全文获取类型
收费全文 | 8888篇 |
免费 | 233篇 |
专业分类
管理学 | 1213篇 |
民族学 | 45篇 |
人才学 | 1篇 |
人口学 | 828篇 |
丛书文集 | 40篇 |
理论方法论 | 813篇 |
综合类 | 302篇 |
社会学 | 3988篇 |
统计学 | 1891篇 |
出版年
2023年 | 42篇 |
2021年 | 55篇 |
2020年 | 108篇 |
2019年 | 162篇 |
2018年 | 194篇 |
2017年 | 288篇 |
2016年 | 244篇 |
2015年 | 165篇 |
2014年 | 197篇 |
2013年 | 1555篇 |
2012年 | 326篇 |
2011年 | 263篇 |
2010年 | 210篇 |
2009年 | 191篇 |
2008年 | 226篇 |
2007年 | 210篇 |
2006年 | 177篇 |
2005年 | 232篇 |
2004年 | 209篇 |
2003年 | 251篇 |
2002年 | 261篇 |
2001年 | 231篇 |
2000年 | 211篇 |
1999年 | 209篇 |
1998年 | 153篇 |
1997年 | 126篇 |
1996年 | 139篇 |
1995年 | 118篇 |
1994年 | 110篇 |
1993年 | 127篇 |
1992年 | 141篇 |
1991年 | 131篇 |
1990年 | 120篇 |
1989年 | 111篇 |
1988年 | 120篇 |
1987年 | 119篇 |
1986年 | 107篇 |
1985年 | 129篇 |
1984年 | 104篇 |
1983年 | 112篇 |
1982年 | 84篇 |
1981年 | 84篇 |
1980年 | 74篇 |
1979年 | 77篇 |
1978年 | 81篇 |
1977年 | 60篇 |
1976年 | 49篇 |
1975年 | 60篇 |
1974年 | 50篇 |
1973年 | 41篇 |
排序方式: 共有9121条查询结果,搜索用时 500 毫秒
41.
Stuart Barber Guy P. Nason 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2004,66(4):927-939
Summary. Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients. 相似文献
42.
魏晋南北朝是中国古代动乱最多、人民生活最悲惨的时代。战争、动乱使汉王朝“独尊儒术”的旧思想体制大崩溃 ,导致魏晋南北朝时期的古代中国思想最解放、最自由。美学思想和精神的自由 ,酿就了艺术创造精神的勃发 ,因而新的艺术形式、艺术规律应运而生并相互融会贯通。此时的盆景艺术正是在绘画、园林、盆栽、赏石等艺术形式的影响下孕育了自己最初的表现形式和美学规律 ,因此可以说该时期是盆景发展史上的一个重要阶段 相似文献
43.
Michaela L. Z. Farber Elizabeth Timberlake Helen Patricia Mudd Linda Cullen 《Child and Adolescent Social Work Journal》2003,20(3):175-196
To prepare for the complexities of family formation, 78 prospective adoptive parents participated in Pre-Adopt, a psychosocial educational orientation program offered by one private nonprofit agency. The five-session curriculum included an overview of adoption policies and procedures, discussion of the child placement process, exploration of couples' adoption concerns and expectations about child characteristics, information about adoption laws and birth-parent/child searches, and examination of anticipatory fantasies about birth parents. Program evaluation yielded statistically significant and clinically meaningful findings about changes in emotional readiness to adopt, parenting knowledge, and satisfaction with group participation, adoption policies and agency practices. Practice implications are considered. 相似文献
44.
Abstract This study examines the contentions of two recent perspectives on rural economic organization and their implications for poverty. Building from (1) agrarian political economy and (2) the rural restructuring literatures, we present a comparative regional analysis of how farming patterns and other aspects of economic organization differentially affect poverty in rural areas. Data are based on 2,349 nonmetropolitan U.S. counties for the 1970–1980 period. Nonhired labor-dependent, family-operated farming (smaller and larger family farming) has relatively similar cross-regional effects on rural poverty. The effects of industrialized farming are more spatially variant, suggesting that this type of farming is integrated into regional political economies in different ways than are simple commodity units. However, farming patterns have only a small effect on rural poverty relative to other factors, such as the local employment structure, characteristics of the population, and geographic location. The results of this study highlight the need to move beyond the farm sector to understand both the dynamics of this sector and the socioeconomic consequences of rural restructuring. More broadly, the study underscores the importance of testing general sociological relationships under different spatial (e.g., regional) contexts. 相似文献
45.
