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201.
Yang Li Longyu Hou Bing Song Shiqiang Wan Xiaoqin Sun Linghao Li 《Journal of Plant Ecology》2019,12(4):742
Aims
Precipitation is predicted to increase in arid and semiarid regions under climate change, with greater changes in intra- and inter-annual distribution in the future. As a major limiting factor in these regions, changes in precipitation undoubtedly influence plant growth and productivity. However, how the temporal shifts in precipitation will impact plant populations are uncertain. 相似文献
202.
Abdul Rahman Amirah Mokhtar Norfilza Mohd Harun Roslan Jamal Rahman Wan Ngah Wan Zurinah 《Journal of physiology and biochemistry》2019,75(4):499-517
Journal of Physiology and Biochemistry - Gamma-tocotrienol (GTT) and hydroxychavicol (HC) exhibit anticancer activity in glioma cancer cells, where the combination of GTT + HC was shown to be more... 相似文献
203.
Samarjit Patnaik Dipanwita Basu Noel Southall Seameen Dehdashti Kanny K. Wan Wei Zheng Marc Ferrer Mercedes Taylor Daniel A. Engel Juan Jose Marugan 《Bioorganic & medicinal chemistry letters》2019,29(9):1113-1119
Nonstructural protein 1 (NS1) plays a crucial function in the replication, spread, and pathogenesis of influenza virus by inhibiting the host innate immune response. Here we report the discovery and optimization of novel pyrazolopyridine NS1 antagonists that can potently inhibit influenza A/PR/8/34 replication in MDCK cells, rescue MDCK cells from cytopathic effects of seasonal influenza A strains, reverse NS1-dependent inhibition of IFN-β gene expression, and suppress the slow growth phenotype in NS1-expressing yeast. These pyrazolopyridines will enable researchers to investigate NS1 function during infection and how antagonists can be utilized in the next generation of treatments for influenza infection. 相似文献
204.
Yalan Guo Ke Wang Xiaoyu Chen Haihong Li Qi Wan Susan Morris-Natschke Kuo-Hsiung Lee Ying Chen 《Bioorganic & medicinal chemistry letters》2019,29(1):28-31
Twenty-five seco-4-methyl-DCK derivatives were designed, synthesized and evaluated for chemoreversal activity when combined with paclitaxel or vincristine in two drug-resistant cancer cell lines (A2780/T and KB-V) respectively. Most of the new compounds displayed moderate to significant MDR reversal activities in the P-gp overexpressing A2780/T and KB-V cells. Especially, compounds 7o and 7y showed the most potent chemosensitization activities with more than 496 and 735 reversal ratios at a concentration of 10?μM. Unexpectedly the newly synthesized compounds did not show chemosensitization activities observed in a non-P-gp overexpressing cisplatin resistant human ovarian cancer cell line (A2780/CDDP), implying that the MDR reversal effects might be associated with P-gp overexpression. Moreover, these compounds did not exhibit significant antiproliferative activities against nontumorigenic cell lines (HUVEC, HOSEC and T29) compared to the positive control verapamil at the tested concentration, which suggested better safety than verapamil. The pharmacological actions of the compounds will be studied further to explore their merit for development as novel candidates to overcome P-gp mediated MDR cancer. 相似文献
205.
Shan Xiao Lin Wei Zongqin Hong Li Rao Yanliang Ren Jian Wan Lingling Feng 《Bioorganic & medicinal chemistry》2019,27(5):805-812
By using a new Fragment-Based Virtual Screen strategy, two series of novel FBA-II inhibitors (thiourea derivatives) were de novo discovered based on the active site of fructose-1, 6-bisphosphate aldolase from Cyanobacterial (CyFBA). In comparison, most of the N-(2-benzoylhydrazine-1-carbonothioyl) benzamide derivatives (L14~L22) exhibit higher CyFBA-II inhibitory activities compared to N-(phenylcarbamothioyl) benzamide derivatives (L1~L13). Especially, compound L14 not only shows higher CyFBA-II activity (Ki?=?0.65?μM), but also exhibits most potent in vivo activity against Synechocystis sp. PCC 6803 (EC50?=?0.09?ppm), higher (7-fold) than that of our previous inhibitor (EC50?=?0.6?ppm). The binding modes of compound L14 and CyFBA-II were further elucidated by jointly using DOX computational protocol, MM-PBSA and site-directed mutagenesis assays. The positive results suggest that strategy adopted in this study was promising to rapidly discovery the potent inhibitors with novel scaffolds. The satisfactory algicide activities suggest that the thiourea derivatives is very likely to be a promising lead for the development of novel specific algicides to solve Cyanobacterial harmful algal blooms (CHABs). 相似文献
206.
