全文获取类型
收费全文 | 7205篇 |
免费 | 498篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 61篇 |
儿科学 | 163篇 |
妇产科学 | 77篇 |
基础医学 | 1119篇 |
口腔科学 | 71篇 |
临床医学 | 841篇 |
内科学 | 1937篇 |
皮肤病学 | 131篇 |
神经病学 | 627篇 |
特种医学 | 241篇 |
外科学 | 1035篇 |
综合类 | 21篇 |
预防医学 | 532篇 |
眼科学 | 45篇 |
药学 | 382篇 |
中国医学 | 9篇 |
肿瘤学 | 448篇 |
出版年
2023年 | 31篇 |
2022年 | 48篇 |
2021年 | 190篇 |
2020年 | 102篇 |
2019年 | 175篇 |
2018年 | 195篇 |
2017年 | 118篇 |
2016年 | 129篇 |
2015年 | 192篇 |
2014年 | 265篇 |
2013年 | 329篇 |
2012年 | 540篇 |
2011年 | 521篇 |
2010年 | 313篇 |
2009年 | 278篇 |
2008年 | 476篇 |
2007年 | 479篇 |
2006年 | 468篇 |
2005年 | 474篇 |
2004年 | 451篇 |
2003年 | 447篇 |
2002年 | 422篇 |
2001年 | 85篇 |
2000年 | 88篇 |
1999年 | 115篇 |
1998年 | 109篇 |
1997年 | 62篇 |
1996年 | 56篇 |
1995年 | 58篇 |
1994年 | 52篇 |
1993年 | 23篇 |
1992年 | 41篇 |
1991年 | 42篇 |
1990年 | 49篇 |
1989年 | 42篇 |
1988年 | 40篇 |
1987年 | 33篇 |
1986年 | 24篇 |
1985年 | 16篇 |
1984年 | 17篇 |
1983年 | 10篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1975年 | 8篇 |
1973年 | 11篇 |
1970年 | 11篇 |
1967年 | 7篇 |
排序方式: 共有7740条查询结果,搜索用时 15 毫秒
101.
Laura L. Wuyts Michael Camerlinck Didier De Surgeloose Liesbet Vermeiren David Ceulemans Johan Clukers Hans Slabbynck 《The British journal of radiology》2021,94(1120)
Objectives:To determine whether the revised 2018 ATS/ERS/JRS/ALAT radiological criteria for usual interstitial pneumonia (UIP) provide better diagnostic agreement compared to the 2011 guidelines.Methods:Cohort for this cross-sectional study (single center, nonacademic) was recruited from a multidisciplinary team discussion (MDD) from July 2010 until November 2018, with clinical suspicion of fibrosing interstitial lung disease (n= 325). Exclusion criteria were technical HRCT issues, known connective tissue disease (rheumatoid arthritis, systemic sclerosis, poly-or dermatomyositis), exposure to pulmonary toxins or lack of working diagnosis after MDD. Four readers with varying degrees in HRCT interpretation independently categorized 192 HRCTs, according to both the previous and current ATS/ERS/JRS/ALAT radiological criteria. An inter-rater variability analysis (Gwet’s second-order agreement coefficient, AC2) was performed.Results:The resulting Gwet’s AC2 for the 2011 and 2018 ATS/ERS/JRS/ALAT radiological criteria is 0.62 (±0.05) and 0.65 (±0.05), respectively. We report only minor differences in agreement level among the readers. Distribution according to the 2011 guidelines is as follows: 57.3% ‘UIP pattern’, 24% ‘possible UIP pattern’, 18.8% ‘inconsistent with UIP pattern’ and for the 2018 guidelines: 59.6% ‘UIP’, 14.5% ‘probable UIP’, 15.9% ‘indeterminate for UIP’ and 10% ‘alternative diagnosis’.Conclusions:No statistically significant higher degree of diagnostic agreement is observed when applying the revised 2018 ATS/ERS/JRS/ALAT radiological criteria for UIP compared to those of 2011. The inter-rater variability for categorizing the HRCT patterns is moderate for both classification systems, independent of experience in HRCT interpretation. The major advantage of the current guidelines is the better subdivision in the categories with a lower diagnostic certainty for UIP.Advances in knowledge:- In 2018, a revision of the 2011 ATS/ERS/JRS/ALAT radiological criteria for UIP was published, part of diagnostic guidelines for idiopathic pulmonary fibrosis.- The inter-rater agreement among radiologist is moderate for both classification systems, without a significantly higher degree of agreement when applying the revised radiological criteria. 相似文献
102.
Pu Xiao Frédéric Dumur Mohamad‐Ali Tehfe Bernadette Graff Jean Pierre Fouassier Didier Gigmes Jacques Lalevée 《Macromolecular chemistry and physics.》2013,214(15):1749-1755
New photoinitiating systems based on a polyoxometalate (POM) are proposed: phosphomolybdic acid in combination with silane, germane, or iodonium salt can be used to generate silyl, germyl, or phenyl radicals as well as silylium cations. The photochemical mechanisms are studied by steady‐state photolysis and electron spin resonance. The phosphomolybdic acid/silane/iodonium salt system can initiate either the radical photopolymerization of acrylates or the cationic photopolymerization of epoxides. The synthesis of interpenetrated polymer networks can also be carried out. The mechanical properties of the synthesized polymers are affected by the presence of POM in the matrix, as shown by their dynamic mechanical analysis (DMA).
