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961.
Nuclear DNA was extracted from human telogen hairs from 60 individuals. Six to nine hairs from each individual were individually extracted. The amount of DNA recovered from each individual varied greatly, and most samples yielded a quantity of 550 pg or less per hair. A selective extraction buffer was used to remove epithelial cell DNA and the amount of exogenous DNA was determined. DNA was also quantified by real time PCR using three different sized amplicons targeting an Alu sequence. The results were used to determine the state of degradation of the extracted DNA. Different quantities of sample (<100 pg, 100-500 pg, >500 pg) were amplified with the Miniplex kits to determine the minimum DNA template required for successful amplification. DNA recovered from hair showed degradation; however, partial profiles were obtained for those samples containing at least 60 pg using MiniSTRs. 相似文献
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Bradley K. Tom M.S. Mikko T. Koskinen Ph.D. Melody Dayton M.S. Anna‐Maria Mattila M.S. Eric Johnston M.S. Dennis Fantin Ph.D. Sue DeNise Ph.D. Theresa Spear M.S. David Glenn Smith Ph.D. Jessica Satkoski Ph.D. Bruce Budowle Ph.D. Sree Kanthaswamy Ph.D. 《Journal of forensic sciences》2010,55(3):597-604
Abstract: Despite the popularity of dogs in US households, canine DNA evidence remains largely untapped in forensic investigations partially because of the absence of well‐defined forensic short tandem repeats (STRs), lack of standardized and validated PCR protocols, STR reagent kits, and poorly developed nomenclature. A nomenclature system was established based on internationally recognized recommendations for human forensic STRs for a recently developed canine STR reagent kit. Representative alleles were sequenced from each of the 18 STRs and the sex‐typing marker included in the kit. This study also reflects on the impact of point mutations, insertions, and deletions within and outside the STR core repeat structures. An understanding of the STRs’ sequence and repeat structures will enable development of a robust and reliable allele nomenclature and improve the accuracy and precision of allele fragment sizing in canine forensic profiling. The expected allele sizes have been calculated, and their repeat stuctures defined based on sequence information. 相似文献
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Recently, much attention has been given to benzodiazepines and gamma-hydroxybutyric acid (GHB) related compounds owing to their alleged widespread use as date-rape drugs. Toxicologists would greatly benefit from a screening method that allows for the simultaneous detection of both groups of substances. A new capillary electrophoresis (CE) method has been developed in the micellar mode to accomplish this separation in under 16 min using a sodium dodecyl sulfate (SDS)/sodium tetraborate/boric acid buffer with an acetonitrile organic modifier. Optimization of SDS and organic modifier concentration, along with pH, were performed on a set of standards containing eight benzodiazepines, GHB, gamma-butyrolactone, and the internal standard, sulfanilic acid. The method was shown to have a detection limit of less than 2 microg/ml for five out of eight benzodiazepines with a linear range of 2.5-100 microg/ml. The detection limit for GHB was 32 mg/ml with a linear range to 2500 microg/ml. This method was applied to the rapid analysis of spiked beverages. GHB spiked beverages were monitored after using a series of simple dilutions to determine the effects of time on the drug analysis. Possible interfering peaks from drugs of abuse and artifacts from a variety of different drink combinations were also studied in detail. A one-step liquid-liquid extraction was the only necessary sample pretreatment. 相似文献
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Snitching and the Code of the Street 总被引:1,自引:0,他引:1
Rosenfeld Richard; Jacobs Bruce A.; Wright Richard 《British Journal of Criminology》2003,43(2):291-309
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The affirmation of radical left political ideology was examined among a total of 159 religious apostates and 272 religious believers who were undergraduates at five Chicago area colleges (study I) and seven western North Carolina colleges (study II). Contrary to current assumptions, apostates were not converts to radical ideology in any significant proportion, although they were clearly more disenchanted with their society and more sharply critical of its basic institutions. Apostates seem to take an ideological stance of critical disengagement rather than substitute conversion. Implications are discussed in the context of Erikson's theory interrelating ideological commitment and identity formation in youth.Study I was part of a doctoral dissertation by the first author at The University of Chicago.Received his B.A. from Stanford University, M.A. from Brandeis University, and Ph.D. from the Committee on Human Development, University of Chicago (1971). Main research interest is in the developmental psychology of religious faith and doubt.Received his B.A. and M.A. from the University of Chicago and his Ph.D. from the Committee on Human Development, University of Chicago. Main research interest is in the psychology of professions. 相似文献