William R. Shadish Kevin Ragsdale Renita R. Glaser Linda M. Montgomery 《Journal of marital and family therapy》1995,21(4):345-360
This article reviews the major findings from a multiproject meta-analysis of the effects of marital and family therapy (MFT). Across 163 randomized trials, MFT demonstrates moderate, statistically significant, and often clinically significant effects. No orientation is yet demonstrably superior to any other, nor is MFT superior to individual therapy. Cost effectiveness information is scant in these 163 studies, but supportive. Randomized experiments yield very different answers from nonrandomized experimental studies of the effects of MFT, calling into question whether we should mix the two in reviews. We have also found several new differences in the ways that marital therapy (MT) and family therapy (FT) studies are conducted, making them harder to compare. Finally, important questions still exist about whether any psychotherapy, including MFT, yet has sufficient information about how well research generalizes to everyday clinical practice. 相似文献
46.
TESTAMENTARY BEHAVIOR: 总被引:1,自引:0,他引:1
T.P. Schwartz 《The Sociological quarterly》1993,34(2):337-355
Content analysis and qualitative analysis of all 319 last wills that were filed in Providence Probate Court, 1985, revealed that about ten percent of the testators used testamentary material, disinheritance or altruism to express their individuality. About 42 percent of the wills were personalized directly in other ways. Forty-eight percent displayed indirect influences of family, friends and community. Less that ten percent displayed primary influences of attorneys, banks, nursing homes, governments, religions or other organizations. In the light of these findings, while none of the three major theoretical positions on testamentary behavior prevails, the individualist position is manifested more often than is the family-community position. Both of these positions are manifested much more often than is the legalist position.
These findings are related to the work of Emile Durkheim and to contemporary sociological theories of the family, community and law. 相似文献
These findings are related to the work of Emile Durkheim and to contemporary sociological theories of the family, community and law. 相似文献
47.
The authors investigated the prevalence of recurrent pain in a college student sample. Of the 1,564 students surveyed, 467 (29%) indicated that they had experienced recurrent pain at an intensity that was mostly in the mild-to-moderate range. Students who reported having recurrent pain were significantly older and more depressed than students who did not indicate they suffered from recurrent pain. Pain intensity was positively correlated (r = .14) with depression among the students who reported having recurrent pain. Implications of the findings for future research, treatment, and health promotion efforts are discussed. 相似文献
48.
This study investigated the gender-specific, self-reported sexual behaviors and attitudes of never-married college students attending a southeastern university in 1973 and 1988. Data were collected by means of a mailed questionnaire that remained essentially unchanged for both years. The authors found that both men and women reported an increase in heterosexual relationships that included sexual intercourse and a decrease in nonsexual relationships with the other gender. The majority of the students perceived themselves as adequately informed about sexuality and satisfied with their relationships, although the proportion of men who reported being satisfied with their relationships declined over the 15 years. The students indicated that sexuality education should focus primarily on information about AIDS and on preparation for marriage. 相似文献
49.
樊宝敏 《北京林业大学学报(社会科学版)》2003,2(3):69-74
张钧成先生是我国著名的林业历史学家.该文从林业史学科建设、林业史研究概况、中国古代林业通史、中国古代林业思想和传统文化、林业科技史和经济史、近现代林业史等研究领域,概述了张先生的学术成就,并回顾了张先生高尚的人生哲学和宝贵的治学经验.张先生的研究成果和治学经验,为我国林史学科的发展奠定了基础. 相似文献
50.
Luis F. B. Plascencia Gary P. Freeman Mark Setzler 《The International migration review》2003,37(1):5-23
State governments exercise significant powers to regulate the economic and social activities of resident aliens. We review the laws of the six leading states of immigrant settlement regulating access of noncitizens to 23 occupations, updating existing studies from 1946–77. Citizenship requirements for these occupations have plummeted, a change we attribute to federal court decisions, advisory opinions of state attorneys general, and state legislative and administrative action. There are numerous additional citizenship requirements in the statutes of the six states, although these appear to be poorly enforced. The authority of states to regulate their political communities is the most important remaining constitutionally valid basis of citizenship requirements. States define their political community broadly, leading to questionable exclusions of noncitizens from important activities. 相似文献