全文获取类型
收费全文 | 550篇 |
免费 | 43篇 |
出版年
2023年 | 5篇 |
2022年 | 6篇 |
2021年 | 26篇 |
2020年 | 10篇 |
2019年 | 34篇 |
2018年 | 22篇 |
2017年 | 17篇 |
2016年 | 25篇 |
2015年 | 36篇 |
2014年 | 43篇 |
2013年 | 36篇 |
2012年 | 30篇 |
2011年 | 37篇 |
2010年 | 22篇 |
2009年 | 21篇 |
2008年 | 33篇 |
2007年 | 28篇 |
2006年 | 21篇 |
2005年 | 21篇 |
2004年 | 11篇 |
2003年 | 24篇 |
2002年 | 18篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 10篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有593条查询结果,搜索用时 62 毫秒
1.
2.
3.
4.
Matteo Pappalardo Nir Shachaf Livia Basile Danilo Milardi Mouhammed Zeidan Jamal Raiyn Salvatore Guccione Anwar Rayan 《PloS one》2014,9(10)
The human histamine H4 receptor (hH4R), a member of the G-protein coupled receptors (GPCR) family, is an increasingly attractive drug target. It plays a key role in many cell pathways and many hH4R ligands are studied for the treatment of several inflammatory, allergic and autoimmune disorders, as well as for analgesic activity. Due to the challenging difficulties in the experimental elucidation of hH4R structure, virtual screening campaigns are normally run on homology based models. However, a wealth of information about the chemical properties of GPCR ligands has also accumulated over the last few years and an appropriate combination of these ligand-based knowledge with structure-based molecular modeling studies emerges as a promising strategy for computer-assisted drug design. Here, two chemoinformatics techniques, the Intelligent Learning Engine (ILE) and Iterative Stochastic Elimination (ISE) approach, were used to index chemicals for their hH4R bioactivity. An application of the prediction model on external test set composed of more than 160 hH4R antagonists picked from the chEMBL database gave enrichment factor of 16.4. A virtual high throughput screening on ZINC database was carried out, picking ∼4000 chemicals highly indexed as H4R antagonists'' candidates. Next, a series of 3D models of hH4R were generated by molecular modeling and molecular dynamics simulations performed in fully atomistic lipid membranes. The efficacy of the hH4R 3D models in discrimination between actives and non-actives were checked and the 3D model with the best performance was chosen for further docking studies performed on the focused library. The output of these docking studies was a consensus library of 11 highly active scored drug candidates. Our findings suggest that a sequential combination of ligand-based chemoinformatics approaches with structure-based ones has the potential to improve the success rate in discovering new biologically active GPCR drugs and increase the enrichment factors in a synergistic manner. 相似文献
5.
Jamal T. Manassah 《Plasmonics (Norwell, Mass.)》2016,11(4):995-1002
I compute the transmission coefficient as function of the incident light frequency for a system consisting of a dielectric slab doped with silver nano-spheres sandwiched between two silver parallel plates. Then, I analyze the details of the transmission spectrum identifying the coupled plasmons from the two (doped dielectric and plates) subsystems which dominate the system’s dynamics. 相似文献
6.
7.
Khuram Shahzad Abdul Hai Nadeem Kizilbash Jawaria Ambreen Jamal Alruwaili 《Bioinformation》2013,9(9):471-476
DNA γ is approximately half of the size of Begomovirus DNA. It encodes a γC1 gene that is conserved in position and size. This
gene has the capacity to encode a 13 to 14 kDa protein comprising 118 amino acid residues. It has been shown earlier that γC1
protein is necessary for inducing symptoms of cotton leaf curl disease. The structure for γC1 (CLCuDγ01-Pakistan) is still
unknown. Therefore, a model of γC1 (CLCuDγ01-Pakistan) was developed using DoBo and I-TASSER servers followed by
validation by PROCHECK and VERIFY 3D servers. The developed model provides an insight in a role for this multifunctional
protein in causing Cotton Leaf Curl Disease (CLCuD). A possible function of this protein might be the suppression of RNAsilencing
in cotton plants. 相似文献
8.
Calum Brown Dave Murray-Rust Jasper van Vliet Shah Jamal Alam Peter H. Verburg Mark D. Rounsevell 《PloS one》2014,9(12)
The globalisation of trade affects land use, food production and environments around the world. In principle, globalisation can maximise productivity and efficiency if competition prompts specialisation on the basis of productive capacity. In reality, however, such specialisation is often constrained by practical or political barriers, including those intended to ensure national or regional food security. These are likely to produce globally sub-optimal distributions of land uses. Both outcomes are subject to the responses of individual land managers to economic and environmental stimuli, and these responses are known to be variable and often (economically) irrational. We investigate the consequences of stylised food security policies and globalisation of agricultural markets on land use patterns under a variety of modelled forms of land manager behaviour, including variation in production levels, tenacity, land use intensity and multi-functionality. We find that a system entirely dedicated to regional food security is inferior to an entirely globalised system in terms of overall production levels, but that several forms of behaviour limit the difference between the two, and that variations in land use intensity and functionality can substantially increase the provision of food and other ecosystem services in both cases. We also find emergent behaviour that results in the abandonment of productive land, the slowing of rates of land use change and the fragmentation or, conversely, concentration of land uses following changes in demand levels. 相似文献
9.
10.
Samar O. Rabah Bikash Shrestha Nahid H. Hajrah Mumdooh J. Sabir Hesham F. Alharby Mernan J. Sabir Alawiah M. Alhebshi Jamal S.M. Sabir Lawrence E. Gilbert Tracey A. Ruhlman Robert K. Jansen 《植物分类学报:英文版》2019,57(1):1-14
Although past studies have included Passiflora among angiosperm lineages with highly rearranged plastid genomes (plastomes), knowledge about plastome organization in the genus is limited. So far only one draft and one complete plastome have been published. Expanded sampling of Passiflora plastomes is needed to understand the extent of the genomic rearrangement in the genus, which is also unusual in having biparental plastid inheritance and plastome‐genome incompatibility. We sequenced 15 Passiflora plastomes using either Illumina paired‐end or shotgun cloning and Sanger sequencing approaches. Assembled plastomes were annotated using Dual Organellar GenoMe Annotator (DOGMA) and tRNAscan‐SE. The Populus trichocarpa plastome was used as a reference to estimate genomic rearrangements in Passiflora by performing whole genome alignment in progressiveMauve. The phylogenetic distribution of rearrangements was plotted on the maximum likelihood tree generated from 64 plastid encoded protein genes. Inverted repeat (IR) expansion/contraction and loss of the two largest hypothetical open reading frames, ycf1 and ycf2, account for most plastome size variation, which ranges from 139 262 base pairs (bp) in P. biflora to 161 494 bp in P. pittieri. Passiflora plastomes have experienced numerous inversions, gene and intron losses along with multiple independent IR expansions and contractions resulting in a distinct organization in each of the three subgenera examined. Each Passiflora subgenus has a unique plastome structure in terms of gene content, order and size. The phylogenetic distribution of rearrangements shows that Passiflora has experienced widespread genomic changes, suggesting that such events may not be reliable phylogenetic markers. 相似文献