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991.
Roland Schwarz Chunguang Liang Christoph Kaleta Mark Kühnel Eik Hoffmann Sergei Kuznetsov Michael Hecker Gareth Griffiths Stefan Schuster Thomas Dandekar 《BMC bioinformatics》2007,8(1):313
Background
Modeling of metabolic networks includes tasks such as network assembly, network overview, calculation of metabolic fluxes and testing the robustness of the network. 相似文献992.
Localization of vacuolar transport receptors and cargo proteins in the Golgi apparatus of developing Arabidopsis embryos 总被引:5,自引:1,他引:4
Hinz G Colanesi S Hillmer S Rogers JC Robinson DG 《Traffic (Copenhagen, Denmark)》2007,8(10):1452-1464
Using immunogold electron microscopy, we have investigated the relative distribution of two types of vacuolar sorting receptors (VSR) and two different types of lumenal cargo proteins, which are potential ligands for these receptors in the secretory pathway of developing Arabidopsis embryos. Interestingly, both cargo proteins are deposited in the protein storage vacuole, which is the only vacuole present during the bent-cotyledon stage of embryo development. Cruciferin and aleurain do not share the same pattern of distribution in the Golgi apparatus. Cruciferin is mainly detected in the cis and medial cisternae, especially at the rims where storage proteins aggregate into dense vesicles (DVs). Aleurain is found throughout the Golgi stack, particularly in the trans cisternae and trans Golgi network where clathrin-coated vesicles (CCVs) are formed. Nevertheless, aleurain was detected in both DV and CCV. VSR-At1, a VSR that recognizes N-terminal vacuolar sorting determinants (VSDs) of the NPIR type, localizes mainly to the trans Golgi and is hardly detectable in DV. Receptor homology-transmembrane-RING H2 domain (RMR), a VSR that recognizes C-terminal VSDs, has a distribution that is very similar to that of cruciferin and is found in DV. Our results do not support a role for VSR-At1 in storage protein sorting, instead RMR proteins because of their distribution similar to that of cruciferin in the Golgi apparatus and their presence in DV are more likely candidates. Aleurain, which has an NPIR motif and seems to be primarily sorted via VSR-At1 into CCV, also possesses putative hydrophobic sorting determinants at its C-terminus that could allow the additional incorporation of this protein into DV. 相似文献
993.
994.
The complete nucleotide sequence of the cucumber (C. sativus L. var. Borszczagowski) chloroplast genome has been determined. The genome is composed of 155,293 bp containing a pair of
inverted repeats of 25,191 bp, which are separated by two single-copy regions, a small 18,222-bp one and a large 86,688-bp
one. The chloroplast genome of cucumber contains 130 known genes, including 89 protein-coding genes, 8 ribosomal RNA genes
(4 rRNA species), and 37 tRNA genes (30 tRNA species), with 18 of them located in the inverted repeat region. Of these genes,
16 contain one intron, and two genes and one ycf contain 2 introns. Twenty-one small inversions that form stem-loop structures, ranging from 18 to 49 bp, have been identified.
Eight of them show similarity to those of other species, while eight seem to be cucumber specific. Detailed comparisons of
ycf2 and ycf15, and the overall structure to other chloroplast genomes were performed. 相似文献
995.
Michael Hust Thomas Jostock Christian Menzel Bernd Voedisch Anja Mohr Mariam Brenneis Martina I Kirsch Doris Meier Stefan Dübel 《BMC biotechnology》2007,7(1):14
Background
The connection of the variable part of the heavy chain (VH) and and the variable part of the light chain (VL) by a peptide linker to form a consecutive polypeptide chain (single chain antibody, scFv) was a breakthrough for the functional production of antibody fragments in Escherichia coli. Being double the size of fragment variable (Fv) fragments and requiring assembly of two independent polypeptide chains, functional Fab fragments are usually produced with significantly lower yields in E. coli. An antibody design combining stability and assay compatibility of the fragment antigen binding (Fab) with high level bacterial expression of single chain Fv fragments would be desirable. The desired antibody fragment should be both suitable for expression as soluble antibody in E. coli and antibody phage display. 相似文献996.
Expanding research in the field of modified oligonucleotides demands suitable analytical tools for size and purity verification of known compounds and accurate structure elucidation of unknowns. There is a need for characterization of the types and sites of modifications in oligonucleotides and to identify and sequence selected candidates originating from synthesis. The potential of electrospray tandem mass spectrometry (ESI-MS/MS) for structural characterization and sequencing of oligonucleotides is demonstrated. The fundamental behavior of DNA, RNA, and selected modified oligonucleotides in gas-phase is shown. Since gas-phase dissociation does not demand specific structural prerequisites, the method bears a great potential for rapid and most accurate characterization of modified oligonucleotides, e.g. from combinatorial libraries. 相似文献
997.
998.
999.
Haas J Mueller-Kuller T Klein S Engels JW 《Nucleosides, nucleotides & nucleic acids》2007,26(6-7):865-868
We recently reported that a 1'-deoxy-1'-(4,6-difluoro-1H-benzimidazol-1-yl)-2'-(beta-aminoethyl)-beta-d-ribofuranose nucleoside appears to be a universal nucleoside which does not differentiate between the four natural nucleosides A, C, G, and U in duplexes. Moreover, ribozymes modified with this nucleoside analog showed a better or at least equal catalytic activity relative to Watson-Crick mismatches.[1] Due to these data, we investigated the ability of this compound to tolerate Watson-Crick mismatches in order to avoid HIV escape mutations in RNA interference. The influence of this nucleoside analog on siRNA efficiency was analyzed with a proven siRNA targeting GFP. 相似文献
1000.
A new fast method for identification and characterization of proteolytic digests of proteins by monolithic liquid chromatography coupled with mass spectrometry has been developed. The advantages of the monolithic columns are a high-pressure stability and low back pressure resulting in higher flow rates for capillary or nanosize columns simplifying the system handling. As was shown in several publications, such monolithic stationary phases are highly qualified for the analysis of peptides and proteins, but so far, only small volumes could be injected into the system, which might hamper the sample preparation leading to protein precipitation and partial loss of sample. To overcome the problem of small injection volumes, we established a system including a short monolithic trap column to allow preconcentration of the peptides. The injected sample is flushed at higher flow rates onto the trap column, bound to the stationary phase, and in this way concentrated in a few nanoliters before starting the separation. The expanded system was optimized and tested using different reference protein samples. Eluting peptides were detected by MALDI-TOF/TOF-MS and identified by database searching. The system is now a permanent part for proteome analysis in our lab, and as such, it was successfully applied for the detection of post-translational modifications and the analysis of membrane proteins. One example for these analyses is also included in this paper. 相似文献