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101.
Nadezhda N. Sushchik Michail I. Gladyshev Elena S. Kravchuk Elena A. Ivanova Alexander V. Ageev Galina S. Kalachova 《Aquatic Ecology》2007,41(2):349-365
We studied composition and concentrations of fatty acids (FAs) in benthos from pebbly littoral region of the Yenisei River
in a sampling site near Krasnoyarsk city (Siberia, Russia) for 1 year from March 2003 to February 2004. Special attention
was paid to major long-chain polyunsaturated fatty acids (PUFAs) of the ω3 family: eicosapentaenoic acid (EPA, 20:5ω3) and
docosahexaenoic acids (DHA, 22:6ω3). In phytobenthos, which was dominated by diatoms, the annual maxima of EPA and DHA pool
occurred in spring and early summer. In zoobenthos, EPA and DHA pool peaked in autumn, due mainly to an increase of the biomass
of dominant taxa (gammarids) and to a moderate increase of the PUFA content per body weight. Seasonal peaks of EPA in overwintering
insect larvae (chironomids and caddisflies) generally coincided with those of biomass of these larvae, while there was no
such trend for amphipods and oligochaetes. In spring and early summer, the main part of ω3 PUFA, 40–97% of total amount, in
the littoral region was contained in biomass of producers, i.e., benthic microalgae, and in autumn it was transferred to primary
consumers—benthic invertebrates, which contained ∼76–93% of total ω3 PUFAs. 相似文献
102.
103.
Cavalcanti-de-Albuquerque Joao Paulo de-Souza-Ferreira Eduardo de Carvalho Denise Pires Galina Antonio 《Neurochemical research》2022,47(2):470-480
Neurochemical Research - Glucose and oxygen (O2) are vital to the brain. Glucose metabolism and mitochondria play a pivotal role in this process, culminating in the increase of reactive O2 species.... 相似文献
104.
Andrey V. Mardanov Galina B. Slododkina Alexander I. Slobodkin Alexey V. Beletsky Sergey N. Gavrilov Ilya V. Kublanov Elizaveta A. Bonch-Osmolovskaya Konstantin G. Skryabin Nikolai V. Ravin 《Applied and environmental microbiology》2015,81(3):1003-1012
Geoglobus acetivorans is a hyperthermophilic anaerobic euryarchaeon of the order Archaeoglobales isolated from deep-sea hydrothermal vents. A unique physiological feature of the members of the genus Geoglobus is their obligate dependence on Fe(III) reduction, which plays an important role in the geochemistry of hydrothermal systems. The features of this organism and its complete 1,860,815-bp genome sequence are described in this report. Genome analysis revealed pathways enabling oxidation of molecular hydrogen, proteinaceous substrates, fatty acids, aromatic compounds, n-alkanes, and organic acids, including acetate, through anaerobic respiration linked to Fe(III) reduction. Consistent with the inability of G. acetivorans to grow on carbohydrates, the modified Embden-Meyerhof pathway encoded by the genome is incomplete. Autotrophic CO2 fixation is enabled by the Wood-Ljungdahl pathway. Reduction of insoluble poorly crystalline Fe(III) oxide depends on the transfer of electrons from the quinone pool to multiheme c-type cytochromes exposed on the cell surface. Direct contact of the cells and Fe(III) oxide particles could be facilitated by pilus-like appendages. Genome analysis indicated the presence of metabolic pathways for anaerobic degradation of aromatic compounds and n-alkanes, although an ability of G. acetivorans to grow on these substrates was not observed in laboratory experiments. Overall, our results suggest that Geoglobus species could play an important role in microbial communities of deep-sea hydrothermal vents as lithoautotrophic producers. An additional role as decomposers would close the biogeochemical cycle of carbon through complete mineralization of various organic compounds via Fe(III) respiration. 相似文献
105.
Salavat?R. Nabiev Denis?A. Ovsyannikov Galina?V. Kopylova Daniil?V. Shchepkin Alexander?M. Matyushenko Natalia?A. Koubassova Dmitrii?I. Levitsky Andrey?K. Tsaturyan Sergey?Y. Bershitsky 《Biophysical journal》2015,109(2):373-379
A two-beam optical trap was used to measure the bending stiffness of F-actin and reconstructed thin filaments. A dumbbell was formed by a filament segment attached to two beads that were held in the two optical traps. One trap was static and held a bead used as a force transducer, whereas an acoustooptical deflector moved the beam holding the second bead, causing stretch of the dumbbell. The distance between the beads was measured using image analysis of micrographs. An exact solution to the problem of bending of an elastic filament attached to two beads and subjected to a stretch was used for data analysis. Substitution of noncanonical residues in the central part of tropomyosin with canonical ones, G126R and D137L, and especially their combination, caused an increase in the bending stiffness of the thin filaments. The data confirm that the effect of these mutations on the regulation of actin-myosin interactions may be caused by an increase in tropomyosin stiffness. 相似文献
106.
