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871.
Low concentrations of THC and 11-hydroxy-THC in serum samples are often claimed not to result from recent cannabis use. Prediction of time of exposure is difficult, especially if distinctive features of drug use could not be observed. Therefore, the aim of the study was to investigate the presence of THC and 11-hydroxy-THC in serum samples as well as to obtain preliminary data on the analyte profile for a time window of 24-48 hours after discontinuation of cannabis smoking. Serum samples from heavy (n = 12, > 1 joint/day), moderate (n = 11, < or = 1 joint/day) and light (n = 6, < 1 joint/week) smokers of cannabis were analyzed for THC, 11-hydroxy-THC and free THC-COOH by GC/MS as well as for glucuronidated THC-COOH by LC/MS-MS. The blood samples were collected 24-48 hours after abstaining from cannabis use. Additionally, 8 specimens were obtained from persons after discontinuation of the drug for more than 48 hours. During collection of the blood samples, distinctive effects due to drug use could not be observed. For heavy users of cannabis, THC was detectable in 8 samples, and in 5 cases both biologically active compounds, THC and 11-hydroxy-THC, were present (1.3-6.4 ng THC/mL serum, 0.5-2.4 ng 11-hydroxy-THC/mL serum). Among moderate users, in 1 sample 1.8 ng THC/mL serum and 1.3 ng 11-hydroxy-THC/mL serum were determined, and another sample was tested positive with low concentrations close to the limit of detection. In serum samples of light users both analytes could not be detected, indicating that in those persons a positive finding of THC and 11-hydroxy-THC may rather result from recent consumption than from cannabis use 1 or 2 days prior to blood sampling. The concentrations of THC-COOH and its glucuronide covered a wide range in all groups of cannabis users. However, there was a trend to higher concentrations in heavy users compared to moderate users, and the mean concentration was smaller in light smokers than in moderate smokers. Overall, the findings indicated that data from pharmacokinetic studies should be supplemented by data obtained from "real-life" samples. 相似文献
872.
The article summarises three fatalities after attacks by wild animals. The first case describes a 90-year-old woman who died as a result of pneumonia after a bear fell on her and caused multiple chest fractures. The second case deals with a 76-year-old woman who was hit in the middle face by the hoof of a camel and, thereafter, died of myocardial infarction. The third case describes a 27-year-old biologist who died from severe blunt trauma after an attack of a wild living elephant. The article gives a summary of typical injury patterns of selected wild animals and outlines potential reasons of death as a result of the injuries. 相似文献
873.
The article reports on findings after a suicide committed by being run over by the driving unit of an ICE train in a railway station. After recovering the body a fresh abrasion was found on the right upper abdomen with a minor laceration. Some hours later a circular abrasion mark and zones of contusion were discernible on the trunk. Whereas the integument was largely intact, the spine was severed and inner organs of the trunk were ruptured. 相似文献
874.
A method was developed to screen for pepper spray residue using instruments and methods other than those techniques commonly employed to analyze chemical residue (i.e.. gas chromatography mass spectrometry-GCMS or liquid chromatography mass spectrometry-LCMS). The method employed gas chromatography (GC), thin layer chromatography (TLC), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to screen for dried pepper spray stains. Pepper sprays from nine different manufacturers were investigated. Capsaicin and dihydrocapsaicin were identified and unique IR reflectance spectra are presented. An additional five compounds were presumptively found. Results showed that a particular stain could be characterized as a pepper-based stain. 相似文献
875.
Grinage BD 《Journal of forensic sciences》2003,48(4):861-868
This article discusses psychiatry's limited conceptualization of volitional capacity and its application to sexually violent predator laws by exploring two legal opinions critical to predator case law (Kansas v. Hendricks and Kansas v. Crane). The author reviewed pertinent psychiatric literature on impaired volition to identify potential contributions and limitations that psychiatry may offer the legal field. Assessment of the ego dystonic nature of impaired self-regulation, utilization of recent advances in self-assessment and laboratory evaluation of impulsive behavior, and dimensional categorization of a volitional capacity construct are recommended as an approach to the assessment and understanding of an inability to control concept. This paper concludes that elements of volition may be psychiatrically evaluated in a way that contributes to the Court's understanding of that capacity. However, further study is needed to operationally define volitional capacity and address issues of assessment validity and reliability. 相似文献
876.
Virtopsy-postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in a fatal scuba diving incident 总被引:7,自引:0,他引:7
Plattner T Thali MJ Yen K Sonnenschein M Stoupis C Vock P Zwygart-Brügger K Kilchör T Dirnhofer R 《Journal of forensic sciences》2003,48(6):1347-1355
The body of a 44-year-old scuba diver was examined using postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), and findings were verified by subsequent autopsy. The goal was to find out whether the important pathomorphological findings for the reconstruction of events and the identification of cause and manner of death could be identified using modem digital cross-sectioning techniques. The findings of a massive vital decompression with pulmonary barotrauma and lethal gas embolism were identified in the radiological images. MSCT and MRI were superior to autopsy in the demonstration of the extent and distribution of gas accumulation in intraparenchymal blood vessels of internal organs as well as in areas of the body inaccessible by standard autopsy. 相似文献
877.
LaPorte GM Wilson JD Mancke SA Payne JA Ramotowski RS Fortunato SL 《Journal of forensic sciences》2003,48(5):1163-1171
Thermal transfer printing refers to printing processes that utilize heat to produce an image by either physical or chemical means or by a combination of both. As the technology has improved and the supplies have become less expensive, the use of thermal printing in the personal and business markets has increased significantly. Specifically, dye diffusion thermal transfer and thermal mass transfer have become predominant in the production of counterfeit credit cards, drivers' licenses, and other types of documents produced on plastic media. Chemical analysis by means of thin layer chromatography (TLC) has proven to be useful in characterizing various types of inks (e.g., writing and inkjet inks). In this study, the authors examined 81 different samples that included a total of 54 printer samples (43 photographic prints on paper and eleven plastic card samples) and 27 printer ribbons. A new TLC method was developed and tested utilizing a solvent system (80% n-hexane, 3% methyl ethyl ketone, and 17% ethyl acetate) that is capable of producing excellent resolution. 相似文献
878.
879.
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
880.