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91.
Yi Kong Tianhua Yan Feifei Feng Jianmin Bian Yan Yang Haining Yu 《Journal of peptide science》2011,17(7):540-544
The defensin‐like antimicrobial peptides have been characterized from various other arthropods including insects, scorpions, and ticks. But no natural spider defensin‐like antimicrobial peptides have ever been isolated from spiders, except couple of cDNA and DNA sequences of five spider species revealed by previous genomic study. In this work, a defensin‐like antimicrobial peptide named Oh‐defensin was purified and characterized from the venoms of the spider, Ornithoctonus hainana. Oh‐defensin is composed of 52 amino acid (aa) residues including six Cys residues that possibly form three disulfide bridges. Its aa sequence is MLCKLSMFGAVLGV PACAIDCLPMGKTGGSCEGGVCGCRKLTFKILWDKKFG. By BLAST search, Oh‐defensin showed significant sequence similarity to other arthropod antimicrobial peptides of the defensin family. Oh‐defensin exerted potent antimicrobial activities against tested microorganisms including Gram‐positive bacteria, Gram‐negative bacteria, and fungi. The cDNA encoding Oh‐defensin precursor was also cloned from the cDNA library of O. hainana. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
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Jing-Jing Wang Wen Sun Wei-Dong Jia Ming Bian Li-Jun Yu 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2304
Oxadiazole is a five-membered heterocyclic compound containing two nitrogen atoms and one oxygen atom. The 1,3,4-oxadiazole and 1,2,4-oxadiazole have favourable physical, chemical, and pharmacokinetic properties, which significantly increase their pharmacological activity via hydrogen bond interactions with biomacromolecules. In recent years, oxadiazole has been demonstrated to be the biologically active unit in a number of compounds. Oxadiazole derivatives exhibit antibacterial, anti-inflammatory, anti-tuberculous, anti-fungal, anti-diabetic and anticancer activities. In this paper, we report a series of compounds containing oxadiazole rings that have been published in the last three years only (2020–2022) as there was no report or their activities described in any article in 2019, which will be useful to scientists in research fields of organic synthesis, medicinal chemistry, and pharmacology. 相似文献
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Jing Chen Jialin Meng Yi Liu Zichen Bian Qingsong Niu Junyi Chen Jun Zhou Li Zhang Meng Zhang Chaozhao Liang 《Journal of cellular and molecular medicine》2022,26(21):5379
To identify prostate cancer (PCa) patients with a high risk of recurrence is critical before delivering adjuvant treatment. We developed a classifier based on the Enzalutamide treatment resistance‐related genes to assist the currently available staging system in predicting the recurrence‐free survival (RFS) prognosis of PCa patients. We overlapped the DEGs from two datasets to obtain a more convincing Enzalutamide‐resistance‐related‐gene (ERRG) cluster. The five‐ERRG‐based classifier obtained good predictive values in both the training and validation cohorts. The classifier precisely predicted RFS of patients in four cohorts, independent of patient age, pathological tumour stage, Gleason score and PSA levels. The classifier and the clinicopathological factors were combined to construct a nomogram, which had an increased predictive accuracy than that of each variable alone. Besides, we also compared the differences between high‐ and low‐risk subgroups and found their differences were enriched in cancer progression‐related pathways. The five‐ERRG‐based classifier is a practical and reliable predictor, which adds value to the existing staging system for predicting the RFS prognosis of PCa after radical prostatectomy, enabling physicians to make more informed treatment decisions concerning adjuvant therapy. 相似文献
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Huang-Ping Wang Ying Zhao Shao-Min Bian Hui-Na Zhou Zhi-Gang Zhang Jin-Mao Zhu Ju-Fu Huang 《植物学报(英文版)》2006,48(5):567-572
nifB-MoFe protein (nifB-Av1), AnifE MoFe protein (△nifE Av1) and AnifZ MoFe protein (△nifZ Av1) were obtained by chromatography on DE52, Sephacryl S-300 and Q-Sepharose columns from nifB point-mutated, nifE deleted and nifZ deleted mutant stains (UW45, DJ35 and DJ194) of Azotobacter vinelandii Llpmann, respectively. When complemented with nltrogenase Fe protein (Av2), AnifZ Av1 had partial activity and both nifB-Avl and △nifE Av1 had hardly any activity, but could be obviously activated by FeMoco extracted from wild-type MoFe protein (OP Av1) or △nifZ Av1. After being Incubated with excess O-phenanthrollne (O-phen) for 150 mln at 30 ℃ and subjected to chromatography on a Sephadex G-25 column In an Ar atmosphere, nifB- Av1C, △nifE Av1C and △nifZ Av1C were obtained, respectively. Based on a calculation of Fe atoms In the Ophen-Fe compound with ε 512nm = 11 100, lost Fe atoms of nifB-Av1, △nifE Av1 and △nifZ Av1 were estimated to be 1.35, 2.89 and 8.44 per molecule of protein, respectively. As a result of the Fe loss, △nifZ Av1 loses Its original activity. In the presence of both MgATP and Av2, these Fe-loslng proteins, but not the original proteins untreated with O-phen, could be significantly activated by reconstltuent solution (RS) composed of dlthlothreltol, ferric homocltrate, Na2S and Na2MoO4, or K2CrO4, or KMnO4. But In the absence of MgATP or Av2, the activation did not occur, with the exception that △nifZ AvlC was partially activated, and the activity was only 17%. These findings Indicate that: (I) △nifZ Avl with half P-cluster content Is somewhat different from FeMoco-deflclent nifB-Avl and ,△nifE Av1 with respect to protein conformation either before or after treatment with O-phen; (11) full activation of these proteins with RS requires pretreatment with O-phen and the simultaneous presence of MgATP and Av2. 相似文献
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Second intron of mouse nestin gene directs its expression in pluripotent embryonic carcinoma cells through POU factor binding site 总被引:4,自引:0,他引:4
Jin ZG Liu L Zhong H Zhang KJ Chen YF Bian W Cheng LP Jing NH 《Acta biochimica et biophysica Sinica》2006,38(3):207-212
Nestin,an intermediate filament protein,is expressed in the neural stem cells of the developingcentral nervous system.This tissue-specific expression is driven by the neural stem cell-specific enhancer inthe second intron of the nestin gene.In this study,we showed that the mouse nestin gene was expressed inpluripotent embryonic carcinoma (EC) P19 and F9 cells,not in the differentiated cell types.This cell type-specific expression was conferred by the enhancer in the second intron.Mutation of the conserved POUfactor-binding site in the enhancer abolished the reporter gene expression in EC cells.Oct4,a Class V POUfactor,was found to be coexpressed with nestin in EC cells.Electrophoretic mobility-shift assays and supershiftassays showed that a unique protein-DNA complex was formed specifically with nuclear extracts of ECcells,and Oct4 protein was included.Together,these results suggest the functional relevance between theconserved POU factor-binding site and the expression of the nestin gene in pluripotent EC cells. 相似文献