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   34327篇
  免费   794篇
  国内免费   136篇
教育   24517篇
科学研究   2950篇
各国文化   420篇
体育   3660篇
综合类   26篇
文化理论   274篇
信息传播   3410篇
  2021年   321篇
  2020年   521篇
  2019年   786篇
  2018年   1045篇
  2017年   1013篇
  2016年   971篇
  2015年   684篇
  2014年   868篇
  2013年   6402篇
  2012年   774篇
  2011年   841篇
  2010年   692篇
  2009年   727篇
  2008年   756篇
  2007年   668篇
  2006年   660篇
  2005年   572篇
  2004年   801篇
  2003年   659篇
  2002年   662篇
  2001年   831篇
  2000年   712篇
  1999年   600篇
  1998年   374篇
  1997年   346篇
  1996年   413篇
  1995年   361篇
  1994年   354篇
  1993年   302篇
  1992年   491篇
  1991年   474篇
  1990年   477篇
  1989年   488篇
  1988年   429篇
  1987年   423篇
  1986年   422篇
  1985年   478篇
  1984年   388篇
  1983年   404篇
  1982年   332篇
  1981年   314篇
  1980年   333篇
  1979年   453篇
  1978年   332篇
  1977年   299篇
  1976年   271篇
  1975年   237篇
  1974年   240篇
  1973年   226篇
  1971年   227篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Youth on the street: Abuse and neglect in the eighties   总被引:2,自引:0,他引:2  
This paper discusses the findings of a study of runaways and homeless youth who were interviewed on the street the last week of every month on five week nights from late afternoon until 2 a.m. over a period of one year. The data derived from 489 interviews provided some interesting insights. Two distinct groups emerged from the analysis, generating a tentative hypothesis that the true "runners" tend to leave their homes with the intention of not returning and thus their runs are extended; the second group, designated "in and outers," use the run as a temporary coping mechanism. Their runs tend to be impulsive and of short duration. The study found that runaways (in particular the runners) are at great risk of being drawn into illegal activities. Major factors affecting this risk are distance from home and length of time on the run. A significant proportion of the youth interviewed had run from substitute care arrangements, and a disturbing implication emerging from the research is that adolescents in our society suffer from systemic abuse and neglect. One outcome of this piece of research was the opening of a safe house for early runners in January 1987. The operation of the house includes careful compilation of data to further advance understanding of the runaway population and its needs.  相似文献   
982.
Resilience in child maltreatment victims: a conceptual exploration   总被引:1,自引:0,他引:1  
While many child maltreatment victims suffer serious negative emotional sequelae, others do surprisingly well. Resilience in children is a relative concept which can change over time and is affected by environment and genetics. Resilience is fostered by protective factors which ameliorate or alter a child's response to the hazards of maltreatment that usually predispose to maladaptive outcome. Personal characteristics or skills that may foster resilience include (1) rapid responsivity to danger; (2) precocious maturity; (3) dissociation of affect; (4) information seeking; (5) formation and utilization of relationships for survival; (6) positive projective anticipation; (7) decisive risk taking; (8) the conviction of being loved; (9) idealization of an aggressor's competence; (10) cognitive restructuring of painful experiences; (11) altruism; and (12) optimism and hope. There are also generic life circumstances, such as having access to good health, educational, and social welfare services, that foster resilience in children regardless of the specific nature of the stressor. Additionally, there may be abuse-specific protective factors in the environment. Examples might include the quick and full acknowledgment of an offender regarding abuse, or timeliness and permanence of legal actions affecting a child's custody. The life stories of three well-known survivors of various forms of child maltreatment illustrate how protective factors contribute to resilience. A caution is noted regarding how personal characteristics developed for survival may become maladaptive if overused and/or not given up when the stressor no longer exists. Characterological problems are most likely to develop when a child's life circumstances fail to change and the environment never becomes secure.  相似文献   
983.
984.
Despite long-established roots in experimental psychophysiology and psychosomatic medicine, behavioral medicine and health psychology have only recently emerged as recognized, highly visible disciplines within medicine and the behavioral sciences. The rapid development of these fields has resulted partly from important scientific advances in the biomedical and behavioral sciences and partly from changing societal concerns and values. The latter include a greater preoccupation with individual self-expression and self-fulfillment, a decline in respect for authority per se, and an increased skepticism about social institutions. Coupled with these changes has been an increasing desire to take responsibility for one's own life and, in matters of health, of one's own body. The ways in which scientific advances and social changes have influenced the shape of contemporary behavioral medicine and health psychology are explored with the aid of two illustrations: the growth of a developmental perspective in behavioral medicine and health psychology; and work and health, including the effects of job stress and unemployment. Finally, the author stresses the need for a greater sense of community and concern for others, if we are to succeed in creating a growth-enhancing, health-producing climate for society as a whole and for each of us as individuals.  相似文献   
985.
