全文获取类型
收费全文 | 5222篇 |
免费 | 173篇 |
专业分类
各国政治 | 255篇 |
工人农民 | 235篇 |
世界政治 | 368篇 |
外交国际关系 | 144篇 |
法律 | 3260篇 |
中国共产党 | 1篇 |
中国政治 | 32篇 |
政治理论 | 1068篇 |
综合类 | 32篇 |
出版年
2023年 | 44篇 |
2020年 | 68篇 |
2019年 | 80篇 |
2018年 | 102篇 |
2017年 | 120篇 |
2016年 | 124篇 |
2015年 | 107篇 |
2014年 | 105篇 |
2013年 | 548篇 |
2012年 | 146篇 |
2011年 | 131篇 |
2010年 | 121篇 |
2009年 | 123篇 |
2008年 | 156篇 |
2007年 | 144篇 |
2006年 | 135篇 |
2005年 | 136篇 |
2004年 | 142篇 |
2003年 | 132篇 |
2002年 | 121篇 |
2001年 | 186篇 |
2000年 | 183篇 |
1999年 | 132篇 |
1998年 | 73篇 |
1997年 | 63篇 |
1996年 | 47篇 |
1995年 | 61篇 |
1994年 | 51篇 |
1993年 | 50篇 |
1992年 | 92篇 |
1991年 | 89篇 |
1990年 | 111篇 |
1989年 | 92篇 |
1988年 | 84篇 |
1987年 | 88篇 |
1986年 | 105篇 |
1985年 | 116篇 |
1984年 | 79篇 |
1983年 | 80篇 |
1982年 | 52篇 |
1981年 | 47篇 |
1980年 | 48篇 |
1979年 | 49篇 |
1978年 | 55篇 |
1976年 | 35篇 |
1975年 | 46篇 |
1974年 | 62篇 |
1973年 | 55篇 |
1972年 | 42篇 |
1969年 | 41篇 |
排序方式: 共有5395条查询结果,搜索用时 10 毫秒
931.
932.
3'-Hydroxystanosolol detection in biological fluids at pg levels by gas chromatography/tandem mass spectrometry is described. Gas chromatography/high resolution mass spectrometry results can be confirmed with gas chromatography/tandem mass-spectrometry. 相似文献
933.
Papin F Clarot F Vicomte C Gaulier JM Daubin C Chapon F Vaz E Proust B 《Forensic science international》2007,166(2-3):85-90
Superwarfarin exposure is a growing health problem, described in many countries. The authors report a case of suspicious chlorophacinone poisoning with a problematic diagnosis. They review the literature and discuss particularities of anticoagulant rodenticide intoxication, as well as the apparent contradiction between anticoagulant intoxication and lethal thrombosis. 相似文献
934.
Lociciro S Hayoz P Esseiva P Dujourdy L Besacier F Margot P 《Forensic science international》2007,167(2-3):220-228
Optimisation and harmonisation of analytical and statistical methodology have been carried out between two forensic laboratories (Lausanne, CH and Lyon, F) in order to provide drug intelligence for cross-border cocaine seizures. The aim was to improve the gas chromatographic analysis of cocaine samples for profiling. Some important validation parameters were tested to verify the developed method and demonstrate its profiling capacity: the selectivity of the method with retention time reproducibility, the choice of a derivatisation agent improving the chromatography (MSTFA, BSA, TMSI and BSTFA+TMCS 1%), the cutting agents influence (matrix effect), the influence of the sample storage conditions and the sample quantity to weigh for analyses. Eight main alkaloids, which represent the sample signature, have been selected: ecgonine methyl ester, ecgonine, tropacocaine, benzoylecgonine, norcocaine, cis- and trans-cinnamoylcocaine and 3,4,5-trimethoxycocaine. Their stability in the solvent used (CHCl(3)/pyridine) was demonstrated. In order to reach the final objective, which is the comparison of samples seized and analyzed in two different laboratories, the harmonisation of the profiling method between the two laboratories had to be ensured and is the subject of ongoing research. 相似文献
935.
Strelova OIu Vozheva AB Slonimskaia EA Strelkova LF 《Sudebno-meditsinskaia ekspertiza》2007,50(3):31-33
The authors present a method of hingamine identification in non-biological substances (tablets, powder, syringes) and biological fluids (blood, urine). Isolation was made with chloroform in pH 10. Identification was conducted with thin-layer chromatography, gas chromatography/mass-spectrometry, high-performance liquid chromatography, spectrophotometry in UV region. The quantity was estimated with spectrophotometry in UV region, high-performance liquid chromatography and high-performance thin-layer chromatography. The results of the three methods are comparable. 相似文献
936.