Mammalian Genome - Increasing evidence shows that miRNAs play pivotal roles in cardiovascular diseases, including heart failure (HF). The aim of this study was to investigate the role of miR-129-5p... 相似文献
207.
208.
Britt Paulsen Kim Alex Fredriksen Dirk Petersen Louis Maes An Matheeussen Ali-Oddin Naemi Anne Aamdal Scheie Roger Simm Rui Ma Baojie Wan Scott Franzblau Lise-Lotte Gundersen 《Bioorganic & medicinal chemistry》2019,27(4):620-629
(+)-N6-Hydroxyagelasine D, the enantiomer of the proposed structure of (?)-ageloxime D, as well as N6-hydroxyagelasine analogs were synthesized by selective N-7 alkylation of N6-[tert-butyl(dimethyl)silyloxy]-9-methyl-9H-purin-6-amine in order to install the terpenoid side chain, followed by fluoride mediated removal of the TBDMS-protecting group. N6-Hydroxyagelasine D and the analog carrying a geranylgeranyl side chain displayed profound antimicrobial activities against several pathogenic bacteria and protozoa and inhibited bacterial biofilm formation. However these compounds were also toxic towards mammalian fibroblast cells (MRC-5). The spectral data of N6-hydroxyagelasine D did not match those reported for ageloxime D before. Hence, a revised structure of ageloxime D was proposed. Basic hydrolysis of agelasine D gave (+)-N-[4-amino-6-(methylamino)pyrimidin-5-yl]-N-copalylformamide, a compound with spectral data in full agreement with those reported for (?)-ageloxime D. 相似文献
209.
Yang Wan Jean‐Pierre Baltaze Cyrille Kouklovsky Emeric Miclet Valrie Alezra 《Journal of peptide science》2019,25(2)
We have previously reported the synthesis of enantiopure β,γ‐diamino acids and relevant short α/γ‐peptide containing such building blocks. Complete nuclear magnetic resonance (NMR) studies, together with molecular modeling, highlighted the ability of a β,γ‐diamino acid to induce various intramolecular turns. In this paper, we describe for the first time the formation of a dimeric structure constituted by α/γ/α‐tripeptide and stabilized by intermolecular interactions. A structural model is proposed based on extensive NMR measurements. 相似文献
210.
Li Wan Markus Koeck Simon J. Williams Anthony R. Ashton Gregory J. Lawrence Hitoshi Sakakibara Mikiko Kojima Christine Böttcher Daniel J. Ericsson Adrienne R. Hardham David A. Jones Jeffrey G. Ellis Bostjan Kobe Peter N. Dodds 《Molecular Plant Pathology》2019,20(2):211-222
During infection, plant pathogens secrete effector proteins to facilitate colonization. In comparison with our knowledge of bacterial effectors, the current understanding of how fungal effectors function is limited. In this study, we show that the effector AvrL567-A from the flax rust fungus Melampsora lini interacts with a flax cytosolic cytokinin oxidase, LuCKX1.1, using both yeast two-hybrid and in planta bimolecular fluorescence assays. Purified LuCKX1.1 protein shows catalytic activity against both N6-(Δ2-isopentenyl)-adenine (2iP) and trans-zeatin (tZ) substrates. Incubation of LuCKX1.1 with AvrL567-A results in increased catalytic activity against both substrates. The crystal structure of LuCKX1.1 and docking studies with AvrL567-A indicate that the AvrL567 binding site involves a flexible surface-exposed region that surrounds the cytokinin substrate access site, which may explain its effect in modulating LuCKX1.1 activity. Expression of AvrL567-A in transgenic flax plants gave rise to an epinastic leaf phenotype consistent with hormonal effects, although no difference in overall cytokinin levels was observed. We propose that, during infection, plant pathogens may differentially modify the levels of extracellular and intracellular cytokinins. 相似文献