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21.
A new migration pessimism argues that the economic benefits of international labour migration for migrant households may not justify the social costs. This article provides a test of this argument based on the author's survey of 304 households in Jerez municipio (municipality), Zacatecas, Mexico, in 2009. The results indicate that active households (those with at least one migrant abroad) perceived their economic situation to have improved more, but both their social cohesion and their happiness to be less than those of non‐active households. Social cohesion (family unity and maintenance of values) is shown to be pivotal in the happiness differential enjoyed by the non‐active households.  相似文献   
22.
目的 探究无机元素在金寨地区仿野生茯苓不同用药部位中的分布及在土壤中的富集特点。方法 采用微波消解法处理茯苓皮、白茯苓、赤茯苓及其菌核生长附近土壤,应用电感耦合等离子体质谱法测定茯苓不同部位及其土壤中K、Na、Mg、Fe、Mn、Zn、Cu、Se等11种无机元素含量。结果 金寨地区仿野生茯苓各部位元素分布有一定差异,大多数元素在茯苓皮中含量较高,茯苓不同部位总的无机元素含量从高至低顺序为茯苓皮、赤茯苓、白茯苓;茯苓不同部位对无机元素的吸收有选择性,但均以K、Fe、Mg、Na含量较高;茯苓不同部位对11种元素的富集系数存在差异,变化范围为0.005 2~0.782 3。结论 所建立的电感耦合等离子体质谱法简便、准确,适用于金寨地区仿野生茯苓不同部位及土壤中11种无机元素的含量测定。  相似文献   
23.
This paper addresses B. F. Skinner's utopian vision for enhancing social justice and human well‐being as it was introduced in his 1948 novel, Walden Two. In the first part, we address the historical, intellectual, and social context that situates the book in the utopian genre, the critiques of its premises and practices, and the fate of intentional communities patterned on the book. In the second part, we review practices in Skinner's book that advance social justice and human well‐being under the themes of health, wealth, and wisdom, and then focus on contemporary practices that are the legacy of his vision. His vision was neither the a priori truth of a particular premise about human behavior or a necessary practice (blueprint) for an intentional community but rather the use of empirical methods to discover premises and practices that work to advance the health, wealth, and wisdom of individuals and survival of the culture.  相似文献   
24.
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures.  相似文献   
25.
In the last decades, municipal mergers have been one major element of local government reforms in Switzerland and beyond. In this article, we describe and analyze the political effects of this development. We use a quasi‐experimental setting to test the impact of municipal mergers on electoral participation. We find that in merged municipalities, the decrease in turnout is significantly stronger than in non‐merged municipalities. Further, the effect is more pronounced in relatively small localities. There is a temporal dimension to this effect—that is, turnout drops mainly in the first election after the first merger, but not so much after the second or third merger. Hence, the study provides a skeptical yet differentiated perspective on the democratic consequences of municipal mergers and points to further research avenues to develop a more comprehensive understanding of local government consolidation.  相似文献   
26.
Although parental compliance with court orders in child welfare cases is key to achieving physical parent‐child reunification and successful case closure, little research has examined how parent‐child relationship‐focused rehabilitative services uniquely influence case outcomes. This project fills this gap by investigating links between court ordering of and parental participation in Child‐Parent Psychotherapy (CPP) with court outcomes. Data were obtained from court records of 448 court‐involved parents. Hierarchical regressions revealed that greater participation in CPP led to reunification and successful case closure but not faster case closure. Courtroom professionals should consider parent‐child relationship‐based therapies as tools for achieving child welfare goals.  相似文献   
27.
为建立牛乳中酮洛芬的液相色谱-串联质谱(LC-MS/MS)检测方法,牛乳样品经甲醇提取,C18色谱柱分离,采用正离子模式,多反应监测,内标法定量。结果表明,牛乳中酮洛芬的检出限为1μg/kg,定量限为5μg/kg,在5~200μg/kg范围内线性关系良好,相关系数大于0.99。在25~100μg/kg添加水平的回收率为93.3%~107.5%,批内、批间相对标准偏差分别为1.72%~5.46%、1.13%~7.04%。该方法高效、灵敏、准确,可作为牛乳中酮洛芬的检测方法。选用20头健康的泌乳期荷斯坦乳牛,高产、低产各10头,以3 mg/kg剂量肌内注射给药,每天1次,连用3 d,分别于每次给药后第2、15小时采集乳样。每次给药后2 h牛乳中可检出酮洛芬,最高质量分数为(38.43±3.90)μg/kg,停药后15 h均未检出。所有时间点牛乳中酮洛芬质量分数的实测结果均低于加拿大规定的最高残留限量50μg/kg,建议弃乳期为0 d。  相似文献   
28.
Healthy eating is high on the government's agenda in current times and to all intents and purposes the media appears to have played a crucial role in putting it there. While media focus is no doubt intense and playing a vital role in public education (take Jamie Oliver's 2005 Channel 4 documentary, ‘School dinners’, for example), the question that lies at the heart of this article, is whether the media has led the government agenda on healthy eating and school dinners as appears to be the case. A close examination of the evidence suggests otherwise: government policy was already well set before the media began to show a concerted interest and hence its influence on policy‐making is more limited than might be expected. Rather than setting agendas per se, the media's role has been to refine and energise existing policy areas and to facilitate implementation.  相似文献   
29.
The literature on public‐private partnerships (PPP) has proliferated in recent years. However, confusion about the actual meaning of PPP still abounds. As a consequence, contradicting findings and statements about PPP flourish in the literature. This article reviews the literature, and argues that there are different streams of PPP research which operate with qualitatively different notions of the PPP concept. Accordingly the literature is divided into four different PPP ‘approaches’. By doing so the article offers some clarification concerning an increasingly complex concept. The article concludes that an authoritative definition of PPP – one that can encompass all the different variations of the concept currently in use – is not logically possible.  相似文献   
30.
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.  相似文献   
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