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91.
This paper describes a developmental validation study of three Miniplex sets covering 12 of the 13 CODIS loci. As these new sets will be used for the analysis of degraded and low level DNA, the validation studies were performed using 100-125 pg of DNA, the lowest input level at which peak balance, peak intensity, and allele consistency were stable. To demonstrate the applicability of the Miniplex sets to forensic casework, these validation studies were completed in accordance with the Scientific Working Group on DNA Analysis Methods (SWGDAM). A range of tests were performed including studies of concordance with standard multiplex kits, sensitivity and reproducibility, and PCR amplification conditions. Additionally, studies of mixtures, nonhuman and environmentally degraded DNA, and simulated forensic samples were performed. Our results demonstrate that Miniplex STR amplification procedures are a robust and sensitive tool for the analysis of degraded DNA.  相似文献   
92.
Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.  相似文献   
93.
94.
A new set of multiplexed PCR primers has been applied to the analysis of human skeletal remains to determine their efficacy in analyzing degraded DNA. These primer sets, known as Miniplexes, produce shorter amplicons (50-280 base pairs (bp)) than standard short tandem repeat (STR) kits, but still utilize the 13 CODIS STR loci, providing results that are searchable on national DNA databases. In this study, a set of 31 different human remains were exposed to a variety of environmental conditions, extracted, and amplified with commercial and Miniplex DNA typing kits. The amplification efficiency of the Miniplex sets was then compared with the Promega PowerPlex 16 system. Sixty-four percent of the samples generated full profiles when amplified with the Miniplexes, while only 16% of the samples generated full profiles with the Powerplex 16 kit. Complete profiles were obtained for 11 of the 12 Miniplex loci with amplicon sizes less than 200 bp. These data suggest smaller PCR amplicons may provide a useful alternative to mitochondrial DNA for anthropological and forensic analysis of degraded DNA from human skeletal remains.  相似文献   
95.
The intra- and inter-examiner reliability was evaluated for hand-held 3D laser scanning technology when it was combined with localization of landmarks for craniometry. The data from the laser surface scanning were compared with those of conventional direct measuring. Using thirty unidentified skulls requested for individual identification, measurements were taken of the line distances from lambda to 26 landmarks, and also for seven breadth parameters. For the laser surface scanning, two examiners performed replicate measurements with an interval of 1 week. In the conventional direct measuring, the first examiner took replicate measurements with a 1-week interval. To assess intra- and inter-examiner reliabilities, the intraclass correlation coefficient was used. Analysis of variance with repeated measures for each parameter was performed to compare the conventional method with the 3D scanning method. Both the 3D scanning and conventional methods showed excellent intra-examiner reliabilities, and the 3D laser scanning method also showed excellent inter-examiner reliability. A statistical difference between the two examiners was found only in nasal breadth in the 3D laser scanning method. There was no significant difference between the two measuring methods, though the 3D laser scanning method tended to give a slightly lower reading. Collectively, the 3D laser scanning method with point localization is a useful method with excellent reliability, and it can replace the conventional direct measuring method in craniometry.  相似文献   
96.
Dextromethorphan (DMP), an antitussive, is one of the most popular drugs among the younger generation in Korea. It usually is taken for its hallucinogenic properties and overdoses have been responsible for the fatalities that have been reported frequently. To control the abuse of DMP, the authorities restricted its use through classifying it as a controlled drug on October 2003. The purpose of this study is to provide a standard method for the analysis of DMP and its main metabolite, dextrorphan (DTP) in biological specimens. At first we established a standard operating procedure (SOP) for DMP/DTP in urine, and a method validation was performed. We also quantified DMP from 16 drug abuser's urine samples all of which were positive in the screening test for DMP. For the detection of DMP/DTP, urine samples were adjusted with 6N NaOH (pH 11) and extracted with ethylacetate. Thin layer chromatography was used as the screening test, and the final identification for DMP/DTP was used by GC/MS. The ions (m/z 271 for DMP, m/z 257 for DTP and m/z 86 for lidocaine as internal standard) were extracted from the full scan mass spectrum and were used for quantification. The selectivity, linearity of calibration, accuracy, within- and between day precision, limit of detection and quantification, recovery and stability were examined as parts of the method validation. Extracted calibration curves were linear from 100 to 2000 ng/mL for DMP and DTP with correlation coefficients better than 0.999. Limit detection was 50 ng/mL for DMP and DTP. Within-run precision (%CV) for DMP and DTP at three different concentrations (100, 500 and 1000 ng/mL) was 6.10-18.85%, and between-run precision was 1.70-7.86% for DMP and DTP. Absolute recovery for DMP and DTP was 57-74%, and relative recovery (extraction efficiency) was 80-89%. For 16 drug abuser's urine samples, the concentrations of DMP and DTP were 0.16-52.63 and 0.41-23.75 microg/mL, respectively. Method validation is an important requirement in the practice of chemical analysis, and it will be particularly useful in verifying the reliability of analytical results in the field of forensic science.  相似文献   
97.
