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   8199篇
  免费   73篇
  国内免费   2篇
管理学   1277篇
民族学   24篇
人口学   720篇
丛书文集   24篇
理论方法论   695篇
综合类   92篇
社会学   4119篇
统计学   1323篇
  2020年   115篇
  2019年   137篇
  2018年   147篇
  2017年   178篇
  2016年   161篇
  2015年   108篇
  2014年   160篇
  2013年   1357篇
  2012年   180篇
  2011年   209篇
  2010年   159篇
  2009年   155篇
  2008年   192篇
  2007年   192篇
  2006年   202篇
  2005年   191篇
  2004年   167篇
  2003年   131篇
  2002年   148篇
  2001年   157篇
  2000年   178篇
  1999年   147篇
  1998年   143篇
  1997年   127篇
  1996年   135篇
  1995年   135篇
  1994年   143篇
  1993年   133篇
  1992年   145篇
  1991年   157篇
  1990年   173篇
  1989年   144篇
  1988年   162篇
  1987年   138篇
  1986年   133篇
  1985年   136篇
  1984年   148篇
  1983年   133篇
  1982年   101篇
  1981年   84篇
  1980年   93篇
  1979年   115篇
  1978年   92篇
  1977年   70篇
  1976年   84篇
  1975年   53篇
  1974年   78篇
  1973年   53篇
  1971年   44篇
  1970年   46篇
排序方式: 共有8274条查询结果,搜索用时 0 毫秒
21.
The concept of consumer “loyalty” (i.e., preference for a particular store or brand) is intriguing to marketing scholars and practitioners. Research in this area would be enhanced by the acceptance of an operational measure of consumer loyalty. Loyalty appears to be a tri-dimensional concept; per cent of budget, allocated to the store or brand, amount of switching, and number of alternatives explored have been used to measure loyalty. Consequently, the authors propose a “loyalty index” which combines these three measures. An empirical test of the proposed index showed that the index did discriminate among degrees of consumer loyalty, and was related to consumer psychological characteristics in a manner similar to that of the generally used single measures of consumer loyalty.  相似文献   
22.
Understanding contemporary urban landscapes requires multiple sets of spatially and temporally compatible data that can integrate historical land use patterns and disturbances to land cover. This paper presents three principal methods: (1) core analysis; (2) historic mapping; and (3) gradient analysis, to link spatial and temporal data for urban ecosystems and applies their use in the Baltimore-Chesapeake region. Paleoecological evidence derived from the geochronology of sediment cores provides data on long-term as well as recent changes in vegetative land cover. This information, combined with contemporary vegetation maps, provides a baseline for conducting trend analyses to evaluate urbanization of the landscape. A 200-year historical land use database created from historical maps, census data, and remotely sensed data provides a spatial framework for investigating human impacts on the region. A geographic information system (GIS) integrates core analyses with historic data on land use change to yield a comprehensive land use and land cover framework and rates of change. These data resources establish the regional foundation for investigating the ecological components of an urban ecosystem. Urban-rural gradient analyses and patch analyses are proposed as the most appropriate methods for studying the urban ecosystem as they link ecological and social patterns and processes for varying degrees of urbanization.  相似文献   
23.
24.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.  相似文献   
25.
Acceptable professional behaviour for social scientists has strayed from traditional ideals. Among other reasons, the predominantly middle-class world view of most social science professionals has contributed to a narrow perspective on social matters which often leaves prevailing societal assumptions unchallenged. The emerging vision of a socially responsible role for social scientists calls into question many currently accepted aspects of professionalism, and the paper argues for a change of emphasis within social science to accommodate this new vision within the fold of professional respectability.  相似文献   
26.
While there is a global shift towards smaller families, some groups maintain relatively high fertility rates. The 2013 New Zealand census data were used to investigate the nature of fertility between ethnicities in New Zealand. The NZ Deprivation Index 2013 was used as a measure of socioeconomic status to determine the relationships with fertility. The results mirror research outside of New Zealand in that socioeconomic status is inversely correlated to fertility. Using crude average fertility rates, sole-ethnicity Pasifika and Māori ethnic groups still have substantially higher fertility than sole-ethnicity Europeans and Asians ethnic groups, even when simultaneously accounting for age, socioeconomic status, education, and religious affiliation. Christians have more children than individuals reportedly without any religion, and fertility rates drop on average for mothers who have higher formal qualifications. Our findings suggest that cultural, or other ethnic-specific factors differentially affect fertility for Māori, Pasifika, New Zealand European, and Asians as aggregated ethnic categories, respectively.  相似文献   
27.
28.
29.
This article compares social assistance systems in Macao and Hong Kong. It finds that Macao delivers a higher level of social assistance benefits, whereas Hong Kong has a larger group of social assistance beneficiaries. The Hong Kong Government spends a larger amount on social assistance provision and imposes tougher controls on the recipients, compared to Macao. The results of the comparison indicate that Macao and Hong Kong differ markedly in the type of productivist welfare regime they belong and challenge the assertion that the two welfare systems form a distinct welfare model.  相似文献   
30.
This article describes the development and evaluation of an intergenerational service-learning course designed to promote social work gerocompetencies. Service-learning opportunities were structured into the course, including an optional evidence-based falls prevention program, for older adults, entitled A Matter of Balance (MOB). Significant differences between pre- and posttest scores on the Geriatric Social Work Competency Scale (GSWCS) were noted for students in the service learning course (n = 13). Once MOB was introduced as an independent variable, the MOB participants scored the highest mean posttest scores for 2 GSWCS domains: values, ethics, and theoretical perspectives; and intervention. The benefits of utilizing social work gerocompetencies to guide course objectives, content, and student outcomes are discussed.  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