全文获取类型
收费全文 | 25075篇 |
免费 | 2024篇 |
国内免费 | 843篇 |
专业分类
27942篇 |
出版年
2024年 | 41篇 |
2023年 | 242篇 |
2022年 | 622篇 |
2021年 | 944篇 |
2020年 | 593篇 |
2019年 | 753篇 |
2018年 | 779篇 |
2017年 | 612篇 |
2016年 | 865篇 |
2015年 | 1383篇 |
2014年 | 1489篇 |
2013年 | 1737篇 |
2012年 | 2099篇 |
2011年 | 1911篇 |
2010年 | 1227篇 |
2009年 | 1109篇 |
2008年 | 1362篇 |
2007年 | 1246篇 |
2006年 | 1085篇 |
2005年 | 976篇 |
2004年 | 885篇 |
2003年 | 748篇 |
2002年 | 675篇 |
2001年 | 496篇 |
2000年 | 434篇 |
1999年 | 373篇 |
1998年 | 233篇 |
1997年 | 221篇 |
1996年 | 208篇 |
1995年 | 195篇 |
1994年 | 155篇 |
1993年 | 136篇 |
1992年 | 221篇 |
1991年 | 178篇 |
1990年 | 162篇 |
1989年 | 163篇 |
1988年 | 143篇 |
1987年 | 149篇 |
1986年 | 128篇 |
1985年 | 127篇 |
1984年 | 102篇 |
1983年 | 86篇 |
1982年 | 59篇 |
1980年 | 45篇 |
1979年 | 66篇 |
1978年 | 50篇 |
1977年 | 43篇 |
1976年 | 53篇 |
1975年 | 43篇 |
1974年 | 39篇 |
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
91.
92.
93.
94.
Cheon H Rho YH Choi SJ Lee YH Song GG Sohn J Won NH Ji JD 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(2):1092-1100
In inflamed joints of rheumatoid arthritis, PGE(2) is highly expressed, and IL-10 and IL-6 are also abundant. PGE(2) is a well-known activator of the cAMP signaling pathway, and there is functional cross-talk between cAMP signaling and the Jak-STAT signaling pathway. In this study, we evaluated the modulating effect of PGE(2) on STAT signaling and its biological function induced by IL-10 and IL-6, and elucidated its mechanism in THP-1 cells. STAT phosphorylation was determined by Western blot, and gene expression was analyzed using real-time PCR. Pretreatment with PGE(2) significantly augmented IL-10-induced STAT3 and STAT1 phosphorylation, as well as suppressors of cytokine signaling 3 (SOCS3) and IL-1R antagonist gene expression. In contrast, PGE(2) suppressed IL-6-induced phosphorylation of STAT3 and STAT1. These PGE(2)-induced modulating effects were largely reversed by actinomycin D. Pretreatment with dibutyryl cAMP augmented IL-10-induced, but did not change IL-6-induced STAT3 phosphorylation. Misoprostol, an EP2/3/4 agonist, and butaprost, an EP2 agonist, augmented IL-10-induced STAT3 phosphorylation and SOCS3 gene expression, but sulprostone, an EP1/3 agonist, had no effect. H89, a protein kinase A inhibitor, and LY294002, a PI3K inhibitor, diminished PGE(2)-mediated augmentation of IL-10-induced STAT3 phosphorylation. In this study, we found that PGE(2) selectively regulates cytokine signaling via increased intracellular cAMP levels and de novo gene expression, and these modulating effects may be mediated through EP2 or EP4 receptors. PGE(2) may modulate immune responses by alteration of cytokine signaling in THP-1 cells. 相似文献
95.
96.
97.
98.
Chiakang Ho Ya Gao Danning Zheng Yanjun Liu Shengzhou Shan Bin Fang Yixuan Zhao Dingzhong Song Yifan Zhang Qingfeng Li 《Journal of cellular and molecular medicine》2019,23(8):5108-5118
Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases. 相似文献
99.
Ho Cheng Koc Jing Xiao Weiwei Liu Yong Li Guokai Chen 《International journal of biological sciences》2022,18(12):4768
The pandemic of COVID-19 is the biggest public health crisis in 21st Century. Besides the acute symptoms after infection, patients and society are also being challenged by the long-term health complications associated with COVID-19, commonly known as long COVID. While health professionals work hard to find proper treatments, large amount of knowledge has been accumulated in recent years. In order to deal with long COVID efficiently, it is important for people to keep up with current progresses and take proactive actions on long COVID. For this purpose, this review will first introduce the general background of long COVID, and then discuss its risk factors, diagnostic indicators and management strategies. This review will serve as a useful resource for people to understand and prepare for long COVID that will be with us in the foreseeable future. 相似文献
100.
Zhugang Li Lingxia Zhao Guoyin Kai Shunwu Yu Youfang Cao Yongzhen Pang Xiaofen Sun Kexuan Tang 《Plant Physiology and Biochemistry》2004,42(10):789-794
Plant growth and productivity are greatly affected by water stress, such as drought and salinity. Here we report on the cloning and expression analysis of a water stress-induced gene from Brassica oleracea (designated as BoWS, GenBank accession number AY571333) by rapid amplification of cDNA ends (RACE). The full-length cDNA of BoWS consisted of 594 bp and contained a 285 bp open reading frame (ORF) encoding a 95-amino-acid protein. The deduced protein had a calculated molecular mass of 10.53 kDa and an isoelectric point of 6.93. The sequence similarity and comparative analysis showed that BoWS was 84% identical to Arabidopsis thaliana putative water stress-induced protein (GenBank accession number AAM67282). Southern blot analysis indicated that BoWS was a low-copy gene. Northern blot analysis revealed that the expression of BoWS was upregulated by abscisic acid (ABA), mannitol, NaCl, drought, salicylic acid (SA) and hydrogen peroxide (H(2)O(2)). Our results indicate that BoWS is extremely related to the water-deficit stress in B. oleracea. 相似文献