全文获取类型
收费全文 | 9444篇 |
免费 | 322篇 |
专业分类
各国政治 | 632篇 |
工人农民 | 414篇 |
世界政治 | 741篇 |
外交国际关系 | 395篇 |
法律 | 5419篇 |
中国共产党 | 2篇 |
中国政治 | 144篇 |
政治理论 | 1926篇 |
综合类 | 93篇 |
出版年
2020年 | 125篇 |
2019年 | 151篇 |
2018年 | 216篇 |
2017年 | 232篇 |
2016年 | 236篇 |
2015年 | 206篇 |
2014年 | 210篇 |
2013年 | 1164篇 |
2012年 | 250篇 |
2011年 | 326篇 |
2010年 | 236篇 |
2009年 | 254篇 |
2008年 | 271篇 |
2007年 | 248篇 |
2006年 | 239篇 |
2005年 | 213篇 |
2004年 | 231篇 |
2003年 | 252篇 |
2002年 | 173篇 |
2001年 | 358篇 |
2000年 | 333篇 |
1999年 | 300篇 |
1998年 | 150篇 |
1997年 | 106篇 |
1996年 | 122篇 |
1995年 | 106篇 |
1994年 | 109篇 |
1993年 | 108篇 |
1992年 | 164篇 |
1991年 | 160篇 |
1990年 | 154篇 |
1989年 | 142篇 |
1988年 | 168篇 |
1987年 | 159篇 |
1986年 | 160篇 |
1985年 | 148篇 |
1984年 | 148篇 |
1983年 | 154篇 |
1982年 | 93篇 |
1981年 | 69篇 |
1980年 | 83篇 |
1979年 | 99篇 |
1978年 | 81篇 |
1977年 | 67篇 |
1976年 | 71篇 |
1975年 | 59篇 |
1973年 | 49篇 |
1972年 | 53篇 |
1971年 | 54篇 |
1969年 | 54篇 |
排序方式: 共有9766条查询结果,搜索用时 15 毫秒
201.
202.
Rizk IA Stokes CS Nelson MR 《Studies in Comparative International Development (SCID)》1982,17(2):74-86
Child mortality was analyzed in relation to 3 dimensions of reproductive behavior: birth intervals, additional children desired, and contraceptive use. Study data were drawn from a 1978 survey conducted in 2 predominantly rural governorates, Beheira and Kafr El-Sheikh, in lower Egypt. Within each governorate, 2 districts were selected on the basis of their distance from the capital of the governorate, agricultural output by major crops, percent of the population urban, infant mortality rate, and crude birthrate. Within each of the 4 districts, villages were randomly drawn from 3 strata: villages lacking any governmental services; villages with limited services (health center or primary school); and villages served by a combined unit center providing integrated services. A random sample of household heads was selected from household registration records of the provision office of each district. 1200 interviews were obtained from 685 households. Restriction of the sample to women with 1 or more live births, and the elimination of 13 cases with incomplete or inaccurate information, yielded 1010 cases for analysis. The basic measure of actual fertility was birth intervals. For the total sample and within each age category, cumulative fertility is higher the greater the number of child deaths. The data demonstrate a strong relationship between child mortality experience and cumulative fertility. The problem lies in interpreting such results. With some exceptions, birth intervals increased as expected with increasing parity. Women without child death experience displayed longer birth intervals than women who had not lost a child. With the single exception of the 7th parity women, all differences were statistically significant. The data fail to eliminate potential biological influences on subsequent fertility. With biological influences adequately controlled, no behavioral differences remained. Women who experienced child mortality desired greater numbers of additional children than women without child death experience. 19% of respondents were ever users of contraception, with women of low parity the least likely ever to have used contraception. 相似文献
203.
204.
205.
206.
207.
208.
J C Anthony 《Journal of health politics, policy and law》1979,4(1):87-108
The Controlled Substances Act (CSA) is the prevailing "drug abuse" control statute in the United States. Its manifest objective is to prevent or reduce drug use's "substantial and detrimental effect on the health and general welfare of the American people." Evaluating CSA's effectiveness in 1975, a Domestic Council Task Force reported in a White Paper to President Gerald Ford that its control measures do "reduce abuse of dangerous drugs." The Task Force's evidence was based upon a before-and-after analysis of the frequency of "drug abuse episodes" reported to the nation's Drug Abuse Warning Network (DAWN). This research note challenges the conclusion of the Domestic Council Task Force, subjecting the DAWN evidence to more rigorous scrutiny, and concluding that we do not presently have adequate materials to assess whether CSA meets its health objectives. The context of this conclusion is that of drug control, but its implications apply to health policy and health policy evaluation in general. 相似文献
209.
A maze of record-keeping, disclosure, and privacy statutes and regulations, with accompanying case law, have created a boom in privacy law. Employers find themselves caught in this rising tide, torn between the often conflicting requirements. The issue of access to employee files--by employees, government, and unions--is one of the most difficult issues in this complicated situation. This article discusses recent developments in the field and aims to help readers thread their way through the maze of contradictions and pitfalls confronting employers. 相似文献
210.
The results of a study of the polymorphism of the sixth component of human complement by means of isoelectric focusing in polyacrylamide gels with subsequent C-dependent lysis in an agarose overlay containing C6 deficient rabbit serum are reported. The allele frequencies obtained (C6A = 0.613, C6B = 0.379, C6R = 0.008) are in good agreement with those previously published. The mode of inheritance in 47 families with 173 offspring as well as 26 mother-child combinations is in agreement with a formal genetical model: "C6A, C6B, C6A1 and C6B1 at an autosomal locus". The inclusion of this system into a blood group expertise in Germany can be recommended. 相似文献