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1.
为建立检测非洲猪瘟病毒(African swine fever virus,ASFV)的快速诊断方法,本研究根据ASFV SY18株p17蛋白的编码基因D117L的保守序列设计并合成引物和探针,建立了基于ASFV p17蛋白的编码基因D117L的TaqMan荧光定量PCR检测方法,并验证其特异性、灵敏性和重复性。结果显示,本研究建立的TaqMan荧光定量PCR检测方法的C_t值与标准品在1×10^9~1×10^1copies/μL范围内呈良好的线性关系,相关系数为0.998,斜率为-3.192,检测下限为10 copies/μL,且与其他能引起相似症状的猪源病毒无交叉反应。重复性试验结果显示,组间与组内变异系数均小于1.920 7%,重复性好。此方法可用于ASF的早期诊断和ASFV快速检测。  相似文献   
2.
Abstract

Most of the literature on state transformation focuses on China’s relations with African, Asian and Latin American countries and the National Oil Companies’ overseas expansion to show that China has become fragmented, decentralised and internationalised. This article contributes novel findings by focusing on China’s relations with Europe and the actions of China’s National Nuclear Companies (NNCs). It shows that NNCs, which have become relatively autonomous actors, often pursue their agendas of expansion into Europe without much coordination with, or even in contradiction to, other ministries’ agendas and interests, especially the Ministry of Foreign Affairs. Instead of being orchestrated by the central government, their expansion reflects considerable disorganisation and sometimes undermines China’s official strategy. The article demonstrates this through case studies of NNCs’ involvement in the UK and Romania.  相似文献   
3.
International research collaboration (IRC) is associated with both positive and negative effects on the performance of research in emerging economies. While some authors claim that North–South collaborations improve scientific quality and visibility for Southern countries, others claim that it may entail the reorientation of research to comply with Northern agendas. South–South collaborations are thought to increase the focus on local affairs, therefore leading to a relatively small number of scientific international publications appearing in “high quality” journals. Research on the impact of IRC beyond publications in international journals has been neglected despite the importance of other products in knowledge creation. This research uses a broad range of scientific outputs to empirically assess such assumptions and explore the outcomes of IRC in Colombia. Results from multivariate regressions and nonparametric analyses show that, contrary to common assumptions, Colombian research teams collaborating with partners from the global South report higher scientific production, while those collaborating with Northern countries seem to contribute to local knowledge the most.  相似文献   
4.
目的 以自发性高血压大鼠(spontaneous hypertensive rat,SHR)为观察对象,探究针刺降压的钟基因调控作用。方法 将24只SHR随机分为针刺组和模型组,12只Wistar-Kyoto(WKY)大鼠作为正常组。针刺组选择辰时针刺SHR双侧曲池、足三里穴,模型组和正常组仅接受与针刺组同等强度的捆绑操作。4周后,各组分别在辰、酉时随机抽取6只大鼠,测量鼠尾收缩压(systolic blood pressure, SBP)和舒张压(diastolic blood pressure, DBP),然后检测血清5-羟色胺(5-hydroxytryptamine,5-HT)、褪黑素(melatonin, MT)的含量以及心脏生物钟基因Clock和Bmal1的表达水平。结果 分组因素对SBP、DBP、血清MT含量、Clock表达结果的RQ值、Bmal1表达结果的RQ值的主效应均有统计学意义(P<0.05),时辰因素对各指标的主效应和两者的交互作用均无统计学意义(P>0.05)。模型组辰、酉两个时辰的SBP和DBP均高于正常组(P<0.05),针刺组辰时的SBP和DBP及酉时的SBP均低于模型组(P<0.05)。模型组辰时MT含量较正常组降低,5-HT含量较正常组升高(P<0.05),针刺组辰时MT含量较模型组升高,5-HT含量较模型组降低(P<0.05);针刺组酉时的MT含量较模型组升高(P<0.05)。针刺组辰时心脏Clock基因表达水平和酉时心脏Bmal1基因表达水平较模型组升高(P<0.05)。结论 辰时针刺可以降低SHR的“双峰”血压,其作用机制可能与提高血清MT含量,减少5-HT含量以及提高心脏Clock和Bmal1基因的表达水平有关。  相似文献   
5.
