首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2062篇
  免费   106篇
管理学   245篇
民族学   17篇
人口学   183篇
丛书文集   13篇
理论方法论   247篇
综合类   17篇
社会学   1236篇
统计学   210篇
  2023年   25篇
  2022年   12篇
  2021年   23篇
  2020年   54篇
  2019年   64篇
  2018年   60篇
  2017年   119篇
  2016年   89篇
  2015年   47篇
  2014年   78篇
  2013年   335篇
  2012年   97篇
  2011年   90篇
  2010年   71篇
  2009年   63篇
  2008年   82篇
  2007年   80篇
  2006年   85篇
  2005年   63篇
  2004年   65篇
  2003年   49篇
  2002年   59篇
  2001年   43篇
  2000年   27篇
  1999年   35篇
  1998年   26篇
  1997年   24篇
  1996年   28篇
  1995年   21篇
  1994年   18篇
  1993年   15篇
  1992年   13篇
  1991年   17篇
  1990年   9篇
  1989年   19篇
  1988年   15篇
  1987年   16篇
  1986年   8篇
  1985年   11篇
  1984年   12篇
  1983年   12篇
  1982年   16篇
  1981年   5篇
  1980年   9篇
  1979年   10篇
  1977年   8篇
  1974年   6篇
  1970年   5篇
  1969年   4篇
  1968年   4篇
排序方式: 共有2168条查询结果,搜索用时 750 毫秒
121.
Using the eye gaze of others to direct one's own attention develops during the first year of life and is thought to be an important skill for learning and social communication. However, it is currently unclear whether infants differentially attend to and encode objects cued by the eye gaze of individuals within familiar groups (e.g., own race, more familiar sex) relative to unfamiliar groups (e.g., other race, less familiar sex). During gaze cueing, but prior to the presentation of objects, 10‐month‐olds looked longer to the eyes of own‐race faces relative to 5‐month‐olds and relative to the eyes of other‐race faces. After gaze cueing, two objects were presented alongside the face and at both ages, infants looked longer to the uncued objects for faces from the more familiar‐sex and longer to cued objects for the less familiar‐sex faces. Finally, during the test phase, both 5‐ and 10‐month‐old infants looked longer to uncued objects relative to cued objects but only when the objects were cued by an own‐race and familiar‐sex individual. Results demonstrate that infants use face eye gaze differently when the cue comes from someone within a highly experienced group.  相似文献   
122.
The smartphone app market is a prime example of a digital market where consumers are tasked with selecting one option among a plethora of alternatives, at times indistinguishable from one another. Building upon findings on information processing and decision-making, we postulate that consumers follow simple (rather than complex) heuristic rules to navigate the app market. In particular, we focus on two such strategies: the recognition heuristic and the majority vote heuristic. App privacy information was also considered as a potentially salient cue in the decision-making process, given the personal data stored on smartphones. Results of a mixed-method design (behavioral analysis and think-aloud protocols) study with German (N?=?18) and US (N?=?25) students find a dominance of the recognition heuristic. Decisions are further supported by majority vote heuristics. Privacy information is largely disregarded, particularly by US participants. Implications for app market design and engagement are discussed.  相似文献   
123.
Introduction: The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men.

Methods: 22 lifetime sedentary (SED; 62?±?2 years) and 17 masters’ athletes (LEX; 60?±?5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay.

Results: IGF-I was higher in LEX compared to SED at baseline (p?=?0.007, Cohen’s d?=?0.91), and phase B (p?=?0.083, Cohen’s d?=?0.59), with only a small difference at C (p?=?0.291, Cohen’s d?=?0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1?±?4.7 to 14.2?±?6.0?μg·dl?1 (p?=?0.376, Cohen’s d?=?0.22), followed by a larger increase post-HIIT (16.9?±?4.4?μg·dl?1), which was significantly elevated compared with baseline (p?=?0.002, Cohen’s d?=?0.85), and post-preconditioning (p?=?0.005, Cohen’s d?=?0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2?±?6.4 to 17.2?±?3.7?μg·dl?1 [p?=?0.538, Cohen’s d?=?0.19]), and a small change post-HIIT (18.4?±?4.1?μg·dl?1 [p?=?0.283, Cohen’s d?=?0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p?d?=?0.32–0.45).

