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961.
962.
Background  Carboxylesterase (CES) is predominantly responsible for the detoxification of a wide range of drugs and narcotics, and catalyze several reactions in cholesterol and fatty acid metabolism. Studies of the genetic and biochemical properties of primate CES may contribute to an improved understanding of human disease, including atherosclerosis, obesity and drug addiction, for which non-human primates serve as useful animal models.
Methods  We cloned and sequenced baboon CES1 and CES2 and used in vitro and in silico methods to predict protein secondary and tertiary structures, and examined evolutionary relationships for these enzymes with other primate and mouse CES orthologs.
Results and Conclusions  We found that baboon CES1 and CES2 proteins retained extensive similarity with human CES1 and CES2, shared key structural features reported for human CES1, and showed family specific sequences consistent with their multimeric and monomeric subunit structures respectively.  相似文献   
963.
We present a detailed method for constructing a vector system composed of plasmids encoding immunoglobulin genes that have been constructed in such a fashion so as to allow for the generation and secretion of antibodies of multiple specificities and isotypes via a rapid and easy cloning-and-ligation scheme. Restriction sites within each plasmid allow for the removal of variable domains, constant domains, leader sequences, or the entire immunoglobulin gene. Degenerate primers are used to clone variable regions from hybridoma cDNAs, allowing for the creation of antibodies with varying binding specificities. Sequence-specific primers are used to clone antibody constant domains, allowing for the creation of antibodies of multiple isotypes from a variety of lineages. A high-efficiency leader sequence has been inserted into the start of each gene to improve secretion. Antibodies constructed through this system are efficiently secreted by transfected cells, and are fully functional in antigen-specific binding assays.  相似文献   
964.
Aims: The aim of the present work was to characterize the heterotrophic bacterial community of a marine recirculating aquaculture system (RAS). Methods and Results: An experimental RAS was sampled for the rearing water (RW) and inside the biofilter. Samples were analysed for bacterial abundances, community structure and composition by using a combination of culture‐dependent and ‐independent techniques. The most represented species detected among biofilter clones was Pseudomonas stutzeri, while Ruegeria spp. and Roseobacter spp. were more abundant among isolates. In comparison, the genera Roseobacter and Ruegeria were well represented in both the biofilter and the RW samples. A variety of possible bacterial pathogens (e.g. Vibrio spp., Erwinia spp. and Coxiella spp.) were also identified in this study. Conclusions: Results revealed that the bacterial community in the RW was quite different to that associated with the biofilter. Moreover, data obtained suggest that the whole bacterial community can be involved in maintaining an effective and a stable rearing environment (shelter effect). Significance and Impact of the Study: Improving the reliability and the sustainability of RAS depends on the correct management of the bacterial populations inside it. This study furnishes more accurate information on the bacterial populations and better clarifies the existing relationships between the bacterial flora in the RW and that associated with the biofilter.  相似文献   
965.
966.
In this study, a cDNA encoding cyclophilin (CyP) of Gnathostoma spinigerum was cloned into a prokaryotic expression vector and expressed in Escherichia coli. The predicted molecular mass of the putative protein was 18.6 kDa, and the deduced amino acid sequence had 86, 84.8, 81.3 and 77.2% identity with the CyP of Dirofilaria immitis, Brugia malayi, Onchocerca volvulus and Caenorhabditis elegans, respectively. A prediction of linear B-cell epitopes with high hydrophilicity and immunoblotting results indicated that the recombinant CyP has antigenicity to humans. The recombinant CyP protein reacted with human gnathostomiasis sera but not with other parasitosis or healthy control sera, suggesting that it might be useful for the serodiagnosis of human gnathostomiasis.  相似文献   
967.
A d ‐mannose specific lectin was purified from the green marine alga, Bryopsis plumosa (Huds.) Ag. The lectin agglutinated horse and sheep erythrocytes. Matrix assisted laser desorption/ionization time of flight mass spectrometry, size exclusion chromatography, sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and two dimensional gel electrophoresis (2DE) results showed that the lectin was a monomer with molecular weight of 17 kDa and pI 7.3. The agglutinating activity was inhibited by d ‐mannose (1 mM), α‐methyl‐D‐mannose (4 mM) and l ‐fucose (8 mM). d ‐glucose (125 mM) showed weak inhibition. The lectin did not need divalent cations for agglutinating activity. N‐terminal amino acid sequence of the lectin was analyzed. As the lectin was novel, we named it BPL‐2 (Bryopsis plumosa lectin 2). Full cDNA sequence of BPL‐2 was obtained using cDNA library. It was comprised of 624 bp of open reading frame and 167 bp/57 bp of 3′/5′ untranslated regions as well as N‐terminal signal peptide. No antimicrobial activity of BPL‐2 was observed in four bacteria strains tested.  相似文献   
968.
This study describes the identification and structural characterization of Sus scrofa statherin. HPLC–electrospray ionization mass spectrometry analysis on pig parotid secretory granule extracts evidenced a peptide with a molecular mass value of 5381.1 ± 0.6 Da and its truncated form, devoid of the C‐terminal Ala residue, with a molecular mass value of 5310.1 ± 0.6 Da. The complete sequence of pig statherin gene was determined by sequencing the full‐length cDNA obtained by rapid amplification of cDNA ends. The gene is 549 base pairs long and contains an open reading frame of 185 nucleotides, encoding a 42‐amino acid secretory polypeptide with a signal peptide of 19 residues. This sequence presents some typical features of the four statherins characterized till now, showing the highest degree of amino acid identity with bovine (57%) and human statherin (39%). Pig statherin is mono‐phoshorylated on Ser‐3, while primate statherins already characterized are di‐phosphorylated on Ser‐2 and Ser‐3. This difference, probably connected to the Asp‐4 → Glu substitution, suggests the involvement of the Golgi‐casein kinase, which strictly recognizes the SX(E/pS) consensus sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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970.
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