全文获取类型
收费全文 | 13644篇 |
免费 | 363篇 |
专业分类
各国政治 | 650篇 |
工人农民 | 534篇 |
世界政治 | 899篇 |
外交国际关系 | 466篇 |
法律 | 8750篇 |
中国政治 | 84篇 |
政治理论 | 2538篇 |
综合类 | 86篇 |
出版年
2020年 | 154篇 |
2019年 | 187篇 |
2018年 | 235篇 |
2017年 | 286篇 |
2016年 | 305篇 |
2015年 | 206篇 |
2014年 | 281篇 |
2013年 | 1369篇 |
2012年 | 305篇 |
2011年 | 333篇 |
2010年 | 299篇 |
2009年 | 281篇 |
2008年 | 354篇 |
2007年 | 385篇 |
2006年 | 384篇 |
2005年 | 317篇 |
2004年 | 312篇 |
2003年 | 349篇 |
2002年 | 288篇 |
2001年 | 554篇 |
2000年 | 501篇 |
1999年 | 409篇 |
1998年 | 177篇 |
1997年 | 141篇 |
1996年 | 143篇 |
1995年 | 129篇 |
1994年 | 148篇 |
1993年 | 128篇 |
1992年 | 238篇 |
1991年 | 291篇 |
1990年 | 276篇 |
1989年 | 287篇 |
1988年 | 270篇 |
1987年 | 302篇 |
1986年 | 274篇 |
1985年 | 279篇 |
1984年 | 235篇 |
1983年 | 249篇 |
1982年 | 164篇 |
1981年 | 172篇 |
1980年 | 130篇 |
1979年 | 206篇 |
1978年 | 152篇 |
1977年 | 134篇 |
1976年 | 109篇 |
1975年 | 123篇 |
1974年 | 137篇 |
1973年 | 130篇 |
1972年 | 94篇 |
1971年 | 102篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
He was only a little monkey, a very little one the first timeI saw him, not more than 9 inches tall; and when he died 3 yearslater, fully grown, he did not measure more than a foot anda half. 相似文献
32.
Joseph P. Lane 《The Journal of Technology Transfer》2003,28(3-4):333-354
The Rehabilitation Engineering Research Center on Technology Transfer (T2RERC) hosted a “State of the Science” conference in November, 2001. The conference reviewed technology transfer work within the field of assistive technology, and summarized related work in public, private and academic sectors. Invited speakers prepared papers on various topics concerning technology transfer, and related their findings to the field of assistive technology during the ensuing discussion sessions. This paper provides an overview of the material presented by the participants, and explores the implications of their findings for one particular field of application—assistive technology for people with disabilities. 相似文献
33.
Ross A. Thompson Mario J. Scalora Susan P. Limber Lynn Castrianno 《Family Court Review》1991,29(1):9-25
In recent years, legislators in all fifty states have given grandparents rights to petition for visitation privileges with grandchildren that can be enforced over parental objections. Grandparent visitation rights reflect an effort to protect meaningful relationships children enjoy with nonparental caregivers, enlist the assistance of extended family when the child's nuclear family is disrupted, and defend the interests of grandparents themselves. This psycholegal analysis explores the direct and indirect consequences of grandparent visitation statutes for family functioning. Statutory provisions are summarized, and the effects of these statutes are evaluated in light of what is known about the role of grandparents in child development, how courts evaluate children's "best interests" in grandparent visitation disputes, and how these statutes can alter family functioning in informal ways. The authors conclude that there are risks as well as benefits to children and families in grandparent visitation statutes, and suggest directions for procedural and statutory reform. 相似文献
34.
K. Minakata O. Suzuki Y. Ishikawa H. Seno M. Asano 《Forensic Science International Supplement Series》1991,50(2)
A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample. 相似文献
35.
DAVID P. FARRINGTON 《犯罪学》2003,41(2):221-225
The main aim of this paper is to advance knowledge and (especially) theories about developmental and life‐course criminology (DLC). First, I review the widely accepted DLC findings that all DLC theories have been designed to explain. Second, I review more contentious and unresolved empirical DLC issues that might present challenges to DLC theories. Third, I describe my own DLC theory and specify how it addresses key empirical and theoretical questions. Fourth, I summarize five important DLC theories, by Catalano and Hawkins, Sampson and Laub, Moffitt, LeBlanc, and Thornberry and Krohn. Fifth, I identify differences in assumptions and predictions between my theory and the other five theories. Finally, I recommend a detailed comparison of the key features of all DLC theories, of their answers to key empirical and theoretical questions, and of their predictions regarding key unresolved empirical DLC issues. 相似文献
36.
Esophageal and tracheal fistulas, which occur in 0.05% of medicolegal autopsies, were demonstrated in three cases by a postmortem radiographic technique using silicone rubber/lead oxide as a contrasting medium that vulcanizes at room temperature. In one 83-year-old male, a tracheoesophageal fistula was detected, which had developed after surgical repair of an esophageal rupture caused by a flexible fiberoptic endoscope. In a second case, carcinoma of the esophagus in a 78-year-old male had eroded the trachea and arcus of the aorta creating a fatal tracheoesophagoaortic fistula. In a third case, 55-year-old female developed a tracheobrachicephalic artery fistula as a result of an infiltrating cystic adenocarcinoma of the trachea, resulting in a fatal hemorrhage into the trachea. The results of this study indicate that diagnostic radiologic methods using a vulcanized contrasting medium are useful in supplementing normal dissection in autopsy cases with suspected fistulas of the esophagus or trachea. 相似文献
37.
Yahia H. Zoubir 《中东政策》2007,14(4):158-177
38.
We investigated the differences in the levels of carboxyhemoglobin (COHb), cyanide (HCN) and petroleum fuels (gasoline and kerosene) between left and right ventricular bloods from fire victims. COHb was slightly, and HCN and petroleum fuels were markedly higher levels in the left than those in the right. These effects were so called 'first pass phenomena' due to the circulation, diffusion and metabolization before the deaths of fire victims. 相似文献
39.
40.
D.S.T Lo T.C Chao S.E Ng-Ong Y.J Yao T.H Koh 《Forensic Science International Supplement Series》1997,90(3):626
Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%). 相似文献