Conclusions: In conclusion, HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX.  相似文献   
124.
Crowdsourcing platforms like Amazon’s Mechnical Turk and Crowdflower have been touted to be a cost-effective way to collect large amounts of behavioural data. Across four large-n studies, gambling-related behaviours, tendencies and traits among participants in these labour markets were examined. In Studies 1 and 2, both conducted on Crowdflower, problem gamblers (as measured by the benchmark Problem Gambling Severity Index) comprised 24.5% and 21.9% of participants, respectively. In Study 3, conducted on Mechanical Turk, problem gamblers comprised 9.0% of participants. In Study 4, a two-wave longitudinal study conducted on Crowdflower, problem gamblers comprised 13.5% of participants in wave one and 14.8% of participants in wave two. In Studies 2 and 3, strong convergent associations were demonstrated across various measures of problem gambling tendencies and general gambling involvement. Furthermore, it was demonstrated that gambling was associated with personality traits (impulsivity, sensation-seeking, self-control), risk attitudes, affect, and behavioural risk-taking consistent with previous research. In Study 4, it was demonstrated that measures of problem gambling have acceptable test-retest reliability. Online crowdsourcing platforms appear to offer access to samples with remarkably high proportions of problem gamblers. However, this characteristic means that such samples are not necessarily representative of gambling tendencies among more general populations.  相似文献   
125.
A significant challenge in fitting metamodels of large-scale simulations with sufficient accuracy is in the computational time required for rigorous statistical validation. This paper addresses the statistical computation issues associated with the Bootstrap and modified PRESS statistic, which yield key metrics for error measurements in metamodelling validation. Experimentation is performed on different programming languages, namely, MATLAB, R, and Python, and implemented on different computing architectures including traditional multicore personal computers and high-power clusters with parallel computing capabilities. This study yields insight into the effect that programming languages and computing architecture have on the computational time for simulation metamodel validation. The experimentation is performed across two scenarios with varying complexity.  相似文献   
126.
Early in the 30-year HIV/AIDS pandemic in Sub-Saharan Africa, epidemiological studies identified formal education attainment as a risk factor: educated Sub-Saharan Africans had a higher risk of contracting HIV/AIDS than their less educated peers. Later demographic research reported that by the mid-1990s the education effect had reversed, and education began to function as a social vaccine. Recent counter-evidence finds a curvilinear pattern, with the association between educational attainment and HIV/AIDS infection changing from positive to negative across the education gradient. To reconcile these inconsistent conclusions, a hypothesis is developed and tested that education at early stages functioned as a risk factor and later functioned (and continues to function) as a social vaccine. We reason that this shift in the direction of the education effect was concurrent with changes in the public health environment in SSA that early on heightened material benefits from educational attainment but later heightened cognitive benefits from schooling. Using the 2003/2004 Demographic Health Surveys from four Sub-Saharan African countries (Cameroon, Ghana, Kenya and Tanzania), we tested this hypothesis (differential effects of schooling) using non-linear regression analysis (probit), identifying the different public health periods and controlling for confounding factors. The results support the hypothesis that the education effect shifted historically in the HIV/AIDS pandemic in SSA as we hypothesized.  相似文献   
127.
Although Couple and Relationship Education (CRE) programs were intended to be preventive in nature, an emerging reality is that relationally distressed couples are attending programs. This has raised questions about both its general usefulness and what is known regarding predictors of change in CRE for distressed couples particularly. Previous work has identified dosage and duration as important moderators of changes, and there are myriad program contexts offered, highlighting the need to examine these among distressed couples. This study utilized a sample of community CRE participants and examined received dosage and program duration as predictors of change. Comparing results for distressed and non‐distressed participants, we found several group differences. Findings suggest that it is important to consider distress level and time spent in programs when placing participants. In addition, research should continue to examine these groups separately (or comparatively) to find out what works for whom.  相似文献   
128.
Fifty years ago, the Pulitzer Prize‐winning historian Richard Hofstadter published the seminal essay, “The Paranoid Style in American Politics.” In this and related works he examined the rhetoric animating the extreme right‐wing of the country's electorate. In this article I revisit Hofstadter's claims regarding the marginalization of the paranoid style and its connection to status‐based politics. A review of the most popular “pseudo‐conservative” commentators, survey data, the rise of the Tea Party, and the intransigence of the present day Republican Party suggests that a worldview that was once extreme has now become “mainstreme” within the political culture.  相似文献   
129.
The Revised Dyadic Adjustment Scale (RDAS; Busby, Crane, Larson, & Christensen, 1995) is a measure of couple relationship adjustment that is often used to differentiate between distressed and non‐distressed couples. While the measure currently allows for a determination of whether group mean scores change significantly across administrations, it lacks the ability to determine whether an individual's change in dyadic adjustment is clinically significant. This study addresses this limitation by establishing a cutoff of 47.31 and reliable change index of 11.58 for the RDAS by pooling data across multiple community and clinical samples. An individual whose score on the RDAS moves across the cutoff changes by 12 or more points can be classified as experiencing clinically significant change.  相似文献   
130.
Growth and internationalisation of the Chinese economy have reconfigured the global value chains of many commodities with important implications for industry and rural and regional development both in and outside China. This article analyses the chain for cashmere, all stages of which have gravitated to China, and the impacts on rural development, especially for herders in remote pastoral regions. Traditionally a high‐value product, cashmere has become increasingly generic and adulterated over the past decade. More formal and closer integration of Chinese actors into the global industry and re‐orienting policy from supply‐side intervention to the enforcement of standards would enhance the competitiveness of Chinese cashmere in international fibre markets.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号