砂拉越位于婆罗洲,原为文莱属地,1841年白人拉惹政权建立后,大批华人在其招垦下移入砂拉越。在华文教育萌芽的初期,白人拉惹对其取自由放任的态度,直至20世纪20年代,因华人社会中的政治运动及海外华侨民族主义在各个华文学校的发展,才颁布学校注册法令,开始干涉砂拉越地区的华文教育。二战后,白人拉惹将砂拉越让渡给英国,新成立的殖民地政府急于统合境内各族群对砂拉越的认同,遂推动以英语为教学媒介语的国家教育制度,迫使砂拉越华文中等学校在改制成以英语授课的学校或独立中学之间做出选择。为保存族群母语教育,为华族子弟接受母语教育提供机会,在古晋地区创立的中华第一中学,决定成为一间华文独立中学。这间华文独立中学至今仍有千名以上学生,其校园中充满华族文化气息。本文对古晋中华第一中学的创立、发展、经营作一个案研究,期盼对吾人进一步了解战后砂拉越华族社会族群语言的维护及文化的传承有所助益。  相似文献   
6.
Governance scholars have long championed the adaptive utility of decentralized management institutions, in part due to their ability to bring diverse stakeholders into decision‐making processes. However, research into the link between decentralization and participation often looks at policy design but bypasses important system feedbacks that shape sustained participation over time. To paint a more robust picture detailing how decentralization and participation are related, this paper uses a complex systems framework to explore interacting structural, operational, and cultural components of decentralized wildlife governance institutions in the United States and Botswana. Through this comparative analysis, I argue that the landscape of public participation in decentralized governance institutions appears to be significantly impacted by three factors: 1) how decentralization processes occurred, 2) where in the process of decision making participation is situated, and 3) perceptions of power distribution between groups with competing interests.  相似文献   
7.
Among the more recognizable programs related to natural and sustainable food is the United States Department of Agriculture’s National Organic Program. Although the robustness of the organic food market is difficult to contest, many debate the extent to which U.S. organic policy outcomes adequately serve consumers and the organic agriculture producers they rely on. This paper engages the debate from the perspective of certified organic producers. Drawing on the results of a nationwide survey of USDA‐certified producers, we first provide a snapshot of how producers assess the environmental, consumer, and market impacts of U.S. organic food policy. We then examine the extent to which organic producers’ policy impact perceptions are associated with their alignment with an “organic ethos”—understood as producers’ commitment to core organic principles and the organic movement. The paper highlights producers’ values as perceptual filters and cognitive mechanisms that help shape producers’ policy impacts perceptions, illustrating a contributing factor to the enduring nature of organic policy debates.  相似文献   
8.
Self‐driving cars (also known as driverless cars, autonomous vehicles, and highly automated vehicles [HAVs]) will change the regulatory, political, and ethical frameworks surrounding motor vehicles. At the highest levels of automation, HAVs are operated by independent machine agents, making decisions without the direct intervention of humans. The current transportation system assumes human intervention though, including legal and moral responsibilities of human operators. Has the development of these artificial intelligence (AI) and autonomous system (AS) technologies outpaced the ethical and political conversations? This paper examines discussions of HAVs, driver responsibility, and technology failure to highlight the differences between how the policy‐making institutions in the United States (Congress and the Public Administration) and technology and transportation experts are or are not speaking about responsibility in the context of autonomous systems technologies. We report findings from a big data analysis of corpus‐level documents to find that enthusiasm for HAVs has outpaced other discussions of the technology.  相似文献   
9.
Renewable portfolio standards (RPS) are an important policy tool for reducing carbon emissions and advancing the global shift toward renewable energy. As the U.S. federal government backs away from commitments to reduce greenhouse gas emissions, subnational governments play an increasingly important role in mitigating climate change. In June 2015, Hawaii became the first state in the United States to adopt a 100% RPS. Through understanding the conditions that gave rise to Hawaii’s RPS, policy actors will be better informed as they navigate policy processes in other states and jurisdictions. This study uses Kingdon’s Multiple Streams Framework (MSF) to explore the policy process that led to Hawaii’s 100% RPS. Data were collected during the summer of 2016 via interviews with 25 key policy actors and informants in Hawaii. Expectations based on the MSF are confirmed, and the results suggest factors that might be included or explored in future studies of RPS adoption.  相似文献   
10.
The Narrative Policy Framework (NPF) focuses on the role of narratives, drawing from a rich scholarship in narrative, language, and culture. Despite the understanding that narratives are constructions of language and that narrative construction differs across languages, NPF studies have not focused on policy narratives in languages other than English. Language characteristics of narratives are important to assess the stability of policy narratives when there are multiple dominant languages in a political system. This study investigates the use of narrative elements in policy narratives in agricultural biotechnology policy in India across Hindi and English media coverage to examine the NPF assumption that narratives have generalizable narrative elements irrespective of variation in linguistic context and, specifically, tests the transportability of narrative elements. Findings validate the transportability of narrative elements in Hindi narratives, indicate variation in the use of narrative elements over time, and have implications for applying NPF across languages.  相似文献   
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