全文获取类型
收费全文 | 6189篇 |
免费 | 405篇 |
国内免费 | 431篇 |
专业分类
7025篇 |
出版年
2024年 | 12篇 |
2023年 | 67篇 |
2022年 | 187篇 |
2021年 | 311篇 |
2020年 | 193篇 |
2019年 | 252篇 |
2018年 | 232篇 |
2017年 | 188篇 |
2016年 | 254篇 |
2015年 | 384篇 |
2014年 | 445篇 |
2013年 | 471篇 |
2012年 | 543篇 |
2011年 | 518篇 |
2010年 | 341篇 |
2009年 | 279篇 |
2008年 | 331篇 |
2007年 | 289篇 |
2006年 | 259篇 |
2005年 | 227篇 |
2004年 | 191篇 |
2003年 | 149篇 |
2002年 | 131篇 |
2001年 | 98篇 |
2000年 | 80篇 |
1999年 | 88篇 |
1998年 | 43篇 |
1997年 | 58篇 |
1996年 | 58篇 |
1995年 | 45篇 |
1994年 | 33篇 |
1993年 | 35篇 |
1992年 | 48篇 |
1991年 | 42篇 |
1990年 | 28篇 |
1989年 | 21篇 |
1988年 | 12篇 |
1987年 | 25篇 |
1986年 | 16篇 |
1985年 | 15篇 |
1984年 | 1篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有7025条查询结果,搜索用时 15 毫秒
151.
152.
Shen He Wu Shuyu Chen Xi Xu Bai Ma Dezun Zhao Yannan Zhuang Yan Chen Bing Hou Xianglin Li Jiayin Cao Yudong Fu Xianyong Tan Jun Yin Wen Li Juan Meng Li Shi Ya Xiao Zhifeng Jiang Xingjun Dai Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we... 相似文献
153.
To establish infection, plant viruses are evolutionarily empowered with the ability to spread intercellularly. Potyviruses represent the largest group of known plant-infecting RNA viruses, including many agriculturally important viruses. To better understand intercellular movement of potyviruses, we used turnip mosaic virus (TuMV) as a model and constructed a double-fluorescent (green and mCherry) protein-tagged TuMV infectious clone, which allows distinct observation of primary and secondary infected cells. We conducted a series of deletion and mutation analyses to characterize the role of TuMV coat protein (CP) in viral intercellular movement. TuMV CP has 288 amino acids and is composed of three domains: the N-terminus (amino acids 1–97), the core (amino acids 98–245), and the C-terminus (amino acids 246–288). We found that deletion of CP or its segments amino acids 51–199, amino acids 200–283, or amino acids 265–274 abolished the ability of TuMV to spread intercellularly but did not affect virus replication. Interestingly, deletion of amino acids 6–50 in the N-terminus domain resulted in the formation of aberrant virions but did not significantly compromise TuMV cell-to-cell and systemic movement. We identified the charged residues R178 and D222 within the core domain that are essential for virion formation and TuMV local and systemic transport in plants. Moreover, we found that trans-expression of the wild-type CP either by TuMV or through genetic transformation-based stable expression could not rescue the movement defect of CP mutants. Taken together these results suggest that TuMV CP is not essential for viral genome replication but is indispensable for viral intercellular transport where only the cis-expressed CP is functional. 相似文献
154.
Dan Wang Li Tian Dan-Dan Zhang Jian Song Shuang-Shuang Song Chun-Mei Yin Lei Zhou Yan Liu Bao-Li Wang Zhi-Qiang Kong Steven J. Klosterman Jun-Jiao Li Jie Wang Ting-Gang Li Sabiu Adamu Krishna V. Subbarao Jie-Yin Chen Xiao-Feng Dai 《Molecular Plant Pathology》2020,21(5):667-685
Secreted small cysteine-rich proteins (SCPs) play a critical role in modulating host immunity in plant–pathogen interactions. Bioinformatic analyses showed that the fungal pathogen Verticillium dahliae encodes more than 100 VdSCPs, but their roles in host–pathogen interactions have not been fully characterized. Transient expression of 123 VdSCP-encoding genes in Nicotiana benthamiana identified three candidate genes involved in host–pathogen interactions. The expression of these three proteins, VdSCP27, VdSCP113, and VdSCP126, in N. benthamiana resulted in cell death accompanied by a reactive oxygen species burst, callose deposition, and induction of defence genes. The three VdSCPs mainly localized to the periphery of the cell. BAK1 and SOBIR1 (associated with receptor-like protein) were required for the immunity triggered by these three VdSCPs in N. benthamiana. Site-directed mutagenesis showed that cysteine residues that form disulphide bonds are essential for the functioning of VdSCP126, but not VdSCP27 and VdSCP113. VdSCP27, VdSCP113, and VdSCP126 individually are not essential for V. dahliae infection of N. benthamiana and Gossypium hirsutum, although there was a significant reduction of virulence on N. benthamiana and G. hirsutum when inoculated with the VdSCP27/VdSCP126 double deletion strain. These results illustrate that the SCPs play a critical role in the V. dahliae–plant interaction via an intrinsic virulence function and suppress immunity following infection. 相似文献
155.
