全文获取类型
收费全文 | 1180篇 |
免费 | 85篇 |
出版年
2023年 | 5篇 |
2022年 | 23篇 |
2021年 | 32篇 |
2020年 | 14篇 |
2019年 | 21篇 |
2018年 | 34篇 |
2017年 | 19篇 |
2016年 | 25篇 |
2015年 | 65篇 |
2014年 | 64篇 |
2013年 | 84篇 |
2012年 | 93篇 |
2011年 | 118篇 |
2010年 | 55篇 |
2009年 | 44篇 |
2008年 | 63篇 |
2007年 | 78篇 |
2006年 | 76篇 |
2005年 | 83篇 |
2004年 | 60篇 |
2003年 | 61篇 |
2002年 | 35篇 |
2001年 | 10篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 5篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1973年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1954年 | 1篇 |
1946年 | 1篇 |
1925年 | 1篇 |
排序方式: 共有1265条查询结果,搜索用时 15 毫秒
91.
92.
93.
Georgios Hadjigeorgiou Efthimios Dardiotis Georgios Tsivgoulis Triantafyllos Doskas Damianos Petrou Nikolaos Makris Nikolaos Vlaikidis Thomas Thomaidis Athanasios Kyritsis Nikolaos Fakas Xoulietta Treska Clementine Karageorgiou Stefania Sotirli Christos Giannoulis Dimitra Papadimitriou Ioannis Mylonas Evaggelos Kouremenos George S. Vlachos Dimitrios Georgiopoulos Despoina Mademtzoglou Michalis Vikelis Elias Zintzaras 《PloS one》2015,10(10)
94.
Chryssa Anastasiadou Christos Gkenas Ifigenia Kagalou Ioannis D. Leonardos 《Biologia》2014,69(7):895-904
In order to have a comprehensive evaluation and classification of the natural biota of Lake Pamvotis, the present study aims at investigating shrimps’ bionomic traits. Information on shrimps’ habitat preferences, abundances, and syntopic species in relation to the physicochemical profile of the lake’s water are investigated for the first time. The study was carried out on a bi-monthly base, at six littoral sites of the lake. Samples’ study from different habitats and seasons revealed that the freshwater shrimp Atyaephyra thyamisensis was the most abundant species, accounting for 44.76% of the total taxa catch, while the grass shrimp Palaemonetes antennarius was less abundant (7.54%). Syntopic fish species in the littoral zone of Lake Pamvotis such as Economidichthys pygmaeus, Gambusia holbrooki, Knipowitschia caucasica and Rutillus panosi showed interannual differences with abundances of 24.12%, 19.13%, 4.26% and 0.20%, respectively. Correspondence analysis revealed clear patterns between species and stations. A. thyamisensis was predominant in shallow, well oxygenated water bodies rich with aquatic vegetation, but it was absent from deeper habitats. P. antennarius was found mainly in lentic water bodies, rocky substratum and deeper habitats. Taking into account the high ecological importance of the freshwater shrimps in ecosystems’ energy flow, ecological and biological data of lake’s shrimps are discussed and presented thoroughly. Threats and conservation measures for both shrimp species are debated also in detail. 相似文献
95.
Richard Ward Christos Pliotas Emma Branigan Christian Hacker Akiko Rasmussen Gregor Hagelueken Ian R. Booth Samantha Miller John Lucocq James H. Naismith Olav Schiemann 《Biophysical journal》2014
Mechanosensitive channel proteins are important safety valves against osmotic shock in bacteria, and are involved in sensing touch and sound waves in higher organisms. The mechanosensitive channel of small conductance (MscS) has been extensively studied. Pulsed electron-electron double resonance (PELDOR or DEER) of detergent-solubilized protein confirms that as seen in the crystal structure, the outer ring of transmembrane helices do not pack against the pore-forming helices, creating an apparent void. The relevance of this void to the functional form of MscS in the bilayer is the subject of debate. Here, we report PELDOR measurements of MscS reconstituted into two lipid bilayer systems: nanodiscs and bicelles. The distance measurements from multiple mutants derived from the PELDOR data are consistent with the detergent-solution arrangement of the protein. We conclude, therefore, that the relative positioning of the transmembrane helices is preserved in mimics of the cell bilayer, and that the apparent voids are not an artifact of detergent solution but a property of the protein that will have to be accounted for in any molecular mechanism of gating. 相似文献
96.