This article investigates the current state and future prospects of trade between South Korea and China, with a focus on China's Bohai region. First, it compares basic economic profiles, including trade patterns of China, Bohai, and Korea. Then, it explores trade prospects between these economies using the aid of the indices, such as export similarity and trade complementarity. The article also examines the trade creation and diversion effects of trade between Korea, China, and Bohai during the last decade, and, finally, presents alternative future trade projections. Editor's Note: The three articles in this section were originally prepared for and presented at an international conference on Regional Development in the Yellow Sea Rim, in February 1991, in Seoul, Korea. The conference was part of a two-year collaborative study on regional development in the Yellow Sea Rim, involving researchers from China, South Korea, the United States, and Japan. The study was organized by the East-West Population Institute of Hawaii and supported by many research institutions and government agencies in China and the Republic of Korea. In particular, the State Science and Technology Commission of China and the Korea Research Institute for Human Settlements are acknowledged for their generous support.  相似文献   
98.
As the figures for wife abuse cases in Hong Kong continue to rise, the author questions the effectiveness of current law in controlling domestic violence. It is argued that the present law, which punishes abusers by putting them into jail, can neither change their violent behavior nor repair the personal/familial relationships of the parties involved. It is within this context that the author proposes the adoption in Hong Kong of ``court-mandated counseling', a scheme that has been practiced not only in the United States, but also in Mainland China, and Taiwan. It is, however, noted that such a counseling programme must be sensitive to the gendered legal politics and the local cultural discourse, as, otherwise, the scheme will operate to (re-)strengthen both the male dominating structure and the postcolonial hegemony.  相似文献   
99.
Ketamine (KT) is widely abused for hallucination and also misused as a "date-rape" drug in recent years. An analytical method using positive ion chemical ionization-gas chromatography-mass spectrometry (PCI-GC-MS) with an automatic solid-phase extraction (SPE) apparatus was studied for the determination of KT and its major metabolite, norketamine (NK), in urine. Six ketamine suspected urine samples were provided by the police. For the research of KT metabolism, KT was administered to SD rats by i.p. at a single dose of 5, 10 and 20mg/kg, respectively, and urine samples were collected 24, 48 and 72 h after administration. For the detection of KT and NK, urine samples were extracted on an automatic SPE apparatus (RapidTrace, Zymark) with mixed mode type cartridge, Drug-Clean (200 mg, Alltech). The identification of KT and NK was by PCI-GC-MS. m/z238 (M+1), 220 for KT, m/z 224 (M+1), 207 for NK and m/z307 (M+1) for Cocaine-D(3) as internal standard were extracted from the full-scan mass spectrum and the underlined ions were used for quantitation. Extracted calibration curves were linear from 50 to 1000 ng/mL for KT and NK with correlation coefficients exceeding 0.99. The limit of detection (LOD) was 25 ng/mL for KT and NK. The limit of quantitation (LOQ) was 50 ng/mL for KT and NK. The recoveries of KT and NK at three different concentrations (86, 430 and 860 ng/mL) were 53.1 to 79.7% and 45.7 to 83.0%, respectively. The intra- and inter-day run precisions (CV) for KT and NK were less than 15.0%, and the accuracies (bias) for KT and NK were also less than 15% at the three different concentration levels (86, 430 and 860 ng/mL). The analytical method was also applied to real six KT suspected urine specimens and KT administered rat urines, and the concentrations of KT and NK were determined. Dehydronorketamine (DHNK) was also confirmed in these urine samples, however the concentration of DHNK was not calculated. SPE is simple, and needs less organic solvent than liquid-liquid extraction (LLE), and PCI-GC-MS can offer both qualitative and quantitative information for urinalysis of KT in forensic analysis.  相似文献   
100.
This article focuses on South Asia's role in China's Maritime Silk Road (MSR) initiative. Given the saliency of this MSR enterprise as part of ChinesePresident Xi Jinping’s “One-Belt-One-Road” strategy, how this ambitious scheme impacts China’s relations with South Asian states along the MSR’s route, i.e. India, Pakistan, Sri Lanka, Maldives and Bangladesh, merits investigation. The fate of the MSR will be determined by China’s relations with these states, since South Asia is in the middle of major sea-lanes between East/Southeast Asia and Middle East/Europe. The study examines the intentions and executions of China’s MSR projects in South Asia, evaluates the political and economic calculations of participating in the MSR for regional states, and identifies actions taken by them that can decide the initiative’s success. Politically, reactions of South Asian states to the MSR are explained as: fear of expanding Chinese influence in the Indian Ocean for India; and attempts by which Pakistan, Sri Lanka, Maldives and Bangladesh use China to counteract possible domination by India. Economically, two MSR pathways for South Asian states are analyzed: increases in Chinese infrastructure investments; and expansion in South Asia-China trade; both of which are reducible by loans owed to China, or “strings”/conditions attached.  相似文献   
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