全文获取类型
收费全文 | 3233篇 |
免费 | 202篇 |
国内免费 | 302篇 |
出版年
2024年 | 9篇 |
2023年 | 59篇 |
2022年 | 153篇 |
2021年 | 248篇 |
2020年 | 161篇 |
2019年 | 159篇 |
2018年 | 159篇 |
2017年 | 115篇 |
2016年 | 170篇 |
2015年 | 219篇 |
2014年 | 253篇 |
2013年 | 279篇 |
2012年 | 323篇 |
2011年 | 270篇 |
2010年 | 136篇 |
2009年 | 119篇 |
2008年 | 137篇 |
2007年 | 131篇 |
2006年 | 112篇 |
2005年 | 90篇 |
2004年 | 48篇 |
2003年 | 55篇 |
2002年 | 47篇 |
2001年 | 21篇 |
2000年 | 32篇 |
1999年 | 32篇 |
1998年 | 24篇 |
1997年 | 18篇 |
1996年 | 14篇 |
1995年 | 18篇 |
1994年 | 10篇 |
1993年 | 13篇 |
1992年 | 19篇 |
1991年 | 16篇 |
1990年 | 9篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1974年 | 2篇 |
1971年 | 1篇 |
1966年 | 2篇 |
排序方式: 共有3737条查询结果,搜索用时 31 毫秒
61.
为拓宽小麦矮秆遗传资源,利用γ射线辐照济麦22获得了一个赤霉素不敏感型矮秆突变体jm22d。株高相关性状调查结果及茎秆细胞学试验显示,jm22d株高为53±1.8 cm,比野生型(WT)低约20 cm。jm22d整株茎秆共有4节,比WT少一节且各节间长度显著小于WT。与WT相比,jm22d茎秆细胞长度缩短。赤霉素含量测定发现,jm22d叶片中赤霉素含量高于WT,而茎秆中赤霉素含量低于WT(P<0.01),因此,jm22d株高降低与赤霉素转运途径出现异常有关。为了深入研究jm22d对赤霉素的响应机理,对jm22d和WT幼苗进行赤霉素处理,分别收取处理0(D0)、1(D1)和3 d(D3)的样品进行转录组学分析。结果表明,与WT相比,在jm22d中共筛选到696个上调和1 067个下调的表达基因,其中62个和349个基因在3个时间点分别表现为上调和下调表达。叶绿素含量测定表明,jm22d中叶绿素含量随赤霉素处理时间的延长而降低,聚类分析结果表明,差异表达基因主要富集在光合作用-天线蛋白(photosynthesis-antenna proteins,ko00196)、卟啉和叶绿素代谢(porphyrin and chlorophyll metabolism,ko00860)、亚油酸新陈代谢(linoleic acid metabolism,ko00591)等通路,因此赤霉素处理对jm22d体内叶绿素含量的积累具有抑制作用。通过KEGG分析在植物激素信号转导途径中挖掘到5个差异表达基因(TraesCS2B01G582300、TraesCS2B01G600800、TraesCS2B01G556600、TraesCS2B01G630000和TraesCS6B01G439600)参与生长素、细胞分裂素等激素代谢途径,这些基因在jm22d中显著下调,这可能是jm22d矮化的重要原因。研究结果为矮秆突变体矮化机制的解析提供了重要参考。 相似文献
62.
Photosynthesis Research - Formation of photosynthetic complexes leads to a higher demand for Fe–S clusters. We hypothesized that in the facultative phototrophic alpha-proteobacterium... 相似文献
63.
Chen Minmin Nie Gongping Yang Liuyan Zhang Yongchun Cai Youming 《Plant Growth Regulation》2021,95(1):49-64
Plant Growth Regulation - As one of the most popular bulbous plant with high ornamental value, Lilium spp. has been used as cut flower or green plants in urban landscapes and home gardening. We... 相似文献
64.
65.
