全文获取类型
收费全文 | 25079篇 |
免费 | 2315篇 |
国内免费 | 70篇 |
专业分类
耳鼻咽喉 | 260篇 |
儿科学 | 575篇 |
妇产科学 | 343篇 |
基础医学 | 3063篇 |
口腔科学 | 796篇 |
临床医学 | 3246篇 |
内科学 | 5368篇 |
皮肤病学 | 611篇 |
神经病学 | 1853篇 |
特种医学 | 1039篇 |
外科学 | 3534篇 |
综合类 | 456篇 |
一般理论 | 24篇 |
预防医学 | 2661篇 |
眼科学 | 352篇 |
药学 | 1981篇 |
中国医学 | 23篇 |
肿瘤学 | 1279篇 |
出版年
2021年 | 360篇 |
2020年 | 204篇 |
2019年 | 347篇 |
2018年 | 370篇 |
2017年 | 270篇 |
2016年 | 333篇 |
2015年 | 379篇 |
2014年 | 520篇 |
2013年 | 822篇 |
2012年 | 1122篇 |
2011年 | 1115篇 |
2010年 | 621篇 |
2009年 | 574篇 |
2008年 | 1030篇 |
2007年 | 1039篇 |
2006年 | 1076篇 |
2005年 | 1090篇 |
2004年 | 1018篇 |
2003年 | 971篇 |
2002年 | 969篇 |
2001年 | 976篇 |
2000年 | 1003篇 |
1999年 | 843篇 |
1998年 | 312篇 |
1997年 | 265篇 |
1996年 | 251篇 |
1995年 | 254篇 |
1994年 | 209篇 |
1993年 | 216篇 |
1992年 | 608篇 |
1991年 | 629篇 |
1990年 | 588篇 |
1989年 | 527篇 |
1988年 | 493篇 |
1987年 | 487篇 |
1986年 | 483篇 |
1985年 | 481篇 |
1984年 | 342篇 |
1983年 | 299篇 |
1982年 | 226篇 |
1981年 | 206篇 |
1979年 | 328篇 |
1978年 | 244篇 |
1977年 | 205篇 |
1975年 | 168篇 |
1974年 | 214篇 |
1973年 | 204篇 |
1972年 | 169篇 |
1971年 | 192篇 |
1970年 | 170篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
Eric E Rasmussen Autumn Shafer Malinda J. Colwell Shawna White Narissra Punyanunt-Carter Rebecca L. Densley 《Journal of Children and Media》2016,10(4):443-461
This study explored the relationship between active mediation, exposure to Daniel Tiger’s Neighborhood, and key indicators of preschoolers’ social and emotional development. One hundred and twenty-seven children aged 2–6 either watched or did not watch 10 episodes of Daniel Tiger’s Neighborhood over a two-week period. Results revealed that preschoolers who watched the program exhibited higher levels of empathy, self-efficacy, and emotion recognition when their regular TV-watching experiences are frequently accompanied by active mediation. This was especially true for younger preschoolers and preschoolers from low-income families. Implications for policy-makers, parents, producers of prosocial programming, and educators are discussed. 相似文献
3.
4.
Auda A. Eltahla Fabio Luciani Peter A. White Andrew R. Lloyd Rowena A. Bull 《Viruses》2015,7(10):5206-5224
The hepatitis C virus (HCV) is a pandemic human pathogen posing a substantial health and economic burden in both developing and developed countries. Controlling the spread of HCV through behavioural prevention strategies has met with limited success and vaccine development remains slow. The development of antiviral therapeutic agents has also been challenging, primarily due to the lack of efficient cell culture and animal models for all HCV genotypes, as well as the large genetic diversity between HCV strains. On the other hand, the use of interferon-α-based treatments in combination with the guanosine analogue, ribavirin, achieved limited success, and widespread use of these therapies has been hampered by prevalent side effects. For more than a decade, the HCV RNA-dependent RNA polymerase (RdRp) has been targeted for antiviral development. Direct acting antivirals (DAA) have been identified which bind to one of at least six RdRp inhibitor-binding sites, and are now becoming a mainstay of highly effective and well tolerated antiviral treatment for HCV infection. Here we review the different classes of RdRp inhibitors and their mode of action against HCV. Furthermore, the mechanism of antiviral resistance to each class is described, including naturally occurring resistance-associated variants (RAVs) in different viral strains and genotypes. Finally, we review the impact of these RAVs on treatment outcomes with the newly developed regimens. 相似文献
5.
6.
Nishard Abdeen Albert Cross Gregory Cron Steven White Thomas Rand David Miller Giles Santyr 《Magnetic resonance in medicine》2006,56(2):255-264
We used the dual capability of hyperpolarized 129Xe for spectroscopy and imaging to develop new measures of xenon diffusing capacity in the rat lung that (analogously to the diffusing capacity of carbon monoxide or DLCO) are calculated as a product of total lung volume and gas transfer rate constants divided by the pressure gradient. Under conditions of known constant pressure breath-hold, the volume is measured by hyperpolarized 129Xe MRI, and the transfer rate is measured by dynamic spectroscopy. The new quantities (xenon diffusing capacity in lung parenchyma (DLXeLP)), xenon diffusing capacity in RBCs (DLXeRBC), and total lung xenon diffusing capacity (DLXe)) were measured in six normal rats and six rats with lung inflammation induced by instillation of fungal spores of Stachybotrys chartarum. DLXeLP, DLXeRBC, and DLXe were 56 +/- 10 ml/min/mmHg, 64 +/- 35 ml/min/mmHg, and 29 +/- 9 ml/min/mmHg, respectively, for normal rats, and 27 +/- 9 ml/min/mmHg, 42 +/- 27 ml/min/mmHg, and 16 +/- 7 ml/min/mmHg, respectively, for diseased rats. Lung volumes and gas transfer times for LP (TtrLP) were 16 +/- 2 ml and 22 +/- 3 ms, respectively, for normal rats and 12 +/- 2 ml and 35 +/- 8 ms, respectively, for diseased rats. Xenon diffusing capacities may be useful for measuring changes in gas exchange associated with inflammation and other lung diseases. 相似文献
7.
8.
9.
Clinical decisions are often made with incomplete information, yet patient care decisions are made every day. Patients vary clinically, uncertainty exists in diagnostic and prognostic information, and many preventive and treatment alternatives have not been formally assessed for their effectiveness. Because scientific information will never answer all clinical questions, clinical decisions are partially based on probabilistic information.
This paper describes how to apply clinical decision making to diagnosing and managing dental caries and periodontal diseases. By using explicit information to quantify probabilities and outcomes, clinical decision making analyzes decisions made under uncertain conditions and the uncertain impact of clinical information.
Clinical decision making incorporates concepts for preventing, diagnosing and treating dental caries and periodontal diseases: risk assessment, evidence-based dentistry, and multiple oral health outcomes. This information can serve as a tool for clinicians to augment clinical judgment and expertise. 相似文献
This paper describes how to apply clinical decision making to diagnosing and managing dental caries and periodontal diseases. By using explicit information to quantify probabilities and outcomes, clinical decision making analyzes decisions made under uncertain conditions and the uncertain impact of clinical information.
Clinical decision making incorporates concepts for preventing, diagnosing and treating dental caries and periodontal diseases: risk assessment, evidence-based dentistry, and multiple oral health outcomes. This information can serve as a tool for clinicians to augment clinical judgment and expertise. 相似文献
10.