全文获取类型
收费全文 | 13357篇 |
免费 | 1197篇 |
国内免费 | 1469篇 |
专业分类
16023篇 |
出版年
2024年 | 41篇 |
2023年 | 191篇 |
2022年 | 411篇 |
2021年 | 625篇 |
2020年 | 509篇 |
2019年 | 586篇 |
2018年 | 532篇 |
2017年 | 422篇 |
2016年 | 575篇 |
2015年 | 887篇 |
2014年 | 1022篇 |
2013年 | 1059篇 |
2012年 | 1365篇 |
2011年 | 1176篇 |
2010年 | 729篇 |
2009年 | 668篇 |
2008年 | 775篇 |
2007年 | 667篇 |
2006年 | 633篇 |
2005年 | 493篇 |
2004年 | 406篇 |
2003年 | 361篇 |
2002年 | 280篇 |
2001年 | 198篇 |
2000年 | 184篇 |
1999年 | 166篇 |
1998年 | 129篇 |
1997年 | 105篇 |
1996年 | 88篇 |
1995年 | 85篇 |
1994年 | 98篇 |
1993年 | 58篇 |
1992年 | 74篇 |
1991年 | 69篇 |
1990年 | 41篇 |
1989年 | 44篇 |
1988年 | 30篇 |
1987年 | 31篇 |
1986年 | 27篇 |
1985年 | 32篇 |
1984年 | 16篇 |
1983年 | 11篇 |
1982年 | 11篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1978年 | 10篇 |
1976年 | 10篇 |
1975年 | 11篇 |
1973年 | 8篇 |
1970年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
Background: Triple-negative breast cancer (TNBC) is a refractory subtype of breast cancer, 25–30% of which have dysregulation in the PI3K/AKT pathway. The present study investigated the anticancer effect of erianin on TNBC cell line and its underlying mechanism.Methods: After treatment with erianin, MTT assay was employed to determine the MDA-MB-231 and EFM-192A cell proliferation, the nucleus morphological changes were observed by DAPI staining. The cell cycle and apoptotic proportion were detected by flow cytometry. Western blot was performed to determine the cell cycle and apoptosis-related protein expression and PI3K pathways. Finally, the antiproliferative activity of erianin was further confirmed by adding or not adding PI3K agonists SC79.Results: Erianin inhibited the proliferation of MDA-MB-231 and EFM-192A cells in a dose-dependent manner, the IC50 were 70.96 and 78.58 nM, respectively. Erianin could cause cell cycle arrest at the G2/M phase, and the expressions of p21 and p27 were up-regulated, while the expressions of CDK1 and Cyclin B1 were down-regulated. Erianin also induced apoptosis via the mitochondrial pathway, with the up-regulation of the expression of Cyto C, PARP, Bax, active form of Caspase-3, and Caspase-9. Furthermore, p-PI3K and p-Akt expression were down-regulated by erianin. After co-incubation with SC79, the cell inhibition rate of erianin was decreased, which further confirmed that the attenuated PI3K/Akt pathway was relevant to the pro-apoptotic effect of erianin.Conclusions: Erianin can inhibit the proliferation of TNBC cells and induce cell cycle arrest and apoptosis, which may ascribe to the abolish the activation of the PI3K/Akt pathway. 相似文献
103.
104.
Zhang Wenwen Xue Fang Xie Shangdan Chen Cheng Li Jingwei Zhu Xueqiong 《Molecular and cellular biochemistry》2021,476(1):45-55
Molecular and Cellular Biochemistry - This study investigated the effect of isoflurane on the proliferation of squamous cervical cancer cells, with focus on histone deacetylase 6 that is closely... 相似文献
105.
Fang Yong E Cailing Wu Shixing Meng Zudong Qin Guifang Wang Rongying 《Cytotechnology》2021,73(6):775-785
Cytotechnology - Psoriasis is a skin disorder that is classed as an autoimmune disease. It is characterized by excessive proliferation, abnormal migration and differentiation of keratinocytes, as... 相似文献
106.
107.
108.
109.
Jinnan Wang Houjun Zhou Yanqiu Zhao Cheng Jiang Jihong Li Fang Tang Yingli Liu Shutang Zhao Jianjun Hu Xueqin Song Meng‐Zhu Lu 《植物学报(英文版)》2021,63(10):1683-1694
110.
Zhijie Ren Fenglin Bai Jingwen Xu Li Wang Xiaohan Wang Qian Zhang Changxin Feng Qi Niu Liying Zhang Jiali Song Fang Bao Liangyu Liu Yikun He Ligeng Ma Wang Tian Congcong Hou Legong Li 《植物学报(英文版)》2021,63(12):2150-2150
Grain size is determined by the size and number of cells in the grain. The regulation of grain size is crucial for improving crop yield; however, the genes and molecular mechanisms that control grain size remain elusive. Here, we report that a member of the detoxification efflux carrier /Multidrug and Toxic Compound Extrusion (DTX/MATE) family transporters, BIG RICE GRAIN 1 (BIRG1), negatively influences grain size in rice (Oryza sativa L.). BIRG1 is highly expressed in reproductive organs and roots. In birg1 grain, the outer parenchyma layer cells of spikelet hulls are larger than in wild-type (WT) grains, but the cell number is unaltered. When expressed in Xenopus laevis oocytes, BIRG1 exhibits chloride efflux activity. Consistent with this role of BIRG1, the birg1 mutant shows reduced tolerance to salt stress at a toxic chloride level. Moreover, grains from birg1 plants contain a higher level of chloride than those of WT plants when grown under normal paddy field conditions, and the roots of birg1 accumulate more chloride than those of WT under saline conditions. Collectively, the data suggest that BIRG1 in rice functions as a chloride efflux transporter that is involved in mediating grain size and salt tolerance by controlling chloride homeostasis. 相似文献