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71.
A rapid and sensitive method using LC-MS/MS triple stage quadrupole for the determination of traces of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, “ecstasy”), 3,4-methylenedioxyethamphetamine (MDEA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair, blood and urine has been developed and validated. Chromatography was carried out on an Uptisphere ODB C18 5 μm, 2.1 mm × 150 mm column (Interchim, France) with a gradient of acetonitrile and formate 2 mM pH 3.0 buffer. Urine and blood were extracted with Toxitube A® (Varian, France). Segmented scalp hair was treated by incubation 15 min at 80 °C in NaOH 1 M before liquid–liquid extraction with hexane/ethyl acetate (2/1, v/v). The limits of quantification (LOQ) in blood and urine were at 0.1 ng/mL for all analytes. In hair, LOQ was <5 pg/mg for MA, MDMA, MDEA and MBDB, at 14.7 pg/mg for AP and 15.7 pg/mg for MDA. Calibration curves were linear in the range 0.1–50 ng/mL in blood and urine; in the range 5–500 pg/mg for MA, MDMA, MDEA and MBDB, and 20–500 pg/mg for AP and MDA. Inter-day precisions were <13% for all analytes in all matrices. Accuracy was <20% in blood and urine at 1 and 50 ng/mL and <10% in hair at 20 and 250 pg/mg. This method was applied to the determination of MDMA in a forensic case of single administration of ecstasy to a 16-year-old female without her knowledge during a party. She suffered from hyperactivity, sweating and agitation. A first sample of urine was collected a few hours after (T + 12 h) and tested positive to amphetamines by immunoassay by a clinical laboratory. Blood and urine were sampled for forensic purposes at day 8 (D + 8) and scalp hair at day 60 (D + 60). No MDMA was detected in blood, but urine and hair were tested positive, respectively at 0.42 ng/mL and at 22 pg/mg in hair only in the segment corresponding to the period of the offence, while no MDA was detectable. This method allows the detection of MDMA up to 8 days in urine after single intake.  相似文献   
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After decades of refinement, DNA testing methods have become essential tools in forensic sciences. They are essentially based on likelihood ratio test principle, which is utilized specifically, by using as prior knowledge the allele frequencies in the population, to confirm or refute a given kinship hypothesis made on two genotypes. This makes these methods ill suited when allele frequencies or kinship hypotheses are unavailable. In this paper, we introduce DNAc, a new clustering methodology for DNA testing based on a new similarity measure that allows an accurate retrieval of the degree of relatedness among two or more genotypes, without relying on kinship hypotheses or allele frequencies in the population. We used DNAc in analyzing microsatellite DNA sequences distributed among 12 genotypes from normal individuals from two distinct families. The results show that DNAc accurately determines kinship among genotypes and further gathers them in the appropriate kinship groups.  相似文献   
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Forensic pathologists often refer to the cardioinhibitory reflex cardiac arrest (CiRCA) following short neck trauma as a mechanism of death. We sought via a systematic review of the literature to identify circumstances under which carotid bifurcation stimulation could lead to death. Two independent reviewers selected case studies or reports from Medline, ISI Web of Knowledge, and Embase. Circumstances and contributory factors were extracted for each case. From the available data, authors independently assessed whether CiRCA was highly probable (no alternative explanation possible), probable (alternative explanation possible), or unlikely (alternative explanation highly probable). A narrative approach was used to define circumstances in which CiRCA remained possible. From the 48 published cases evoking CiRCA as a possible cause of death between 1881 and 2009, 28 were most likely to result of other mechanism of death (i.e., cerebral hypoxia due to carotid compression, mechanical asphyxia, myocardial infarction). CiRCA remained possible for 20 cases (including five based on anecdotal evidence only) with only one case with no alternative explanation other than CiRCA. Our findings support the presumption that reflex cardiac arrhythmia due to carotid bifurcation stimulation cannot provoke death alone. Actual state of knowledge suggests CiRCA might be contributory to death in the presence of drug abuse and/or cardiac pathology, often associated with physical and/or mental excitation.  相似文献   
76.
Purpose. Previous experiments have demonstrated asymmetrical scepticism in investigators' judgments of criminal evidence – evidence inconsistent (vs. consistent) with the dominant hypothesis about a case is judged as less reliable. In addition, some types of evidence (e.g., witness testimony) are more susceptible to asymmetrical scepticism than others (e.g., DNA evidence), indicating varying degrees of elasticity. This article proposes that inconsistent evidence arouses cognitive dissonance, and that the dissonance can be reduced through either asymmetrical scepticism (for high‐elasticity evidence) or belief change (for low‐elasticity evidence). The hypotheses are tested in two experiments. Methods. In both experiments, law students made a preliminary judgment about the guilt of a suspect in a homicide case, and subsequently received a piece of DNA or witness evidence which was either consistent or inconsistent with the preliminary judgment. The extent to which participants changed their guilt judgments, judged the additional evidence as reliable, and felt dissonance served as the main dependent variables. Results. Inconsistent (vs. consistent) evidence did arouse stronger dissonance, but only for witness (and not DNA) evidence. Experienced dissonance (Experiment 1) and dissonance reduction (Experiment 2) accounted for the effect of the evidence on changes in guilt judgments, but not for the effect on reliability judgments. The greatest dissonance reduction was observed among participants who received inconsistent witness evidence but did not change their guilt judgments accordingly. Conclusions. It appears that dissonance plays a significant, although complex, role in investigative judgments of guilt and reliability. Alternative dissonance‐reducing mechanisms that can account for the findings and practical implications are discussed.  相似文献   
77.
The authors report on a macroscopic and microscopic study of human mandible bone lesions achieved by a single-blade knife and a hatchet. The aim of this work was to complete the previous data (scanning electron microscopy analysis of bone lesions made by a single-blade knife and a hatchet, on human femurs) and to compare the lesions of the femur with those of the mandible. The results indicate that the mandible is a more fragile bone, but the features observed on the mandible are quite similar to those previously observed on the femur. This work spells out the main scanning electron microscopy characteristics of sharp (bone cutting) and blunt (exerting a pressure on the bone) mechanisms on human bone. Weapon characteristics serve to explain all of these features.  相似文献   
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Abstract

Since China agreed to join the international counter-piracy coalition in late 2008, a watershed development in Chinese strategic policy, Beijing's engagement in Somalia is now following two separate streams. First, China is seeking to engage Somalia as part of its expanding number of African diplomatic partners via its participation in the coalition. Second, China is attempting to demonstrate, on the international level, its growing commitment to developing its naval capabilities, and protecting its maritime trade interests, by engaging in multilateral and coalition-based operations, namely to combat piracy off the Somali coast, in order to deflect criticism from the United States and its allies of China's overall military expansion and modernization.  相似文献   
80.
ABSTRACT

A recent trend in public administration studies has been to assess how public management is performed by politicians and top civil servants. Surprisingly, little is known about how these different posts develop their management roles. Following seminal management studies, we focus on core management roles to compare the ways in which politicians and top civil servants develop their management responsibilities within public organizations. Empirical evidence is provided by triangulating three separate studies developed in Spain. Results from the triangulation show that there is unmistakable evidence of differentiations between politicians and top civil servants when performing their managerial roles.  相似文献   
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