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81.
An increasing body of evidence now suggests the involvement of mitochondrial abnormalities in the etiology of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer disease. In this Perspective, we describe a recent study that shows that treatment of human patients with the antioxidant coenzyme Q(10'), which functions in concert with certain mitochondrial enzymes, reduced the worsening of symptoms associated with PD. These findings are consistent with the hypothesis that mitochondrial dysfunction plays a role in the pathogenesis of PD and that treatments that target mitochondrial biochemistry might ameliorate the functional decline observed in patients suffering from PD.  相似文献   
82.
This article investigates how accurately experts (underwriters) and lay persons (university students) judge the risks posed by life-threatening events Only one prior study (Slovic, Fischhoff, & Lichtenstein, 1985) has previously investigated the veracity of expert versus lay judgments of the magnitude of risk. In that study, a heterogeneous grouping of 15 experts was found to judge, using marginal estimations, a variety of risks as closer to the true annual frequencies of death than convenience samples of the lay population. In this study, we use a larger, homogenous sample of experts performing an ecologically valid task. We also ask our respondents to assess frequencies and relative frequencies directly, rather than ask for a "risk" estimate--a response mode subject to possible qualitative attributions-as was done in the Slovic et al. study. Although we find that the experts outperformed lay persons on a number of measures, the differences are small, and both groups showed similar global biases in terms of: (1) overestimating the likelihood of dying from a condition (marginal probability) and of dying from a condition given that it happens to you (conditional probability), and (2) underestimating the ratios of marginal and conditional likelihoods between pairs of potentially lethal events. In spite of these scaling problems, both groups showed quite good performance in ordering the lethal events in terms of marginal and conditional likelihoods. We discuss the nature of expertise using a framework developed by Bolger and Wright (1994), and consider whether the commonsense assumption of the superiority of expert risk assessors in making magnitude judgments of risk is, in fact, sensible.  相似文献   
83.
The Comprehensive Everglades Restoration Plan, enacted in 2000, is a $7.8 billion federal/state investment in restoring the Florida Everglades ecosystem. The plan is a negotiated compromise between divergent interests in south Florida and promises to provide water and flood control for urban and agricultural users while maintaining a priority commitment to the natural system when allocating water produced by the 30-year project. The environmental community calls for independent scientific review of un-tested technologies, early and substantial hydrologic benefits to the remaining Everglades, including Everglades National Park, and strong programmatic regulations of the federal project to ensure that ecological restoration remains its primary purpose in spite of inherently conflicting interests at the state and local level.  相似文献   
84.
The use of 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") appears to be increasing worldwide, with "rave" attendees being one high-risk population. To date, however, only one study has collected ecstasy use information from rave attendees in the United States. To address this limitation, we collected self-report drug use information from 70 adult "club rave" attendees within the Baltimore-Washington corridor in April and May 2002. Data collection was scheduled between 12 A.M. and 5 A.M. Participation rates were high, with 85 percent of the club rave attendees completing the interview. Eighty-six percent of the respondents reported lifetime ecstasy use, 51 percent reported 30-day use, and 30 percent reported using ecstasy within the two days preceding the interview. While past-year ecstasy users were comparable to non-users with respect to a host of demographic and drug use variables, non-ecstasy users were significantly more likely than past-year users to perceive risks associated with the regular use of alcohol and ecstasy. Not surprisingly, non-ecstasy users were significantly more likely than past-year users to perceive harmful long-term physical and psychological effects associated with ecstasy ingestion. These findings suggest that rave attendees may be an important population for ecstasy-related prevention efforts.  相似文献   
85.
In the current study, we used a qualitative approach to investigate relevant beliefs and norms associated with codeine and promethazine hydrochloride cough syrup (CPHCS) consumption, initiation, and perceived addiction among 48 alternative school students who identified themselves as current CPHCS users. In general, both boys and girls believed that CPHCS addiction started during an individual's initial consumption. A majority of both groups reported that their second CPHCS event was initiated during the same or next day after their first event. Our findings suggest that friends and an innovative form of hip-hop music called "screw" are strong reinforcers of CPHCS use.  相似文献   
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Human-dominated ecosystems such as in South Florida's Everglades region are greatly affected by societal actions and choices, and efforts to restore degraded ecosystems must take into account the societal drivers of ecosystem change. A conceptual model of societal-ecological interactions within the region illustrates connections between major societal drivers, such as water management and land use, and ecological stressors, such as loss of habitat and nutrient loading. Using the conceptual model as an initial guide for discussion, examination of a restoration scenario for the region shows that social and economic effects from activities proposed in a restoration scenario will likely affect most sectors of South Florida. Political effects from changing land and water management practices likely will be significant, as will the physical effects of changing water structures and management practices. Conceptual models such as this can aid in the initial stages of ecosystem restoration discussions and can assist in planning for subsequent social science evaluations of specific societal impacts of actual proposed governmental restoration alternatives. In crafting restoration scenarios, local, regional, and national decision makers can use conceptual models such as this to help broaden the early considerations of how possible future changes in societal drivers, including management choices, will change ecological stressors that affect ecosystem health.  相似文献   
89.
Much leadership literature neglects its historical-contextual antecedents and as a result over-emphasizes zeitgeist, or tenor of the time's social forces. This neglect impedes leadership research by encouraging academic amnesia and promoting a strong feeling of research déjà vu among many researchers and practitioners. In this article, we develop a leadership historical-contextual superstructure consisting of evolutionary antecedents, paradigmatic antecedents, purpose and definitional antecedents, stakeholder antecedents, levels of analysis and temporal antecedents, and research dissemination antecedents. We use this superstructure to analyze current work in the increasingly important relational leadership research stream to illustrate how the superstructure's use can aid leadership researchers and practitioners in avoiding leadership déjà vu and academic amnesia and help build a more cumulative field.  相似文献   
90.
Converse's definition of ideological contraint is expanded to provide for various respondent identified ideological dimensions rather than an all encompassing liberal-conservative dimension. Using this redefinition a sample of adults is shown to have high levels of ideological constraint. Ideological constraint is shown to vary with the degree of cognitive complexity and the degree of preference evaluability. The latter is a new concept that suggests that some issues will be easier for a respondent to demonstrate constraint on depending upon the availability and applicability of preference criteria. Salience is also shown to have a positive relationship with ideological constraint, but only when preference evaluability is high.  相似文献   
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