全文获取类型
收费全文 | 174208篇 |
免费 | 905篇 |
专业分类
耳鼻咽喉 | 1121篇 |
儿科学 | 6605篇 |
妇产科学 | 2988篇 |
基础医学 | 16339篇 |
口腔科学 | 1526篇 |
临床医学 | 12244篇 |
内科学 | 30494篇 |
皮肤病学 | 651篇 |
神经病学 | 16332篇 |
特种医学 | 8876篇 |
外科学 | 28644篇 |
综合类 | 2305篇 |
预防医学 | 18010篇 |
眼科学 | 2718篇 |
药学 | 9373篇 |
中国医学 | 623篇 |
肿瘤学 | 16264篇 |
出版年
2018年 | 21916篇 |
2017年 | 17357篇 |
2016年 | 19499篇 |
2015年 | 873篇 |
2014年 | 760篇 |
2013年 | 713篇 |
2012年 | 6872篇 |
2011年 | 20911篇 |
2010年 | 18758篇 |
2009年 | 11463篇 |
2008年 | 19407篇 |
2007年 | 21603篇 |
2006年 | 449篇 |
2005年 | 2075篇 |
2004年 | 3286篇 |
2003年 | 4260篇 |
2002年 | 2412篇 |
2001年 | 251篇 |
2000年 | 394篇 |
1999年 | 149篇 |
1998年 | 190篇 |
1997年 | 195篇 |
1996年 | 83篇 |
1995年 | 95篇 |
1994年 | 92篇 |
1993年 | 55篇 |
1992年 | 34篇 |
1991年 | 81篇 |
1990年 | 120篇 |
1989年 | 73篇 |
1988年 | 50篇 |
1987年 | 37篇 |
1986年 | 21篇 |
1985年 | 28篇 |
1984年 | 18篇 |
1983年 | 20篇 |
1982年 | 24篇 |
1980年 | 39篇 |
1974年 | 19篇 |
1970年 | 19篇 |
1969年 | 20篇 |
1968年 | 17篇 |
1939年 | 20篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1933年 | 14篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
991.
Setor Kwadzo Kunutsor Michael Richard Whitehouse Ashley William Blom Jari Antero Laukkanen 《European journal of epidemiology》2017,32(7):593-603
Magnesium, which is an essential trace element that plays a key role in several cellular processes, is a major component of bone; however, its relationship with risk of major bone fractures is uncertain. We aimed to investigate the association of baseline serum magnesium concentrations with risk of incident fractures. We analyzed data on 2245 men aged 42–61 years in the Kuopio Ischemic Heart Disease prospective cohort study, with the assessment of serum magnesium measurements and dietary intakes made at baseline. Hazard ratios [95% confidence intervals (CI)] for incident total (femoral, humeral, and forearm) and femoral fractures were assessed. During a median follow-up of 25.6 years, 123 total fractures were recorded. Serum magnesium was non-linearly associated with risk of total fractures. In age-adjusted Cox regression analysis, the hazard ratio (HR) (95% CIs) for total fractures in a comparison of the bottom quartile versus top quartile of magnesium concentrations was 2.10 (1.30–3.41), which persisted on adjustment for several established risk factors 1.99 (1.23–3.24). The association remained consistent on further adjustment for renal function, socioeconomic status, total energy intake, and several trace elements 1.80 (1.10–2.94). The corresponding adjusted HRs for femoral fractures were 2.56 (1.38–4.76), 2.43 (1.30–4.53) and 2.13 (1.13–3.99) respectively. There was no evidence of an association of dietary magnesium intake with risk of any fractures. In middle-aged Caucasian men, low serum magnesium is strongly and independently associated with an increased risk of fractures. Further research is needed to assess the potential relevance of serum magnesium in the prevention of fractures. 相似文献
992.
