全文获取类型
收费全文 | 23494篇 |
免费 | 761篇 |
国内免费 | 201篇 |
专业分类
管理学 | 1141篇 |
劳动科学 | 55篇 |
民族学 | 653篇 |
人才学 | 22篇 |
人口学 | 408篇 |
丛书文集 | 5680篇 |
理论方法论 | 1131篇 |
综合类 | 13061篇 |
社会学 | 975篇 |
统计学 | 1330篇 |
出版年
2024年 | 17篇 |
2023年 | 87篇 |
2022年 | 314篇 |
2021年 | 356篇 |
2020年 | 290篇 |
2019年 | 222篇 |
2018年 | 309篇 |
2017年 | 489篇 |
2016年 | 376篇 |
2015年 | 678篇 |
2014年 | 875篇 |
2013年 | 1179篇 |
2012年 | 1331篇 |
2011年 | 1684篇 |
2010年 | 1745篇 |
2009年 | 1801篇 |
2008年 | 1764篇 |
2007年 | 1907篇 |
2006年 | 1870篇 |
2005年 | 1599篇 |
2004年 | 954篇 |
2003年 | 805篇 |
2002年 | 1036篇 |
2001年 | 830篇 |
2000年 | 511篇 |
1999年 | 342篇 |
1998年 | 177篇 |
1997年 | 159篇 |
1996年 | 179篇 |
1995年 | 123篇 |
1994年 | 100篇 |
1993年 | 75篇 |
1992年 | 82篇 |
1991年 | 42篇 |
1990年 | 34篇 |
1989年 | 25篇 |
1988年 | 33篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Guided by Cantor’s social care model, this study identified individual, family, and social support factors that influence urban older adults’ need for home- and community-based services, including medical and rehabilitation, instrumental care and support, and psychosocial services. The data were extracted from the Sample Survey on Aged Population in Urban/Rural China conducted by the China Research Center on Aging in 2006. Results from multiple logistic regression show that older adults’ need for medical and rehabilitation services is significantly related to instrumental activities of daily living, depression, not having filial children, friend support networks, and having a confidant. Older adults’ need for instrumental care and support is related to their educational attainment, financial strain, instrumental activities of daily living, not living with children, and friend support networks. Finally, older adults’ need for psychosocial services is significantly related to educational attainment, depression, not being married, friend support networks, and having a confidant. Implications for social service development are discussed. 相似文献
992.
Kamila Dvořáková Moé Kishida Jacinda Li Steriani Elavsky Patricia C. Broderick Mark R. Agrusti 《Journal of American college health : J of ACH》2017,65(4):259-267
Objective: Given the importance of developmental transitions on young adults' lives and the high rates of mental health issues among U.S. college students, first-year college students can be particularly vulnerable to stress and adversity. This pilot study evaluated the effectiveness and feasibility of mindfulness training aiming to promote first-year college students' health and wellbeing. Participants: 109 freshmen were recruited from residential halls (50% Caucasian, 66% female). Data collection was completed in November 2014. Methods: A randomized control trial was conducted utilizing the Learning to BREATHE (L2B) program, a universal mindfulness program adapted to match the developmental tasks of college transition. Results: Participation in the pilot intervention was associated with significant increase in students' life satisfaction, and significant decrease in depression and anxiety. Marginally significant decrease was found for sleep issues and alcohol consequences. Conclusions: Mindfulness-based programs may be an effective strategy to enhance a healthy transition into college. 相似文献
993.
En Li Matthew Browne Vijay Rawat Erika Langham Matthew Rockloff 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2017,33(1):223-248
This article examines gambling harms from both gamblers and affected others’ perspectives. Participants (3076 gamblers and 2129 affected others) completed a retrospective survey that elicited information on harms they experienced from gambling across their lifetime. Their responses were analyzed through testing measurement invariance, estimating item-response theoretic parameters, calculating percentages, confidence intervals, and correlations, as well as regressions. The results indicated large commonalities in the experience of harms reported by gamblers and affected others. Further, gamblers appeared to ‘export’ about half of the harms they experienced to those around them. The findings also provided detailed profiles of evolving harms as problem gambling severity varies. 相似文献
994.
Xiao-Hua Yu Jing Zhao Shu-Cheng Zhang Jian-Hui Li Jun-Biao Zheng Zheng Li 《The aging male》2017,20(4):235-240
Objective: To analyze the impact of age, BMI and sex hormone on aging males’ symptoms (AMS) and the 5-item version of the international index of erectile function (IIEF-5) scores in middle-aged and elderly Chinese men.Methods: A population-based cross-sectional study was conducted in Jiashan County. A total of 969 men, aged between 40 and 80 years old, were admitted. Physical examination and the sex hormones were measured, and AMS and IIEF-5 scores were assessed.Results: The oneway ANOVA analysis indicated older age groups had higher AMS total-scores, somatic and sexual sub-scores, and lower IIEF5 scores (all p?.01). Pairwise correlation (rpairwise) analyses showed the significant associations between AMS and age or sex hormone (cFT, Bio-T, SHBG, and LH) levels, and similar for IIEF5. However, when age was adjusted, the correlation coefficients (rpartial) weakened, and correlation significance disappeared, except LH (for AMS: rpartial?=?0.096, p?=?.009; for IIEF-5: rpartial?= ?0.140, p?=?.001). Multiple linear regressions confirmed the influence of increased age and LH on the AMS and IIEF5 scores.Conclusion: CFT, Bio-T and SHBG failed to yield any additional predicting information when age was adjusted. To improve the male reproductive health, future research should pay more attention on aging-related comorbidities and how to improve general wellness. 相似文献
995.
