全文获取类型
收费全文 | 190778篇 |
免费 | 13738篇 |
国内免费 | 4423篇 |
专业分类
耳鼻咽喉 | 1382篇 |
儿科学 | 2912篇 |
妇产科学 | 3141篇 |
基础医学 | 25788篇 |
口腔科学 | 3446篇 |
临床医学 | 13409篇 |
内科学 | 26321篇 |
皮肤病学 | 3461篇 |
神经病学 | 12221篇 |
特种医学 | 6563篇 |
外国民族医学 | 1篇 |
外科学 | 15272篇 |
综合类 | 25521篇 |
现状与发展 | 21篇 |
一般理论 | 8篇 |
预防医学 | 15133篇 |
眼科学 | 2372篇 |
药学 | 25872篇 |
55篇 | |
中国医学 | 12801篇 |
肿瘤学 | 13239篇 |
出版年
2024年 | 340篇 |
2023年 | 2417篇 |
2022年 | 4985篇 |
2021年 | 7890篇 |
2020年 | 6382篇 |
2019年 | 6437篇 |
2018年 | 6464篇 |
2017年 | 7044篇 |
2016年 | 7110篇 |
2015年 | 6661篇 |
2014年 | 7628篇 |
2013年 | 11917篇 |
2012年 | 9345篇 |
2011年 | 11325篇 |
2010年 | 7179篇 |
2009年 | 7373篇 |
2008年 | 8863篇 |
2007年 | 9897篇 |
2006年 | 9385篇 |
2005年 | 8656篇 |
2004年 | 7506篇 |
2003年 | 6686篇 |
2002年 | 5308篇 |
2001年 | 4769篇 |
2000年 | 4006篇 |
1999年 | 3443篇 |
1998年 | 2668篇 |
1997年 | 2751篇 |
1996年 | 2522篇 |
1995年 | 2191篇 |
1994年 | 2129篇 |
1993年 | 1801篇 |
1992年 | 1650篇 |
1991年 | 1561篇 |
1990年 | 1359篇 |
1989年 | 1085篇 |
1988年 | 1050篇 |
1987年 | 950篇 |
1986年 | 876篇 |
1985年 | 1267篇 |
1984年 | 1018篇 |
1983年 | 756篇 |
1982年 | 789篇 |
1981年 | 642篇 |
1980年 | 615篇 |
1979年 | 488篇 |
1978年 | 309篇 |
1977年 | 270篇 |
1976年 | 247篇 |
1975年 | 190篇 |
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
11.
《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections. 相似文献
12.
13.
14.
15.
Xiying Fan Glen A. Bjerke Kent Riemondy Li Wang Rui Yi 《Molecular carcinogenesis》2019,58(12):2241-2253
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer. 相似文献
16.
This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.
The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same. 相似文献
17.
18.
19.
《Journal of Evidence》2019,19(2):131-139
ObjectivesThe aims of this article are to identify all the published systematic reviews (SRs) and meta-analyses (MAs) that studied the relationship between periodontal and systemic diseases and to assess their quality using 2 scales (the Overview Quality Assessment Questionnaire [OQAQ] and A Measurement Tool to Assess Systematic Reviews [AMSTAR] checklist).MethodsFor SRs and MAs to be included, they should have investigated one of the following systemic diseases: pulmonary conditions, cardiac conditions, endocrine conditions, cancer, blood disorders, psychological conditions, anxiety, depression, mood disorders, and several other diseases. Two investigators screened MEDLINE via PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews. The tools used to evaluate quality were the AMSTAR scale and OQAQ. The protocol was prospectively registered in PROSPERO (CRD42018102208).ResultsThe search strategy found 691 unique articles, 42 of which met the eligibility criteria and were included in this review. Diabetes mellitus was the most investigated disease (14 out of 42 studies), followed by obesity (11 studies) and cardiovascular diseases (5 studies). A total of 40 reviews reported on the characteristics of included studies, and, as per the AMSTAR scale, 39 reviews had an a priori design. The number of reviews that fulfilled the status of publication criterion was the lowest (7 reviews only), followed by the number used in the assessment of publication bias (11 reviews). The number of high-quality reviews was higher with the OQAQ than with the AMSTAR checklist (33 vs 25 studies), but the AMSTAR showed a higher number of medium-quality reviews than the OQAQ (14 vs 6 studies). Both showed the same number of low-quality reviews.ConclusionsHigh-quality SRs and MAs are crucial to understanding the relationship between systemic and periodontal diseases. Medical practitioners must be able to inform patients about oral health and specific periodontal health concerns. 相似文献
20.