We report a case of acquired thrombotic thrombocytopenic purpura (TTP) in a 34-year old patient with a prior diagnosis of
systemic lupus erythematosis (SLE) who was recently started on hydroxychloroquine. Presenting symptoms included fevers, sore
throat and productive cough with progressive weakness, dyspnea on exertion, hemoptysis and dark urine. Initial laboratory
abnormalities were consistent with an acute microangiopathic hemolytic anemia and severe thrombocytopenia. At the time of
admission, the patient’s lupus was highly active as evident by his high SLE Disease Activity Index (SLEDAI) score. He was
later also found to have severely reduced ADAMTS-13 levels and a positive antibody assay. This case highlights the occasional
difficulty in pinpointing the exact etiology of TTP as well as establishes a possible novel drug association between hydroxychloroquine
and TTP development. 相似文献
993.
Alastair van Heerden Mark Tomlinson Sarah Skeen Charles Parry Kendal Bryant Mary Jane Rotheram-Borus 《AIDS and behavior》2017,21(2):274-278
Working in an interdisciplinary manner at the crossroads of alcohol and HIV research is a challenge. This paper presents six novel approaches that could be applied to activities at the intersection of alcohol and HIV. These approaches are (i) address the fact that the availability of new technology is unevenly distributed around the world, (ii) use technology to move beyond both paper and digital surveys, (iii) introduce a focus on advocacy and partnerships with large technology companies, (iv) harness technological innovation to utilise digital counselling, (v) explore the use of virtual reality in both research and delivering interventions, and (vi) consider alternative funding models to those currently in existence to improve efficiencies and innovations. Aiming to understand the interplay of alcohol and HIV will require creativity. The six approaches outlines in this paper provide possible directions from which new approaches may emerge. 相似文献
994.
995.
996.
997.
998.
Katia Herz Alexandra Becker Chenyue Shi Masatsugo Ema Satoru Takahashi Michael Potente Michael Hesse Bernd K. Fleischmann Daniela Wenzel 《Angiogenesis》2018,21(2):349-361
Endothelial cell proliferation is a key process during vascular growth but its kinetics could only be assessed in vitro or ex vivo so far. To enable the monitoring and quantification of cell cycle kinetics in vivo, we have generated transgenic mice expressing an eGFP-anillin construct under control of the endothelial-specific Flt-1 promoter. This construct labels the nuclei of endothelial cells in late G1, S and G2 phase and changes its localization during the different stages of M phase, thereby enabling the monitoring of EC proliferation and cytokinesis. In Flt-1/eGFP-anillin mice, we found eGFP+ signals specifically in Ki67+/PECAM+ endothelial cells during vascular development. Quantification using this cell cycle reporter in embryos revealed a decline in endothelial cell proliferation between E9.5 to E12.5. By time-lapse microscopy, we determined the length of different cell cycle phases in embryonic endothelial cells in vivo and found a M phase duration of about 80 min with 2/3 covering karyokinesis and 1/3 cytokinesis. Thus, we have generated a versatile transgenic system for the accurate assessment of endothelial cell cycle dynamics in vitro and in vivo. 相似文献
999.
Breast cancer is the most common malignancy among women and the second leading cause of mortality due to cancer worldwide. The complexity of breast cancer resembles an intricate ecosystem comprising various cleverly designed interaction levels of internal and external factors to generate a pliable context in the clonal evolution of breast cancer cells. Principally, the complex entity can become evident toward delineating a number of significant variations in the specific fields of breast cancer analyses, including the molecular, physiological, and morphological characteristics, clinical presentations, risk factors, the histopathological conditions, and response to systemic therapy regarding the maintenance of tumor as a whole. In hindsight, various classification systems developing based on specific inclusion criteria have indisputably changed both our appreciation of the biological demeanor of breast cancer and the main strategies for designing tailored therapy regimens through the proper evaluation of diagnosis and prognostication of given specimens. Here, we endeavor to provide a general overview of different types of breast cancer classification as well as the clinical acceptance of their applications along with the latest findings in this area. Taken together, the major significance of breast cancer management that can be ascertained by operational convergent points of its stratification areas is owing to the fact that the achievement of individualized and targeted therapy may denounce new horizons of surveillance and treatment strategies in which they may function as a rheostat of specific therapy regimens toward reducing the detected distances between experimental data and operating options in clinical practice. 相似文献
1000.