156.
157.
158.
Wei Chen Daofeng Zheng Tong Mou Junliang Pu Jiangwen Dai Zuotian Huang 《Bioscience, biotechnology, and biochemistry》2020,84(6):1176-1182
ABSTRACTLiver damage induced by ischemia/reperfusion (I/R) remains a primary issue in multiple hepatic surgeries. Innate immune-mediated inflammatory responses during the reperfusion stage aggravate the injury. Nevertheless, the detailed mechanism of hepatic I/R has not been fully clarified yet. Our research focuses on the role of Transducin-like enhancer of split-1 (Tle1) in the liver I/R injury and the relation between Tle1 and Nucleotide-binding oligomerization domain 2 (NOD2). To answer these questions, we constructed mouse models of I/R and cell models of hypoxia/reoxygenation (H/R). We found decreased Tle1 accompanied by increased NOD2 during reperfusion. Mice pro-injected with Tle1-siRNA emerged aggravated liver dysfunction. Repression of Tle1 had a significant impact on NOD2 and downstream NF-κB signaling in vitro. However, alteration of NOD2 failed to affect the expression of Tle1. To conclude, our study demonstrates that Tle1 shelters the liver from I/R injury through suppression of NOD2-dependent NF-κB activation and subsequent inflammatory responses. 相似文献
159.
Pan-Pan Lu Min-Hao Chen Guang-Chun Dai Ying-Juan Li Liu Shi Yun-Feng Rui 《World journal of stem cells》2020,12(11):1255-1275
There is accumulating evidence of an increased incidence of tendon disorders in people with diabetes mellitus. Diabetic tendinopathy is an important cause of chronic pain, restricted activity, and even tendon rupture in individuals. Tenocytes and tendon stem/progenitor cells (TSPCs) are the dominant cellular components associated with tendon homeostasis, maintenance, remodeling, and repair. Some previous studies have shown alterations in tenocytes and TSPCs in high glucose or diabetic conditions that might cause structural and functional variations in diabetic tendons and even accelerate the development and progression of diabetic tendinopathy. In this review, the biomechanical properties and histopathological changes in diabetic tendons are described. Then, the cellular and molecular alterations in both tenocytes and TSPCs are summarized, and the underlying mechanisms involved are also analyzed. A better understanding of the underlying cellular and molecular pathogenesis of diabetic tendinopathy would provide new insight for the exploration and development of effective therapeutics. 相似文献
160.
Xue-Jun Cheng Fu-Lai Guan Qian Li Gong Dai Hai-Feng Li Xue-Kun Li 《World journal of stem cells》2020,12(11):1354-1365
BACKGROUNDAs the third most abundant element, aluminum is widespread in the environment. Previous studies have shown that aluminum has a neurotoxic effect and its exposure can impair neuronal development and cognitive function.AIMTo study the effects of aluminum on epigenetic modification in neural stem cells and neurons. METHODSNeural stem cells were isolated from the forebrain of adult mice. Neurons were isolated from the hippocampi tissues of embryonic day 16-18 mice. AlCl3 at 100 and 200 μmol/L was applied to stem cells and neurons. RESULTSAluminum altered the differentiation of adult neural stem cells and caused apoptosis of newborn neurons while having no significant effects on the proliferation of neural stem cells. Aluminum application also significantly inhibited the dendritic development of hippocampal neurons. Mechanistically, aluminum exposure significantly affected the levels of DNA 5-hydroxy-methylcytosine, 5-methylcytosine, and N6-methyladenine in stem cells and neurons. CONCLUSIONOur findings indicate that aluminum may regulate neuronal development by modulating DNA modifications. 相似文献