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981.
D'Andrea Gabriele; Salucci M.Luisa; Pitari Giuseppina; Avigliano Luciana 《Glycobiology》1993,3(6):563-565
Purified ascorbate oxidase from Cucurbita pepo medullosa hasbeen subjected to enzymatic deglycosylation using peptide N-glycosidaseF. Experimental conditions were chosen to obtain efficientlydeglycosylated and active ascorbate oxidase: in particular,three different detergent solutions were added separately tothe incubation mixtures prior to the peptide N-glycosidase F.The detergent solution made of 0.1% (w/v) sodium dodecyl sulphate+ 0.5% (v/v) Nonidet P-40 proved to be the only one effectivefor our purpose. Our results indicate that: (i) the presenceof detergents did not affect the enzymatic activity; (ii) fullydeglycosylated enzyme retained its activity compared with thenative form. Moreover, anti-native ascorbate oxidase antibodiesscarcely recognized deglycosylated protein. ascorbate oxidase blot deglycosylation 相似文献
982.
Marco Scocchi Christine Lüthy Pietro Decarli Giuseppina Mignogna Philipp Christen Renato Gennaro 《International journal of peptide research and therapeutics》2009,15(2):147-155
Bac7, a cathelicidin peptide of the proline-rich group, inactivates bacteria in a stereospecific manner by entering target
cells without any apparent membrane damage and by binding to as yet unknown intracellular targets. The present study was aimed
at detecting these putative intracellular interactors, which might mediate the antibacterial action of this peptide. By using
affinity resins functionalized with the N-terminal 1-35 fragment of Bac7, a single protein was specifically retained with
high affinity from Escherichia coli cytoplasmic protein lysates. This ligand was identified as the heat shock protein DnaK, the Hsp70 homolog in E. coli. The interaction between the peptide and the chaperone is stereospecific, given that a resin prepared with the all-
d enantiomer failed to retain the protein. In vitro, Bac7(1-35) formed a complex with DnaK with an affinity comparable to that
of other known high-affinity peptide ligands. In addition, at 10–100 μM concentration, the peptide inhibited the protein refolding
activity of the complete DnaK/DnaJ/GrpE/ATP molecular chaperone system in a dose-dependent manner. Despite these results,
the in vitro sensitivity to the peptide, under growth permitting conditions, of DnaK-deficient E. coli strains was not significantly affected compared to the wild-type strain. This suggests that, apart from DnaK, other vital
targets for the proline-rich AMPs are present in susceptible bacteria.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Marco Scocchi and Christine Lüthy contributed equally to this work. 相似文献
983.
Mariella Nieddu Roberto Mezzanotte Giuseppina Pichiri Pier Paolo Coni Gian Luca Dedola Maria Luisa Dettori Michele Pazzola Giuseppe Massimo Vacca Renato Robledo 《Genetics and molecular biology》2015,38(4):513-518
Two clones, Bt1 from Bos taurus and Om1 from Ovis orientalis
musimon, were used as probes for hybridization on genomic DNA and on
metaphase chromosomes in members of Bovini and Caprini tribes. Bt1 and Om1 are
sequences respectively belonging to the 1.715 and 1.714 DNA satellite I families.
Southern blots and fluorescence in situ hybridization experiments
showed completely coherent results: the Bovini probe Bt1 hybridized only to members
of the Bovini tribe and not to members of Caprini. Likewise, the Caprini probe Om1
hybridized only to members of the Caprini tribe and not to members of Bovini.
Hybridization signals were detected in the heterochromatic regions of every
acrocentric autosome, except for two pairs of autosomes from Capra
hircus that did not show hybridization to probe Om1. No signal was
detected on X and Y chromosomes or on bi-armed autosomes. Remarkably, probe Om1
showed almost 100% homology with a bacterial sequence reported in
Helicobacter pylori. 相似文献
984.
Diosmin is a glycosylated polyphenolic compound, commonly found in fruits and vegetables, which is utilized for the pharmacological formulation of some drugs. The interactions of diosmin to human serum albumin have been investigated by fluorescence, UV–visible, FTIR spectroscopy, native electrophoresis and protein–ligand docking studies. The fluorescence studies indicate that the binding site of the additive involves modifications of environment around Trp214 at the level of subdomain IIA. Combining the curve-fitting results of infrared Amide I′ band, the modifications of protein secondary structure have been estimated, indicating a decrease in α-helix structure following flavonoid binding. Data obtained by fluorescence and UV–visible spectroscopy, FTIR experiments and molecular modeling afforded a clear picture of the association mode of diosmin to HSA, suggesting that the primary binding site of diosmin is located in Sudlow's site I. Computational mapping confirms this observation suggesting that the possible binding site of diosmin is located in the hydrophobic cavity of subdomain IIA, whose microenvironment is able to help and stabilize the binding of the ligand in non-planar conformation. Moreover the binding of diosmin to HSA significantly contributes to protect the protein against degradation due to HCLO and Fenton reaction. 相似文献
985.
Stefania Bennici Gaetano Distefano Giuseppina Las Casas Mario Di Guardo Giuseppe Lana Ettore Pacini Stefano La Malfa Alessandra Gentile 《The Annals of applied biology》2019,175(1):29-41
Male gametophyte development is a critical phase of the plant life cycle due to its high sensitivity to environmental stresses. The rise in the average global temperature, often accompanied by extreme fluctuations, has an important impact on biological processes. Among those, male gametophytes are particularly sensitive to temperature stress during flower bud development and anthesis. Male gametophyte development was extensively studied in several plant species, but little information is available about the effects of temperature stress on male gametophyte development in the genus Citrus. We evaluated the effects of cold and hot temperatures during microsporogenesis and microgametogenesis on one of the most economically valuable citrus species, the “Comune” clementine (Citrus clementina Hort. ex. Tan.). The effect of constant temperature on the androecium was evaluated by a time course histological analysis performed on the anthers and by monitoring in vitro pollen germination. The results revealed how suboptimal hot and cold temperatures induce drastic alterations on the morphology of the tapetal cells, microspores and mature pollen grains. Shifting from the optimal temperature affected the timing of starch depletion in the anther walls, such as epidermis, endothecium and middle layer, influencing the pollen germination rate and pollen tube growth. To the best of our knowledge this is the first study attempting to assess how temperature stress affects male reproductive development in citrus. A better understanding of the mechanisms underlining male sterility will provide novel insights to elucidate the physiology of this agronomical important quality trait. 相似文献
986.