全文获取类型
收费全文 | 75634篇 |
免费 | 5460篇 |
国内免费 | 1676篇 |
出版年
2024年 | 73篇 |
2023年 | 458篇 |
2022年 | 1212篇 |
2021年 | 2296篇 |
2020年 | 1509篇 |
2019年 | 1878篇 |
2018年 | 2155篇 |
2017年 | 1710篇 |
2016年 | 2650篇 |
2015年 | 4157篇 |
2014年 | 4729篇 |
2013年 | 5154篇 |
2012年 | 6464篇 |
2011年 | 5985篇 |
2010年 | 3771篇 |
2009年 | 3366篇 |
2008年 | 4430篇 |
2007年 | 4177篇 |
2006年 | 3620篇 |
2005年 | 3267篇 |
2004年 | 2928篇 |
2003年 | 2543篇 |
2002年 | 2149篇 |
2001年 | 1835篇 |
2000年 | 1648篇 |
1999年 | 1429篇 |
1998年 | 648篇 |
1997年 | 607篇 |
1996年 | 512篇 |
1995年 | 431篇 |
1994年 | 435篇 |
1993年 | 334篇 |
1992年 | 561篇 |
1991年 | 493篇 |
1990年 | 419篇 |
1989年 | 350篇 |
1988年 | 271篇 |
1987年 | 281篇 |
1986年 | 227篇 |
1985年 | 185篇 |
1984年 | 145篇 |
1983年 | 133篇 |
1982年 | 102篇 |
1981年 | 88篇 |
1980年 | 81篇 |
1979年 | 104篇 |
1978年 | 76篇 |
1977年 | 77篇 |
1975年 | 77篇 |
1974年 | 89篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Ke Wang Feiyun Xu Wei Yuan Dongping Zhang Jianping Liu Leyun Sun Liyou Cui Jianhua Zhang Weifeng Xu 《The Plant journal : for cell and molecular biology》2021,107(6):1603-1615
Heterotrimeric G protein is involved in plant growth and development, while the role of rice (Oryza sativa) G protein γ subunit qPE9-1 in response to low-phosphorus (LP) conditions remains unclear. The gene expression of qPE9-1 was significantly induced in rice roots under LP conditions. Rice varieties carrying the qPE9-1 allele showed a stronger primary root response to LP than the varieties carrying the qpe9-1 allele (mutant of the qPE9-1 allele). Transgenic rice plants with the qPE9-1 allele had longer primary roots and higher P concentrations than those with the qpe9-1 allele under LP conditions. The plasma membrane (PM) H+-ATPase was important for the qPE9-1-mediated response to LP. Furthermore, OsGF14b, a 14-3-3 protein that acts as a key component in activating PM H+-ATPase for root elongation, is also involved in the qPE9-1 mediation. Moreover, the overexpression of OsGF14b in WYJ8 (carrying the qpe9-1 allele) partially increased primary root length under LP conditions. Experiments using R18 peptide (a 14-3-3 protein inhibitor) showed that qPE9-1 is important for primary root elongation and H+ efflux under LP conditions by involving the 14-3-3 protein. In addition, rhizosheath weight, total P content, and the rhizosheath soil Olsen-P concentration of qPE9-1 lines were higher than those of qpe9-1 lines under soil drying and LP conditions. These results suggest that the G protein γ subunit qPE9-1 in rice plants modulates root elongation for phosphorus uptake by involving the 14-3-3 protein OsGF14b and PM H+-ATPase, which is required for rice P use. 相似文献
83.
84.
The purpose of this review is to provide an overview of the effects of adenovirus and influenza virus infections on obesity in various experimental models. We reviewed studies that were conducted within the past 10 years and were related to virus infection and obesity prevalence. Here, we discuss a different causal relationship between adenovirus and influenza infections with obesity. Adenovirus infection can cause obesity, whereas obesity can be a risk factor for increasing influenza virus infection and increases the risk of morbidity and mortality. The prevalence of obesity due to adenovirus infections may be due to an increase in glucose uptake and reduction in lipolysis caused by an increase in corticosterone secretion. Adenovirus infections may lead to increases in appetite by decreasing norepinephrine and leptin levels and also cause immune dysfunction. The relationship between obesity and influenza virus infection could be summarized by the following features: decreases in memory T-cell functionality and interferon (IFN)-α, IFN-β, and IFN-γ mRNA expression, increases in viral titer and infiltration, and impaired dendritic cell function in obese individuals. Moreover, leptin resistance may play an important role in increasing influenza virus infections in obese individuals. In conclusion, prevention of adenovirus infections could be a good approach for reducing obesity prevalence, and prevention of obesity could reduce influenza virus infections from the point of view of viral infections and obesity. 相似文献
85.
86.
87.
Yoko Yamauchi Hikari Kimoto Xianyu Yang Sergey Filkin Yuri Utkin Tai Kubo 《Bioscience, biotechnology, and biochemistry》2016,80(1):158-161
Three-finger toxins (3FTxs) are one of the major components in snake venoms. In this study, we isolated a cDNA encoding a short-chain 3FTx, Pr-SNTX, from Pseudechis rossignolii. The amino acid sequence of Pr-SNTX is nearly identical to that of its ortholog in Pseudechis australis. Pr-SNTX protein inhibited muscle-type (α2βδε), but not neuronal α7 nicotinic acetylcholine receptor (nAChR) activity. 相似文献
88.
J Chae M J Kim J H Goo S Collier D Gubb J Charlton P N Adler W J Park 《Development (Cambridge, England)》1999,126(23):5421-5429
The tissue polarity genes control the polarity of hairs, bristles and ommatidia in the adult epidermis of Drosophila. We report here the identification of a new tissue polarity gene named starry night (stan). Mutations in this essential gene alter the polarity of cuticular structures in all regions of the adult body. The detailed polarity phenotype of stan on the wing suggested that it is most likely a component of the frizzled (fz) pathway. Consistent with this hypothesis, stan appears to be downstream of and required for fz function. We molecularly cloned stan and found that it encodes a huge protocadherin containing nine cadherin motifs, four EGF-like motifs, two laminin G motifs, and seven transmembrane domains. This suggests that Stan functions in signal reception, perhaps together with Fz. 相似文献
89.
90.