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621.
Gamma hydroxybutyric acid (GHB) concentrations in humans and factors affecting endogenous production
Elliott SP 《Forensic science international》2003,133(1-2):9-16
The endogenous nature of the drug of abuse gamma hydroxybutyric acid (GHB) has caused various interpretative problems for toxicologists. In order to obtain data for the presence of endogenous GHB in humans and to investigate any factors that may affect this, a volunteer study was undertaken. The GHB concentrations in 119 urine specimens from GHB-free subjects and 25 urine specimens submitted for toxicological analysis showed maximal urinary GHB concentrations of 3mg/l. Analysis of 15 plasma specimens submitted for toxicological analysis detected no measurable GHB (less than 2.5mg/l). Studies in a male and female volunteer in which different dietary food groups were ingested at weekly intervals, showed significant creatinine-independent intra-individual fluctuation with overall urine GHB concentrations between 0 and 2.55, and 0 and 2.74mg/l, respectively. Urinary concentrations did not appear to be affected by the particular dietary groups studied.The concentrations measured by gas chromatography with flame ionisation detection (GC-FID) and gas chromatography with mass spectrometry (GC-MS) lend further support to the proposed urinary and plasma interpretative cut-offs of 10 and 4mg/l, respectively, where below this it is not possible to determine whether any GHB detected is endogenous or exogenous in nature. 相似文献
622.
In December 2002, in its ongoing efforts to secure access to affordable HIV/AIDS treatment for all South Africans, the grassroots organization Treatment Action Campaign (TAC) initiated two new proceedings over governmental failure to act to prevent mother-to-child transmission of HIV. In March 2003, it launched a national civil disobedience campaign to pressure government into implementing a national treatment and prevention plan, including taking measures to ensure access to affordable medicines. 相似文献
623.
Those interested in political phenomena such as voting havefound random utility models, originally developed for decisionssuch as transportation choice, especially attractive, as theunderlying model can yield a statistical model with a few simple,realistic assumptions. Unfortunately, such models have provendifficult to apply to situations with more than two votes andthree alternatives or an unknown cutpoint. Additionally, aswe show, standard applications of such models to voting, whileproducing consistent parameter estimates, yield standard errorsthat are too small and, due to a failure to employ all relevanttheoretical information, biased ideal point estimates. We specifya general model applicable to any number of votes and alternatives,with correct standard errors and unbiased ideal point estimates.We apply this model to a number of cases studied by previousscholars involving legislative voting over the minimum wage:(1) when there are two votes and two known cutpoints (K. Krehbieland D. Rivers, American Journal of Political Science, 1988,32, 11511174); (2) when there are three votes and threeknown cutpoints (J. Wilkerson, American Journal of PoliticalScience, 1991, 35, 613623); and (3) when there are threevotes but where one cutpoint is unknown given a lack of knowledgeabout the impact of a policy (J. Wilkerson, American Journalof Political Science, 1991, 35, 613623) or the possibilityof sophisticated voting (C. Volden, Journal of Politics, 1998,60, 149173). We show that in various contexts our analysisimproves on existing methods, yielding consistent and efficientideal point estimates and a better-fitting model with improvedpredictive accuracy. 相似文献
624.
The increasing suicide rate in South Korea in recent decades was found to be associated with measures of social integration/regulation (birth and divorce rates). 相似文献
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627.
Lee JS Han EY Lee SY Kim EM Park YH Lim MA Chung HS Park JH 《Forensic science international》2006,161(2-3):209-215
Organic impurities of methamphetamine may show different patterns by synthesis. In the present study, we tried to find the impurities reflecting the conditions of synthesis by comparing impurity patterns of the methamphetamine samples synthesized by different methods. Sixteen methamphetamine samples were synthesized from ephedrine and pseudoephedrine by the three different manufacturing methods of Emde, Nagai and Moscow. The synthesized samples were extracted with ethyl acetate containing four internal standards, and the patterns of the organic impurities were investigated by GC-MS and GC-FID . Through the investigation, we found 10 peaks appearing in the latter part of GC chromatograms are characteristic to synthesis. The areas of the selected peaks were converted to the variables suitable for the statistical calculation, and the synthesized samples could be classified into four groups through the resultant cluster analysis. 相似文献
628.
Many suspected victims of surreptitious drug and/or alcohol administration may present to hospitals or healthcare centres and never come to the attention of forensic or law enforcement professionals. Therefore, it is necessary to include clinical toxicological findings in order to assess the growing perception that instances have become more widespread within society. Between July 2002 and June 2004, 180 requests were received for toxicological analysis of individuals presenting to their GP or hospital following self-reported or suspected surreptitious drug administration (e.g. "spiked drink"). There was a rise of 77% in the number of requests from 2002-2003 to 2003-2004 which peaked in December of each year (most likely due to the increased socialization of people during the festive season). Between 2002 and 2004, 34% of patients were male and 66% were female with an overall average age of 25 (range 11-73). Following urinary analysis using immunoassay and gas chromatography (mass spectrometry, flame-ionisation detection and nitrogen-phosphorus detection), 59% of cases were negative for drugs and alcohol in 2002-2003 and 51% in 2003-2004. Drugs or alcohol were detected in 32% of cases in 2002-2003 and in 45% in 2003-2004. Out of the 169 cases analysed, ethanol (alcohol) was the most commonly detected compound (24% of cases), followed by amphetamines (amphetamine, MDMA, MDA, MDEA--11% of cases), cannabinoids (9% of cases), benzodiazepines (temazepam, nordiazepam, oxazepam--9% of cases), cocaine (4% of cases), opiates (dihydrocodeine, codeine--2% of cases), chlorpheniramine (0.6% of cases), ephedrine 0.6% of cases), fluoxetine (0.6% of cases), tramadol (0.6% of cases) and zopiclone (0.6% of cases). No gamma-hydroxybutyrate (GHB), gamma-butyrolactone (GBL) or flunitrazepam was detected in the cases analysed. 相似文献
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630.