全文获取类型
收费全文 | 1288篇 |
免费 | 108篇 |
国内免费 | 1篇 |
出版年
2023年 | 8篇 |
2022年 | 18篇 |
2021年 | 41篇 |
2020年 | 10篇 |
2019年 | 26篇 |
2018年 | 24篇 |
2017年 | 12篇 |
2016年 | 34篇 |
2015年 | 77篇 |
2014年 | 80篇 |
2013年 | 74篇 |
2012年 | 121篇 |
2011年 | 113篇 |
2010年 | 54篇 |
2009年 | 39篇 |
2008年 | 82篇 |
2007年 | 79篇 |
2006年 | 65篇 |
2005年 | 67篇 |
2004年 | 51篇 |
2003年 | 53篇 |
2002年 | 60篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 14篇 |
1998年 | 11篇 |
1997年 | 8篇 |
1996年 | 8篇 |
1995年 | 7篇 |
1993年 | 5篇 |
1992年 | 11篇 |
1991年 | 10篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 9篇 |
1982年 | 8篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1976年 | 5篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1970年 | 6篇 |
1969年 | 3篇 |
1967年 | 4篇 |
1945年 | 2篇 |
1929年 | 3篇 |
排序方式: 共有1397条查询结果,搜索用时 203 毫秒
111.
Martins Renato T. Brito Janaina Dias-Silva Karina Leal Ceclia G. Leito Rafael P. Oliveira Vivian C. Oliveira-Jnior Jos M. B. de Paula Felipe R. Roque Fabio O. Hamada Neusa Juen Leandro Nessimian Jorge L. Pompeu Paulo S. Hughes Robert M. 《Hydrobiologia》2022,849(10):2281-2298
Hydrobiologia - Stream degradation in Amazonia is outpacing our ability to effectively monitor it for three key reasons: (1) Many changes are cumulative and occur gradually; (2) Scientists have... 相似文献
112.
113.
114.
115.
116.
117.
α‐ l‐iduronidase gene‐based therapy using the phiC31 system to treat mucopolysaccharidose type I mice 下载免费PDF全文
Roberta Sessa Stilhano Priscila Keiko Matsumoto Martin Suely Maymone de Melo Vivian Yochiko Samoto Giovani Bravin Peres Yara Maria Correa da Silva Michelacci Flavia Helena da Silva Vanessa Gonçalves Pereira Vania D'Almeida Adriana Taveira da Cruz Miriam Galvonas Jasiulionis Sang Won Han 《The journal of gene medicine》2015,17(1-2):1-13
118.
Vivian Flinte Ethel Hentz Barbara Mascarenhas Morgado Anne Caruliny do Monte Lima Gabriel Khattar Ricardo Ferreira Monteiro Margarete Valverde de Macedo 《ZooKeys》2015,(547):119-132
The population phenology of the cassidines, Coptocycla
arcuata and Omaspides
trichroa, and the chrysomeline, Platyphora
axillaris, was studied at Serra dos Órgãos National Park, State of Rio de Janeiro, southeast Brazil. Monthly surveys of larvae and adults were conducted between 2008 and 2011 at approximately 1000 m altitude on their respective host plants, Cordia
polycephala (Boraginaceae), Ipomoea
philomega (Convolvulaceae) and Solanum
scuticum (Solanaceae). This is the first observation of larviparity and host record for Platyphora
axillaris. Although having different life history traits, all species showed similar phenologies. They were abundant from October to March, months of high temperatures and intense rainfall, with two distinct reproductive peaks in the same season. Abundance dropped abruptly during the coldest and driest months, from May to August. Frequently none of these species were recorded during June and July. This phenological pattern is similar to other Chrysomelidae living in subtropical areas of Brazil. Temperature and rainfall appear to be the major factors influencing the fluctuation of these three species. 相似文献
119.
Subacute calorie restriction and rapamycin discordantly alter mouse liver proteome homeostasis and reverse aging effects 下载免费PDF全文
Dao‐Fu Dai Ying A. Chiao Ellen K. Quarles Edward J. Hsieh David Crispin Jason H. Bielas Nolan G. Ericson Richard P. Beyer Vivian L. MacKay Michael J. MacCoss Peter S. Rabinovitch 《Aging cell》2015,14(4):547-557
Calorie restriction (CR) and rapamycin (RP) extend lifespan and improve health across model organisms. Both treatments inhibit mammalian target of rapamycin (mTOR) signaling, a conserved longevity pathway and a key regulator of protein homeostasis, yet their effects on proteome homeostasis are relatively unknown. To comprehensively study the effects of aging, CR, and RP on protein homeostasis, we performed the first simultaneous measurement of mRNA translation, protein turnover, and abundance in livers of young (3 month) and old (25 month) mice subjected to 10‐week RP or 40% CR. Protein abundance and turnover were measured in vivo using 2H3–leucine heavy isotope labeling followed by LC‐MS/MS, and translation was assessed by polysome profiling. We observed 35–60% increased protein half‐lives after CR and 15% increased half‐lives after RP compared to age‐matched controls. Surprisingly, the effects of RP and CR on protein turnover and abundance differed greatly between canonical pathways, with opposite effects in mitochondrial (mt) dysfunction and eIF2 signaling pathways. CR most closely recapitulated the young phenotype in the top pathways. Polysome profiles indicated that CR reduced polysome loading while RP increased polysome loading in young and old mice, suggesting distinct mechanisms of reduced protein synthesis. CR and RP both attenuated protein oxidative damage. Our findings collectively suggest that CR and RP extend lifespan in part through the reduction of protein synthetic burden and damage and a concomitant increase in protein quality. However, these results challenge the notion that RP is a faithful CR mimetic and highlight mechanistic differences between the two interventions. 相似文献
120.
Zeng N Li Y He L Xu X Galicia V Deng C Stiles BL 《Molecular cancer research : MCR》2011,9(12):1708-1717
The α-subunit of eukaryotic initiation factor 2 (eIF2α) is a key translation regulator that plays an important role in cellular stress responses. In the present study, we investigated how eIF2α phosphorylation can be regulated by a tumor suppressor PTEN (phosphatase and tensin homolog deleted on chromosome 10) and how such regulation is used by PTEN-deficient hepatocytes to adapt and cope with oxidative stress. We found that eIF2α was hyperphosphorylated when Pten was deleted, and this process was AKT dependent. Consistent with this finding, we found that the Pten-null cells developed resistance to oxidative glutamate and H(2)O(2)-induced cellular toxicity. We showed that the messenger level of CReP (constitutive repressor of eIF2α phosphorylation), a constitutive phosphatase of eIF2α, was downregulated in Pten-null hepatocytes, providing a possible mechanism through which PTEN/AKT pathway regulates eIF2α phosphorylation. Ectopic expression of CReP restored the sensitivity of the Pten mutant hepatocytes to oxidative stress, confirming the functional significance of the downregulated CReP and upregulated phospho-eIF2α in the resistance of Pten mutant hepatocytes to cellular stress. In summary, our study suggested a novel role of PTEN in regulating stress response through modulating the CReP/eIF2α pathway. 相似文献