973年   1097篇
  1972年   893篇
  1971年   876篇
  1970年   827篇
  1969年   851篇
  1968年   1107篇
  1967年   982篇
  1966年   932篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
871.
A design for an Apple II interface that senses relative rotary position and/or motion via a digital potentiometer is presented. A thorough discussion of the circuit’s theory of operation and a fully commented BASIC software listing are included. Suggested applications include an infinite-turn rotary device for psychophysical methods of adjustment, the sensing of rotary translations of a steering wheel in a driving simulator, and a digital tachometer/odometer for tracking performance on stationary exercise bicycles and treadmills.  相似文献   
872.
Normative data are presented for the probability of successfully completing 192 single-solution word fragments. Normative data on the familiarity of college students with the solution words are also given, along with estimates of word frequency from existing norms. Regression analyses were performed in order to predict fragment completion difficulty from familiarity, frequency, and several structural characteristics of the fragments. Familiarity, whether or not first and/or last letters appeared in the fragment, and the ratio of letters to missing letters in the fragment were included in the regression equation as significant predictors of difficulty for this fragment set.  相似文献   
873.
A suite of programs is described for simulating the Rescorla-Wagner (1972) model of associative learning, the Solomon and Corbit (1974) opponent-process theory, and Schull’s (1979) extension of the latter. The programs are written for the Commodore 64 computer.  相似文献   
874.
W E Thompson  R A Dodder 《Adolescence》1986,21(82):365-376
All seven variables of containment theory were operationalized for questionnaires. Data were collected from 677 adolescents in a variety of high schools and correctional institutions, and divided into categories by race and sex. Factor analysis indicated that the structure of the relationships among the seven containment variables and delinquency was substantially different among black females.  相似文献   
875.
W M Nelson  S N Cholera 《Adolescence》1986,21(84):855-862
The purpose of this study is to examine the interrelationships among coping statements, a self-report measure of anxiety and maladaptive overt behavior in a real-life stressful situation. Measures of these variables (interviews using TAT-like cards, State-Trait Anxiety Inventory for Children, Behavior Profile Rating Scale) were taken from 23 adolescents prior to and during their dental visit. Results indicated that as disruptive "in-chair" overt behavior increased, so did the percentage of coping statements. In addition, as self-report levels of anxiety increased, the percentage of coping statements significantly decreased. Interestingly, there was no significant relationship between self-report levels of anxiety and disruptive in-chair behavior. It was also noted that the subjects' self-report levels of anxiety significantly decreased following their opportunity to verbalize their coping/noncoping statements via the TAT-like procedure. The implications of these interrelationships to cognitive-behavioral theory are discussed.  相似文献   
876.
W E Hauck  M Martens  M Wetzel 《Adolescence》1986,21(83):529-534
The imaginary audience of 328 early and late adolescents was studied from the viewpoint of providing educators and clinicians with insight into its attributes--those which both facilitate and hinder youths' development. Early adolescents (about 14 or 15 years of age) displayed a greater awareness of an imaginary audience which probably contributed to their observed, elevated group dependence. Unexpectedly, the shyness of adolescents highly sensitive to an imaginary audience increased with age, possibly because they are unwilling to provide themselves with the social experiences necessary for decentering. Likewise, those highly sensitive to an imaginary audience projected low self-concepts and thus imply that their audience is relatively critical; thus, they probably validate a self-fulfilling prophecy, oblivious to a possible contradictory external reality. The anticipated fact that females appeared to be less socially bold and more group dependent than males might account, in part, for females' greater responsiveness to an imaginary audience. It is suggested that educators and clinicians encourage youth to validate social hypotheses in order to promote the dissolution of the imaginary audience, especially of those who are shy and display self-deprecatory tendencies.  相似文献   
877.
This study measured students' attitudes toward a university's student health services (SHS) and identified factors that were related to their attitudes. A questionnaire surveying students' attitudes was administered to a sample of 150 students at the Oxford Campus of the University of Mississippi. Analysis of the data revealed that students' attitudes had a statistically significant correlation with the following variables: perceived medical care cost, amount of health information/education received during medical encounters, time spent in the waiting room of the SHS, sex of the student, and income of the student. There was no significant relationship between attitude and age.  相似文献   
878.
R L Calabrese  H Schumer 《Adolescence》1986,21(83):675-687
This research evaluated the effects of involvement of adolescents in community service activities on levels of alienation. It was proposed that alienation could be reduced through the implementation of a model which utilized community service activities to facilitate adolescent access to adult society, development of responsibility, collaborative and cooperative work, and control over planning and outcomes. It is suggested that adolescent involvement in service activities can produce positive benefits, among which are reduced levels of alienation, improved school behavior, improved grade point average, and acceptance by the adult community. These findings also suggest that females respond more positively to school when allowed to problem-solve collectively and collaboratively.  相似文献   
879.
Health needs and concerns of male adolescents   总被引:1,自引:0,他引:1  
W J Pinch  M Heck  D Vinal 《Adolescence》1986,21(84):961-969
Lifestyle factors established within the family help determine health-care functioning. Adolescents first may be challenged to meet their own health needs as freshmen in college. A 153-item questionnaire was utilized to examine concerns in the areas of alcohol and other drug use, auto safety, weight and dieting, smoking, sexuality, coping and stress, and selection and utilization of health-care services. One hundred fifty-nine male college students responded. Major problems with alcohol use, auto safety, weight control, stress and sexuality were identified. Positive lifestyle factors that were strongly supported included regular exercise, nonsmoking, regular medical and dental checkups, and the development of some support systems to cope with stress. Health-care services designated by respondents to meet their own needs were significantly different from those services they pointed out as needed for their peers.  相似文献   
880.
Modifications and adjuncts to traditional therapy techniques appear to be necessary for successfully treating hospitalized adolescents with impaired social and verbal skills, and a history of acting-out behavior. Modified therapy groups were combined with a structured biofeedback and cognitive training program to help these adolescents control anger and modify their behavior. Used in conjunction with training and practice in relaxation techniques, this multimodal treatment approach appeared to be helpful in both reducing incidents of acting out on residential units, and in reaching individualized therapeutic goals. The present paper describes use of this multimodal approach within selected residential settings, and outlines the structured materials developed by the authors.  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