Stelios F. Assimakopoulos Athanassios C. Tsamandas Christos D. Georgiou Constantine E. Vagianos Chrisoula D. Scopa 《Peptides》2010,31(12):2294-2303
The regenerative capacity of the cholestatic liver is significantly attenuated. Oval cells are hepatic stem cells involved in liver's regeneration following diverse types of injury. The present study investigated the effect of the neuropeptides bombesin (BBS) and neurotensin (NT) on oval cell proliferation as well as on hepatocyte and cholangiocyte proliferation and apoptosis in the cholestatic rat liver. Seventy male Wistar rats were randomly divided into five groups: controls, sham operated, bile duct ligated (BDL), BDL + BBS (30 μg/kg/d), BDL + NT (300 μg/kg/d). Ten days later, alpha-fetoprotein (AFP) mRNA (in situ hybridization), cytokeratin-19 and Ki67 antigen expression (immunohistochemistry) and apoptosis (TUNEL) were evaluated on liver tissue samples. Cells with morphologic features of oval cells that were cytokeratin-19(+) and AFP mRNA(+) were scored in morphometric analysis and their proliferation was recorded. In addition, the proliferation and apoptotic rates of hepatocytes and cholangiocytes were determined. Alanine aminotransferase (ALT) levels and hepatic oxidative stress (lipid peroxidation and glutathione redox state) were also estimated. The neuropeptides BBS and NT significantly reduced ALT levels and hepatic oxidative stress. Both agents exerted similar and cell type-specific effects on oval cells, hepatocytes and cholangiocytes: (a) oval cell proliferation and accumulation in the cholestatic liver was attenuated, (b) hepatocyte proliferation was increased along with a decreased rate of their apoptosis and (c) cholangiocyte proliferation was attenuated and their apoptosis was increased. These observations might be of potential value in patients with extrahepatic cholestasis. 相似文献
97.
Sarah E. Ross Alan R. Mardinly Alejandra E. McCord Jonathan Zurawski Sonia Cohen Cynthia Jung Linda Hu Stephanie I. Mok Anar Shah Erin M. Savner Christos Tolias Roman Corfas Suzhen Chen Perrine Inquimbert Yi Xu Roderick R. McInnes Frank L. Rice Gabriel Corfas Qiufu Ma Clifford J. Woolf Michael E. Greenberg 《Neuron》2010,65(6):886-898
98.
ATP provided by oxidative phosphorylation supports highly complex and energetically expensive cellular processes. Yet, in several pathological settings, mitochondria could revert to ATP consumption, aggravating an existing cellular pathology. Here we review (i) the pathological conditions leading to ATP hydrolysis by the reverse operation of the mitochondrial FoF1-ATPase, (ii) molecular and thermodynamic factors influencing the directionality of the FoF1-ATPase, (iii) the role of the adenine nucleotide translocase as the intermediary adenine nucleotide flux pathway between the cytosol and the mitochondrial matrix when mitochondria become ATP consumers, (iv) the role of the permeability transition pore in bypassing the ANT, thereby allowing the flux of ATP directly to the hydrolyzing FoF1-ATPase, (v) the impact of the permeability transition pore on glycolytic ATP production, and (vi) endogenous and exogenous interventions for limiting ATP hydrolysis by the mitochondrial FoF1-ATPase. 相似文献
99.
Christos Gournas Sotiris Amillis Anna Vlanti George Diallinas 《Molecular microbiology》2010,75(1):246-260
In this work we unmask a novel downregulation mechanism of the uric acid/xanthine transporter UapA, the prototype member of the ubiquitous Nucleobase-Ascorbate Transporter family, directly related to its function. In the presence of substrates, UapA is endocytosed, sorted into the multivesicular body pathway and degraded in vacuoles. Substrate-induced endocytosis, unlike ammonium-induced turnover, is absolutely dependent on UapA activity and several lines of evidence showed that the signal for increased endocytosis is the actual translocation of substrates through the UapA protein. The use of several UapA functional mutants with altered kinetics and specificity has further shown that transport-dependent UapA endocytosis occurs through a mechanism, which senses subtle conformational changes associated with the transport cycle. We also show that distinct mechanisms of UapA endocytosis necessitate ubiquitination of a single Lys residue (K572) by HulARsp5 . Finally, we demonstrate that in the presence of substrates, non-functional UapA versions can be endocytosed in trans if expressed in the simultaneous presence of active UapA versions, even if the latter cannot be endocytosed themselves. 相似文献
100.
Marina Roussaki Christos A. Kontogiorgis Dimitra Hadjipavlou-Litina Stylianos Hamilakis Anastasia Detsi 《Bioorganic & medicinal chemistry letters》2010,20(13):3889-3892
A series of coumarin analogues bearing a substituted phenyl ring on position 3 were synthesized via a novel methodology, through an intermolecular condensation reaction of 2-hydroxyacetophenones and 2-hydroxybenzaldehyde, with imidazolyl phenylacetic acid active intermediates. The in vitro antioxidant activity of the synthesized compounds was evaluated using two different antioxidant assays (radical scavenging ability of DPPH stable free radical and inhibition of lipid peroxidation induced by the thermal free radical AAPH). Moreover, the ability of the compounds to inhibit soybean lipoxygenase was determined as an indication of potential anti-inflammatory activity. 相似文献