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811.
Emerging adults (M = 18.99 years, SD = .50) completed cross-sectional questionnaires (N = 943) and targeted follow-up telephone surveys (N = 202) across the transition to college. Gender, personal goals (dating, friendship, academic), and past sexual behavior were examined as predictors of reasons to have and not to have sex. Men rated Self-focused reasons to have sex as more important; women rated Partner-focused reasons to have sex and Ethical reasons not to have sex as more important. Importance of Pregnancy/STD reasons not to have sex did not differ by gender. Before college entrance, sexual history and personal goals predicted endorsement of reasons for/against sex. Personal goals predicted first intercourse during freshman year. Limitations of the study include the single university sample and use of closed-ended self-report measures. Personal goals and reasons for/against sex are associated with sexual behavior and should be addressed in programs designed to promote sexual health among emerging adult college students.  相似文献   
812.
While the epidemiologic trends concerning alprazolam (Xanax) are unknown, the use of benzodiazepines, in general, has increased in popularity among youth within recent years. To shed light on the drug problem, the current pilot study used a qualitative approach to investigate relevant beliefs, norms, and perceived addiction associated with alprazolam initiation among 46 youth who were attending an inpatient drug treatment program during the spring of 2004. Overwhelmingly, most participants stated that addiction to alprazolam occurs as early as initial consumption. Most youth in the study stated that their friends felt it was normal to use alprazolam. In addition, their control beliefs revealed that if someone wanted to stop it would be difficult because of the widespread use in their communities and family social reinforcement involved with its use. In this study, a majority of students stated that medical professionals such as doctors and pharmacists were the greatest facilitator of alprazolam acquisition. Implications for these results are discussed.  相似文献   
813.
Alcohol use among college students is linked to an increased likelihood of engaging in risky sexual behaviors, including casual sex and unprotected sex. These behaviors increase college students' risks for negative social and health-related consequences. This study examined the relationship between drinking behaviors and protective behavioral strategies (PBS), expectancies and perceptions of sexual risk, and actual alcohol-related sexual behaviors and consequences. Sexually active college students completed Web-based self-report measures of drinking behaviors and use of PBS, alcohol expectancies and perceptions of risk, and sexual behaviors and related consequences (n = 524; 57.1% women). Findings indicated that PBS were related to lower expectancies of sexual risk and sexual disinhibition, and among lighter drinkers, lower expectancies of sexual enhancement from alcohol. PBS were also related to decreased perceptions of sexual-related risks, some alcohol-related sexual behaviors, including number of drinks before/during sex, and number of sexual consequences, but were not related to abstaining during sex, frequency of alcohol-related sexual behaviors, or general condom use. These findings demonstrate a disconnect between perceived and actual risks among college students, such that decreased perceptions of risk may not be associated with protective behaviors. Prevention and intervention implications are discussed.  相似文献   
814.
815.
We describe a Bayesian projection model to produce country-specific projections of the total fertility rate (TFR) for all countries. The model decomposes the evolution of TFR into three phases: pre-transition high fertility, the fertility transition, and post-transition low fertility. The model for the fertility decline builds on the United Nations Population Division’s current deterministic projection methodology, which assumes that fertility will eventually fall below replacement level. It models the decline in TFR as the sum of two logistic functions that depend on the current TFR level, and a random term. A Bayesian hierarchical model is used to project future TFR based on both the country’s TFR history and the pattern of all countries. It is estimated from United Nations estimates of past TFR in all countries using a Markov chain Monte Carlo algorithm. The post-transition low fertility phase is modeled using an autoregressive model, in which long-term TFR projections converge toward and oscillate around replacement level. The method is evaluated using out-of-sample projections for the period since 1980 and the period since 1995, and is found to be well calibrated.  相似文献   
816.
Analysis of a sample of 2084 child abuse referrals to the NSPCC Child Protection Helpline showed that in 10% a parent or carer was reported as having a mental health problem. Mothers were the parent affected in the majority of these cases. The mental health sample differed from the other referrals in an increased concern about emotional abuse and less about sexual abuse; greater levels of violence and discord between parents; and more agency involvement. Issues of potential labelling and therapeutic needs are discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
817.
818.
We show that optimal monetary and fiscal policies are time consistent for a class of economies often used in applied work, economies appealing because they are consistent with the growth facts. We establish our results in two steps. We first show that for this class of economies, the Friedman rule of setting nominal interest rates to zero is optimal under commitment. We then show that optimal policies are time consistent if the Friedman rule is optimal. For our benchmark economy in which the time consistency problem is most severe, the converse also holds: if optimal policies are time consistent, then the Friedman rule is optimal.  相似文献   
819.
New dynamic benchmarks are developed as performance metrics for operational activities in the ingot mill of an aluminium smelter. This new type of high-level performance measure enables both a systematic and a holistic appraisal of operations performance that is not possible at present. The benchmarks also allow changes in performance of each distinct resource group to be clearly identified. The method for computing such measures is based on a wide range of shop-floor data, and possibility theory is used to model the soft characteristics of much of the input. Fuzzy performance estimates are dynamically updated with special attention to combining the different forms of uncertainty that exist in the input information. Although these procedures are site specific, the methodology is applicable to other types of manufacturing systems.  相似文献   
820.
Patrick A. Puhani 《LABOUR》2002,16(3):569-608
I estimate the employment effects of publicly financed training and intervention works (subsidized employment) programmes in Poland. The analysis is based on the Polish Labour Force Survey (PLFS). Two widely applied approaches to identify causal effects are used. The results are qualitatively invariant with respect to the applied methodology. I find some evidence that training improves the employment opportunities of both men and women, whereas intervention works do not. Previous findings using PLFS data thus seem to be robust. The contrary view expressed by other authors on intervention works (subsidized employment) is likely to stem from the different data source (on only some Polish regions and with fewer control variables) used by them and does not seem to be related to the estimation strategy.  相似文献   
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