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881.
882.
To answer the question whether a negative result of gas chromatographic blood analysis for components of chemical mace proves that no or at most only slight tear gas exposure can have occurred, animal experiments were carried out. In the blood of 10 guinea pigs, which were exposed to the contents of chemical mace for 1--6 h, the solvants 1,1,2-trichloro-1,2,2-trifluorethane (freon 113) and 1,1,1-trichloroethane could easily be detected--even 23 h after the end of exposure or after a storage of the blood samples for 18 weeks--whereas the lacrimator chloracetophenone (CN) could not be found at all. In vitro experiments showed that CN relatively quickly reacts with components of blood. Therefore, blood samples should be analyzed for CN after withdrawal as soon as possible. In case of inhalation of the contents of chemical mace, i.e., after the comparatively mildest form of CN application, most probably no traces of the lacrimator at all can pass into the blood due to the quick reaction of CN with proteins of the respiratory surface of the lung.  相似文献   
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886.
The complex nature of medieval Arabic compilations, with their evidence of manifold pieces and layers of diverse (older) text material, has been puzzling to many scholars of Islam. It has even caused some researchers to question the authenticity and credibility of information contained in these texts—and their value as historical sources—altogether.

An inquiry into the theoretical controversies at issue here constitutes the starting point of this article. Additionally, we will look at the categories and terms more frequently used in Western studies of the sources of Arabic compilations from about the eighth to the eleventh century Common Era (CE). The second part of the article offers an extensively annotated catalogue of categories and terms. This terminology, it is hoped, will help advance the assessment of classical Arabic compilations, for it takes the actual circumstances of the transmission of knowledge and the working techniques of compilers in medieval Islam into proper consideration. In conclusion, the paper illustrates how the proposed categories and terms are to be applied. It will become clear that the application of this kind of refined source-critical examination of individual classical Arabic texts is instrumental to a better understanding of medieval Muslim scholarship in general.  相似文献   

887.
Although many people displaced by Saddam's regime over the yearslooked forward to returning as soon as the 2003 war ended, anumber of problems emerged which continued to bedevil the returnprocess as late as one year after the war. These problems includedan unclear political future for the country, competing politicaland sectarian forces that often view IDPs and refugees as strategictools or weapons, a hesitant and initially undecided Coalitionpolicy on the return issue, unclear mandates for the variousactors that could assist with returns, lack of funding, andmost importantly of all, an extremely poor security situationwhich has impeded or even blocked all progress on the returnissue. Nonetheless, because Iraq's Ba'athist dictatorship wasthe overwhelming cause of displacement in the country to beginwith, the future does hold some hope for Iraqi displaced persons.This paper examines the causes of return problems in Iraq andhow various authorities in post-Ba'athist Iraq are addressingthe return issue. Particularly around the contested city ofKirkuk, problems relating to the return issue risk ignitingethnic conflict and possibly even civil war in Iraq as a whole.The article examines the return issue for the period from March2003 to June 2004, focusing especially on northern Iraq andKirkuk. The research presented here is based on fieldwork conductedin Iraq by the author between September 2003 and May 2004. Theauthor went to Iraq independently, with the assistance of aCanadian Department of National Defence post-doctoral researchgrant. Interviews were conducted with US and Coalition ProvisionalAuthority officials, Iraqi Interim Government officials, KurdistanRegional Government officials, NGO workers, and IDPs themselvesduring visits to camps around Kirkuk and Baghdad.  相似文献   
888.
A 1H nuclear magnetic resonance (1H NMR) method for the determination of gamma-hydroxybutyric acid (GHB) and gamma-hydroxybutyrolactone (GBL) in human serum and urine using spiked samples has been developed. The method gives linear responses (correlation coefficients of 0.99 or greater) over the concentration range 0.01 mg/mL to 4.0 mg/mL in urine and 0.3 mg/mL to 2.0 mg/mL in serum. No sample pretreatment is required. Studies of the chemical interconversion of GBL and GHB showed hydrolysis of GBL to be rapid at pH 11.54, slower and less complete (30% hydrolysis) at pH 2.54 and slowest at pH 7.0, reaching 30% hydrolysis in about 40 days. No esterification of GHB was observed at any pH.  相似文献   
889.
In a second test of an arthropod saturation hypothesis, we analyzed if the on-campus Anthropology Research Facility (ARF) at the University of Tennessee, Knoxville, with its 20+ yr history of carcass enrichment, is comparable to non-enriched sites in community structure of predatory and parasitic arthropods that prey upon the sarcosaprophagous fauna. Over a 12-day period in June 1998, using pitfall traps and sweep nets, 10,065 predaceous, parasitic, and hematophagous (blood-feeding) arthropods were collected from freshly euthanized pigs (Sus scrofa L.) placed at ARF and at three surrounding sites various distances away (S2-S4). The community structure of these organisms was comparable in most paired-site tests with respect to species composition, colonization rates, and evenness of pitfall-trap abundances on a per carcass basis. Site differences were found in rarefaction tests of both sweep-net and pitfall-trap taxa and in tests of taxonomic evenness and ranked abundances of sweep-net samples. Despite these differences, no evidence was found that the predatory/parasitic fauna at ARF was impoverished with fewer but larger populations as a result of carcass enrichment. Comparison of the sarcosaprophagous and predatory/parasitic faunas revealed a tighter (and more predictable) linkage between carrion feeders (sarcosaprovores) and their carrion than between carrion feeders and their natural enemies (predators and parasitoids), leading us to conclude that ARF is more representative of surrounding sites with respect to the sarcosaprovore component than to the predatory/parasitic component within the larger carrion-arthropod community.  相似文献   
890.
A clear positive case for anabolic steroids doping was confounded by alleged urine tampering during doping control procedures. Review of the chain of custody showed no flaws, but nevertheless the athlete was adamant that the urine sample should be analyzed for DNA in order to support her contention that she was not the donor of the sample. The results obtained showed that the urine sample that scored positive for steroids contained nuclear DNA that could not be matched to the DNA obtained from the athlete's blood. On the other hand, the same urine sample contained mitochondrial DNA whose nucleotide sequences spanning the hyper variable regions HV1 and HV2 proved to be identical to those determined in mitochondrial DNA amplified from the athlete's blood. The occurrence of an extraneous genotype is compatible with exogenous nuclear DNA admixture to the athlete's urine. Alternatively, taking in consideration the mitochondrial DNA, we could not exclude that a sibling or a maternal relative of the athlete could have acted as a donor of the urine utilized for doping control and DNA analysis. Both situations point to possible tampering of the urine by the athlete. Adjudication at CAS maintained previous national and international federation decision that there was no proof of a chain of custody flaw to justify the athlete's allegation of urine substitution after collection.  相似文献   
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