全文获取类型
收费全文 | 5968篇 |
免费 | 196篇 |
专业分类
各国政治 | 235篇 |
工人农民 | 365篇 |
世界政治 | 425篇 |
外交国际关系 | 238篇 |
法律 | 3779篇 |
中国政治 | 38篇 |
政治理论 | 1051篇 |
综合类 | 33篇 |
出版年
2023年 | 54篇 |
2021年 | 39篇 |
2020年 | 90篇 |
2019年 | 133篇 |
2018年 | 166篇 |
2017年 | 185篇 |
2016年 | 196篇 |
2015年 | 115篇 |
2014年 | 140篇 |
2013年 | 582篇 |
2012年 | 175篇 |
2011年 | 193篇 |
2010年 | 130篇 |
2009年 | 173篇 |
2008年 | 176篇 |
2007年 | 186篇 |
2006年 | 190篇 |
2005年 | 122篇 |
2004年 | 124篇 |
2003年 | 128篇 |
2002年 | 101篇 |
2001年 | 225篇 |
2000年 | 218篇 |
1999年 | 163篇 |
1998年 | 71篇 |
1997年 | 70篇 |
1996年 | 58篇 |
1995年 | 61篇 |
1994年 | 65篇 |
1993年 | 61篇 |
1992年 | 125篇 |
1991年 | 110篇 |
1990年 | 135篇 |
1989年 | 123篇 |
1988年 | 138篇 |
1987年 | 137篇 |
1986年 | 105篇 |
1985年 | 113篇 |
1984年 | 87篇 |
1983年 | 79篇 |
1982年 | 56篇 |
1981年 | 48篇 |
1980年 | 45篇 |
1979年 | 53篇 |
1978年 | 37篇 |
1976年 | 32篇 |
1975年 | 28篇 |
1974年 | 45篇 |
1973年 | 29篇 |
1970年 | 29篇 |
排序方式: 共有6164条查询结果,搜索用时 15 毫秒
901.
Crystal Munger M.S.F.S. Kris M. Gates B.S. M.A.T. Christopher Hamburg B.S. 《Journal of forensic sciences》2014,59(5):1351-1357
Refractive indices of seven double‐paned vehicle windshields were measured to assess the variation across the pane of glass and to evaluate collection techniques for known glass standards by comparing false negative rates. Measurements were made using a Foster and Freeman GRIM3 instrument, and a minimum of 240 measurements were made per pane. The mean SD of the windshields was 0.00004. It was further determined that collecting a known sample from two different sections of a shattered windshield gave the lowest rate of false negatives when using ± 2 standard deviations to estimate the RI variation of the known glass. Additionally, refractive indices often were highest in the center of the windshield and decreased toward the left and right edges; in approximately half the sample set, the two panes of a single windshield were differentiated by one or more properties. 相似文献
902.
Marc L. Sprouse B.S. Nicole R. Phillips Ph.D. Mark F. Kavlick B.S. Rhonda K. Roby Ph.D. M.P.H. 《Journal of forensic sciences》2014,59(4):1049-1056
The quantity of mitochondrial DNA (mtDNA) template added for amplification and subsequent dye terminator reactions is critical for obtaining quality sequence data. Validation of a human mtDNA real‐time quantitative PCR (qPCR) assay demonstrated its high degree of reproducibility and precision as well as an extremely sensitive threshold of detection (0.0001 pg/μL or approximately six human mtDNA copies/μL). A study of 35 nonprobative bone and teeth evidence samples revealed that 20 pg of mtDNA template is recommended for successful HV1 and HV2 sequence analysis; however, as little as 0.013 pg can generate a full mtDNA profile when using enhanced amplification reactions. The assay can also detect PCR inhibition and is useful for identifying samples that may benefit from re‐purification. Overall, the assay is an excellent method to quantify mtDNA and is useful for determining the best analytical approach for successful sequencing. 相似文献
903.
The case of a 22‐year‐old male Caucasian driver is presented. He was involved in a traffic collision. At the roadside, he displayed blank stare and mellow speech with a barely audible voice. A DRE found low body temperature, rigid muscle tone, normal pulse, lack of horizontal and vertical gaze nystagmus, nonconvergence of the eyes, dilated pupil size, and normal Pupillary reaction to light. A standard toxicology DUID protocol was performed on the driver's whole blood including ELISA and GC‐MS drug screens with negative results. Additional drug screening was undertaken for bath salts and synthetic cannabinoid receptor agonists by LC‐MS/MS by a commercial laboratory and identified the synthetic cannabinoid receptor agonist XLR‐11 in the driver's blood. XLR‐11 was subsequently quantified at 1.34 ng/mL. This is the first documented case involving a driver operating a motor vehicle under the influence of the synthetic cannabinoid receptor agonist XLR‐11. 相似文献
904.
905.
