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The authors examined factors influencing the return rates for attempting to collect active parental consent forms from 21,123 students in the 7th through 10th grades in 41 middle and high schools. Overall return rates from middle schools were higher than from high schools. Schools that offered high levels of staff support for collecting consent forms had higher return rates. Procedures where the consent form was attached to a school form that parents had to complete and return to the school yielded the highest return rate. Implications for how researchers can obtain a high parent consent form return rate are discussed.  相似文献   
244.
To determine the extent and nature of alcohol screening and referral services provided by college health centers, the authors conducted a state-stratified, random sampling of 25% of 327 4-year accredited US colleges and universities with health centers. Of the 249 survey respondents, 32% routinely screened students for alcohol use. Urban, public, and large institutions were most likely to screen routinely. Only 11.7% of the sample reported they used standardized instruments, predominantly the CAGE. The health centers used an average of 3.4 referral options, but only 27.5% offered students access to campus programs specifically designed for students who are substance abusers. Findings suggest that the majority of college health centers are not providing routine alcohol screening for students or using standardized screening instruments. In addition, students are often referred to services that may be inappropriate or ineffective in addressing the needs of college drinkers.  相似文献   
245.
Few attempts have been made to incorporate evolutionary and cross-cultural perspectives on gambling. This paper begins with the assumption that gambling represents a risky endeavor undertaken for the purpose of winning stakes. This assumption leads to the derivation from evolutionary theory of two hypotheses concerning the socio-demographic characteristics of gamblers: (1) gambling should be over-represented among males, and (2) among young adults. To test these hypotheses, data are drawn from three sources. A cross-cultural sample of 60 societies reveals that males are more often identified as gamblers than females, and these results do not appear to reflect reporting biases. The data are insufficient to enable conclusions about age patterns associated with gambling within this cross-cultural sample. Nationally representative studies of problem and pathological gamblers drawn from seven nation states show that such gamblers tend to be over-represented by young males, as predicted. Lastly, available demographic data on casino gambling hint at sex differences in the games played and the stakes wagered, but require further research for robust conclusions to be drawn.  相似文献   
246.
The most striking age-related change in the human adrenal cortex is the decline in secretion of dehydroepiandrosterone and its sulfate, steroids synthesized by the inner zone of the cortex, the zona reticularis. Because these steroids are of essentially unknown function, the importance of this age-related change is the subject of considerable debate. It is likely that the age-related change in these steroids results from loss of zona reticularis cells or impairment of their function. During aging, cumulative damage to the zona reticularis could occur through ischemia-related infarcts and other causes of cell death. Cellular senescence could contribute to a loss of the ability of the tissue to replace lost cells. In contrast, feedback mechanisms that regulate adrenocortical growth cause compensatory local tissue hyperplasias called nodules. The effect of imperfect repair of damage combined with compensatory overgrowth in the form of nodules leads to an increasingly abnormal tissue architecture.  相似文献   
247.
This study involves the development and initial validation of a questionnaire measuring the propensity for sexual inhibition and excitation in men: the Sexual Inhibition Sexual Excitation Scales (SIS/SES). The underlying theoretical model postulates that sexual response and associated behavior depend on dual control mechanisms, involving excitatory and inhibitory neurophysiological systems. The scales and their discriminant and convergent validity and test-retest reliability are described. In a sample of 408 sexually functional men (mean age = 22.8 years), factor analyses identified three higher-level factors: two related to sexual inhibition and one to sexual excitation. Multigroup Confirmatory Factor Analyses revealed that the factor structure provided an acceptable fit to the data obtained in a second (N = 459; mean age = 20.9 years) and third (N = 313; mean age = 46.2 years) sample of men, with similar distributions and relationships with other measures. Theoretical issues and areas for further research, including male sexual dysfunction and risk taking, are discussed.  相似文献   
248.
This study evaluated the predictive value of a newly developed measure of the propensity for sexual inhibition and excitation; the Sexual Inhibition Sexual Excitation Scales (SIS/SES). Sexual, cardiovascular, and startle responses were measured in a group of 40 sexually functional men during the presentation of threatening and nonthreatening erotic films. Two levels of performance demand were created and two films were combined with a distraction task. Participants were assigned to high and low groups for each of the three SIS/SES scales. As predicted, men with high SES scores showed generally higher sexual responses. High and low SIS1 groups did not differ in their responses. Men with high and low SIS2 scores did not differ in their responses to nonthreatening stimuli; however, low SIS2 men showed greater genital response to the threatening stimuli. The findings provide support for the value of the SIS/SES scales in predicting sexual responses.  相似文献   
249.
Representing knowledge: instances of management information   总被引:1,自引:0,他引:1  
Against the backdrop of discussions about the 'Information Society', the 'Informational Economy' and the role of IT in realizing organizational change we examine how representations of 'organizational knowledge' are constructed and used in work settings. We do this through the explication of ethnographic materials that detail the realization and use of Management Information (MI) in a major UK retail bank undergoing massive organizational change. We focus in particular on explicating how existing metric information was drawn upon to construct a representation of the work of the bank for those involved in managing that work. Systems designers have been increasingly interested in offering ways of conceptualizing the problem of 'knowledge' with a view to embedding these properties in systems. In the quest to develop representations of procedural knowledge to support work we argue that it is first necessary to understand how representations are actually created and used in work to support existing work practices.  相似文献   
250.
To examine correlates of the speed at which female soldiers carrying loads could cover 3.2 km on foot and traverse an obstacle course, 12 volunteers (mean +/- SD: 25.3 +/- 6 years, 166 +/- 7 cm, 61.3 +/- 7 kg) were timed over 3.2 km while carrying loads of 14, 27, and 41 kg, and while traversing an obstacle course with the two lighter loads. Pearson correlations showed that absolute VO_[2 max] and 3.2 km run time without a load were the best predictors of 3.2 km load carriage time for all loads. Also, larger subjects with greater muscle mass were able to carry the heaviest load faster than smaller, less muscular subjects, likely because the 41 kg load represented a smaller percentage of the former's bodyweight. Maximum number of sit-ups and push-ups, composite score of the Army Physical Fitness Test as well as body height were positively correlated with the speed at which some course segments were traversed.  相似文献   
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