Alexey?A. Malygin Dmitri?M. Graifer Maria?I. Meschaninova Aliya?G. Venyaminova Olesya?A. Krumkacheva Matvey?V. Fedin Galina?G. Karpova Elena?G. Bagryanskaya 《Biophysical journal》2015,109(12):2637-2643
mRNAs are involved in complicated supramolecular complexes with human 40S and 80S ribosomes responsible for the protein synthesis. In this work, a derivative of nonaribonucleotide pUUCGUAAAA with nitroxide spin labels attached to the 5′-phosphate and to the C8 atom of the adenosine in sixth position (mRNA analog) was used for studying such complexes using double electron-electron resonance/pulsed electron-electron double resonance spectroscopy. The complexes were assembled with participation of tRNAPhe, which targeted triplet UUC of the derivative to the ribosomal peptidyl site and predetermined location of the adjacent GUA triplet coding for Val at the aminoacyl (A) site. The interspin distances were measured between the two labels of mRNA analog attached to the first nucleotide of the peptidyl site bound codon and to the third nucleotide of the A site bound codon, in the absence/presence of second tRNA bound at the A site. The values of the obtained interspin distances agree with those calculated for available near-atomic structures of similar complexes of 40S and 80S ribosomes, showing that neither 60S subunit nor tRNA at the A site have a noticeable effect on arrangement of mRNA at the codon-anticodon interaction area. In addition, the shapes of distance distributions in four studied ribosomal complexes allowed conclusions on conformational flexibility of mRNA in these complexes. Overall, the results of this study are the first, to our knowledge, demonstration of double electron-electron resonance/pulsed electron-electron double resonance application for measurements of intramolecular distances in multicomponent supramolecular complexes involving intricate cellular machineries and for evaluating dynamic properties of ligands bound to these machineries. 相似文献
107.
Ariel Jaitovich Martín Angulo Emilia Lecuona Laura A. Dada Lynn C. Welch Yuan Cheng Galina Gusarova Ermelinda Ceco Chang Liu Masahiko Shigemura Esther Barreiro Cam Patterson Gustavo A. Nader Jacob I. Sznajder 《The Journal of biological chemistry》2015,290(14):9183-9194
Patients with chronic obstructive pulmonary disease, acute lung injury, and critical care illness may develop hypercapnia. Many of these patients often have muscle dysfunction which increases morbidity and impairs their quality of life. Here, we investigated whether hypercapnia leads to skeletal muscle atrophy. Mice exposed to high CO2 had decreased skeletal muscle wet weight, fiber diameter, and strength. Cultured myotubes exposed to high CO2 had reduced fiber diameter, protein/DNA ratios, and anabolic capacity. High CO2 induced the expression of MuRF1 in vivo and in vitro, whereas MuRF1−/− mice exposed to high CO2 did not develop muscle atrophy. AMP-activated kinase (AMPK), a metabolic sensor, was activated in myotubes exposed to high CO2, and loss-of-function studies showed that the AMPKα2 isoform is necessary for muscle-specific ring finger protein 1 (MuRF1) up-regulation and myofiber size reduction. High CO2 induced AMPKα2 activation, triggering the phosphorylation and nuclear translocation of FoxO3a, and leading to an increase in MuRF1 expression and myotube atrophy. Accordingly, we provide evidence that high CO2 activates skeletal muscle atrophy via AMPKα2-FoxO3a-MuRF1, which is of biological and potentially clinical significance in patients with lung diseases and hypercapnia. 相似文献
108.
109.
Galina M. Zats Marina Kovaliov Amnon Albeck Shimon Shatzmiller 《Journal of peptide science》2015,21(6):512-519
Antimicrobial peptides (AMPs) appear to be good candidates for the development of new antibiotic drugs. We describe here the synthesis of peptidomimetic compounds that are based on a benzodiazepine scaffold flanked with positively charged and hydrophobic amino acids. These compounds mimic the essential properties of cationic AMPs. The new design possesses the benzodiazepine scaffold that is comprised of two glycine amino acids and which confers flexibility and aromatic hydrophobic ‘back’, and two arms used for further synthesis on solid phase for incorporation of charged and hydrophobic amino acids. This approach allowed us a better understanding of the influence of these features on the antimicrobial activity and selectivity. A novel compound was discovered which has MICs of 12.5 µg/ml against Staphylococcus aureus and 25 µg/ml against Escherichia coli, similar to the well‐known antimicrobial peptide MSI‐78. In contrast to MSI‐78, the above mentioned compound has lower lytic effect against mammalian red blood cells. These peptidomimetic compounds will pave the way for future design of potent synthetic mimics of AMPs for therapeutic and biomedical applications. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
110.
Alexey Teplyakov Galina Obmolova Gabriela Canziani Yonghong Zhao Lester Gutshall Sonia S. Jung Gary L. Gilliland 《Journal of molecular recognition : JMR》2011,24(4):570-575
Alzheimer's disease is a progressive neurodegenerative disease characterized by extracellular deposits of β‐amyloid (Aβ) plaques. Aggregation of the Aβ42 peptide leading to plaque formation is believed to play a central role in Alzheimer's disease pathogenesis. Anti‐Aβ monoclonal antibodies can reduce amyloid plaques and could possibly be used for immunotherapy. We have developed a monoclonal antibody C706, which recognizes the human Aβ peptide. Here we report the crystal structure of the antibody Fab fragment at 1.7 Å resolution. The structure was determined in two crystal forms, P21 and C2. Although the Fab was crystallized in the presence of Aβ16, no peptide was observed in the crystals. The antigen‐binding site is blocked by the hexahistidine tag of another Fab molecule in both crystal forms. The poly‐His peptide in an extended conformation occupies a crevice between the light and heavy chains of the variable domain. Two consecutive histidines (His4–His5) stack against tryptophan residues in the central pocket of the antigen‐binding surface. In addition, they form hydrogen bonds to the acidic residues at the bottom of the pocket. The mode of his‐tag binding by C706 resembles the Aβ recognition by antibodies PFA1 and WO2. All three antibodies recognize the same immunodominant B‐cell epitope of Aβ. By similarity, residues Phe–Arg–His of Aβ would be a major portion of the C706 epitope. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献