全文获取类型
收费全文 | 88979篇 |
免费 | 1970篇 |
国内免费 | 13篇 |
专业分类
管理学 | 12121篇 |
民族学 | 547篇 |
人才学 | 26篇 |
人口学 | 6675篇 |
丛书文集 | 520篇 |
理论方法论 | 9328篇 |
综合类 | 2083篇 |
社会学 | 40913篇 |
统计学 | 18749篇 |
出版年
2023年 | 517篇 |
2021年 | 568篇 |
2020年 | 1515篇 |
2019年 | 2230篇 |
2018年 | 2032篇 |
2017年 | 3110篇 |
2016年 | 2345篇 |
2015年 | 2060篇 |
2014年 | 2642篇 |
2013年 | 18922篇 |
2012年 | 2234篇 |
2011年 | 2044篇 |
2010年 | 1925篇 |
2009年 | 2167篇 |
2008年 | 1996篇 |
2007年 | 1788篇 |
2006年 | 2033篇 |
2005年 | 2231篇 |
2004年 | 2116篇 |
2003年 | 1851篇 |
2002年 | 1949篇 |
2001年 | 1896篇 |
2000年 | 1680篇 |
1999年 | 1598篇 |
1998年 | 1456篇 |
1997年 | 1303篇 |
1996年 | 1267篇 |
1995年 | 1292篇 |
1994年 | 1266篇 |
1993年 | 1250篇 |
1992年 | 1205篇 |
1991年 | 1140篇 |
1990年 | 1114篇 |
1989年 | 967篇 |
1988年 | 1067篇 |
1987年 | 936篇 |
1986年 | 829篇 |
1985年 | 1007篇 |
1984年 | 1082篇 |
1983年 | 967篇 |
1982年 | 908篇 |
1981年 | 844篇 |
1980年 | 785篇 |
1979年 | 828篇 |
1978年 | 751篇 |
1977年 | 675篇 |
1976年 | 630篇 |
1975年 | 610篇 |
1974年 | 487篇 |
1973年 | 416篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
891.
Durand F. Jacobs Ph.D. 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》1988,4(1):27-37
A questionnaire was designed to test selected aspects of the author's General Theory of Addictions (Jacobs, 1982). Data were collected from groups of compulsive gamblers, alcoholics, and compulsive overeaters, and compared with the responses to the same questionnaire obtained from normative samples of adolescents and adults. The more inclusive term, compulsive gambler, has been used throughout, since the sample of gamblers in this study included an inpatient subgroup who had been diagnosed as pathological gamblers, as well as a subgroup of Gamblers Anonymous members who had not been clinically evaluated. Findings support the author's theoretical position that, when indulging, different kinds of addicts will tend to share a common set of dissociativelike experiences that differentiate them from nonaddicts. This has been termed a state of altered identity. 相似文献
892.
Litvin Y 《Vestnik statistiki (Moscow, Russia : 1949)》1988,(3):50-56
Methods that have been used or suggested to improve the accuracy of the U.S. census are reviewed. The author notes that self-completed questionnaires yield better results than those completed by census enumerators. The use of sample surveys carried out as part of the census process is described. 相似文献
893.
M. Ahsanullah 《Statistical Papers》1988,29(1):151-157
Suppose X1, X2, ..., Xm is a random sample of size m from a population with probability density function f(x), x>0 and let X1,m<...m,m be the corresponding order statistics. We assume m as an integer valued random variable with P(m=k)=p(1?p)k?1, k=1, 2, ... and 0 and n X1,n for fixed n characterizes the exponential distribution. In this paper we prove that under the assumption of monotone hazard rate the identical distribution of and (n?r+1) (Xr,n?Xr?1,n) for some fixed r and n with 1≤r≤n, n≥2, X0,n=0, characterizes the exponential distribution. Under the assumption of monotone hazard rate the conjecture of Kakosyan, Klebanov and Melamed follows from the above result with r=1. 相似文献
894.
In this paper the timing of maternity is estimated by a hazard model. The novel aspect of this paper is that it is shown that wages and total household labor income have a significant effect on the timing of maternity. Both the wage rate of the woman and the wage rate of the husband have a negative effect on the timing of maternity. Total household labor income increases the probability of having a child at an earlier age. Calculated elasticities show that the timing of maternity is relatively elastic with respect to wage rates. However, the elasticities of the decision whether or not to have children altogether are much smaller. Women working in the labor market delay the timing of maternity compared to non-participating women. Attending school has the same effect. Until the age of 28 the maternity hazard increases with age, after that it decreases.We benefited from comments on previous drafts by Siv Gustafsson, Joop Hartog, Peter Kee, Herriette Maassen van den Brink, Eddie Mekkelholt, Joop Odink, Hessel Oosterbeek, Hans van Ophem, Gusta Renes, Andre Voskamp, two anonymous referees, and the Managing Editor of this Journal. This paper is a revised version of a paper presented at the third annual meeting of the European Society for Population Economics, Paris, June 1989. The usual disclaimer applies. 相似文献
895.
