全文获取类型
收费全文 | 7748篇 |
免费 | 249篇 |
专业分类
各国政治 | 617篇 |
工人农民 | 214篇 |
世界政治 | 735篇 |
外交国际关系 | 437篇 |
法律 | 3716篇 |
中国政治 | 57篇 |
政治理论 | 2134篇 |
综合类 | 87篇 |
出版年
2023年 | 36篇 |
2020年 | 120篇 |
2019年 | 142篇 |
2018年 | 192篇 |
2017年 | 224篇 |
2016年 | 239篇 |
2015年 | 151篇 |
2014年 | 189篇 |
2013年 | 1161篇 |
2012年 | 205篇 |
2011年 | 235篇 |
2010年 | 192篇 |
2009年 | 187篇 |
2008年 | 244篇 |
2007年 | 304篇 |
2006年 | 241篇 |
2005年 | 232篇 |
2004年 | 239篇 |
2003年 | 246篇 |
2002年 | 227篇 |
2001年 | 167篇 |
2000年 | 164篇 |
1999年 | 139篇 |
1998年 | 139篇 |
1997年 | 113篇 |
1996年 | 126篇 |
1995年 | 93篇 |
1994年 | 85篇 |
1993年 | 100篇 |
1992年 | 101篇 |
1991年 | 123篇 |
1990年 | 115篇 |
1989年 | 107篇 |
1988年 | 111篇 |
1987年 | 110篇 |
1986年 | 120篇 |
1985年 | 78篇 |
1984年 | 88篇 |
1983年 | 87篇 |
1982年 | 78篇 |
1981年 | 69篇 |
1980年 | 58篇 |
1979年 | 61篇 |
1978年 | 64篇 |
1977年 | 60篇 |
1975年 | 37篇 |
1974年 | 37篇 |
1973年 | 44篇 |
1970年 | 35篇 |
1968年 | 35篇 |
排序方式: 共有7997条查询结果,搜索用时 31 毫秒
901.
902.
John H. Laub 《Journal of criminal justice》1981,9(6):419-430
A review of recent criminological literature suggests that different systems of social control operate across the urban-rural dimension. Specifically, it is expected that victims in urban areas will report crimes to the police at a higher rate than victims in surburban and rural areas. Moreover, it is anticipated that urban, suburban, and rural victims will have different reasons for not reporting the crime. In this paper these issues are examined empirically using the National Crime Survey victimization data. These data show that, contrary to theoretical expectations, the extent of victim reporting does not vary across the urban-rural dimension for the crimes of rape, robbery, assault, and personal larceny. Characteristics of the offense, notably seriousness, are shown to be more important in victim reporting than the extent of urbanization. In addition, these data indicate that victim residence in conjunction with type of crime and victim-offender relationship has an influence on the reasons selected by victims for not reporting the crime to the police. 相似文献
903.
Digoxin was determined in postmortem serum samples from 100 patients who died suddenly of cardiac disease. Twenty patients had digoxin levels below the therapeutic range. Twenty-one patients had normal values within the therapeutic range (1.2-2.5 nmol/l). In ten cases there was probably an overdosage. Another 15 patients had markedly elevated levels. No digoxin concentration was found (below 0.5 nmol/l) in 34 patients. The importance of determination of digoxin levels both by the clinician and the pathologist is stressed as well as the necessity of using a correct sampling technique at autopsy. 相似文献
904.
905.
906.
907.
908.
Many programs and projects have been remiss at looking at outcome variables such as recidivistic child abuse and neglect. Presented here are program evaluation data which examine recidivism data over 5 years across more than 700 families. Families receiving services from Project 12-Ways, a multifaceted in-home ecobehavioral approach, were compared with families indicated in the same region who received child protective services other than those offered by Project 12-Ways. Families who receive services from Project 12-Ways are less likely to reinjure or neglect their children again. 相似文献
909.
910.
Supravital electrical excitability of muscles 总被引:1,自引:0,他引:1
A new method of postmortem electrical stimulation of muscles, measuring the force of the reaction against time, is presented. Preliminary investigations have yielded the following results: The maximum force of reaction in response to a definitive stimulation, measured by a sensitive force transducer, decreases in proportion to the post mortem interval. Using this method, the mechanical reactions of muscles by electrical stimulation can be demonstrated over a much longer postmortem period as these movements are visible. The duration of postmortem reaction of different muscles seems to be much more uniform than was previously assumed. Occasionally, reactions of the M. orbicularis oculi can be seen for the longest time. The basal muscular tonus changes relative to time. The time course of a single force reaction also changes relative to the postmortal interval: the reaction becomes slower. It has been theoretically established that measurement of influencing factors such as temperature and pH in the tested muscle will enable the time of death to be more precisely estimated. 相似文献