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991.
This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries.  相似文献   
992.
Zaleplon, a sedative-hypnotic, was identified in the blood of a subject arrested for impaired driving. Symptoms reported were those of central nervous system (CNS) depression. The zaleplon concentration was determined to be 0.13 microg/mL. Symptoms included slow movements and reactions, poor coordination, and lack of balance. Although no quantitative relationship between blood concentrations and degree of driving impairment is currently possible, it is reasonable to conclude that because of its specific activity as a sedative-hypnotic, blood concentrations consistent with doses exceeding therapeutic concentrations of zaleplon have the potential to cause impairment of psychomotor function, and would impair a person's level of consciousness and driving ability.  相似文献   
993.
994.
A 29-year old female with a history of depression was found dead in a hotel room. The death scene investigation found empty pill bottles and an empty liter bottle of wine. Metaxalone, a centrally acting muscle relaxant, along with citalopram, ethanol, and chlorpheniramine were identified in the postmortem samples and quantitated by gas chromatography-mass spectrometry. The concentration of metaxalone in femoral vein blood was 39 mg/L. The heart blood concentration was 54 mg/L. Femoral vein blood concentrations of citalopram and chlorpheniramine were 0.77 mg/L and 0.04 mg/L, respectively. Ethanol levels were 0.13 g/dL in vitreous and 0.08 g/dL in heart blood. Other tissue samples were also analyzed. The authors consider the metaxalone concentrations toxic and potentially fatal. The citalopram concentrations were lower than those reported in fatal cases for this drug alone. Death was ascribed to polydrug abuse/overdose with metaxalone a major contributor. This represents the first reported case to our knowledge in which a metaxalone overdose significantly contributed to death.  相似文献   
995.
This study was conducted in an attempt to develop a metallographic method for the investigation of pipe bombings. Three common pipe materials, ASTM A53 steel, AISI 304L stainless steel, and 6061-T6 aluminum, were shock-loaded using five high explosives and three propellants. The explosives used were ANFO, Composition C4, C6 detasheet, nitroglycerine-based dynamite, and flake TNT. The propellants used were FFFFg black powder. Red Dot smokeless powder, and Turbo Fuel A. The post-blast microstructure, hardness, and, in the case of 304L, transformed martensite content were examined for each test. The damage done to the microstructure was found to increase with increasing detonation velocity of the explosives and increase in pressure generated by the shock-metal interaction. Material hardness and, in the case of 304L, martensite content showed a sharp increase followed by a plateau as the shock pressure and detonation velocity increased.  相似文献   
996.
A total of 743 lethal outcomes of thromboembolytic complications of trauma, diseases and certain pathological conditions as observed in 1999-2001 and in the three quarters of 2002 were studied. The undertaken analysis confirmed two factors provoking the pathological thrombosis, i.e. 1. Pathological changes observed in the surface vascular wall preconditioned by mechanical damages, atherosclerotic process and aging; and 2. A slower blood flow due to an impaired blood circulation, a forced positioning and to hypodynamics. While deciding on a possibility of a direct cause-effect relation between past traumas, surgeries, poisonings and death of thromboembolism of the pulmonary arteries (TEPA), such relation can be mentioned only on rare occasions. It is more often the case that an indirect, mediated relationship is found, when TERA evolves due to an unfavorable combination of risk factors, i.e. a forced immobility, changing coagulated blood system, impaired blood vessels etc.  相似文献   
997.
A possibility was studied to use the plaster copies of skulls in the forensic medical identification of personality by applying the craniofacial method. No dependence was found between the plaster casts and the moulding types. Differences between the same craniometric sizes in the skull and in its cast are of an incidental nature. Such incidental deviation is related with an accuracy of determining the localization of craniometric points and with an instrumental precision of measuring devices. The necessity is substantiated that, while making a craniofacial examination, it is necessary to mark all anthropometric points in the skull cast, with the original being a control. The use of a plaster skull cast is possible in those cases, when the burial of the remains must be done in full.  相似文献   
998.
This article provides a new maximum-likelihood estimator forselection models with dichotomous dependent variables when identicalfactors affect the selection equation and the equation of interest.Such situations arise naturally in game-theoretic models whereselection is typically nonrandom and identical explanatory variablesinfluence all decisions under investigation. When identicalexplanatory variables influence selection and a subsequent outcomeof interest, the commonly used Heckman-type estimators identifyfrom distributional assumptions about the residuals alone. Whenits own identifying assumption is reasonable, the new estimatorallows the researcher to avoid the painful choice between identifyingfrom distributional assumptions alone and adding a theoreticallyunjustified variable to the selection equation in a mistakenattempt to "boost" identification. The article uses Monte Carlomethods to compare the small-sample properties of the estimatorwith those of the Heckman-type estimator and ordinary probit.  相似文献   
999.
Disability has high societal and personal costs. Various disparate federal and state programs attempt to address the economic and social needs of people with disabilities. Presumably workplace injuries and accidents are an important source of disability. Yet separate public policies and research literatures have evolved for these two social problems--disability and workplace injuries--despite their relatedness. This article seeks to document the overlap between these two phenomena in estimating the proportion of the disabled population whose disability was caused by workplace injury, accident, or illness using the Health and Retirement Study of 1992. The results point toward the need for initiatives to reduce disability that focus on work-related causes, which are a common pathway to disability, and that may result in substantial savings in federal programs.  相似文献   
1000.
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