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781.
A. Shukla P. Chaurasia S. R. Bhaumik 《Cellular and molecular life sciences : CMLS》2009,66(8):1419-1433
Methylation of lysine residues of histones is associated with functionally distinct regions of chromatin, and, therefore,
is an important epigenetic mark. Over the past few years, several enzymes that catalyze this covalent modification on different
lysine residues of histones have been discovered. Intriguingly, histone lysine methylation has also been shown to be cross-regulated
by histone ubiquitination or the enzymes that catalyze this modification. These covalent modifications and their cross-talks
play important roles in regulation of gene expression, heterochromatin formation, genome stability, and cancer. Thus, there
has been a very rapid progress within past several years towards elucidating the molecular basis of histone lysine methylation
and ubiquitination, and their aberrations in human diseases. Here, we discuss these covalent modifications with their cross-regulation
and roles in controlling gene expression and stability.
Received 24 September 2008; received after revision 21 November 2008; accepted 28 November 2008 相似文献
782.
Berger W Steiner E Grusch M Elbling L Micksche M 《Cellular and molecular life sciences : CMLS》2009,66(1):43-61
The unique and evolutionary highly conserved major vault protein (MVP) is the main component of ubiquitous, large cellular
ribonucleoparticles termed vaults. The 100 kDa MVP represents more than 70% of the vault mass which contains two additional
proteins, the vault poly (ADP-ribose) polymerase (vPARP) and the telomerase-associated protein 1 (TEP1), as well as several
short untranslated RNAs (vRNA). Vaults are almost ubiquitously expressed and, besides chemotherapy resistance, have been implicated
in the regulation of several cellular processes including transport mechanisms, signal transmissions and immune responses.
Despite a growing amount of data from diverse species and systems, the definition of precise vault functions is still highly
complex and challenging. Here we review the current knowledge on MVP and vaults with focus on regulatory functions in intracellular
signal transduction and immune defence.
Received 27 June 2008; received after revision 25 July 2008; accepted 30 July 2008 相似文献
783.
Dirk M. Walther Doron Rapaport Jan Tommassen 《Cellular and molecular life sciences : CMLS》2009,66(17):2789-2804
Membrane-embedded β-barrel proteins span the membrane via multiple amphipathic β-strands arranged in a cylindrical shape.
These proteins are found in the outer membranes of Gram-negative bacteria, mitochondria and chloroplasts. This situation is
thought to reflect the evolutionary origin of mitochondria and chloroplasts from Gram-negative bacterial endosymbionts. β-barrel
proteins fulfil a variety of functions; among them are pore-forming proteins that allow the flux of metabolites across the
membrane by passive diffusion, active transporters of siderophores, enzymes, structural proteins, and proteins that mediate
protein translocation across or insertion into membranes. The biogenesis process of these proteins combines evolutionary conservation
of the central elements with some noticeable differences in signals and machineries. This review summarizes our current knowledge
of the functions and biogenesis of this special family of proteins. 相似文献
784.
Salamah M. Alwahsh Hassan Rashidi David C. Hay 《Cellular and molecular life sciences : CMLS》2018,75(8):1307-1324
The prevalence of liver diseases is increasing globally. Orthotopic liver transplantation is widely used to treat liver disease upon organ failure. The complexity of this procedure and finite numbers of healthy organ donors have prompted research into alternative therapeutic options to treat liver disease. This includes the transplantation of liver cells to promote regeneration. While successful, the routine supply of good quality human liver cells is limited. Therefore, renewable and scalable sources of these cells are sought. Liver progenitor and pluripotent stem cells offer potential cell sources that could be used clinically. This review discusses recent approaches in liver cell transplantation and requirements to improve the process, with the ultimate goal being efficient organ regeneration. We also discuss the potential off-target effects of cell-based therapies, and the advantages and drawbacks of current pre-clinical animal models used to study organ senescence, repopulation and regeneration. 相似文献
785.
Sophie M. Hapak Carla V. Rothlin Sourav Ghosh 《Cellular and molecular life sciences : CMLS》2018,75(15):2735-2761
Polarity is a fundamental feature of cells. Protein complexes, including the PAR3–PAR6–aPKC complex, have conserved roles in establishing polarity across a number of eukaryotic cell types. In neurons, polarity is evident as distinct axonal versus dendritic domains. The PAR3, PAR6, and aPKC proteins also play important roles in neuronal polarization. During this process, either aPKC kinase activity, the assembly of the PAR3–PAR6–aPKC complex or the localization of these proteins is regulated downstream of a number of signaling pathways. In turn, the PAR3, PAR6, and aPKC proteins control various effector molecules to establish neuronal polarity. Herein, we discuss the many signaling mechanisms and effector functions that have been linked to PAR3, PAR6, and aPKC during the establishment of neuronal polarity. 相似文献
786.
787.
788.
Jana Fischer Gunnar Kleinau Claudia Rutz Denise Zwanziger Noushafarin Khajavi Anne Müller Maren Rehders Klaudia Brix Catherine L. Worth Dagmar Führer Heiko Krude Burkhard Wiesner Ralf Schülein Heike Biebermann 《Cellular and molecular life sciences : CMLS》2018,75(12):2227-2239
G-protein-coupled receptors (GPCRs) can constitute complexes with non-GPCR integral membrane proteins, while such interaction has not been demonstrated at a single molecule level so far. We here investigated the potential interaction between the thyrotropin receptor (TSHR) and the monocarboxylate transporter 8 (MCT8), a member of the major facilitator superfamily (MFS), using fluorescence cross-correlation spectroscopy (FCCS). Both the proteins are expressed endogenously on the basolateral plasma membrane of the thyrocytes and are involved in stimulation of thyroid hormone production and release. Indeed, we demonstrate strong interaction between both the proteins which causes a suppressed activation of Gq/11 by TSH-stimulated TSHR. Thus, we provide not only evidence for a novel interaction between the TSHR and MCT8, but could also prove this interaction on a single molecule level. Moreover, this interaction forces biased signaling at the TSHR. These results are of general interest for both the GPCR and the MFS research fields. 相似文献
789.
Cinzia Franchin Christian Borgo Luca Cesaro Silvia Zaramella Jordi Vilardell Mauro Salvi Giorgio Arrigoni Lorenzo A. Pinna 《Cellular and molecular life sciences : CMLS》2018,75(11):2011-2026
CK2 denotes a ubiquitous and pleiotropic protein kinase whose holoenzyme is composed of two catalytic (α and/or α′) and two regulatory β subunits. The CK2 consensus sequence, S/T-x-x-D/E/pS/pT is present in numerous phosphosites, but it is not clear how many of these are really generated by CK2. To gain information about this issue, advantage has been taken of C2C12 cells entirely deprived of both CK2 catalytic subunits by the CRISPR/Cas9 methodology. A comparative SILAC phosphoproteomics analysis reveals that, although about 30% of the quantified phosphosites do conform to the CK2 consensus, only one-third of these are substantially reduced in the CK2α/α′(?/?) cells, consistent with their generation by CK2. A parallel study with C2C12 cells deprived of the regulatory β subunit discloses a role of this subunit in determining CK2 targeting. We also find that phosphosites notoriously generated by CK2 are not fully abrogated in CK2α/α′(?/?) cells, while some phosphosites unrelated to CK2 are significantly altered. Collectively taken our data allow to conclude that the phosphoproteome generated by CK2 is not as ample and rigidly pre-determined as it was believed before. They also show that the lack of CK2 promotes phosphoproteomics perturbations attributable to kinases other than CK2. 相似文献
790.