"The U.S. Bureau of the Census has published on CD-ROM format data for the smallest geographic reporting levels....Providing access to the maps that define the reporting areas used by the Bureau within a county is one aspect of service that is unique to census files STF1A, STF1B, and STF3A. The paper illustrates the way these reporting levels are defined in the Tract/BNA Maps and Block Maps. The steps taken by one library to develop a link between a geographic area of interest to a patron and the areas defined on these maps are described. These steps include preserving and housing the maps in a way that makes them easy to use and preparing an index to the information contained on the maps using dBASE registered trademark software and information taken from STF1A using Extract software."  相似文献   
986.
Background:In a sprint cross-country(XC)ski competition,the difference in recovery times separating the first and the second semi-final(SF)heats from the final(F)may affect performance.The aim of the current study was to compare the effects of longer vs.shorter recovery periods prescribed between the 3 knock-out races of a simulated sprint XC ski competition involving a prologue(P),quarter-final(QF),SF,and F.Methods:Eleven well-trained XC ski athletes completed 2 simulated sprint XC ski competitions on a treadmill involving 4×883-m roller-ski bouts at a 4°incline using the gear 3 ski-skating sub-technique.The first 3 bouts were completed at a fixed speed(PFIX,QFFIX,and SFFIX)corresponding to~96%of each individual’s previously determined maximal effort.The final bout was performed as a self-paced sprint time trial(FSTT).Test conditions differed by the time durations prescribed between the QFFIX,SFFIX,and FSTT,which simulated real-world XC ski competition conditions using maximum(MAX-REC)or minimum(MIN-REC)recovery periods.Results:The FSTT was completed 5.4±5.5 s faster(p=0.009)during MAX-REC(179.2±18.1 s)compared to MIN-REC(184.6±20.0 s),and this was linked to a significantly higher power output(p=0.010)and total metabolic rate(p=0.009).The pre FSTT blood lactate(BLa)concentration was significantly lower during MAX-REC compared to MIN-REC(2.5±0.8 mmol/L vs.3.6±1.6 mmol/L,respectively;p=0.027),and the pre-to-post FSTT increase in BLa was greater(8.8±2.1 mmol/L vs.7.1±2.3 mmol/L,respectively;p=0.024).No other differences for MAX-REC vs.MIN-REC reached significance(p>0.05).Conclusion:Performance in a group of well-trained XC skiers is negatively affected when recovery times between sprint heats are minimized which,in competition conditions,would occur when selecting the last QF heat.This result is combined with a higher pre-race BLa concentration and a reduced rise in BLa concentration under shorter recovery conditions.These findings may help inform decision making when XC skiers are faced with selecting a QF heat within a sprint competition.  相似文献   
987.
Administrators of color in predominantly White institutions (PWI) navigate from dual positions of privilege and marginalization. Within PWIs, administrators of color experience marginalization in terms of their racial/ethnic makeup. Specifically focusing on the administrative level, 95.8% of executive provosts and 86.2% of deans of academic colleges are White. At the faculty level, nearly 10% of full professors are people of color. However, even with such exclusionary practices, 87.7% of chief diversity officers are racial minorities. The current study seeks to understand how highly educated administrators of color work for diversity, inclusion, and equity initiatives while navigating from their dual positions of marginalization and privilege. Using the theoretical lenses of co-cultural theory, dominant group theory, and intersectionality, the study seeks to understand how privilege and marginalization ebbs and flows depending on particular contexts. Findings indicate that optimizing privilege through co-cultural praxis and impeding through mentoring are two common strategies used by administrators of color.  相似文献   
988.
According to its proponents, animal-free animal food products, such as cultured meat and synthetic cow’s milk, have the potential to overcome various environmental, health and ethical challenges that have emerged around global animal product consumption and the industrial agriculture that is needed to support it. Apart from the myriad of technical problems making animal-free food products, critics have pointed out the blurry ontological status of the food and the ethical challenges therein, and have questioned the veracity of the various promissory narratives being produced. This paper considers animal-free food from a social studies of economies and markets (SSEM) perspective. As a market that currently mostly only exists in potential, an SSEM perspective can reveal the various social and material relations that comprise the (bio)capital formation that will underpin any market-to-be, an aspect of markets that are often invisible once markets are up and running. Moreover, this perspective details the intimate role markets have in establishing the ethical and ontological aspects of animal-free foods in a political economy shaped by neoliberalisation and financialisation.  相似文献   
989.
990.
English-Spanish cognates are an important subset of words in both the English and Spanish languages. Cognates are words that possess identical or nearly identical spellings and meanings in both languages as a result of being derived from Latin and Greek. Of major importance is the fact that many of the more than 20,000 cognates in English are academic vocabulary words, terms essential for comprehending school texts.

?The Pura Belpré Children's Book Award has been given since 1996 to outstanding children's and young adult literature that represents, affirms, and celebrates the Latino cultural experience. The books are judged for their literary and artistic quality.

?There are many English-Spanish cognates in each of the Pura Belpré picture books. The purpose of this article is to introduce the Pura Belpré Cognate Database, which lists all of the English-Spanish cognates for each of the children's picture books that have won the award or have been designated as honor books. Ideas for vocabulary, spelling, and morphology lessons or mini-lessons are also presented.  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