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21.
Marcia Puchi Jenaro García‐Huidobro Candy Cordova Rodrigo Aguilar Estefanie Dufey Maria Imschenetzky Paula Bustos Violeta Morin 《Journal of cellular biochemistry》2010,111(5):1099-1106
Recently many authors have reported that cathepsin L can be found in the nucleus of mammalian cells with important functions in cell‐cycle progression. In previous research, we have demonstrated that a cysteine protease (SpH‐protease) participates in male chromatin remodeling and in cell‐cycle progression in sea urchins embryos. The gene that encodes this protease was cloned. It presents a high identity sequence with cathepsin L family. The active form associated to chromatin has a molecular weight of 60 kDa, which is higher than the active form of cathepsin L described until now, which range between 25 and 35 kDa. Another difference is that the zymogen present in sea urchin has a molecular weight of 75 and 90 kDa whereas for human procathepsin L has a molecular weight of 38–42 kDa. Based on these results and using a polyclonal antibody available in our laboratory that recognizes the active form of the 60 kDa nuclear cysteine protease of sea urchin, ortholog to human cathepsin L, we investigated the presence of this enzyme in HeLa and Caco‐2 cells. We have identified a new nuclear protease, type cathepsin L, with a molecular size of 60 kDa, whose cathepsin activity increases after a partial purification by FPLC and degrade in vitro histone H1. This protease associates to the mitotic spindle during mitosis, remains in the nuclei in binuclear cells and also translocates to the cytoplasm in non‐proliferative cells. J. Cell. Biochem. 111: 1099–1106, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
22.
Carlos Bustos Desmond Mac-Leod Carey René Thouvenot Pierre Gouzerh 《Inorganica chimica acta》2010,363(15):4262-4268
A series of aryldiazenido polyoxomolybdates of the type (nBu4N)2[Mo5O13(OMe)4(NNAr){Na(MeOH)}] (Ar = C6F5, 1; Ar = O2N-o-C6H4, 2; Ar = O2N-m-C6H4, 3; Ar = O2N-p-C6H4, 4a; Ar = (O2N)2-o,p-C6H3, 5) have been obtained by controlled degradation of the parent compounds (nBu4N)3[Mo6O18(NNAr)] with NaOH in methanol. They have been characterized by elemental analysis and UV-Vis and IR spectroscopy. In addition, 4a has been characterized by 95Mo NMR spectroscopy and the crystal structure of (nBu4N)2[Mo5O13(OMe)4(NNC6H4-p-NO2){Na(H2O))]·H2O (4b) has been determined by X-ray diffraction. The molecular structure of the anion of 4b features a lacunary Lindqvist-type anion [Mo5O13(OMe)4(NNC6H4-p-NO2)]3− interacting with a sodium cation through the four terminal axial oxygen atoms. The 1:1 sodium complexes react with BaCl2 and BiCl3 to yield 2:1 complexes which have been isolated as (nBu4N)4[Ba{Mo5O13(OMe)4(NNAr)}2] (Ar = C6F5, 6; Ar = O2N-p-C6H4, 7) and (nBu4N)3[Bi{Mo5O13(OMe)4(NNAr)}2] (Ar = C6F5, 8; Ar = O2N-p-C6H4, 9). X-ray crystallography analysis of 9·Me2CO has shown that the tetradentate [Mo5O13(OMe)4(N2C6H4-p-NO2)]3− anions provide a square-antiprismatic environment for Bi. In contrast, IR spectroscopy provides evidence for a square-prismatic environment of Ba in 6 and 7. In acetonitrile-methanol mixed solvent, [Mo5O13(OMe)4(NNAr)]3− and [PW11O39]7−, generated in situ by alkaline degradation of their respective parents, [Mo6O18(NNAr)]3− and [PW12O40]3−, react together to give the Keggin-type diazenido compounds (nBu4N)4[PW11O39(MoNNAr)] (Ar = O2N-o-C6H4, 10; Ar = O2N-m-C6H4, 11; Ar = O2N-p-C6H4, 12), which have been characterized by 31P and 183W NMR spectroscopy. 相似文献
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24.