Yan Yan Zhao Sihan Ding Zehong Tie Weiwei Hu Wei 《Plant Molecular Biology Reporter》2021,39(3):607-616
Plant Molecular Biology Reporter - Cassava is an important starchy and food crop; however, the commercial value of cassava is seriously constrained by postharvest physiological deterioration (PPD).... 相似文献
66.
Wei Tong Ruopei Li Jin Huang Huijuan Zhao Ruoheng Ge Qiong Wu Ali I. Mallano Yanli Wang Fangdong Li Weiwei Deng Yeyun Li Enhua Xia 《The Plant journal : for cell and molecular biology》2021,106(5):1312-1327
The tea plant (Camellia sinensis) is a thermophilic cash crop and contains a highly duplicated and repeat-rich genome. It is still unclear how DNA methylation regulates the evolution of duplicated genes and chilling stress in tea plants. We therefore generated a single-base-resolution DNA methylation map of tea plants under chilling stress. We found that, compared with other plants, the tea plant genome is highly methylated in all three sequence contexts, including CG, CHG and CHH (where H = A, T, or C), which is further proven to be correlated with its repeat content and genome size. We show that DNA methylation in the gene body negatively regulates the gene expression of tea plants, whereas non-CG methylation in the flanking region enables a positive regulation of gene expression. We demonstrate that transposable element-mediated methylation dynamics significantly drives the expression divergence of duplicated genes in tea plants. The DNA methylation and expression divergence of duplicated genes in the tea plant increases with evolutionary age and selective pressure. Moreover, we detect thousands of differentially methylated genes, some of which are functionally associated with chilling stress. We also experimentally reveal that DNA methyltransferase genes of tea plants are significantly downregulated, whereas demethylase genes are upregulated at the initial stage of chilling stress, which is in line with the significant loss of DNA methylation of three well-known cold-responsive genes at their promoter and gene body regions. Overall, our findings underscore the importance of DNA methylation regulation and offer new insights into duplicated gene evolution and chilling tolerance in tea plants. 相似文献
67.
Zhu Lin Ping Weiwei Zhang Siyue Chen Ya Zhang Ying Zhang Jianli 《Antonie van Leeuwenhoek》2021,114(12):2219-2228
Antonie van Leeuwenhoek - A novel pink-pigmented bacterium, designated strain 3D7T, was isolated during an investigation of potential psychrotolerant species from Antarctic soil. Cells of the... 相似文献
68.
69.
Sheng Chen Xinheng Zhang Yu Nie Hongxin Li Weiguo Chen Wencheng Lin Feng Chen Qingmei Xie 《中国病毒学》2021,36(2):196-206
African swine fever virus(ASFV), as a member of the large DNA viruses, may regulate autophagy and apoptosis by inhibiting programmed cell death. However, the function of ASFV proteins has not been fully elucidated, especially the role of autophagy in ASFV infection. One of three Pyrroline-5-carboxylate reductases(PYCR), is primarily involved in conversion of glutamate to proline. Previous studies have shown that depletion of PYCR2 was related to the induction of autophagy. In the present study, we found for the first time that ASFV E199 L protein induced a complete autophagy process in Vero and HEK-293 T cells. Through co-immunoprecipitation coupled with mass spectrometry(CoIP-MS)analysis, we firstly identified that E199 L interact with PYCR2 in vitro. Importantly, our work provides evidence that E199 L down-regulated the expression of PYCR2, resulting in autophagy activation. Overall, our results demonstrate that ASFV E199 L protein induces complete autophagy through interaction with PYCR2 and down-regulate the expression level of PYCR2, which provide a valuable reference for the role of autophagy during ASFV infection and contribute to the functional clues of PYCR2. 相似文献
70.
Zhang Xinheng Chen Tong Chen Sheng Nie Yu Xie Zi Feng Keyu Zhang Huanmin Xie Qingmei 《中国病毒学》2021,36(6):1431-1442
Virologica Sinica - Infectious bronchitis (IB) is a highly contagious avian disease caused by infection with infectious bronchitis virus (IBV), which seriously affects the development of the global... 相似文献