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331.
Many different molecular typing methods have been reported to complement routine serological ABO blood typing in forensics. However, these ABO genotyping methods are often time-consuming and call for an initial DNA isolation step that requires the use of expensive kits or reagents. We report here a rapid direct ABO genotyping method that eliminates the need for DNA extraction from fresh blood, hair, and body fluid stains before PCR. Using a fast PCR instrument and an optimized polymerase, the genotyping method-which employs a multiplex allele-specific primer set for the simultaneous detection of three single-nucleotide polymorphism (SNP) sites (nucleotides 261, 526, and 803)-identifies A, B, O01/O02, O03, and cis-AB01 alleles in around 70 min from sample collection to electropherogram. Not only will this ABO genotyping method be efficiently used in forensic practice for rapid screening of samples before full-blown multilocus short tandem repeat profiling, but it will also demonstrate an example of rapid direct genotyping of SNPs that offers the advantages of time- and cost-efficiency, convenience, and reduced contamination during DNA analysis.  相似文献   
332.
Phentermine (PT) has been widely used as an anti-obesity drug. This drug has to be used with caution due to its close resemblance with amphetamines in its structure and toxicity profile. Recently, PT is in distribution by illegal modes and is found to be available through sources such as the internet, thus their misuse and/or abuse is threatening to be a serious social issue. In the present study, 32 cases of drug suspects were observed for PT abuse, detected using hair samples for drug analysis. PT and other amphetamines, such as methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxyamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA), were extracted using 1% HCl in methanol for 20 h at 38°C. The extracts were derivatized with trifluoroacetic anhydride (TFAA) and analyzed using gas chromatography/mass spectrometry (GC/MS). Among the 32 cases of PT abuse, MA and its main metabolite, AP were identified in seven cases and MDMA and its main metabolite, MDA were detected in two other cases.  相似文献   
333.
Numerous studies and interventions have been designed to either reduce the prevalence of risky behaviors (substance use, sexual activity, etc.) or increase the level of educational activity for adolescents. Research suggests that these two constructs may be related yet little is known about this relationship among African American youth. Archival data from the Risk Reduction Project was used to explore the connection between the protective factors of educational aspirations/expectations and recent participation in risky behavior. Results suggest that recent use of marijuana, alcohol to the point of intoxication, and sexual activity predicted lower aspirations and expectations among African American youth. From a positive youth development perspective, this study suggests the development of holistic interventions that build educational assets in youth, in addition to working to minimize risk behaviors. Limitations and suggestions for future research are also discussed.  相似文献   
334.
335.
中美关系将会全面寻求合作与竞争,但是基于中国的崛起和"美国霸权"的衰落,"合作中冲突"的局面可能会逐渐形成。通过加强联合与强调多边合作,中美两国在东北亚地区采取的下注战略都向着防止任何一方统治该区域的情况发生转型。除了中美关系的冲突或合作趋势之外,朝鲜半岛也存在卷入"他者化"或"国际化"的可能性。本文建议无论是韩美联盟还是中韩合作都应遵循独立适用原则,且我们应当探索战略性的普遍原则。  相似文献   
336.
Abstract Stella Miles Franklin (1879–1954) is best known for contributions to a uniquely Australian literary tradition. However, during her American years (1906–1915) when she worked in Chicago with the National Women's Trade Union League, Franklin wrote much unpublished fiction in the New Woman literary genre common to early-twentieth-century US women's traditions. This paper focuses on two such little-known unpublished stories: ‘Uncle Robert's Wedding Present’ (1908) and ‘Teaching Him’ (1909), discussing ways their entanglements with questions of marriage and economics are grounded in Franklin's work and personal life and in the intellectual influences that shaped her writing.  相似文献   
337.
The emergence of webOS on Palm devices has created new challenges and opportunities for digital investigators. With the purchase of Palm by Hewlett Packard, there are plans to use webOS on an increasing number and variety of computer systems. These devices can store substantial amounts of information relevant to an investigation, including digital photographs, videos, call logs, SMS/MMS messages, e-mail, remnants of Web browsing and much more. Although some files can be obtained from such devices with relative ease, the majority of information of forensic interest is stored in databases on a system partition that many mobile forensic tools do not acquire. This paper provides a methodology for acquiring and examining forensic duplicates of user and system partitions from a device running webOS. The primary sources of digital evidence on these devices are covered with illustrative examples. In addition, the recovery of deleted items from various areas on webOS devices is discussed.  相似文献   
338.
Surface coatings that can help deter and solve gun crime are described. These nanoengineered coatings have been applied and evaluated on brass cartridge cases, where they increase associative forensic evidence through nanotag donation to the handler and the retention of handler's DNA. In future we expect this approach to be used for other surfaces and conditions.  相似文献   
339.
This paper discusses the organization of the first international proficiency test (PT) programme on ketamine (K) and norketamine (NK) in hair samples. The primary objective of the programme was to evaluate the analytical capability of participating laboratories on hair analysis for K and NK via comparison of results. Authentic samples, instead of spiked samples were used in the programme to mimic the analysis of incorporated illicit drugs in real-life situations. Eight of the ten participating medical or forensic laboratories from Australia, France, Hong Kong, Italy, Singapore and the USA returned results to the organizer. Quantification methods from these laboratories were confined to GC-MS and LC-MS/MS. Performance assessment based on z-score indicated that only three laboratories achieved satisfactory results for both the analysis of K and NK. It was concluded that the overall performance of the participating laboratories was fair and there is still room for further improvement. Additional similarly designed PT programmes are recommended to be organized in order to encourage reliable measurements of illicit drugs in hair samples. Taking into account the substantial effect on the consensus values within limited number of data points, a recommendation on the provision of reference values assigned by accurate methods will be of benefit to small size PT programmes in the forensic field.  相似文献   
340.
The utilization of 3D computerized systems has allowed more effective procedures for forensic facial reconstruction. Three 3D computerized facial reconstructions were produced using skull models from live adult Korean subjects to assess facial morphology prediction accuracy. The 3D skeletal and facial data were recorded from the subjects in an upright position using a cone-beam CT scanner. Shell-to-shell deviation maps were created using 3D surface comparison software, and the deviation errors between the reconstructed and target faces were measured. Results showed that 54%, 65%, and 77% of the three facial reconstruction surfaces had <2.5 mm of error when compared to the relevant target face. The average error for each reconstruction was -0.46 mm (SD = 2.81) for A, -0.31 mm (SD = 2.40) for B, and -0.49 mm (SD = 2.16) for C. The facial features of the reconstructions demonstrated good levels of accuracy compared to the target faces.  相似文献   
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