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751.
《国际相互影响》2012,38(4):353-380

We conducted an experimental test of spiraling behavior, sex differences, and uncertainty in a simulated crisis situation. We investigated the relationship between weapons acquisition and the likelihood of engaging in aggressive behavior, such as going to war. The sample included 100 male and female subjects who participated in a crisis simulation in same‐sex dyads; each student was instructed to role play the leader of a country in conflict with another leader over a nearby island replete with newly discovered oil resources. Participants were randomly assigned to stimulus materials that manipulated the certainty of the information they received about their partner's force structure. In four cycles of decision‐making, each participant made procurement decisions, took an action related to the conflict, including decisions about going to war, completed questionnaires on characteristics such as the hostility and trustworthiness of themselves and their opponents, and wrote messages to the other member of the pair. The results of the study demonstrate a strong relationship between weapons acquisition and hostility. In addition, we found large and robust sex differences, showing that men are much more likely than women to acquire weapons and engage in aggressive behavior at every stage. There was no effect of uncertainty on either arms procurement or aggression.  相似文献   
752.
In MWB Business Exchange Centres Ltd v Rock Advertising Ltd the Court of Appeal held that when an ongoing contract is varied so that one party's obligation to pay money is reduced, the variation is binding as long as the other party receives a practical benefit. In doing so, the Court of Appeal effectively confined the rule in Foakes v Beer to one‐off payments. This raises serious questions about the continued survival of Foakes v Beer. On the other hand, the Court of Appeal ensured that Foakes v Beer would not be killed off via equity by moving away from the suggestion in Collier v P & M J Wright (Holdings) Ltd that an agreed part‐payment of a debt by a debtor will always raise an estoppel preventing the creditor from demanding the remainder of the debt.  相似文献   
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The detection of DNA is inhibited in cases of sexual assault involving condom use. Trace evidence, including condom lubricant residues, provides crucial associative evidence in such cases. The existing Fourier transform infrared spectroscopy (FTIR) methods for lubricant analysis and detection are limited with regard to sensitivity and discrimination. The aim of this research was to establish a new method as an alternative to FTIR for the analysis of condom lubricant residues. Pyrolysis gas chromatography-mass spectrometry (PyGC-MS) and GC-MS are highly sensitive methods of analysis for a wide range of chemical substances. PyGC-MS and GC-MS were used to analyze condom lubricants in standard solution, from clean swabs and from postcoital swabs. Pyrolysis of polydimethylsiloxane (PDMS) lubricant forms cyclic products known as cyclic dimethyl siloxanes (DMS), which are separated and detected by the GC-MS. The polyethylene glycol (PEG) lubricant can be analyzed by GC-MS directly from solution. The methods of extraction and analysis presented in this paper were shown to be significantly more sensitive than FTIR for the analysis of PDMS and PEG condom lubricants. PDMS was detected as low as 1 mug in standard solution and from clean swabs using the PyGC-MS method. PEG was detected as low as 0.5 microg from standard solution and 50 mug from clean swabs using the GC-MS method. Unfortunately, we were unable to provide further discrimination between condom brands and subbrands. The methods established throughout the research were used successfully to detect condom lubricants from donated postcoital swabs. Lubricants were detected in abundance on swabs 12 h postcoitus. Recommendations are made regarding implementation of new methods for routine analysis of casework samples along with strict pyrolysis interpretation criteria to minimize the possibility of misinterpretation of false positives.  相似文献   
757.
Although the need for early intervention for mental health difficulties is widely acknowledged, few studies have attempted to explicitly increase actual help seeking behavior for mental health difficulties. Students in intervention classrooms received two one-hour, in-class workshops on distress and help seeking and were compared to students in non-intervention classrooms in a 2-level hierarchical model. More frequent help seeking behavior and more mental health referrals were observed among students in the intervention group than among students in the comparison group. Effects were moderated by the level of distress experienced by students, but not by help seeking attitudes, and could not be accounted for by school staff referrals or website utilization. Results showed that help seeking behavior for mental health difficulties and mental health referrals can be increased with only a moderate investment in time, but that benefits of school-based intervention may be greatest among students with specific needs, such as high levels of distress.
Darcy A. SantorEmail:
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Detection of trace quantities of explosive residues plays a key role in military, civilian, and counter-terrorism applications. To advance explosives sensor technology, current methods will need to become cheaper and portable while maintaining sensitivity and selectivity. The detection of common explosives including trinitrotoluene (TNT), cyclotrimethylenetrinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, 2,4,6-trinitrophenyl-N-methylnitramine, and trinitroglycerin may be carried out using a three-step process combining "turn-off" and "turn-on" fluorimetric sensing. This process first detects nitroaromatic explosives by their quenching of green luminescence of polymetalloles (lambda em approximately 400-510 nm). The second step places down a thin film of 2,3-diaminonaphthalene (DAN) while "erasing" the polymetallole luminescence. The final step completes the reaction of the nitramines and/or nitrate esters with DAN resulting in the formation of a blue luminescent traizole complex (lambda(em) = 450 nm) providing a "turn-on" response for nitramine and nitrate ester-based explosives. Detection limits as low as 2 ng are observed. Solid-state detection of production line explosives demonstrates the applicability of this method to real world situations. This method offers a sensitive and selective detection process for a diverse group of the most common high explosives used in military and terrorist applications today.  相似文献   
759.
The study aim was to evaluate the feasibility of a Fourier-transformed infrared (FT-IR) analyzer for out-of-laboratory use by screening the exhalations of inebriated individuals, and to determine analysis quality using common breath components and solvents. Each of the 35 inebriated participants gave an acceptable sample. Because of the metabolism of 2-propanol, the subjects exhaled high concentrations of acetone in addition to ethanol. Other volatile ingredients of technical ethanol products (methyl ethyl ketone, methyl isobutyl ketone, and 2-propanol) were also detected. The lower limits of quantification for the analyzed components ranged from 1.7 to 12 microg/L in simulated breath samples. The bias was +/-2% for ethanol and -11% for methanol. Within-day and between-day coefficients of variation were <1% for ethanol and <4% for methanol. The bias of ethanol and methanol analyses due to coexisting solvents ranged from -0.8 to +2.2% and from -5.6 to +2.9%, respectively. The FT-IR method proved suitable for use outside the laboratory and fulfilled the quality criteria for analysis of solvents in breath.  相似文献   
760.
Abstract: Accurate age‐at‐death estimates are crucial to forensic anthropologists when onstructing biological profiles aimed at narrowing a missing‐persons list and to allow for timely and efficient identification of an unknown victim. The present contribution evaluates the utility of three new age‐at‐death estimation techniques recently proposed by Samworth and Gowland (2007). Results indicate that, in the samples under study, the Samworth and Gowland estimates from the pubic symphysis and auricular surface perform similar to alternate phase methods. The combined method does not appear to further enhance either the precision or the accuracy of the single pubic symphysis age‐at‐death estimate. In conclusion, these new methods seem to be more robust to distribution deviations than originally proposed by Samworth and Gowland (2007). They are therefore suitable for immediate and reliable forensic usage in the United States and worthy of further research for their use in North American forensic contexts.  相似文献   
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