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21.
22.
Ahmed S Abdel-Moneim Ahmad E Abdel-Ghany Salama AS Shany 《Journal of biomedical science》2010,17(1):25
Background
The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. 相似文献23.
Acute myeloid leukemia (AML) is a malignant blood disease caused by different mutations that enhance the pro-liferative activity
and survival of blood cells and affect their differentiation and apoptosis. The most frequent disorders in AML are translocations
between chromosomes 21 and 8 leading to production of a chimeric oncogene, AML1-ETO, and hyperexpression of the receptor tyrosine kinase KIT. Mutations in these genes often occur jointly. The presence in cells
of two activated oncogenes is likely to trigger their malignization. The current approaches for treatment of oncologic diseases
(bone marrow transplantation, radiotherapy, and chemotherapy) have significant shortcomings, and thus many laboratories are
intensively developing new approaches against leukemias. Inhibiting expression of activated leukemic oncogenes based on the
principle of RNA interference seems to be a promising approach in this field. 相似文献
24.
A. S. Spirin 《Paleontological Journal》2010,44(7):737-746
Based on the modern concept of multiplicity of RNA functions, certain new mechanisms, which could have played a key role in
the origin and evolution of the ancient RNA world, are discussed. In particular, the reaction of spontaneous transesterification
of polyribonucleotides, which was discovered by A.B. Chetverin and colleagues, could result in elongation of short initial
oligoribonucleotides and produce sequence variants for further natural selection of accidentally arising functionally active
molecules. Further, the formation of mixed molecular colonies of RNA on moist solid media, such as clays, could have provided
compartmentation of functional RNA ensembles in the absence of envelopes or membranes, which were necessary for further evolution
of the RNA world. The systematic exponential enrichment of the RNA population with functionally the best molecules because
of alternating dissolution of colonies due to flooding and formation of new colonies due to drying in ancient pools (“primordial
natural SELEX”) could be critical for the evolutionary process in the RNA world. 相似文献
25.
Jessica AB van Nies Rute B Marques Stella Trompet Zuzana de Jong Fina AS Kurreeman Rene EM Toes J Wouter Jukema Tom WJ Huizinga Annette HM van der Helm-van Mil 《Arthritis research & therapy》2010,12(2):R38
Introduction
Recently an association between a genetic variation in TRAF1/C5 and mortality from sepsis or cancer was found in rheumatoid arthritis (RA). The most prevalent cause of death, cardiovascular disease, may have been missed in that study, since patients were enrolled at an advanced disease stage. Therefore, we used an inception cohort of RA patients to investigate the association between TRAF1/C5 and cardiovascular mortality, and replicate the findings on all-cause mortality. As TRAF1/C5 associated mortality may not be restricted to RA, we also studied a large cohort of non-RA patients. 相似文献26.
The database NPIDB (Nucleic Acids-Protein Interaction DataBase) contains information derived from structures of DNA-protein and RNA-protein complexes extracted from PDB (1834 complexes in July 2007). It is organized as a collection of files in PDB format and is equipped with a web-interface and a set of tools for extracting biologically meaningful characteristics of complexes. The content of the database is weekly updated. AVAILABILITY: http://monkey.belozersky.msu.ru/NPIDB/ 相似文献
27.
Background
There have been many algorithms and software programs implemented for the inference of multiple sequence alignments of protein and DNA sequences. The "true" alignment is usually unknown due to the incomplete knowledge of the evolutionary history of the sequences, making it difficult to gauge the relative accuracy of the programs. 相似文献28.
On single and multiple models of protein families for the detection of remote sequence relationships
Background
The detection of relationships between a protein sequence of unknown function and a sequence whose function has been characterised enables the transfer of functional annotation. However in many cases these relationships can not be identified easily from direct comparison of the two sequences. Methods which compare sequence profiles have been shown to improve the detection of these remote sequence relationships. However, the best method for building a profile of a known set of sequences has not been established. Here we examine how the type of profile built affects its performance, both in detecting remote homologs and in the resulting alignment accuracy. In particular, we consider whether it is better to model a protein superfamily using a single structure-based alignment that is representative of all known cases of the superfamily, or to use multiple sequence-based profiles each representing an individual member of the superfamily. 相似文献29.
Background
Trichomonosis caused by Trichomonas vaginalis is the number one, non-viral sexually transmitted disease (STD) that affects more than 250 million people worldwide. Immunoglobulin A (IgA) has been implicated in resistance to mucosal infections by pathogens. No reports are available of IgA-reactive proteins and the role, if any, of this class of antibody in the control of this STD. The availability of an IgA monoclonal antibody (mAb) immunoreactive to trichomonads by whole cell (WC)-ELISA prompted us to characterize the IgA-reactive protein of T. vaginalis. 相似文献30.
Anna S. Ershova Anna S. Karyagina Mikhail O. Vasiliev Alexander M. Lyashchuk Vladimir G. Lunin Sergey A. Spirin Andrei V. Alexeevski 《Nucleic acids research》2012,40(20):10107-10115
Prokaryotic restriction-modification (R-M) systems defend the host cell from the invasion of a foreign DNA. They comprise two enzymatic activities: specific DNA cleavage activity and DNA methylation activity preventing cleavage. Typically, these activities are provided by two separate enzymes: a DNA methyltransferase (MTase) and a restriction endonuclease (RE). In the absence of a corresponding MTase, an RE of Type II R-M system is highly toxic for the cell. Genes of the R-M system are linked in the genome in the vast majority of annotated cases. There are only a few reported cases in which the genes of MTase and RE from one R-M system are not linked. Nevertheless, a few hundreds solitary RE genes are present in the Restriction Enzyme Database (http://rebase.neb.com) annotations. Using the comparative genomic approach, we analysed 272 solitary RE genes. For 57 solitary RE genes we predicted corresponding MTase genes located distantly in a genome. Of the 272 solitary RE genes, 99 are likely to be fragments of RE genes. Various explanations for the existence of the remaining 116 solitary RE genes are also discussed. 相似文献