Although narrative reviews have suggested that "youth psychopathy" is a strong predictor of future crime and violence, to date no quantitative summaries of this literature have been conducted. We meta-analyzed recidivism data for the Psychopathy Checklist measures across 21 non-overlapping samples of male and female juvenile offenders. After removing outliers, psychopathy was significantly associated with general and violent recidivism (r (w)'s of .24 and .25, respectively), but negligibly related to sexual recidivism in the few studies examining this low base rate outcome. Even after eliminating outliers, however, considerable heterogeneity was noted among the effects, with some of this variability being explained by the gender and ethnic composition of the samples. Effect sizes for the small number of female samples available for analysis were mostly small and nonsignificant, and psychopathy was a weaker predictor of violent recidivism among more ethnically heterogeneous samples. In relation to predicting both general and violent recidivism, psychopathy performed comparably to an instrument designed specifically to assess risk, the Youth Level of Service/Case Management Inventory (Hoge & Andrews, 2002). 相似文献
937.
Soares-Vieira JA Billerbeck AE Iwamura ES Zampieri RA Gattás GJ Munoz DR Hallak J Mendonca BB Lucon AM 《Journal of forensic sciences》2007,52(3):664-670
ABSTRACT: The incidence of rape has increased, especially in metropolitan areas, such as the city of São Paulo. In Brazil, studies about it have shown that the majority of this type of crime is committed by the relatives and persons close to the victim. This has made the crime more difficult to be denounced, as only 10% of the cases are reported to competent police authorities. Usually, cytological exams are carried out in sex crime investigations. The difficulty in showing the presence of spermatozoa is frequent, but it does not exclude the presence of male DNA. The absence of spermatozoa in material collected from rape victims can be due to several factors, including the fact that the agressor suffers from azoospermia. This condition can be the result of a successful vasectomy. As the majority of DNA in the ejaculation sample is from spermatozoa, there is much less DNA to be analyzed. This study presents the application of Y‐STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) in DNA analysis of sperm samples from 105 vasectomized men. The study demonstrated a great variation in DNA concentration. DNA extraction and amplification was possible in all sperm samples even in the absence of spermatozoa. The same profile was observed, for each individual, from DNA extracted from blood, pre‐ and postvasectomy semen samples. The use of markers specific for Y chromosome in sex crime cases, especially in the absence of spermatozoa, is very important, mainly because in most situations there is a small quantity of the agressor's DNA in the medium and a large quantity of the victim's DNA. 相似文献
938.
Methods to estimate adult age from observations of skeletal elements are not very accurate and motivate the development of better methods. In this article, we test recently published method based on the acetabulum and Bayesian inference, developed using Coimbra collection (Portugal). In this study, to evaluate its utility in other populations, this methodology was applied to 394 specimens from four different documented Western European collections. Four strategies of analysis to estimate age were outlined: (a) each series separately; (b) on Lisbon collection, taken as a reference Coimbra collection; (c) on Barcelona collection, taken as a reference both Portuguese collections; and (d) on London collection taken as reference the three Iberian collections combined. Results indicate that estimates are accurate (83-100%). As might be expected, the least accurate estimates were obtained when the most distant collection was used as a reference. Observations of the fused acetabulum can be used to make accurate estimates of age for adults of any age, with less accurate estimates when a more distant reference collection is used. 相似文献
939.
Carol K. Lee M.D. F.R.C.P.C. Sarah L. Lathrop D.V.M. Ph.D. 《Journal of forensic sciences》2010,55(1):100-103
Abstract: We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected. 相似文献
940.
Michał Kaliszan M.D. Ph.D. S.F.M. Ralph BouHaidar B.Sc. M.Sc. M.D. F.R.C.Path. 《Journal of forensic sciences》2010,55(3):822-825
Abstract: This is a case report of a 30‐year‐old man found dead in his flat lying on the floor with multiple stab wounds over the body, surrounded by an extensive volume of blood. Examination of the scene of death showed a secure flat, locked from inside. A blood‐stained knife was present close to the body and two unstained notes left on the sofa at the locus. A small plastic bag containing white powder (which following toxicological examinations appeared to be cocaine) and an almost full bottle of beer were present on a table. Autopsy revealed more than 40 stab wounds to neck, chest, and abdomen arranged in isolated groups within which the wounds showed similar directions and had a transverse orientation. Together with hesitation marks located on the neck and wrists these characteristics allowed to interpret this case as a suicide. 相似文献