Sarah Becker 《Critical Criminology》2014,22(2):199-218
Renewed interest in communities as spaces for criminal opportunity has generated numerous studies of neighborhood social dynamics and crime. Most of this research is rooted in social disorganization theory, which examines neighborhood structural characteristics that facilitate effective social control. While many studies tout the benefits of community-based controls, the potential externalities of these efforts remain underexplored. In the modern neoliberal context, where policing strategies stress community involvement and often focus on vaguely-defined problems like “quality of life” or “incivilities” and where police have considerable enforcement discretion, the unintended consequences of community-based controls are important to document. I use the ethnographic case study of Gardner Village to explore the potential collateral consequences of one form of collective social control: new parochialism. Applying a critical lens to the social disorganization literature, I argue that when embedded in particular structural contexts, new parochialism contributes to the reproduction of inequality and undermines community-building processes. 相似文献
906.
907.
Sonali Das Rangan Gupta Patrick T. Kanda Monique Reid Christian K. Tipoy Mulatu F. Zerihun 《Economic Change and Restructuring》2014,47(1):41-62
The real interest rate is a very important variable in the transmission of monetary policy. It features in vast majority of financial and macroeconomic models. Though the theoretical importance of the real interest rate has generated a sizable literature that examines its long-run properties, surprisingly, there does not exist any study that delves into this issue for South Africa. Given this, using quarterly data (1960:Q2-2010:Q4) for South Africa, our paper endeavors to analyze the long-run properties of the ex post real rate by using tests of unit root, cointegration, fractional integration and structural breaks. In addition, we also analyze whether monetary shocks contribute to fluctuations in the real interest rate based on test of structural breaks of the rate of inflation, as well as, Bayesian change point analysis. Based on the tests conducted, we conclude that the South African EPPR can be best viewed as a very persistent but ultimately mean-reverting process. Also, the persistence in the real interest rate can be tentatively considered as a monetary phenomenon. 相似文献
908.
The strong correlation between measures of personal and peer deviance occurs with near “law‐like” regularity. Yet, as with other manifestations of peer similarity (often referred to as homophily), the mechanisms generating this relationship are widely debated. Specific to the deviance literature, most studies have failed to examine, simultaneously, the degree to which similarity is the consequence of multiple causes. The current study addresses this gap by using longitudinal network data for 1,151 individuals from the Netherlands Institute for the Study of Crime and Law Enforcement (NSCR) School Project. Structural equation modeling is used to address these issues by adapting Jussim and Osgood's ( 1989 ) model of deviant attitudes in dyadic pairs to the current data. Across two separate behavioral domains (substance use and property offending), the results provide strong support for the prediction that individuals project their own deviant tendencies inaccurately onto their peers. Conversely, the results provide little or no support for the predictions that respondents accurately perceive their peers’ deviance or that their perceptions of peer deviance influence their own behavior. Implications for understanding the role of peer behavior in the etiology of adolescent deviance are discussed. 相似文献
909.
DANIEL T. RAGAN 《犯罪学》2014,52(3):488-513
The association between delinquent peers and delinquent behavior is among the most consistent findings in the criminological literature, and several recent studies have raised the standards for determining the nature and extent of peer influence. Despite these advances, however, key questions about how deviant behavior is socially transmitted remain unresolved. In particular, much of the research examining peer influence has been limited to peer behavior, despite a rich literature supporting the salience of beliefs, such as expectations and moral approval, in shaping behaviors. In the current study, I model the peer influence and selection processes with longitudinal social network analysis to reexamine the contributions of peer beliefs and behaviors to adolescent drinking. I find evidence that beliefs related to peer drinking have both a direct and an indirect impact on behavior and play an important role in the friendship selection process. These results highlight the importance of understanding how peers influence deviant behavior and suggest that peer beliefs are an important part of this relationship. 相似文献
910.
Carmen P. McLean Sarah Herrick Morris Phoebe Conklin Nuwan Jayawickreme Edna B. Foa 《Journal of family violence》2014,29(5):559-566
This study examined the relationship between the characteristics of childhood sexual abuse (CSA) and the severity of consequent posttraumatic stress disorder (PTSD), depression, suicidal ideation, and substance use in a sample of 83 female adolescents aged 13–18 years seeking treatment for PTSD. Nearly two-thirds of the sample (60.7 %, n?=?51) reported the perpetrator of the CSA was a relative. A large portion (40.5 %, n?=?34) of the sample reported being victimized once, while almost a quarter of the sample reported chronic victimization (23.8 %, n?=?20). PTSD and depression scores were in the clinical range, whereas reported levels of suicidal ideation and substance use were low. The frequency of victimizations was associated with suicidal ideation. Contrary to expectation, CSA characteristics including trauma type, perpetrator relationship, and duration of abuse were unrelated to PTSD severity, depressive symptoms, or substance abuse. 相似文献