Anion exchanger 1 (AE1, Band 3) is the predominant membrane protein of erythrocytes. Its 52 kDa C-terminal domain functions as a chloride-bicarbonate exchanger, while its 43 kDa N-terminal cytosolic domain (cdb3) anchors the cytoskeleton to the membrane. Several proteins bind to cdb3, including protein 4.2, a cytoskeletal protein. Three mutations in cdb3 are associated with hereditary spherocytosis (HS) and decreased levels of protein 4.2 in erythrocytes. In this study, these cdb3 mutants (E40K, G130R, and P327R) were expressed in and purified from Escherichia coli. Sedimentation experiments showed that the wild-type and mutant proteins are dimers. No difference in secondary structure between mutant and wild-type proteins was detected using circular dichroism (CD) analysis. The wild-type and mutant proteins underwent similar pH-dependent conformational changes when monitored by intrinsic tryptophan fluorescence. Urea denaturation of proteins monitored by intrinsic fluorescence showed no significant differences in the sensitivity of the proteins to this chemical denaturant. Thermal denaturation monitored by CD and by calorimetry revealed that only the P327R mutant had a significantly lower midpoint of transition (approximately 5 degrees C) than the wild-type protein, suggesting a modest decrease in stability. The results show that the HS mutant cdb3 proteins do not differ to any great extent in structure from the wild-type protein, suggesting that the HS mutations may directly affect protein 4.2 binding. 相似文献
25.
Cueva C Mingo S Muñoz-González I Bustos I Requena T del Campo R Martín-Álvarez PJ Bartolomé B Moreno-Arribas MV 《Letters in applied microbiology》2012,54(6):557-563
Aims: To investigate the effect of seven wine phenolic compounds and six oenological phenolic extracts on the growth of pathogenic bacteria associated with respiratory diseases (Pseudomonas aeruginosa, Staphylococcus aureus, Moraxella catarrhalis, Enterococcus faecalis, Streptococcus sp Group F, Streptococcus agalactiae and Streptococcus pneumoniae). Methods and Results: Antimicrobial activity was determined using a microdilution method and quantified as IC50. Mor. catarrhalis was the most susceptible specie to phenolic compounds and extracts. Gallic acid and ethyl gallate were the compounds that showed the greatest antimicrobial activity. Regarding phenolic extracts, GSE (grape seed extract) and GSE‐O (oligomeric‐rich fraction from GSE) were the ones that displayed the strongest antimicrobial effects. Conclusions: Results highlight the antimicrobial properties of wine phenolic compounds and oenological extracts against potential respiratory pathogens. The antimicrobial activity of wine phenolic compounds was influenced by the type of phenolic compounds. Gram‐negative bacteria were more susceptible than Gram‐positive bacteria to the action of phenolic compounds and extracts; however, the effect was species‐dependent. Significance and Impact of Study: The ability to inhibit the growth of respiratory pathogenic bacteria as shown by several wine phenolic compounds and oenological extracts warrants further investigations to explore the use of grape and wine preparations in oral hygiene. 相似文献
26.
Olmo ED Diaz-González R Escarcena R Carvalho L Bustos LA Navarro M Feliciano AS 《Bioorganic & medicinal chemistry letters》2012,22(1):440-443
Twenty compounds selected as representative members of three series of long-chain 1,2-diamines, 2-amino-1-alkanols and 1-amino-2-alkanols structurally related to dihydrosphingosin, were synthesized and tested in vitro for their ability to inhibit the sleeping sickness parasites Trypanosoma bruceirhodesiense and Trypanosoma brucei gambiense. Eight compounds showed EC(50) values in the submicromolar range, with selectivity indexes up to 39 related to the respective cytotoxicity values for Vero cells. The parasite phenotype detected after treatment with the most potent compounds showed irreversible cell morphology alterations of the flagellar pocket that lead to inhibition of cell growth and parasite death. 相似文献
27.
