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951.
952.
Proteomic analysis of the mouse liver mitochondrial inner membrane 总被引:14,自引:0,他引:14
Da Cruz S Xenarios I Langridge J Vilbois F Parone PA Martinou JC 《The Journal of biological chemistry》2003,278(42):41566-41571
Mitochondria play a crucial role in cellular homeostasis, which justifies the increasing interest in mapping the different components of these organelles. Here we have focused our study on the identification of proteins of the mitochondrial inner membrane (MIM). This membrane is of particular interest because, besides the well known components of the respiratory chain complexes, it contains several ion channels and many carrier proteins that certainly play a key role in mitochondrial function and, therefore, deserve to be identified at the molecular level. To achieve this goal we have used a novel approach combining the use of highly purified mouse liver mitochondrial inner membranes, extraction of membrane proteins with organic acid, and two-dimensional liquid chromatography coupled to tandem mass spectrometry. This procedure allowed us to identify 182 proteins that are involved in several biochemical processes, such as the electron transport machinery, the protein import machinery, protein synthesis, lipid metabolism, and ion or substrate transport. The full range of isoelectric point (3.9-12.5), molecular mass (6-527 kDa), and hydrophobicity values (up to 16 transmembrane predicted domains) were represented. In addition, of the 182 proteins found, 20 were unknown or had never previously been associated with the MIM. Overexpression of some of these proteins in mammalian cells confirmed their mitochondrial localization and resulted in severe remodeling of the mitochondrial network. This study provides the first proteome of the MIM and provides a basis for a more detailed study of the newly characterized proteins of this membrane. 相似文献
953.
Aidinis V Plows D Haralambous S Armaka M Papadopoulos P Kanaki MZ Koczan D Thiesen HJ Kollias G 《Arthritis research & therapy》2003,5(3):R140-R157
Increasing attention has been directed towards identifying non-T-cell mechanisms as potential therapeutic targets in rheumatoid
arthritis. Synovial fibroblast (SF) activation, a hallmark of rheumatoid arthritis, results in inappropriate production of
chemokines and matrix components, which in turn lead to bone and cartilage destruction. We have demonstrated that SFs have
an autonomous pathogenic role in the development of the disease, by showing that they have the capacity to migrate throughout
the body and cause pathology specifically to the joints. In order to decipher the pathogenic mechanisms that govern SF activation
and pathogenic potential, we used the two most prominent methods of differential gene expression analysis, differential display
and DNA microarrays, in a search for deregulated cellular pathways in the arthritogenic SF. Functional clustering of differentially
expressed genes, validated by dedicated in vitro functional assays, implicated a number of cellular pathways in SF activation. Among them, diminished adhesion to the extracellullar
matrix was shown to correlate with increased proliferation and migration to this matrix. Our findings support an aggressive
role for the SF in the development of the disease and reinforce the perspective of a transformed-like character of the SF. 相似文献
954.
Chakrabarti D Da Silva T Barger J Paquette S Patel H Patterson S Allen CM 《The Journal of biological chemistry》2002,277(44):42066-42073
Comparison of the malaria parasite and mammalian protein prenyltransferases and their cellular substrates is important for establishing this enzyme as a target for developing antimalarial agents. Nineteen heptapeptides differing only in their carboxyl-terminal amino acid were tested as alternative substrates of partially purified Plasmodium falciparum protein farnesyltransferase. Only NRSCAIM and NRSCAIQ serve as substrates, with NRSCAIM being the best. Peptidomimetics, FTI-276 and GGTI-287, inhibit the transferase with IC(50) values of 1 and 32 nm, respectively. Incubation of P. falciparum-infected erythrocytes with [(3)H]farnesol labels 50- and 22-28-kDa proteins, whereas [(3)H]geranylgeraniol labels only 22-28-kDa proteins. The 50-kDa protein is shown to be farnesylated, whereas the 22-28-kDa proteins are geranylgeranylated, irrespective of the labeling prenol. Protein labeling is inhibited more than 50% by either 5 microm FTI-277 or GGTI-298. The same concentration of inhibitors also inhibits parasite growth from the ring stage by 50%, decreases expression of prenylated proteins as measured with prenyl-specific antibody, and inhibits parasite differentiation beyond the trophozoite stage. Furthermore, differentiation specific prenylation of P. falciparum proteins is demonstrated. Protein labeling is detected predominantly during the trophozoite to schizont and schizont to ring transitions. These results demonstrate unique properties of protein prenylation in P. falciparum: a limited specificity of the farnesyltransferase for peptide substrates compared with mammalian enzymes, the ability to use farnesol to label both farnesyl and geranylgeranyl moieties on proteins, differentiation specific protein prenylation, and the ability of peptidomimetic prenyltransferase inhibitors to block parasite differentiation. 相似文献
955.
956.
957.