A comparative study conducted in the Sudan illustrated both the potential of a nutrition education program for pregnant women and the many obstacles to creating more optimal maternal nutrition. Included in the study were 1200 women 18-34 years of age attending the Khartoum Province Model Clinic for a minimum of 5 prenatal visits. 83.3% were Muslims and 48.2% were illiterate. The 60 women who comprised the experimental group were exposed to individual nutrition counseling and home visits. Overall, 70% of subjects were anemic, 27% had malaria, and 18% were hookworm. The average weight gain during pregnancy was 4.5 kgs; 25.0% of controls and 20.0% of those in the experimental group gained 3.5-4.0 kgs, 18.3% of controls and 33.3% of experimental subjects gained 4.5-5.0 kgs, and 23.3% of controls and 30.0% of those in the experimental groups gained 5.5 kgs or more. 53.0% of controls and 61.7% of women exposed to nutrition education breastfed for at least 6 months, and 70% of women in the former group and 95% of those in the latter had enrolled their infants in an immunization program. A baseline nutrition questionnaire revealed widespread misinformation, especially a belief that pregnant women should reduce their food intake from 3 to 1-2 meals per day to prevent the fetus from growing too large and making labor difficult. Foods such as fermented sorghum products, fresh fish, and water melon were regarded as abortifacients and avoided, while hot pepper, sour milk, and cola sodas were considered nutritious. Consumption was self-reported to be poor for milk products by 25% of mothers, for meat by 16%, and for fruits and vegetables by 40% Although the educational intervention increased women's knowledge of basic nutrition, it had only a minimal effect on actual practice. This finding is assumed to reflect the widespread belief that men and their guests should be given preference in food allocation, poverty, and avoidance, on the basis of tradition, of many healthy foods. Since 72% of women reported ownership of a television, use if this medium is recommended for nutrition education. 相似文献
896.
Elective single mothers are adult, unmarried women who intentionally become mothers. This study utilized longitudinal data about 17 Caucasian, elective single mothers and their children to identify fathers' roles in these families, and to understand children's views of their fathers. These single mothers and their children resided for the first six years of the children's lives in father-absent households. By age six, most of the children had ghost fathers, whom they had never met or knew little about. The data suggest that the father often becomes a family secret, and that children may blame themselves for their fathers' absence. 相似文献
897.
Garry J. Smith Ph.D. 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》1992,8(4):331-349
A paradox currently exists regarding legal sports gambling in North America: various forms are flourishing in Nevada, Oregon, and several Canadian provinces, while at the same time the United States Congress is conducting hearings on two bills that would prohibit any new state-sponsored sports gambling initiatives. This study examines the issue of why some jurisdictions are enthusiastic about legal sports gambling while others strongly resist the concept. In reviewing these divergent viewpoints, a case study of the newfledged Canadian Sport Select gambling format is presented. This example is used to highly the perils and payoffs of a typical state-sponsored sports gambling scheme, with a view toward broadening our understanding of how they work and how they might be fairer to the public. 相似文献
898.
"This article revises the Coale-Trussell method for analyzing data from the World Fertility Survey by proposing and testing alternative log-linear and log-multiplicative models. The models, in one form or another, represent the structural constraint underlying the Coale-Trussell method on the variation in the age pattern of human fertility. With a Poisson distribution assumption for the number of births, several parameters of the models are simultaneously estimated via maximum likelihood. It is shown that the new approach can be adopted whenever fertility limitation is compared across multiple populations or subpopulations." 相似文献
899.
900.
The China Population information Centre (CPIC), set up in May 1980, is a national institution for population information research under the State Family Planning Commission. Its main functions are to 1) collect, process, and distribute and foreign materials on population and family planning; 2) collect, tabulate, and analyze population and family planning data; 3) keep abreast of new population and family planning developments within and outside the country; 4) edit and publish information materials; and 5) provide information users with diversified services. The CPIC has 8 operational units: 1) the Library, 2) the Statistics Division, 3) the 1st Information Research Division, 4) the 2nd Information Research Division, 5) the Editorial Division, 6) the Translation Division, 7) the Computer Division, and 8) the Technical Support Division. 相似文献