全文获取类型
收费全文 | 20163篇 |
免费 | 1538篇 |
国内免费 | 1205篇 |
出版年
2024年 | 35篇 |
2023年 | 224篇 |
2022年 | 546篇 |
2021年 | 955篇 |
2020年 | 650篇 |
2019年 | 778篇 |
2018年 | 869篇 |
2017年 | 571篇 |
2016年 | 881篇 |
2015年 | 1217篇 |
2014年 | 1378篇 |
2013年 | 1537篇 |
2012年 | 1858篇 |
2011年 | 1630篇 |
2010年 | 1021篇 |
2009年 | 890篇 |
2008年 | 1117篇 |
2007年 | 976篇 |
2006年 | 864篇 |
2005年 | 774篇 |
2004年 | 616篇 |
2003年 | 577篇 |
2002年 | 488篇 |
2001年 | 361篇 |
2000年 | 298篇 |
1999年 | 295篇 |
1998年 | 182篇 |
1997年 | 141篇 |
1996年 | 109篇 |
1995年 | 113篇 |
1994年 | 82篇 |
1993年 | 71篇 |
1992年 | 98篇 |
1991年 | 98篇 |
1990年 | 87篇 |
1989年 | 68篇 |
1988年 | 56篇 |
1987年 | 53篇 |
1986年 | 39篇 |
1985年 | 45篇 |
1984年 | 25篇 |
1983年 | 23篇 |
1982年 | 21篇 |
1981年 | 14篇 |
1979年 | 20篇 |
1978年 | 16篇 |
1977年 | 19篇 |
1976年 | 15篇 |
1975年 | 14篇 |
1972年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
912.
Yi Feng Jing Liu Longmei Zhai Zengyu Gan Guifen Zhang Shuhua Yang Yi Wang Ting Wu Xinzhong Zhang Xuefeng Xu Zhenhai Han 《Plant, cell & environment》2019,42(2):424-436
Plants experiencing salt‐induced stress often reduce cytokinin levels during the early phases of stress‐response. Interestingly, we found that the cytokinin content in the apple rootstock “robusta” was maintained at a high level under salt stress. Through screening genes involved in cytokinin biosynthesis and catabolism, we found that the high expression levels of IPT5b in robusta roots were involved in maintaining the high cytokinin content. We identified a 42 bp deletion in the promoter region of IPT5b, which elevated IPT5b expression levels, and this deletion was linked to salt tolerance in robusta×M.9 segregating population. The 42 bp deletion resulted in the deletion of a Proline Response Element (ProRE), and our results suggest that ProRE negatively regulates IPT5b expression in response to proline. Under salt stress, the robusta cultivar maintains high cytokinin levels as IPT5b expression cannot be inhibited by proline due to the deletion of ProRE, leading to improve salt tolerance. 相似文献
913.
914.
Han Feng Liu Liping Lu Jiaxi Chai Yingjuan Zhang Jie Wang Shijin Sun Licui Wang Qin Liu Yiqun He Mengjie Mu Weipeng Huang Zhenwu 《Biological trace element research》2019,188(2):363-372
Biological Trace Element Research - The required selenium intake for optimal health in Chinese residents was published in 2014. However, the adequate intake (AI) value for Chinese infants... 相似文献
915.
Zhou Yang Fu Yu Bai Zhendong Li Peixin Zhao Bo Han Yuehua Xu Ting Zhang Ningyan Lin Lin Cheng Jian Zhang Jun Zhang Jing 《Biological trace element research》2019,187(1):172-180
Biological Trace Element Research - The purpose of this study was to evaluate the protective effect of Du-Zhong cortex extract (DZCE) on lead acetate-induced bone loss in rats. Forty female... 相似文献
916.
917.
Zhang Hui Zhang Lu Han Junyou Qian Zhiyuan Zhou Bingying Xu Yunmin Wu Gang 《Plant molecular biology》2019,100(6):571-578
Plant Molecular Biology - A mutation in the nuclear localization signal of squamosa promoter binding like-protein 9 (SPL9) delays vegetative phase change by disrupting its nuclear localization. The... 相似文献
918.
Han Seungsu Lee Yeongmok Park Eun Joo Min Myung Ki Lee Yongsang Kim Tae-Houn Kim Beom-Gi Lee Sangho 《Plant molecular biology》2019,100(3):319-333
Plant Molecular Biology - We determined the structure of OsPYL/RCAR3:OsPP2C50 complex with pyrabactin. Our results suggest that a less-conserved phenylalanine of OsPYL/RCAR subfamily I is... 相似文献
919.
The complete mitogenome of Haliotis iris, an economically important shellfish endemic to New Zealand, was sequenced for the first time. The mitogenome was 17,131?base pairs (bp) in length and contained 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and a control region. All 13 genes were initiated by the start codon ATG, except for nad5 (ATA). Two typical stop codons, TAA and TAG, were present. All of the tRNAs could be folded into typical cloverleaf secondary structures except tRNASer1 and tRNALys, which lacked a DHU stem and complete amino acid acceptor stem, respectively. The control region was 1132?bp in length and contained six AT tandem repeats. According to the gene order of the mitogenome, the 30 analysed Vetigastropoda species could be classified into three types—type I: over half of the studied species were very similar to the gastropod ancestral gene order, and the rearrangements occurred in five tRNAs; type II: eight species were found to be missing several tRNA genes; type III: Fissurellidae, Lepetodrilidae showed a large inverted fragment. 相似文献
920.