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501.
Pseudo-Stab Wounds: Putrefactive Dehiscence of Remote Surgical Incisions Masquerading as Stab Wounds
James R. Gill M.D. ; Dennis P. Cavalli RPA-C M.P.H. ; Susan F. Ely M.D. M.P.H.T.M. 《Journal of forensic sciences》2009,54(5):1152-1154
Abstract: Artifacts due to decomposition can be mistaken for antemortem injury leading to an incorrect suspicion of foul play. We describe an instance of postmortem wound dehiscence that mimicked antemortem stab wounds. A man with a history of colon cancer and substance abuse was found dead. There were advanced putrefactive changes and multiple defects of the anterior torso that resembled stab wounds. Subsequent investigation revealed that 11 months earlier, he had a laparoscopic-assisted colon resection that involved surgical incisions corresponding in location and size to the above defects. Putrefactive gases may cause bloating of the body. This distension may cause recent and remote healed incisions to dehisce. Correlation of these "defects" at autopsy with the antemortem clinical history is crucial in determining their etiology. 相似文献
502.
Dobberstein RC Huppertz J von Wurmb-Schwark N Ritz-Timme S 《Forensic science international》2008,179(2-3):181-191
Postmortem teeth are the most stable structures, and can be used to gain different information (age estimation, genetic data). Over long postmortem intervals (PMI), degradation processes may alter the molecular integrity and thus affect the reliability of applied molecular methods. Whereas some knowledge on the degradation of biomolecules in bone during the PMI exists, data for teeth are lacking. In particular, the impact of degradation processes in dentine on age estimation based on aspartic acid racemization (AAR) cannot be estimated yet. Hence, the molecular stability of both collagen and DNA was analyzed systematically, and their impact on the reliability of age estimation based on AAR and genetic analyses was checked. Two hundred and ten human and 59 porcine teeth were heated (90 degrees C in water) to simulate collagen and DNA diagenesis; 14 naturally aged teeth (PMI: 3 days to 1700 years) were analyzed comparatively. Peptide patterns of cyanogen bromide (CNBr)-cleaved collagen were employed as a new approach to check the collagen integrity. In the same samples, collagen yields, amino acid compositions, AAR in different protein fractions, and DNA integrity were analyzed. In heated human and porcine teeth the collagen content declined during the heating experiment. The amino acid composition in human samples was collagen-like until 12 days of heating. In naturally aged teeth, the collagen yielded from 9.5 to 15%, and no discrepancy of amino acid composition to that of modern collagen was observed. Electrophoresis of CNBr-peptides showed an altered pattern in experimentally degraded samples from day 10 on; naturally aged collagen displayed the typical collagen pattern. AAR increased in all protein fractions with increasing duration of the heating experiment; naturally aged samples displayed a slow accumulation of AAR. DNA degraded progressively, and after 32 h of heat exposure no more DNA was detectable, whereas the amplification of nuclear and mitochondrial DNA was successful up to 48 h. STR typing was reliable up to 16 h, and sex determination up to 40 h of heat exposure. In naturally aged samples of DNA quality, yield and typing success did not correlate with PMI. The data highlight a remarkable stability of collagen dental proteins. Within relevant forensic periods a postmortem rise of AAR under normal conditions is negligible, and analyses of dental DNA has a high chance to be successful. However, after large PMI and/or extreme postmortem conditions age estimation based on AAR and genetic analyses lose their reliability. 相似文献
503.
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505.
Dennis Y. Wang Chien-Wei Chang Lori K. Hennessy 《Forensic Science International: Genetics Supplement Series》2009,2(1):115-116
The establishment of offender DNA databases is critical to future crime prevention. Many countries have established databases or are in the process of passing database legislation. With new legislation the number of samples that will be collected could begin to exceed the testing capacity of many labs leading to backlogs.Two bottlenecks in the workflow that can contribute to a backlog of samples are DNA purification and PCR cycling time. The average purification time is approximately 2 h and the average cycling time of current STR kits is approximately 3 h. To address the second problem we investigated alternative DNA enzymes to decrease PCR cycling time. It was necessary to balance the increase in time to result against the need to address factors which can impact interpretation of a DNA profile such as: generation of stutter products, non-template addition, intra-locus balance, accuracy, and species specificity.Initial feasibility studies demonstrate that alternative enzymes can decrease PCR cycling time. The data show that this assay can increase throughput, providing results in less than 2 h. However, decreasing PCR cycling time will have an affect on multiplex STR performance. 相似文献
506.
Vitreous Fluid and/or Urine Glucose Concentrations in 1335 Civil Aviation Accident Pilot Fatalities*
Arvind K. Chaturvedi Ph.D. Sabra R. Botch M.S. M.A. Dennis V. Canfield Ph.D. Estrella M. Forster Ph.D. 《Journal of forensic sciences》2009,54(3):715-720
Abstract: During aviation accident investigations, vitreous fluid and urine samples from pilot fatalities are analyzed for glucose and blood for hemoglobin A1c (HbA1c) to monitor diabetic pilots and to discover other pilots with undiagnosed/unreported diabetes. The prevalence of elevated glucose concentrations in fatally injured pilots was evaluated by searching the Civil Aerospace Medical Institute’s Toxicology Database for the period 1998–2005. Out of 1335 pilots involving 363 vitreous fluid, 365 urine, and 607 vitreous fluid and urine analyses, 43 pilots had elevated glucose in vitreous fluid (>125 mg/dL) and/or in urine (>100 mg/dL). Of the 20 pilots whose blood samples were analyzed, nine had >6% HbA1c—four were known diabetics, and five were unknown diabetics. Urinary glucose levels were elevated in all 13 known hyperglycemic pilots. A considerable number of pilots (30 of 43) had elevated glucose and HbA1c (5 of 20), suggesting undiagnosed/unreported diabetic conditions. 相似文献
507.
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
508.
Robert J. Gatchel Nancy D. Kishino Dennis E. Minotti 《Psychological injury and law》2010,3(3):212-219
The present article discusses the three major components of behavior that are used for assessing pain—self-report, overt behavior/function, and physical indices. Issues concerning the reliable operational definitions of these three behavioral referents of pain are reviewed, as well as the fact that a high degree of concordance or precise overlap among the three cannot be automatically assumed. The best biopsychosocial assessment approved to be used when discordance occurs—a stepwise approach to assessment—is then presented. Finally, in addition to the often complex interactions among the three behavioral referents of pain, what makes this assessment area even more complicated is that there may also be complex interactions among the construct of pain and the two related constructs of impairment and disability. These potential complexities are also discussed. 相似文献
509.
Policy Sciences - In an era of strong global competition, national, state, and localgovernments are vying to attract and retain investment by international firmsby increasing the range and value of... 相似文献
510.
This article surveys the empirical literature that has attempted to measure the effects of competition in defense procurement. Its focus is on the conceptual underpinnings of the empirical models rather than on the technical aspects of the estimation procedures. While the empirical studies provide some valuable insight, the studies are flawed because they assume an implicit model of the procurement environment that is inconsistent with reasonable economic behavior on the part of defense contractors and seems to be contradicted by the evidence. In general, the predictive power of the empirical models is also limited by a program-by-program estimation approach in which only a handful of data points are available to estimate two or more parameters. These empirical models could be improved by the use of structural models that assume reasonable economic behavior and provide a theoretical basis for cross-program analyses. 相似文献