全文获取类型
收费全文 | 699588篇 |
免费 | 29085篇 |
国内免费 | 493篇 |
专业分类
耳鼻咽喉 | 7781篇 |
儿科学 | 23349篇 |
妇产科学 | 15441篇 |
基础医学 | 108480篇 |
口腔科学 | 13831篇 |
临床医学 | 60471篇 |
内科学 | 125221篇 |
皮肤病学 | 12507篇 |
神经病学 | 49966篇 |
特种医学 | 28467篇 |
外国民族医学 | 53篇 |
外科学 | 106111篇 |
综合类 | 9890篇 |
现状与发展 | 2篇 |
一般理论 | 107篇 |
预防医学 | 56111篇 |
眼科学 | 14617篇 |
药学 | 50537篇 |
1篇 | |
中国医学 | 1748篇 |
肿瘤学 | 44475篇 |
出版年
2019年 | 3899篇 |
2018年 | 27128篇 |
2017年 | 21013篇 |
2016年 | 23935篇 |
2015年 | 6212篇 |
2014年 | 7836篇 |
2013年 | 11181篇 |
2012年 | 22258篇 |
2011年 | 37823篇 |
2010年 | 28245篇 |
2009年 | 20038篇 |
2008年 | 34710篇 |
2007年 | 38581篇 |
2006年 | 17374篇 |
2005年 | 18297篇 |
2004年 | 19103篇 |
2003年 | 19435篇 |
2002年 | 17166篇 |
2001年 | 22673篇 |
2000年 | 23356篇 |
1999年 | 19063篇 |
1998年 | 5419篇 |
1997年 | 4557篇 |
1996年 | 4470篇 |
1995年 | 4216篇 |
1992年 | 14440篇 |
1991年 | 15896篇 |
1990年 | 16067篇 |
1989年 | 15698篇 |
1988年 | 14357篇 |
1987年 | 14235篇 |
1986年 | 13188篇 |
1985年 | 12714篇 |
1984年 | 9410篇 |
1983年 | 8018篇 |
1982年 | 4201篇 |
1979年 | 8939篇 |
1978年 | 6390篇 |
1977年 | 5152篇 |
1976年 | 5512篇 |
1975年 | 6618篇 |
1974年 | 7436篇 |
1973年 | 7159篇 |
1972年 | 6597篇 |
1971年 | 6309篇 |
1970年 | 5905篇 |
1969年 | 5487篇 |
1968年 | 5176篇 |
1967年 | 4621篇 |
1966年 | 3965篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
22.
23.
Xiaoyan Lu Isabelle R. Miousse Sandra V. Pirela Jodene K. Moore Stepan Melnyk 《Nanotoxicology》2016,10(5):629-639
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs. 相似文献
24.
C. Dessinioti C.C. Zouboulis V. Bettoli D. Rigopoulos 《Journal of the European Academy of Dermatology and Venereology》2020,34(10):2229-2240
Guidelines and consensus on the management of patients with acne aim to give evidence-based, expert-group recommendations. This review compares current guidelines and consensus articles to provide a compilation of recommendations on the treatment of acne with oral isotretinoin. Ten common, relevant, clinical questions are addressed, based on published recommendations, including the indications of isotretinoin, the proposed daily dose, the cumulative isotretinoin dose and the laboratory monitoring needed. Recommendations on special considerations are also addressed, including the timing of procedures and the question of an association of depression or inflammatory bowel disease with isotretinoin. A major limitation is the use of different classification systems for acne across guidelines. The recommended daily dose ranges from 0.3 to 0.5 mg/kg in the European guidelines to up to 1 mg/kg in the US guidelines. A specific duration of treatment of at least 6 months is only recommended in the European guidelines. All guidelines report the need of strict pregnancy prevention measures. The European, French and US guidelines recommend to monitor for symptoms of depression. Important clinical questions that are inconsistently addressed in guidelines include the age indication, the recommendation for a cumulative dose, the timing of procedures, the association of isotretinoin with IBD, the recommendation for preventing acne flares and for appropriate laboratory monitoring. These topics should be clearly included in the recommendations of guidelines as they are often raised in everyday clinical practice. 相似文献
25.
26.
N. S. Hari Narayana Moorthy Sergio F. Sousa Maria J. Ramos Pedro A. Fernandes 《Medicinal chemistry research》2016,25(7):1340-1357
Farnesyltransferase (FTase) is one of the prenyltransferase family enzymes that catalyse the transfer of 15-membered isoprenoid (farnesyl) moiety to the cysteine of CAAX motif-containing proteins including Rho and Ras family of G proteins. Inhibitors of FTase act as drugs for cancer, malaria, progeria and other diseases. In the present investigation, we have developed two structure-based pharmacophore models from protein–ligand complex (3E33 and 3E37) obtained from the protein data bank. Molecular dynamics (MD) simulations were performed on the complexes, and different conformers of the same complex were generated. These conformers were undergone protein–ligand interaction fingerprint (PLIF) analysis, and the fingerprint bits have been used for structure-based pharmacophore model development. The PLIF results showed that Lys164, Tyr166, TrpB106 and TyrB361 are the major interacting residues in both the complexes. The RMSD and RMSF analyses on the MD-simulated systems showed that the absence of FPP in the complex 3E37 has significant effect in the conformational changes of the ligands. During this conformational change, some interactions between the protein and the ligands are lost, but regained after some simulations (after 2 ns). The structure-based pharmacophore models showed that the hydrophobic and acceptor contours are predominantly present in the models. The pharmacophore models were validated using reference compounds, which significantly identified as HITs with smaller RMSD values. The developed structure-based pharmacophore models are significant, and the methodology used in this study is novel from the existing methods (the original X-ray crystallographic coordination of the ligands is used for the model building). In our study, along with the original coordination of the ligand, different conformers of the same complex (protein–ligand) are used. It concluded that the developed methodology is significant for the virtual screening of novel molecules on different targets. 相似文献
27.
Stelter K. Theodoraki M. N. Becker S. Tsekmistrenko V. Olzowy B. Ledderose G. 《European archives of oto-rhino-laryngology》2015,272(3):639-639
European Archives of Oto-Rhino-Laryngology - 相似文献
28.
29.
Valerie Iles 《Health care analysis》2016,24(2):105-118
This paper takes a somewhat slant perspective on flourishing and care in the context of suffering, death and dying, arguing that care in this context consists principally of ‘acts of work and courage that enable flourishing’. Starting with the perception that individuals, society and health care professionals have become dulled to death and the process of dying in Western advanced health systems, it suggests that for flourishing to occur, both of these aspects of life need to be faced more directly. The last days of life need to be ‘undulled’. Reflections upon the experiences of the author as carer and daughter in the face of her mother’s experience of death are used as basis for making suggestions about how care systems and professionals might better assist people in dealing with ‘the most grown up thing’ humans ever do, which is to die. 相似文献
30.