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171.
Geographic and technological R&;D spillovers within the triad: micro evidence from US patents 总被引:1,自引:0,他引:1
This paper aims at assessing the magnitude of R&D spillover effects on large international R&D companies’ productivity growth.
In particular, we investigate the extent to which R&D spillover effects are intensified by both geographic and technological
proximities between spillover generating and receiving firms. We also control for the firm’s ability to identify, assimilate
and absorb the external knowledge stock. The results estimated by means of panel data econometric methods (system GMM) indicate
a positive and significant impact of both types of R&D spillovers and of absorptive capacity on productivity performance.
相似文献
Michele Cincera (Corresponding author)Email: |
172.
173.
Pujol-Luz JR Francez PA Ururahy-Rodrigues A Constantino R 《Journal of forensic sciences》2008,53(2):476-478
The black soldier-fly (Hermetia illucens) is a generalist detritivore which is commonly present in corpses in later stages of decomposition and may be useful in forensic entomology. This paper describes the estimation of the postmortem interval (PMI) based on the life cycle of the black soldier-fly in a case in northern Brazil. A male child was abducted from his home and 42 days later his corpse was found in an advanced stage of decay. Two black soldier-fly larvae were found associated with the body. The larvae emerged as adults after 25-26 days. Considering the development cycle of H. illucens, the date of oviposition was estimated as 24-25 days after abduction. Since H. illucens usually (but not always) colonizes corpses in more advanced stages of decay, this estimate is consistent with the hypothesis that the child was killed immediately after abduction. 相似文献
174.
Dedouit F Bindel S Gainza D Blanc A Joffre F Rougé D Telmon N 《Journal of forensic sciences》2008,53(2):288-295
Age determination is a major field of interest in physical and forensic anthropology. Among the different methods based on macroscopic skeletal study, the Iscan method, which analyzes the sternal end of the right fourth rib, is one of the most reliable. We applied the Iscan method to two- and three-dimensional multislice computed tomography (MSCT) reconstructions of the sternal end of the right fourth rib on 39 ribs. The intra-observer variability on MSCT reconstructions was good (gamma coefficient equal to 0.86; value of the Krippendorff's alpha reliability equal to 0.79); inter-observer variability on MSCT reconstructions was also good (gamma coefficient ranging from 0.82 to 0.88; value of the Krippendorff's alpha reliability ranging from 0.78 to 0.86). We demonstrated excellent agreement between the results of analysis of bone samples and those of the two- and three-dimensional images, in particular regarding bone projections, morphology of the pit and of its rim. The accuracy of age estimation did not significantly differ between the Iscan method applied to dry bones and the same method applied to MSCT images. Determination of the Krippendorff's alpha reliability coefficient for the inter-error method confirmed the agreement between phase estimations obtained with the two methods (ranging from 0.55 to 0.71). The real civil age was comprised in 21 cases out of 36 for assessment performed on dry bones and in 23 cases out of 36 on MSCT reconstructions, which represented 58.3% and 63.9%, respectively. Use of MSCT reconstructions in forensic anthropology offers many advantages: no bone preparation, no damage to bone material, and the possibility of application to living individuals. 相似文献
175.
Dedouit F Guilbeau-Frugier C Capuani C Sévely A Joffre F Rougé D Rousseau H Telmon N 《Journal of forensic sciences》2008,53(6):1424-1429
A 17-month-old male infant died at home. The infant's right arm was immobilized because of a humeral fracture 1 month earlier. The circumstances of death appeared unclear to the police investigators and a medicolegal autopsy was carried out. External examination revealed diffuse ecchymoses of varying color. Postmortem imaging was performed prior to autopsy (X-rays, multislice computed tomography [MSCT], and focused brain magnetic resonance imaging [MRI]). These investigations revealed four rib fractures of varying ages, one of which was posterior. Cerebral and pericerebral traumatic lesions were also diagnosed: bilateral subdural hematomas, intraventricular, meningeal, and interpedoncular hemorrhages. In the abdomen, fresh blood was visible within the anterior abdominal wall and the mesenteric root. Autopsy and microscopic study confirmed these lesions. This case report illustrates the valuable assistance rendered by MSCT and MRI to diagnose abuse when a child has died in unclear circumstances. 相似文献
176.
