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991.
Mass spectrometry not only plays a crucial role in the identification of proteins involved in the intricate interaction networks of the cell, but also is increasingly involved in the characterization of the non-covalent complexes formed by interacting partners. Recent developments have enabled the use of gas phase dissociation to probe oligomeric organization and topology, and increased understanding of the electrospray process is leading to knowledge of the structure of protein assemblies both in solution and in the gas phase. 相似文献
992.
Effect of formic acid exposure on keratin fiber derived from poultry feather biomass 总被引:1,自引:0,他引:1
Converting poultry feather biomass into useful products presents a new avenue of utilization of agricultural waste material. However, not much is understood about the poultry feather structure or methods to process it. In this study, formic acid vapor is systematically allowed to penetrate the feather fiber structure, which is composed of keratin. The diffusion kinetics show Fickian behavior during absorption. After very long times, i.e., greater than 10(3)h, the absorption experiments are stopped and the formic acid is allowed to desorb from the keratin material. The desorption kinetics of formic acid out of the keratin fiber do not mirror the absorption kinetics, indicating a change in the keratin microstructure. DSC and NMR spectroscopy analyses on the keratin fiber show a reduction in the area of the crystalline melting peak and solubilization of amino acids upon formic acid exposure. This indicates that the crystallinity is disrupted resulting in more amorphous fraction in the keratin polymer. 相似文献
993.
Warshakoon NC Wu S Boyer A Kawamoto R Sheville J Renock S Xu K Pokross M Zhou S Winter C Walter R Mekel M Evdokimov AG 《Bioorganic & medicinal chemistry letters》2006,16(21):5517-5522
A new series of potent 8-hydroxyquinolines was designed based on the newly resolved X-ray crystal structure of EGLN-1. Both alkyl and aryl 8-hydroxyquinoline-7-carboxyamides were good HIF-1alpha prolyl hydroxylase (EGLN) inhibitors. In subsequent VEGF induction assays, these exhibited potent VEGF activity. In addition, this class of compounds did show the ability to stabilize HIF-1alpha. 相似文献
994.
Warshakoon NC Sheville J Bhatt RT Ji W Mendez-Andino JL Meyers KM Kim N Wos JA Mitchell C Paris JL Pinney BB Reizes O Hu XE 《Bioorganic & medicinal chemistry letters》2006,16(19):5207-5211
A novel series of substituted quinoline analogs were designed and synthesized as potent and selective melanin concentrating hormone (MCH) antagonists. These analogs show potent (nM) activity (12a-k) with a moderate selectivity. Conversely, the conformationally constrained thienopyrimidinone analogs (18a-g) showed improved activity in MCH-1R and selectivity over 5HT2C. 相似文献
995.
Zhou D Chu W Rothfuss J Zeng C Xu J Jones L Welch MJ Mach RH 《Bioorganic & medicinal chemistry letters》2006,16(19):5041-5046
A non-peptide-based isatin sulfonamide analog, WC-II-89, was synthesized and its inhibition toward recombinant human caspase-3 and other caspases was determined. This compound showed high potency for inhibiting caspase-3 and -7, and high selectivity against caspases-1, -6, and -8. [(18)F]WC-II-89 was synthesized via a nucleophilic substitution of the corresponding mesylate precursor in high yield and radiochemical purity. Biodistribution studies using [(18)F]WC-II-89 revealed higher uptake in liver and spleen of cycloheximide-treated rats, an animal model of apoptosis, relative to control animals. Western blot analysis confirmed the presence of activated caspase-3 in the liver and spleen of cycloheximide-treated animals. MicroPET imaging studies revealed a high uptake of the radiotracer in the liver of a cycloheximide-treated rat relative to the untreated control. These data suggest that [(18)F]WC-II-89 is a potential radiotracer for imaging caspase-3 activation in tissues undergoing apoptosis. 相似文献
996.
Naidu BN Sorenson ME Matiskella JD Li W Sausker JB Zhang Y Connolly TP Lam KS Bronson JJ Pucci MJ Yang H Ueda Y 《Bioorganic & medicinal chemistry letters》2006,16(13):3545-3549
Stereoselective reduction of dehydroalanine double bond in nocathiacin I afforded the primary amide 2. Enzymatic hydrolysis of the amide 2 provided the carboxylic acid 3, which upon coupling with a variety of amines furnished amides 4-32. Some of these semi-synthetic derivatives have retained very good antibacterial activity and have improved aqueous solubility. 相似文献
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