Measuring the difference between two Gini indexes is important in comparing the inequality between two groups. This paper systematically provides confidence intervals for this difference. First, normal approximation- and bootstrap-based confidence intervals are provided for the difference. Second, empirical likelihood (EL)-based confidence intervals are proposed according to a ratio statistic that is proven to have a weighted Chi-squared distribution with one degree of freedom. Third, two calibration approaches are established to improve the undercoverage issue of the EL method; these two approaches are augmented EL and bootstrap-calibrated EL. Monte Carlo simulations show that bootstrap-calibrated EL generally outperforms other methods in constructing confidence intervals. In the simulations, these methods are compared with the permutation method to test the equality of two Gini indexes. Lastly, these methods are applied to real data. 相似文献
996.
Chi-Rong Li 《Journal of Statistical Computation and Simulation》2017,87(10):1940-1950
This study constructs a simultaneous confidence region for two combinations of coefficients of linear models and their ratios based on the concept of generalized pivotal quantities. Many biological studies, such as those on genetics, assessment of drug effectiveness, and health economics, are interested in a comparison of several dose groups with a placebo group and the group ratios. The Bonferroni correction and the plug-in method based on the multivariate-t distribution have been proposed for the simultaneous region estimation. However, the two methods are asymptotic procedures, and their performance in finite sample sizes has not been thoroughly investigated. Based on the concept of generalized pivotal quantity, we propose a Bonferroni correction procedure and a generalized variable (GV) procedure to construct the simultaneous confidence regions. To address a genetic concern of the dominance ratio, we conduct a simulation study to empirically investigate the probability coverage and expected length of the methods for various combinations of sample sizes and values of the dominance ratio. The simulation results demonstrate that the simultaneous confidence region based on the GV procedure provides sufficient coverage probability and reasonable expected length. Thus, it can be recommended in practice. Numerical examples using published data sets illustrate the proposed methods. 相似文献
997.
A variable sample size (VSS) scheme directly monitoring the coefficient of variation (CV), instead of monitoring the transformed statistics, is proposed. Optimal chart parameters are computed based on two criteria: (i) minimizing the out-of-control ARL (ARL1) and (ii) minimizing the out-of-control ASS (ASS1). Then the performances are compared between these two criteria. The advantages of the proposed chart over the VSS chart based on the transformed statistics in the existing literature are: the former (i) provides an easier alternative as no transformation is involved and (ii) requires less number of observations to detect a shift when ASS1 is minimized. 相似文献
998.
In the 1960s and 1970s, the countries of Central and Eastern Europe and the Soviet Union experienced an unanticipated stagnation in the process of mortality reduction that was accelerating in the west. This was followed by even starker fluctuations and overall declines in life expectancy during the 1980s and 1990s. We identify statistically the extent to which, since the 1990s, the countries of the post-communist region have converged as a group towards other regional or cross-regional geopolitical blocks, or whether there are now multiple steady-states (‘convergence clubs’) emerging among these countries. We apply a complex convergence club methodology, including a recursive analysis, to data on 30 OECD countries (including 11 post-communist countries) drawn from the Human Mortality Database and spanning the period 1959–2010. We find that, rather than converging uniformly on western life expectancy levels, the post-communist countries have diverged into multiple clubs, with the lowest seemingly stuck in low-level equilibria, while the best performers (e.g. Czech Republic) show signs of catching-up with the leading OECD countries. As the post-communist period has progressed, the group of transition countries themselves has become more heterogeneous and it is noticeable that distinctive gender and age patterns have emerged. We are the first to employ an empirical convergence club methodology to help understand the complex long-run patterns of life expectancy within the post-communist region, one of very few papers to situate such an analysis in the context of the OECD countries, and one of relatively few to interpret the dynamics over the long-term. 相似文献
999.
China’s middle-aged and older women suffer from poorer health than men. Using national baseline data from the China Health and Retirement Longitudinal Study (CHARLS), a survey conducted from 2011 to 2012, this article applies logistic models to investigate the association between female fertility history (parity, early childbearing, late childbearing) and middle-aged and late-life health. We find that parity is related to the mid-late-life health of women. Women with four children or more are more likely to suffer from activities of daily living (ADL) impairment and poorer self-rated health than those with one to three children. Early childbearing is associated with ADL impairment; however, the correlation is mediated by socioeconomic status. Early childbearing is related to self-rated health in later life by an indirect-only mediation effect via educational attainment and personal income. 相似文献
1000.
Robin S. Cronin Minglan Li Kate Culliney Robyn Maude Katherine Nelson 《Women and birth : journal of the Australian College of Midwives》2018,31(5):422-429