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961.
Jonsson SH  Rendall MS 《Demography》2004,41(1):129-150
Crucial to the long-term contribution of immigration to a receiving country's population is the extent to which the immigrants reproduce themselves in subsequent, native-born generations. Using conventional projection methodologies, this fertility contribution may be poorly estimated primarily because of problems in projecting the number of immigrants who are at risk of childbearing. We propose an alternative method that obviates the need to project the number of immigrants by using the full sending-country birth cohort as the risk group to project their receiving-country childbearing. This "sending-country birth cohort" method is found to perform dramatically better than conventional methods when projecting to 1999 from base years both before and after the large increase in inflows of Mexican immigrants to the United States in the late 1980s. Projecting forward from 1999, we estimate a cumulative contribution of Mexican immigrant fertility from the 1980s to 2040 of 36 million births, including 25% to 50% more births after 1995 than are projected using conventional methods.  相似文献   
962.
Twenty-four-hour recall data from the Continuing Survey of Food Intake by Individuals (CSFII) are frequently used to estimate dietary exposure for risk assessment. Food frequency questionnaires are traditional instruments of epidemiological research; however, their application in dietary exposure and risk assessment has been limited. This article presents a probabilistic method of bridging the National Health and Nutrition Examination Survey (NHANES) food frequency and the CSFII data to estimate longitudinal (usual) intake, using a case study of seafood mercury exposures for two population subgroups (females 16 to 49 years and children 1 to 5 years). Two hundred forty-nine CSFII food codes were mapped into 28 NHANES fish/shellfish categories. FDA and state/local seafood mercury data were used. A uniform distribution with minimum and maximum blood-diet ratios of 0.66 to 1.07 was assumed. A probabilistic assessment was conducted to estimate distributions of individual 30-day average daily fish/shellfish intakes, methyl mercury exposure, and blood levels. The upper percentile estimates of fish and shellfish intakes based on the 30-day daily averages were lower than those based on two- and three-day daily averages. These results support previous findings that distributions of "usual" intakes based on a small number of consumption days provide overestimates in the upper percentiles. About 10% of the females (16 to 49 years) and children (1 to 5 years) may be exposed to mercury levels above the EPA's RfD. The predicted 75th and 90th percentile blood mercury levels for the females in the 16-to-49-year group were similar to those reported by NHANES. The predicted 90th percentile blood mercury levels for children in the 1-to-5-year subgroup was similar to NHANES and the 75th percentile estimates were slightly above the NHANES.  相似文献   
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966.
This study describes depressive symptoms among caregivers following bereavement and connects these trajectories to earlier features of caregiving using life course and stress process theory. Data are from a six-wave longitudinal survey (five years) of spouses and adult children caring for someone with Alzheimer's Disease. The analytic subsample (N = 291) is defined by death of the care-recipient after the baseline interview. A latent class mixture model is used to identify distinctive clusters of depressive symptoms over time. Of the four trajectories identified, three represent stable symptom levels over time, with two-thirds being repeatedly symptomatic (medium symptom levels), compared to two smaller groups of repeatedly asymptomatic (effectively absent of symptoms) and repeatedly distressed (severe symptoms). In contrast, about one in five caregivers experiences improved emotional well-being over time, the temporarily distressed, who progress from severe to moderate symptom levels. Caregivers with few symptoms before bereavement tend to maintain these states afterwards, but emotionally distressed caregivers tend to become more distressed. Role overload before bereavement substantially increases the odds of following an unfavorable trajectory afterwards, whereas self-esteem and socioemotional support play protective roles. These results demonstrate that caregivers are not uniform in their emotional responses to bereavement, but follow several distinct trajectories. These trajectories are linked to their previous experiences as caregivers, in particular exposure to stressors and access to resources. These findings suggest that intervention during caregiving may facilitate adaptation following death of a loved one.  相似文献   
967.
Anecdotal reports have suggested that the use and abuse of methamphetamine is increasing in the United States. To date, however, few scholarly works have explored the prevalence and correlates of methamphetamine use in the United States. To address this limitation, a secondary analysis was undertaken with data collected through the Arrestee Drug Abuse Monitoring (ADAM) Program. An examination of methamphetamine-positive rates among ADAM arrestees interviewed between 1991 and 2001 identified that its use is concentrated within the Western part of the United States. Supplementary analyses of Sacramento arrestees indicated that 71% were diagnosed as needing some form of alcohol or other drug treatment. Compared to those arrestees who were detected methamphetamine-negative, methamphetamine-positive arrestees in Sacramento were three times as likely to be white and to have been diagnosed in need of drug treatment. Implications for drug control policy are discussed.  相似文献   
968.
A group of friends consider renting a house but they shall first agree on how to allocate its rooms and share the rent. We propose an auction mechanism for room assignment-rent division problems which mimics the market mechanism. Our auction mechanism is efficient, envy-free, individually-rational and it yields a non-negative price to each room whenever that is possible with envy-freeness.We would like to thank seminar participants at Barcelona, Boston College, Duke, Koç, Málaga, MIT, Michigan, NYU, conference participants at the First Brazilian Workshop of Game Theory Society (Sao Paulo 2002), SED 2002-Conference on Economic Design (New York City 2002), The Sixth International Meeting of the Society for Social Choice and Welfare (Pasadena 2002), an anonymous referee for their comments and Ahmet Alkan, Selçuk Karabati, Bari Tan, nsan Tunali for insightful discussions. Sönmez gratefully acknowledges the research support of KoçBank via the KoçBank scholar program and Turkish Academy of Sciences in the framework of the Young Scientist Award Program via grant TS/TÜBA-GEBP/2002-1-19. Any errors are our own responsibility.  相似文献   
969.
This study examines demographic and situational factors in an effort to predict whether or not a complainant was injured, used resistance, experienced a completed assault, and whether charges were brought against the offender. If the accused had consumed alcohol or drugs, he was almost seven times more likely to be arrested. The complainant was six times more likely to report rape completion if she had consumed alcohol or drugs and if the complainant fell unconscious at any time during the attack she was significantly less likely to use a resistance strategy. The complainant's use of a compliance strategy at any time during the assault positively predicted not using a physical resistance strategy and sexual assault completion. The reporting of injury positively predicted use a physical resistance strategy and sexual assault completion. If the assault was completed, it was less likely that charges were pressed. Implications of these findings are discussed, and directions for future research are offered.  相似文献   
970.
Is it more effective to reduce poverty among the elderly by increasing the benefits paid by the Supplemental Security Income (SSI) program or by increasing eligibility for the program? This paper answers that question from a policymaker's perspective. At given program cost levels, we compare the potential reduction in poverty from increasing benefit levels to the potential reduction associated with a variety of policy proposals that would increase eligibility for the program. This paper employs a microsimulation model containing an eligibility and benefits calculator, a participation model, and an optimization algorithm. The data are from the Survey of Income and Program Participation supplemented by the administrative records of the SSI program. The results show that increasing eligibility by relaxing the restrictions of the means tests can be more effective in reducing poverty than raising benefit levels.  相似文献   
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