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971.
Measures of illusion magnitude for a real-contour and two subjective-contour Poggendorff figures were obtained from 42 men and 42 women. Although magnitudes of illusion differed as a function of figure type, male-female differences in magnitude of illusion did not vary across figures or judgment orders. Also, correlations among the illusions observed for three types of figures did not differ for men and women. These data are consistent with the view that real- and subjective-contour Poggendorff figures evoke similar processing strategies and that sex differences, when observed, are probably the result of differences in cognitive-judgmental strategy rather than differences in the optical and neural properties of the visual system.  相似文献   
972.
Traditional Dental Aptitude Test and academic grade point average have been shown to be poor predictors of clinical performance by dental students. To refine predictors of psychomotor skills, a wire-bending test was given to 105 freshmen at the beginning of their dental education. Grades from seven restorative preclinical courses in their freshman and sophomore years were compared to scores on wire bending and the three traditional predictors: GPA, academic aptitude, and perceptual aptitude scores. Wire-bending scores correlated significantly with six out of seven preclinical restorative courses. The predictive power for preclinical performance was doubled when wire bending was added to traditional predictors in stepwise multiple regression analysis. Wire-bending scores identified students of low performance. These preliminary results suggest that the wire-bending test shows some potential as a screening test for identifying students who may hae psychomotor difficulties, early in their dental education.  相似文献   
973.
This study is a systematic replication of the effects of insulin doses on operant behavior reinforced (in an earlier study) by fixed-ratio schedules of microwave (MW) reinforcement. In this study, insulin and dextrose doses were administered (ip) prior to fixed-interval 2-min. schedules of MW reinforcement in rats tested in a cold environment. Six Sprague-Dawley rats were conditioned to regulate their thermal environment with 5-sec. exposures of MW radiation (SAR = 0.34 Watts/kg/(mW/cm2) under the FI-2' schedules. Humulin-regular insulin and 50% solutions of dextrose were administered (ip) alternately with saline control sessions for 8-hr. durations. A within-subjects, repeated-measures 4 x 8 x 3 factorial analysis of variance design showed that insulin doses suppressed operant responding for heat, which confirmed the results of the earlier study under a different schedule. In addition, high doses of dextrose had similar suppressing effects on operant responding for heat. The data are interpreted in terms of the discriminative properties of increased thermogenesis produced by the insulin and dextrose doses. The suppressing effects were more pronounced for the first two hours, yet they persisted for approximately six hours of the 8-hr. sessions.  相似文献   
974.
RELIABILITY AND VALIDITY OF IN-BASKET PERFORMANCE MEASURES   总被引:2,自引:0,他引:2  
The in-basket test is a frequently used assessment tool for predicting job performance and, to a lesser extent, as a technique for research and development in various human resource applications. While the in-basket test has obvious attractive features for application in the business setting, there is a great degree of uniqueness in each application and relatively little research focusing on critical issues involved in construction or evaluation. In this paper, the literature focusing on the psychometric properties of in-basket measures of performance are reviewed and evaluated. The compiled evidence provides only modest support of the usefulness of the in-basket test as a measurement tool.  相似文献   
975.
For purposes of selection and classification there are two general reasons for scaling the mean and variance of the utility of performance across jobs. First, if differential utility across jobs does exist, then the payoff from a selection and classification system will be enhanced to the extent that accurate utility values are incorporated in the assignment system. Second, a valid utility metric would permit a more meaningful comparison of the gains achieved by alternative selection and classification procedures. It is argued in this paper that the Army context, and perhaps others, precludes using the dollar metric and estimates of SDy in dollars. Consequently, Project A conducted a relatively long series of exploratory workshops with Army personnel to (a) define the utility issue, (b) pilot test a wide variety of possible scaling methods, and (c) evaluate the methods that seemed most appropriate. On the basis of exploratory analysis, a combined procedure incorporating both an interval estimation and a ratio estimation method was used to estimate the utility of five different performance levels for each of 276 jobs (MOS) in the enlisted personnel system. The psychometric properties of the resulting scale values are analyzed and discussed.  相似文献   
976.
MODELING JOB PERFORMANCE IN A POPULATION OF JOBS   总被引:9,自引:0,他引:9  
The Army Selection and Classification Project has produced a comprehensive examination of job performance in 19 entry-level Army jobs (Military Occupational Specialties) sampled from the existing population of entry-level positions. Multiple methods of job analysis and criterion measurement were utilized in a subsample of nine jobs to generate over 200 performance indicators, which were then used to assess performance in a combined sample of 9,430 job incumbents. An iterative procedure involving a series of content analyses and principal components analyses was used to develop a basic array of up to 32 criterion scores for each job. This basic set of scores formed the starting point of an attempt to model the latent structure of performance in this population of jobs. After alternative models were proposed for the latent structure, the models were submitted to a goodness-of-fit test via LIS-REL VI. After accounting for two components of method variance, a five-factor solution was judged as the best fit. The implications of the results and the modeling procedure for future personnel research are discussed.  相似文献   
977.
Two studies examined the speed with which good spellers and poor spellers spell easy and difficult words. At both the elementary school (Grades 3 and 4) and undergraduate levels, good spellers spelled words more quickly than poor spellers. This difference appeared even for very easy words that all subjects could spell. Implications for the importance of automaticity in spelling competence are discussed.  相似文献   
978.
Behavior at 10 and 13 years of age for children with low birth weight   总被引:1,自引:0,他引:1  
This study was based on data from a longitudinal research program. The cohort consisted of 874 normal children in an entire school grade in a Swedish community. The aim of the study was to investigate the relation between birth weight and behavior at school, for all children and for each sex separately. The results identified specific aspects of behaviour disorder significantly related to low birth weight (LBW) for children at the age of 10 but not at the age of 13. When the sexes were separated, there were no relations between birth weight and deviant behaviour for boys of low birth weight as compared to boys of normal birth weight, while girls of low birth weight showed specific behavioural disorders at age 10 as compared to girls of normal birth weight. For girls reared in families of low parental socioeconomic status, aggressiveness and motor restlessness at age 10 but not at age 13 was also present. Further analyses showed that girls born small-for-gestational age showed lack of school motivation and concentration difficulties both at age 10 and age 13.  相似文献   
979.
A group of 107 children with vascular diseases of the nervous system aged 3-14 years have been studied. In 100 children of the study group acute disturbances of the brain blood circulation have been found, out of which 37 children were with transitory ischemic attacks; 29 were found to be with brain ischaemia; 22-with haemorrhages (7 cases with subarchnoidal, 9 cases with intracerebral and 6 cases with subarachnoidal-parenchimatose); 5 children had wenous thromboses; 7 children were with spinal strokes. In other 7 children we found the presence of Sturge-Weber syndrome. Congenital vascular malformations have been found in 32 children (30%), out of which 16 children (15%) with loops and stenosis of the extracranial segments of the internal carotid artery, and another 16 children (15%) with AV-malformations. Congenital and acquired heart diseases are found to be primary cause for the strokes in 12 children (11%). Considerable is the rate of the epileptic seizures in the acute stage of the strokes as well as of the residual epileptic syndromes.  相似文献   
980.
In forensic psychology, recommendations that courts request when granting one of the parents the right of child upbringing after a divorce pose a problem for the person who is required to give such expert judgment. The authors describe the difficult situation he faces when having to decide for and, at the same time, against one of the parents. A good knowledge of family psychology and pathopsychology is essential, and for drawing up the expertise and stating his reasons, the expert requires methodical resources. The authors describe four procedures of relational diagnosis and recommend the combined use of these in conjunction with methods that have been employed so far.  相似文献   
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