A novel method of photodynamic diagnosis of cancer mediated by chemiluminescence probe is presented. The mechanism for photodynamic therapy involves singlet oxygen ((1)O(2)) generated by energy transfer from photosensitizers. (1)O(2) can react with 3,7-dihydro-6-[4-[2-(N'-(5-fluoresceinyl)thioureido)ethoxy]phenyl]-2-methylimidazo[1,2-a]pyrazin-3-one sodium salt (FCLA), which is a Cypridina luciferin analog and a specific chemiluminescence probe for detecting (1)O(2) and superoxide (O(2)(-)). The reaction of FCLA and (1)O(2) can give emission with peak wavelength at about 532 nm. In the present study, FCLA was chosen as an optical reporter of (1)O(2) produced from the photosensitization reaction of hematoporphyrin derivative in model solution and in nude mice with transplanted mammary cancer. Photosensitized chemiluminescence from the reaction of FCLA with (1)O(2) was detected by a highly sensitive Intensified Charge-Coupled Device detector. The chemiluminescence was markedly inhibited by the addition of 10 mmol/l sodium azide (NaN(3)) to the model solution and minor effects were observed at the addition of 10 micromol/l superoxide dismutase, 20 mmol/l mannitol and 100 microg/ml catalase, respectively, thus indicating that (1)O(2) generation from photosensitization reaction mainly results in light emission. Experiments in vivo with tumor-bearing mice showed a clear chemiluminescence image of tumor. The study suggests that this novel method may be applicable to the diagnosis of superficial tumors. 相似文献
958.
Stejskal D Prosková J Adamovská S Juráková R Bartek J 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2002,146(2):47-49
Resistin is a signal peptide produced by adipose tissue. Mice models have confirmed that resistin may play an important role in insulin resistance. Its function in the human organism has not been elucidated yet. Since in common population the resistin concentrations are not known (no validated commercial set is available), we performed resistin assessment using the ELISA method (with satisfying analytical characteristics) in a population of 123 non-obese probands without signs of insulin resistance and/or inflammation. Mean resistin values amounted to 14.3 ng/ml (reference limit of 7.3-21.3 ng/ml). 相似文献
959.
Matos M.C. Matos A.A. Mantas A. Cordeiro V. Vieira Da Silva J.B. 《Photosynthetica》1998,34(2):249-256
Five cultivars of Prunus amygdalus Batsch (Ferragnes, Ferrastar, Marcona, Garrigues, and Non Pareil) grafted on two different rootstocks (Garrigues and GF677), and two cultivars (Ferraduel and Casa Nova) grafted on GF677, were grown for three years under rainfed conditions in an orchard in northeast Portugal. Net photosynthetic rate (PN), leaf conductance for water vapour (gs), leaf water potential (Ψ), instantaneous water use efficiency (WUE), and internal CO2 concentration (Ci) were measured at three periods of the growing season: spring, summer (June or July) and late summer (September) over two years. Ferraduel, Ferrastar, and Marcona presented the best performance in the periods when environmental conditions were not very hard (May or September). Casa Nova and Non Pareil were well adapted to high air evaporative demand, preventing the increase of leaf temperature (T1). Ferrastar, although having a good performance in May and September, did well adapt to hard climatic conditions in June 1994. In the following year, although it presented the highest T1, the values were not limiting (30.6 ± 2.1 °C), and PN was only decreased from May to July. Marcona was highly dependent on T1, but prevented its increasing. Garrigues showed lower PN in most measurement periods. GF677 frequently induced the highest PN, WUE, and Ψ. PN was mainly dependent on T1, radiation, Ci, month, and year. WUE depended on the same factors. Ψ depended mainly on gs, air temperature, month, and year. 相似文献
960.
An autoselection system for increasing plasmid stability in Kluyveromyces lactis, based on the blockage of the pyrimidine de novo and salvage pathways, was investigated. In a manner analogous to that used in Saccharomyces cerevisiae, a putative “fur1” mutation was selected in a uraA K. lactis strain using 5-fluorouracil and 5-fluorocytosine plates. Survival of the mutant required expression of a plasmid-borne URA3 gene regardless of the culture medium employed, verifying the efficacy of this autoselection system in K. lactis. The expression of heterologous invertase, encoded by the S. cerevisiae SUC2 gene, was studied during long-term sequential batch cultures (70 generations) in complex yeast/peptone/glucose medium. The
fur1 mutant successfully retained the plasmid; invertase specific activity remained above 90% of the initial level. Furthermore,
no mutation reversion was observed. In contrast, for the control non-fur1 strain, only 4% of the cells retained the plasmid after 70 generations, and invertase specific activity dropped to less than
10% of the initial level. Experiments comparing growth and activity in different media indicated the potential for improving
productivity through medium enrichment using this autoselection system.
Received: 1 April 1997 / Received revision: 16 August 1997 / Accepted: 11 September 1997 相似文献