103.
104.
Alessandro Sorrentino Antonino Cataldo Riccardo Curatolo Pietro Tagliatesta Luciana Mosca Stefano Bellucci 《RSC advances》2020,10(48):28941
A valid option to bypass the obstacle represented by the blood–brain barrier (BBB) in brain delivery is the use of the unconventional intranasal route of administration. The treatment of depressive diseases, resulting from the depletion of a neurotransmitter in the inter-synaptic space, such as serotonin, is indirectly treated using molecules that can permeate the BBB unlike the latter. In the present article, a set of nanovectors were produced using a mucoadhesive biopolymer, i.e. alginate (Alg). Optimizing the reaction, polymeric nanoparticles having diameter of 30–70 nm were produced, and water stable multi-walled carbon nanotubes functionalized (MWCNT-COOH)/Alg complexes were obtained. These nanovectors were loaded with serotonin, evaluating drug loading/release. By means of Raman microscopy, the cellular internalization of the (MWCNT-COOH)/Alg complex was demonstrated. A complete biocompatibility on neuronal cells was proved for the whole set of nanovectors. Finally, a method of self-administration was tested, which involves the use of a household apparatus, such as an aerosol machine, observing a fine particulate, able to deliver the nanovectors through the nose.A valid option to bypass the obstacle represented by the blood–brain barrier (BBB) in brain delivery is the use of the unconventional intranasal route of administration. 相似文献
105.
Rachid Sani Samuila Sanoussi James Lassey Didier Garba Mohamed Salifou Habibou Abarchi 《The Indian journal of surgery》2015,77(3):822-826
The purpose of the study was to evaluate the qualitative aspect and global impact of surgery in a district hospital (DH) since the launching of the surgery at the district level. Surgical care was provided by general practitioners (GP) who received 12-month training in surgery, certified by a “Capacity of District Surgery” (CDS) diploma. It was a prospective study during 4 years from 2007 to 2010. Of the 34 DHs, only 21 were functional and included in this study. Most of the DHs had two or more CDS (n?=?15). The majority of the DHs had one nurse surgical aid (n?=?16) and one nurse anesthetist (n?=?17). The total number of surgical operations was 18,441 cases; emergency cases represented 51.8 % and elective surgery 48.2 %. Regarding emergency surgery, cesarean sections revealed the most common surgical procedure (37.21 %), followed by wound debridement (19.42 %). In elective surgery, hernia repair and hydrocelectomy were the most common surgical procedures (69.60 %), followed by gynecologic procedures in 12.74 % of the cases. The global complication rate was 4.34 %. The global mortality rate was 1.04 % (n?=?192), 102 deaths following cesarean section (2.87 %). No death was encountered in elective surgery. Nine hundred and fifty-five patients (5.17 %) were transferred to a higher-level facility of whom 598 patients (62.61 %) were admitted for fracture treatment. The concept of district surgery has proven to be an effective tool to counter skilled medical manpower shortage to perform emergency and elective basic surgery at the rural level and could be adopted by developing countries facing similar health challenges. 相似文献
106.
107.
Renesto P Crapoulet N Ogata H La Scola B Vestris G Claverie JM Raoult D 《Lancet》2003,362(9382):447-449
Empirical approaches have guided the development of bacterial cultures. The availability of sequenced genomes now provides opportunities to define culture media for growth of fastidious pathogens with computer modelling of metabolic networks. A key issue is the possibility of growing host-dependent bacteria in cell-free conditions. The sequenced Tropheryma whipplei genome was analysed to identify specific metabolic deficiencies. We used this information to design a comprehensive medium that allowed three established T whipplei strains from culture with human cells and one new strain from a clinical sample to grow axenically. Genomic information can, therefore, provide sufficient clues for designing axenic media for fastidious and uncultured pathogens. 相似文献
108.
Shengfu Li Bruno Montcel Zhen Yuan Wanyu Liu Didier Vray 《Biomedical optics express》2015,6(7):2424-2434
This paper proposes a multigrid inversion framework for quantitative photoacoustic tomography reconstruction. The forward model of optical fluence distribution and the inverse problem are solved at multiple resolutions. A fixed-point iteration scheme is formulated for each resolution and used as a cost function. The simulated and experimental results for quantitative photoacoustic tomography reconstruction show that the proposed multigrid inversion can dramatically reduce the required number of iterations for the optimization process without loss of reliability in the results.OCIS codes: (170.3880) Medical and biological imaging, (170.5120) Photoacoustic imaging, (170.6960) Tomography 相似文献
109.
110.
Didier M. Payen Joelle Guilhot Yoann Launey Anne Claire Lukaszewicz Mahmoud Kaaki Benoit Veber Julien Pottecher Olivier Joannes-Boyau Laurent Martin-Lefevre Matthieu Jabaudon Olivier Mimoz Rémi Coudroy Martine Ferrandière Eric Kipnis Carlos Vela Stéphanie Chevallier Jihad Mallat René Robert The ABDOMIX Group 《Intensive care medicine》2015,41(6):975-984