With a large number of unidentified skeletal remains found in South Africa, the development of population specific osteometric standards is imperative. Forensic anthropologists need to have access to a variety of techniques to establish accurate demographic profiles from complete, fragmentary and/or commingled remains. No research has been done on the forearm of African samples, even though these bones have been shown to exhibit sexual dimorphism. The purpose of this paper is to develop discriminant function formulae to determine sex from the radius and ulna in a South African population. The sample consisted of 200 male and 200 female skeletons from the Pretoria Bone (University of Pretoria) and Raymond A. Dart (Witwatersrand University) collections. Sixteen standard anthropometric measurements were taken from the radius (9) and ulna (7) and subjected to stepwise and direct discriminant function analysis. Distal breadth, minimum mid-shaft diameter and maximum head diameter were the best discriminators of sex for the radius, while minimum mid-shaft diameter and olecranon breadth were selected for the ulna. Classification accuracy for the forearm ranged from 76 to 86%. The radius and ulna can be considered moderate discriminators for determining sex in a South African group. However, it is advised that these formulae are used in conjunction with additional methods to determine sex. 相似文献
177.
Amedeo Argentiero Michele Bagella Francesco Busato 《European Journal of Law and Economics》2008,26(3):341-359
This paper implements a methodology that exploits firms and households’ optimality conditions to measure money laundering
for the Italian economy. This approach, first implemented by Ingram et al. (J Monet Econ 40:435–436, 1997) to the household
production sector, and by Busato et al. (Using theory for measurement: an analysis of the behaviour of underground economy
working paper, Aarhus University, 2006) for measuring the underground economy, allows to generate high frequency time-series
for money laundering using a theoretical two-sector dynamic general equilibrium model calibrated over the sample 1981:01–2001:04.
The analysis of the generated series suggests two main results. First, money laundering accounts for approximately 12 percent
of aggregate GDP; second, money laundering is more volatile than aggregate GDP and it is negatively correlated with it.
相似文献
Francesco BusatoEmail: Email: |
178.
Ururahy-Rodrigues A Rafael JA Wanderley RF Marques H Pujol-Luz JR 《Forensic science international》2008,182(1-3):e19-e22
Taphonomy is the study of many variables involving decomposition, preservation, dispersal, erosion, burial or exposition of dead organisms. Forensic Taphonomy examines how biotic or abiotic variables can change evidences in legal investigations. Many insects are closely associated with decomposition processes. The scavenger dung-beetle, Coprophanaeus lancifer (Linnaeus, 1767), may be important biotaphonomically in the decomposition process of carcasses. Man-size pig carcasses were used as models to examine the decomposition process in the Adolpho Ducke Forest Reserve in central Amazonia. The scavenger dung-beetle has great potential in decomposition and production of post-mortem injuries, including dismemberment and the removal of soil beneath the carcass thereby causing a change in its position. 相似文献
179.
The purpose of this study was to examine substance use patterns among a sample of incarcerated males who report engaging in levels of intimate violence, as well as identifying similarities and differences in demographic, economic status, mental health, criminal justice involvement, relationships, and treatment factors for three groups of incarcerated males - those who report perpetrating low intimate violence, those who report perpetrating moderate intimate violence, and those who report perpetrating extreme intimate violence the year preceding their current incarceration. Findings indicated that low intimate violence group's perpetration consisted almost exclusively of emotional abuse. Moderately intimate violent males and extremely intimate violent males, however, report not only high rates of emotional abuse but physical abuse as well. The distinction between moderate and extremely violent groups was substantial. Findings also indicated that perpetrators at different levels of violence in this study did not vary significantly in age, employment history, marital status, or race. However, the three groups showed significant differences in three main areas: (1) cocaine and alcohol use patterns, (2) stranger violence perpetration and victimization experiences, and (3) emotional discomfort. Implications for substance abuse and mental health treatment interventions and for future research are discussed. 相似文献
180.