Morin V Sanchez A Quiñones K Huidobro JG Iribarren C Bustos P Puchi M Genevière AM Imschenetzky M 《Journal of cellular physiology》2008,216(3):790-795
We have previously reported that sperm histones (SpH) degradation after fertilization is catalyzed by a cystein-protease (SpH-protease). Its inhibition blocks the degradation of SpH in vivo and also aborts sea urchin development at the initial embryonic cell cycles. It remains unknown if this effect is a consequence of the persistence of SpH on zygotic chromatin, or if this protease is involved per-se in the progression of the embryonic cell cycles. To discriminate among these two options we have inhibited this protease at a time when male chromatin remodeling was completed and the embryos were engaged in the second cell cycle of the cleavage divisions. The role of this enzyme in cell cycle was initially analyzed by immuno-inhibiting its SpH degrading activity in one of the two blastomeres after the initial cleavage division, while the other blastomere was used as a control. We found that in the blastomere injected with the anti-SpH-protease antibodies the cytokinesis was arrested, the chromatin failed to decondense after mitosis and BrdU incorporation into DNA was blocked. Since the N-terminal sequence and the SpH protease was homologous to the cathepsin L (Cat L) family of proteases, we subsequently investigated if the deleterious effect of the inhibition of this protease is related to its Cat L activity. In this context we analyzed the effect of Cat L inhibitor I (Z-Phe-Phe-CH(2)F) on embryonic development. We found that the addition of 100 uM of this inhibitor to the embryos harvested at the time of the initial cleavage division (80 min p.i.) mimics perfectly the effects of the immuno-inhibition of this enzyme obtained by microinjecting the anti-SpH-protease antibodies. Taken together these results indicate that the activity of this protease is required for embryonic cell cycle progression. Interestingly, we observed that when this protease was inhibited the chromatin decondensation after mitosis was abolished indicating that the inhibition of this enzyme affects chromosomes decondensation after mitosis. 相似文献
28.
M. C. J. Bottini A. De Bustos N. Jouve L. Poggio 《Plant Systematics and Evolution》2002,231(1-4):133-142
AFLP markers were used to analyse the intra- and interspecific relationships among 22 natural populations of 13 Patagonian
species of Berberis and the relationships among the taxa belonging to homoploid and polyploid complexes. Seven primer combinations gave rise
to 231 AFLP bands, of which 199 were polymorphic. Correspondence between AFLP data, morphological traits and seed protein
bands was also assessed. The dendrogram inferred from AFLP fingerprints showed that, in general, populations of the same species
formed closely related groups with high coefficients of similarity. Principal co-ordinates analysis showed two separate subgroups:
(i) B. bidentata and their putative ancestors –B. darwinii and B. linearifolia– which form a homogamic group, and (ii) B. buxifolia, B. heterophylla and B. parodii– which could form a polyploid hybrid complex.
Received March 21, 2001 Accepted September 11, 2001 相似文献
29.
Jerri Caldeira Jeremiah Bustos Julianne Peabody Bryce Chackerian David S. Peabody 《PloS one》2015,10(10)
The possibility of a contraceptive vaccine targeting human chorionic gonadotropin has long been recognized, but never fully realized. Here we describe an epitope-specific approach based on immunogenic display of hCG-derived peptides on virus-like particles of RNA bacteriophage. A number of recombinant VLPs were constructed, each displaying a different hCG-derived peptide. Some were taken from the disordered C-terminal tail of the hormone, another came from an internal loop, and yet another was an epitope mimic produced by affinity-selection on an hCG-neutralizing antibody target. Immunization of mice with some VLPs yielded antisera that bound the hormone and neutralized hCG biological activity. 相似文献
30.