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991.
Barroso M Gallardo E Margalho C Monsanto P Vieira DN 《Forensic science international》2006,162(1-3):121-125
A new and sensitive method to determine ticlopidine in whole human blood using proadifen as the internal standard (IS) is described. The analyte and IS were extracted by solid-phase extraction using Oasis HLB cartridges, and the extracts were analyzed by gas chromatography-electron impact ionisation-mass spectrometry (GC/EI-MS). Calibration curves were established daily in spiked blood samples using a non-linear calibration model, between 0.01 and 4.5 microg/mL. The correlation coefficients were higher than 0.995. Precision and accuracy fulfilled the internationally accepted criteria (coefficients of variation were less than 9%, and the measured concentrations were within +/-7% of the true value). Limits of detection and quantitation were respectively, 3 and 10 ng/mL. No interfering substances were detected by analysis of 10 blank blood samples of different origin. Mean recovery, calculated at three concentration levels, was 71%. Because of its simplicity and speed, the proposed method can be applied in the determination of this inhibitor of platelet aggregation in whole blood samples, and is suitable for application in toxicology routine analysis. 相似文献
992.
Castella V Dimo-Simonin N Brandt-Casadevall C Mangin P 《Forensic science international》2006,156(1):70-73
The potential to recover genetic profiles from evidence samples has substantially increased since robust and sensitive amplification kits are commercially available. Nevertheless, even the best amplification kits cannot succeed when the extracted DNA is of poor quality. In this study we compared the efficiency of silica (QIAamp DNA Mini Kit), Chelex and Phenol-Chloroform (PC) based protocols to recover DNA from different categories of samples (blood and saliva on cotton swabs, muscles, cigarette butts, saliva on foods and epidermal cells on clothes). The efficiency of the QIAamp system was improved when samples were treated with QIAshredder homogenizing columns. Overall, conventional Chelex or PC protocols allowed to recover conclusive SGM Plus profiles for 61% of the samples considered in this study. Contrastingly, 82% of them were successfully genotyped after being treated with a combination of QIAshredder and QIAamp systems. Our results further suggested that the QIAshredder/QIAamp protocol was particularly helpful to analyze evidence samples with few DNA and/or that were collected on substrates containing PCR inhibitors. 相似文献
993.
Analysis of artificially degraded DNA using STRs and SNPs--results of a collaborative European (EDNAP) exercise 总被引:4,自引:0,他引:4
Dixon LA Dobbins AE Pulker HK Butler JM Vallone PM Coble MD Parson W Berger B Grubwieser P Mogensen HS Morling N Nielsen K Sanchez JJ Petkovski E Carracedo A Sanchez-Diz P Ramos-Luis E Briōn M Irwin JA Just RS Loreille O Parsons TJ Syndercombe-Court D Schmitter H Stradmann-Bellinghausen B Bender K Gill P 《Forensic science international》2006,164(1):33-44
Recently, there has been much debate about what kinds of genetic markers should be implemented as new core loci that constitute national DNA databases. The choices lie between conventional STRs, ranging in size from 100 to 450 bp; mini-STRs, with amplicon sizes less than 200 bp; and single nucleotide polymorphisms (SNPs). There is general agreement by the European DNA Profiling Group (EDNAP) and the European Network of Forensic Science Institutes (ENFSI) that the reason to implement new markers is to increase the chance of amplifying highly degraded DNA rather than to increase the discriminating power of the current techniques. A collaborative study between nine European and US laboratories was organised under the auspices of EDNAP. Each laboratory was supplied with a SNP multiplex kit (Foren-SNPs) provided by the Forensic Science Service, two mini-STR kits provided by the National Institute of Standards and Technology (NIST) and a set of degraded DNA stains (blood and saliva). Laboratories tested all three multiplex kits, along with their own existing DNA profiling technique, on the same sets of degraded samples. Results were collated and analysed and, in general, mini-STR systems were shown to be the most effective. Accordingly, the EDNAP and ENFSI working groups have recommended that existing STR loci are reengineered to provide smaller amplicons, and the adoption of three new European core loci has been agreed. 相似文献
994.
995.
The use of annealing in forensic glass casework is reviewed. New data is presented that suggests a continuous approach to the interpretation of such data may be superior to the classification approach. Data are presented supporting the previously observed relationship between change in refractive index (RI) and the thickness of the glass pane. An examination of the possible assumption of independence between RI and change in RI is undertaken. 相似文献
996.
Kocsis RN Hayes AF 《International journal of offender therapy and comparative criminology》2004,48(2):149-160
This study investigated whether perceptions of criminal psychological profiles are influenced by the identity of the profile's author. Police officers were given a profile they were told was written by either a professional profiler or by an unspecified author. When judged in relation to the actual perpetrator of the crime, police officers tended to perceive greater accuracy in a profile when it was labeled as authored by a professional profiler independent of the actual content of the profile. But officers' judgments of the usefulness of the profile were not affected by knowledge of who wrote the profile. Explanations for this result focus on the ambiguous nature of criminal profiles and how this ambiguity enhances the likelihood that beliefs about the validity of profiling can color perceptions of the content of the profile. 相似文献
997.
An alleged assault was reported by a 42-year-old female, with initial medical examination revealing an apparent bite mark on the right buttock. Odontological examination, including visual assessment, full history and photographs showed that the injury did not meet the class characteristics of a human bite. Subsequent digital overlay production showed that the injury pattern was consistent with a corrugated bottle top. This case highlights the need for careful assessment of injuries alleged to be caused by human teeth. 相似文献
998.
999.
Gunshot wounds of skin and long cortical bones inflicted by the special intelligence knife (NRS and NRS-2: special silent cartridges SP-3 and SP-4) from different distances were examined. Stereomicroscopy, emission spectral analysis, contact-diffusion method and regression- step-by-step analysis were made use of within the case study. A lack of mechanical, thermal or chemical impact from firing gas and of fire soot as well as presence of particles of rubber, copper and sealing varnish, i.e. the most informative shot products, were found to be the main distinctive features in the said wounds. The data obtained can be used in the differential diagnosis of a type and model of the used gun. 相似文献
1000.
Mandal GN 《William and Mary law review》2004,45(5):2167-2259
The regulation of genetically modified products pursuant to statutes enacted decades prior to the advent of biotechnology has created a regulatory system that is passive rather than proactive about risks, has difficulty adapting to biotechnology advances, and is highly fractured and inefficient--transgenic plants and animals are governed by at least twelve different statutes and five different agencies or services. The deficiencies resulting from this piecemeal approach to regulation unnecessarily expose society and the environment to adverse risks of biotechnology and introduce numerous inefficiencies into the regulatory system. These risks and inefficiencies include gaps in regulation, duplicative and inconsistent regulation, unnecessary increases in the cost of and delay in the development and commercialization of new biotechnology products. These deficiencies also increase the risk of further unnecessary biotechnology scares, which may cause public overreaction against biotechnology products, preventing the maximization of social welfare. With science and society poised to soar from first-generation biotechnology (focused on crops modified for agricultural benefit), to next-generation developments (including transgenic fish, insects, and livestock, and pharmaceutical-producing and industrial compound-producing plants and animals), it is necessary to establish a comprehensive, efficient, and scientifically rigorous regulatory system. This Article details how to achieve such a result through fixing the deficiencies in, and risks created by, the current regulatory structure. Ignoring many details, the solutions can be summarized in two categories. First, statutory and regulatory gaps that are identified must be closed with new legislation and regulation. Second, regulation of genetically modified products must be shifted from a haphazard model based on statutes not intended to cover biotechnology to a system based upon agency expertise in handling particular types of risks. 相似文献