全文获取类型
收费全文 | 21353篇 |
免费 | 1645篇 |
国内免费 | 1517篇 |
出版年
2024年 | 39篇 |
2023年 | 214篇 |
2022年 | 648篇 |
2021年 | 1159篇 |
2020年 | 760篇 |
2019年 | 931篇 |
2018年 | 905篇 |
2017年 | 672篇 |
2016年 | 946篇 |
2015年 | 1293篇 |
2014年 | 1563篇 |
2013年 | 1712篇 |
2012年 | 1887篇 |
2011年 | 1754篇 |
2010年 | 1078篇 |
2009年 | 988篇 |
2008年 | 1129篇 |
2007年 | 1001篇 |
2006年 | 857篇 |
2005年 | 737篇 |
2004年 | 567篇 |
2003年 | 545篇 |
2002年 | 445篇 |
2001年 | 324篇 |
2000年 | 327篇 |
1999年 | 326篇 |
1998年 | 198篇 |
1997年 | 172篇 |
1996年 | 183篇 |
1995年 | 175篇 |
1994年 | 158篇 |
1993年 | 116篇 |
1992年 | 158篇 |
1991年 | 113篇 |
1990年 | 110篇 |
1989年 | 77篇 |
1988年 | 54篇 |
1987年 | 46篇 |
1986年 | 36篇 |
1985年 | 35篇 |
1984年 | 17篇 |
1983年 | 15篇 |
1982年 | 18篇 |
1981年 | 7篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1972年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Yongqiang Yang Ruyue Shao Rong Jiang Min Zhu Li Tang Longjiang Li Li Zhang 《Journal of biochemical and molecular toxicology》2019,33(9)
β‐Hydroxybutyrate (BHB), one of ketone body, has been traditionally regarded as an alternative carrier of energy, but recent studies found that BHB plays versatile roles in inflammation. It has been previously reported that the level BHB declined in mice with lipopolysaccharide (LPS)/d ‐galactosamine (d ‐Gal)‐induced liver damage, but the pathological significance remains unclear. In the present study, the pathophysiological roles of BHB in LPS/d ‐Gal‐induced hepatic damage has been investigated. The results indicated pretreatment with BHB further enhanced LPS/d ‐Gal‐induced elevation of aspartate aminotransferase and alanine aminotransferase, exacerbated the histological abnormalities and increased the mortality. Pretreatment with BHB upregulated the level of tumor necrosis factor α and interleukin‐6 in plasma, promoted the activities of caspase‐3, caspase‐8, and caspase‐9 and increased the count of terminal deoxynucleotidyl transferase dUTP nick end labeling‐positive cells. In addition, post‐insult supplement with BHB also potentiated LPS/d ‐Gal‐induced apoptotic liver damage. Therefore, BHB might be a detrimental factor in LPS/d ‐Gal‐induced liver injury via enhancing the inflammation and the apoptosis in the liver. 相似文献
972.
973.
Ai‐Hua Tong Juan Tan Jin‐Hua Zhang Fang‐Jiang Xu Fu‐Yuan Li Chun‐Yu Cao 《Journal of biochemical and molecular toxicology》2019,33(2)
Ring1 and YY1 binding protein (RYBP), a new member of the polycomb group protein family, has been reported to play an important role in various biological processes. Recently, more and more studies have demonstrated an implication of RYBP in cancer development. However, the specific role of RYBP in anaplastic thyroid cancer (ATC) remains unknown. In this study, we investigated for the first time the expression pattern and biological functions of RYBP in ATC. We showed that RYBP was lowly expressed in ATC tissues and cell lines. We also found that overexpression of RYBP inhibited ATC cell proliferation, invasion, and cisplatin resistance. Furthermore, we observed that upregulation of RYBP decreased the phosphorylation of EGFR and ERK1/2 in ATC cells. Taken together, our data indicated that RYBP might be considered as a promising therapeutic target for the treatment of ATC. 相似文献
974.
Zhang Zhe Fan Junxia Long Chuannan He Bin Hu Zhihong Jiang Chunmiao Li Yongkai Ma Long Wen Jingshang Zou Xiaojin Chen Yuan Ge Zhenxiang Zeng Bin 《Journal of industrial microbiology & biotechnology》2019,46(12):1769-1780
Journal of Industrial Microbiology & Biotechnology - The ZRT, IRT-like protein (ZIP) family exists in many species and plays an important role in many biological processes, but little is known... 相似文献
975.
