全文获取类型
收费全文 | 5791篇 |
免费 | 135篇 |
专业分类
各国政治 | 248篇 |
工人农民 | 229篇 |
世界政治 | 464篇 |
外交国际关系 | 210篇 |
法律 | 3630篇 |
中国政治 | 49篇 |
政治理论 | 1078篇 |
综合类 | 18篇 |
出版年
2021年 | 41篇 |
2020年 | 69篇 |
2019年 | 105篇 |
2018年 | 134篇 |
2017年 | 117篇 |
2016年 | 123篇 |
2015年 | 70篇 |
2014年 | 121篇 |
2013年 | 599篇 |
2012年 | 143篇 |
2011年 | 156篇 |
2010年 | 123篇 |
2009年 | 141篇 |
2008年 | 168篇 |
2007年 | 160篇 |
2006年 | 143篇 |
2005年 | 130篇 |
2004年 | 161篇 |
2003年 | 124篇 |
2002年 | 103篇 |
2001年 | 311篇 |
2000年 | 278篇 |
1999年 | 191篇 |
1998年 | 76篇 |
1997年 | 77篇 |
1996年 | 51篇 |
1995年 | 56篇 |
1994年 | 50篇 |
1993年 | 41篇 |
1992年 | 123篇 |
1991年 | 140篇 |
1990年 | 133篇 |
1989年 | 126篇 |
1988年 | 114篇 |
1987年 | 125篇 |
1986年 | 101篇 |
1985年 | 96篇 |
1984年 | 98篇 |
1983年 | 83篇 |
1982年 | 57篇 |
1981年 | 73篇 |
1980年 | 34篇 |
1979年 | 73篇 |
1978年 | 43篇 |
1975年 | 37篇 |
1974年 | 49篇 |
1973年 | 54篇 |
1972年 | 39篇 |
1971年 | 34篇 |
1970年 | 29篇 |
排序方式: 共有5926条查询结果,搜索用时 15 毫秒
1.
Natur und Recht - Planfeststellung und Plangenehmigung sind etablierte Instrumente der Vorhabenzulassung und für den Gewässerausbau bereits seit langem auch im Wasserhaushaltsrecht... 相似文献
2.
Levey Emma K. V. Garandeau Claire F. Meeus Wim Branje Susan 《Journal of youth and adolescence》2019,48(6):1068-1081
Journal of Youth and Adolescence - Adolescence tends to be characterized by a temporary peak in delinquent behavior, and friends in particular play a key role in the initiation and the development... 相似文献
3.
Asia Europe Journal - This article examines the role of strategic partnerships in Indian foreign policy and the nature and perceptions of India and the European Union about the strategic... 相似文献
4.
Folk Johanna B. Brown Larry K. Marshall Brandon D. L. Ramos Lili M. C. Gopalakrishnan Lakshmi Koinis-Mitchell Daphne Tolou-Shams Marina 《Journal of youth and adolescence》2020,49(1):238-251
Journal of Youth and Adolescence - Court-involved youth exhibit high rates of psychiatric symptoms, substance use, and delinquency, yet little is known about the contributing roles of caregiver and... 相似文献
5.
Christina Mancini Amy K. Cook Jessica C. Smith Robyn McDougle 《Journal of school violence》2020,19(4):610-622
ABSTRACT Recently, states have enacted teacher-carry laws. While controversial, little scholarship has tapped public attitudes toward such reforms. Because public opinion shapes policy, the public is an important stakeholder in this debate. Thus, we investigated three questions. First, how supportive is the public of arming teachers? Second, what demographic and social divides exist, if any, for reform approval? Finally, do crime-related perceptions, concerning views about public safety, and criminogenic influences shape policy preferences? We test these questions using a 2018 poll of Virginia residents (N = 521). Overall, approval for teacher-carry is split. Crime-related perceptions mediate some of the initial social and demographic divides in opinion but other correlates, such as parental status, remain salient predictors of views. Implications are discussed. 相似文献
6.
Victoria S. Kwol Turgay Avci Kayode K. Eluwole Angela Dalhatu 《Journal of Public Affairs (14723891)》2020,20(3)
Food handlers are essential in the fight for the prevention of foodborne disease outbreaks as they are critical in ensuring the delivery of safe and healthy food to the consumers. The current study build on knowledge, attitude, and practice model (KAP) to investigate the impact of food handlers' knowledge and attitude on the hygienic‐sanitary conditions of food delivered to the consumers in Nigerian hospitality sector. Using data collected from food handlers in restaurants, hotels and hospitals in Jos metropolis of Nigeria, the study revealed that handlers applied food safety measures to the level of their knowledge. Further investigation revealed that KAP model works effectively in the case of food handlers in Jos. We conclude with recommendations for the industry and education institutes where handlers are trained. 相似文献
7.
R. J. Mourits N. van den Berg M. Rodríguez-Girondo K. Mandemakers P. E. Slagboom M. Beekman 《The History of the Family》2020,25(3):484-526
ABSTRACT Studies have shown that long-lived individuals seem to pass their survival advantage on to their offspring. Offspring of long-lived parents had a lifelong survival advantage over individuals without long-lived parents, making them more likely to become long-lived themselves. We test whether the survival advantage enjoyed by offspring of long-lived individuals is explained by environmental factors. 101,577 individuals from 16,905 families in the 1812–1886 Zeeland cohort were followed over time. To prevent that certain families were overrepresented in our data, disjoint family trees were selected. Offspring was included if the age at death of both parents was known. Our analyses show that multiple familial resources are associated with survival within the first 5 years of life, with stronger maternal than paternal effects. However, between ages 5 and 100 both parents contribute equally to offspring’s survival chances. After age 5, offspring of long-lived fathers and long-lived mothers had a 16-19% lower chance of dying at any given point in time than individuals without long-lived parents. This survival advantage is most likely genetic in nature, as it could not be explained by other, tested familial resources and is transmitted equally by fathers and mothers. 相似文献
8.
Kristopher D. Wisniewski Ph.D. Nicholas Cooper M.Sc. Vivienne Heaton Ph.D. Colin Hope B.Sc.; M.Sc. Duncan Pirrie Ph.D. Andrew J. Mitten M.Geo. Jamie K. Pringle Ph.D. 《Journal of forensic sciences》2019,64(5):1530-1539
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations. 相似文献
9.
Sophia K. Chiu M.D. M.P.H. Jessica F. Li M.S.P.H. Kurt B. Nolte M.D. 《Journal of forensic sciences》2020,65(4):1324-1327
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls. 相似文献
10.
Jarman Hannah K. Marques Mathew D. McLean Siân A. Slater Amy Paxton Susan J. 《Journal of youth and adolescence》2021,50(12):2279-2293
Journal of Youth and Adolescence - Adolescents are spending considerable time on social media, yet it is unclear whether motivations for social media use drive different forms of social media... 相似文献