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311.
As is commonly the case in new areas of research, workplace bullying researchers and practitioners have struggled to establish a single agreed-upon definition of this phenomenon. As a consequence, there are numerous definitions of workplace bullying currently in use around the world to investigate this serious workplace issue, to educate the workforce about this form of harassment and to assess claims involving allegations of workplace bullying. Additionally, little is known about how employees and people in general define workplace bullying behaviour, and whether current researcher, practitioner and legal definitions coincide with lay definitions of bullying. To compare researcher, practitioner and legal definitions of workplace bullying with lay definitions, the content of definitions composed by adults from diverse personal and professional backgrounds (N=1095) was analysed. Results confirmed that components commonly used by researchers and practitioners, including the occurrence of harmful and negative workplace behaviours, were frequently cited by participants as central defining components of bullying behaviour. In addition, lay definitions often included themes of fairness and respect. The emergence of these themes has important consequences for organisations responding to, and attempting to prevent the occurrence of workplace bullying behaviour in that organisations in which bullying is tolerated may violate both local laws as well as their ethical responsibility to provide employees with a safe, professional and respectful workplace.  相似文献   
312.
Amphetamine samples were analysed by gas chromatography-mass spectrometry (GC-MS), and the peak areas of 33 target compounds were transformed by applying various pretreatment techniques. The objective was to optimise the ability of a number of distance metrics to establish links between samples of amphetamine originating from the same batch (henceforth referred to as linked distances). Furthermore, partial least squares discriminant analysis (PLS-DA) was used to evaluate the effects of various pretreatment methods on separation of amphetamine batches synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The most efficient way to pretreat GC-MS data varied for the different distance metrics, although best results were obtained when data were normalised to the sum of peak areas, and either the fourth root or a logarithm was applied to the normalised data. When pretreating normalised data by fourth root transformation, Pearson correlation was the distance metric that was most successful at finding linked samples. Normalisation and the use of fourth root also represented the best method of pretreating data when employing PLS-DA to separate samples synthesised by different routes. To achieve a faster and more user-friendly procedure for evaluating chromatograms, experiments were performed in which the number of target compounds used to compare samples was reduced. The effect of each compound that was removed was studied by applying PLS-DA and by using Pearson correlation to calculate linked distances as well as unlinked distances (between samples from different batches of amphetamine). Considering both links between samples from the same batch and separation of samples synthesised by different routes, the best results were obtained with the data set comprising 26 compounds. Finally, it was found that the profiling method developed in this work was superior to an existing technique with respect to separating linked and unlinked distances.  相似文献   
313.
The entrepreneurial puzzle: explaining the gender gap   总被引:1,自引:0,他引:1  
We document the substantial gender gap that exists among university scientists with regard to entrepreneurial activity using a variety of measures and explore factors leading to the disparity. We focus particularly on the biomedical sciences. The contextual explanation that women are under-represented in the types of positions from which faculty typically launch entrepreneurial activity is the most obvious. But the data suggest that for the biomedical sciences context is not sufficient in explaining the entrepreneurial gap. We look elsewhere to factors affecting supply and factors affecting demand. The former include gender differences in attitudes towards risk, competition, “selling” of “science,” type of research and geographic location. The latter include the role of networks, preferences of venture capitalists and “gender discounting.” We explore the associated hypotheses. We provide few tests and conclude that the research agenda is wide open and interesting.
Paula E. StephanEmail:
  相似文献   
314.
Tianeptine (Stablon), although structurally similar to tricyclic antidepressants, acts by enhancing the reuptake of serotonin. A fatal case is presented involving a 26-year-old man, found lying in bed with a "mushroom of foam" around his mouth. Empty blister packs of Stablon and a suicide note were found next to the body. A liquid-liquid extraction procedure with n-hexane: ethyl acetate and n-hexane: 2-propanol, followed by LC-DAD-MS analysis, using positive mode electrospray ionization was performed. The detection limit was 0.001 microg/mL. The toxicological results revealed the following tianeptine concentrations in the post-mortem samples: blood 5.1 microg/mL; urine 2.0 microg/mL; liver 23 microg/g; stomach contents 22 mg. Femoral blood analyses also revealed an ethanol concentration of 0.53 g/L. The present method was also developed and validated for the other post-mortem specimens, since no previous published data had confirmed the post-mortem distribution of tianeptine. The absence of other suitable direct causes of death (macroscopic or histological) and the positive results achieved with the toxicological analysis led the pathologist to rule that death was due to an intoxication caused by the suicidal ingestion of tianeptine in combination with alcohol.  相似文献   
315.
Since the beginning of the twenty-first century, expansion of the formal credit supply in Brazil has promoted the ‘financial inclusion’ of the low-income population, especially through instalment plans offered by large retail chains. This article aims to analyse the impacts of formal credit availability on the consumption of electrical and electronic goods by residents of Jardim Helena, a neighbourhood in São Paulo's periphery. Through the collection and analysis of qualitative and quantitative data, this study reveals how the instalment plan can stimulate consumption among the low-income population, with a significant impact on household budgets, raising the risk of indebtedness.  相似文献   
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