Zhu Linjiang Jiang Dan Zhou Yaoyao Lu Yuele Fan Yongxian Chen Xiaolong 《Journal of industrial microbiology & biotechnology》2019,46(6):759-767
Journal of Industrial Microbiology & Biotechnology - α-Arbutin is an effective skin-whitening cosmetic ingredient and can be synthesized through hydroquinone glycosylation. In this study,... 相似文献
976.
Yijuan Shen Nini Zhou Jiahui An Jiansong Zhang Meifen Wang Yufeng Li Ping Jiang 《Cellular microbiology》2019,21(8)
Haemophilus parasuis (H. parasuis) is a common commensal in the upper respiratory tract of pigs, but causes Glässer's disease in stress conditions. To date, many studies focused on the immune evasion and virulence of H. parasuis; very few have focused on the role autophagy played in H. parasuis infection, particularly in porcine alveolar macrophages (PAMs). In this study, a PAM cell line, 3D4/21 cells were used to study the role of autophagy in H. parasuis infection. 3D4/21 cells tandemly expressing GFP, mCherry, and LC3 were infected with H. parasuis serovar 5 (Hps5). Western blot analysis and confocal and transmission electron microscopy showed that H. parasuis infection effectively induces autophagy. Using Hps strains of varying virulence (Hps4, Hps5, and Hps7) and UV‐inactivated Hps5, we demonstrated that autophagy is associated with the internalisation of living virulent strains into cells. In 3D4/21 cells pretreated with rapamycin and 3‐MA then infected by Hps4, Hps5, and Hps7, we demonstrated that autophagy affects invasion of H. parasuis in cells. AMPK signal results showed that Hps5 infection can upregulate the phosphorylation level of AMPK, which is consistent with the autophagy development. 3D4/21 cells pretreated with AICAR or Compound C then infected by Hps5 revealed that the autophagy induced by Hps5 infection is associated with the AMPK pathway. Our study contributes to the theoretical basis for the study of H. parasuis pathogenesis and development of novel drugs target for prevention Glässer's disease. 相似文献
977.
Ying Wen Shouwen Chen Zhiwei Jiang Zhuang Wang Jinchao Tan Tianjian Hu Qiyao Wang Xiangshan Zhou Yuanxing Zhang Qin Liu Dahai Yang 《Cellular microbiology》2019,21(6)
Inflammasomes are important innate immune components in mammals. However, the bacterial factors modulating inflammasome activation in fish, and the mechanisms by which they alter fish immune defences, remain to be investigated. In this work, a mutant of the fish pathogen Edwardsiella piscicida (E. piscicida), called 0909I, was shown to overexpress haemolysin, which could induce a robust pyroptotic‐like cell death dependent on caspase‐5‐like activity during infection in fish nonphagocyte cells. E. piscicida haemolysin was found to mainly associate with bacterial outer membrane vesicles (OMVs), which were internalised into the fish cells via a dynamin‐dependent endocytosis and induced pyroptotic‐like cell death. Importantly, bacterial immersion infection of both larvae and adult zebrafish suggested that dysregulated expression of haemolysin alerts the innate immune system and induces intestinal inflammation to restrict bacterial colonisation in vivo. Taken together, these results suggest a critical role of zebrafish innate immunity in monitoring invaded pathogens via detecting the bacterial haemolysin‐associated OMVs and initiating pyroptotic‐like cell death. These new additions to the understanding of haemolysin‐mediated pathogenesis in vivo provide evidence for the existence of noncanonical inflammasome signalling in lower vertebrates. 相似文献
978.
979.
980.
为了探明海草床内主要生物类群间的营养关系以及食物网结构, 作者于2018年8月分别在东营黄河口潮间带和烟台西海岸潮间带海草床采集大型底栖生物样品, 采用δ 13C和δ 15N稳定同位素方法, 对生物样品的碳、氮同位素组成进行了测定和分析。结果表明: 东营海草床内生物的δ 13C、δ 15N值范围分别为-21.99‰至-12.13‰和5.23‰-11.05‰, 烟台海草床内生物的δ 13C、δ 15N值范围分别为-18.11‰至-14.06‰和6.60‰-10.22‰。东营海草床主要生物的营养级范围为2.00-3.85, 烟台海草床主要生物的营养级范围为2.00-3.15。根据δ 15N值计算所得的营养级图分析可知两区域海草床内初级消费者主要为滤食性双壳类和多毛类, 次级消费者为植食性或杂食性甲壳类,肉食性鱼类和腹足类。与近海海域大型底栖生物食物网相比, 海草床内底栖生物的营养级均值普遍较低。 相似文献