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191.
O. L. Makarova 《Entomological Review》2009,89(9):1177-1193
According to the data of four-year sampling, the territory of the Pinega Reserve (Arkhangelsk Province) is populated by more
than 117 gamasid mite species belonging to 18 families. A relative richness of this fauna is obviously associated with intensive
karst processes. A number of species (arctic, Siberian, mountainous) is limited to karst localities characterized by low soil
temperature and a short vegetation period. When comparing the local Mesostigmata faunas from different regions, it was suggested
that only species lists of unspecialized free-leaving forms should be used. Changes in the species richness of separate families
and their fraction in the total suborder diversity along the latitudinal gradient from dry steppes to polar deserts are individual,
reflecting different ecological potencies. The zone of deciduous forests is characterized by the richest fauna of Mesostigmata
as a whole and of the majority of its families. The northern boundaries for the distribution of separate families are outlined.
The number of free-leaving species in the families Ascidae, Phytoseiidae, and Zerconidae varies most smoothly along the latitudinal
gradient. Even in polar deserts, Ascidae and Phytoseiidae are represented by more than a single species. It is in the taiga
that the family Ascidae becomes the most diverse among Mesostigmata. In the tundra zone, this tendency is more pronounced,
and in polar deserts this family constitutes 70–83% of species in local faunas, represented mainly by the genus Arctoseius. 相似文献
192.
Cellular DNA polymerases belong to several families and carry out different functions. Highly accurate replicative DNA polymerases
play the major role in cell genome replication. A number of new specialized DNA polymerases were discovered at the turn of
XX–XXI centuries and have been intensively studied during the last decade. Due to the special structure of the active site,
these enzymes efficiently perform synthesis on damaged DNA but are characterized by low fidelity. Human DNA polymerase iota
(Pol ι) belongs to the Y-family of specialized DNA polymerases and is one of the most error-prone enzymes involved in DNA
synthesis. In contrast to other DNA polymerases, Pol ι is able to use noncanonical Hoogsteen interactions for nucleotide base
pairing. This allows it to incorporate nucleotides opposite various lesions in the DNA template that impair Watson-Crick interactions.
Based on the data of X-ray structural analysis of Pol ι in complexes with various DNA templates and dNTP substrates, we consider
the structural peculiarities of the Pol ι active site and discuss possible mechanisms that ensure the unique behavior of the
enzyme on damaged and undamaged DNA. 相似文献
193.
Elizabeth M. Fozo Kira S. Makarova Svetlana A. Shabalina Natalya Yutin Eugene V. Koonin Gisela Storz 《Nucleic acids research》2010,38(11):3743-3759
Small, hydrophobic proteins whose synthesis is repressed by small RNAs (sRNAs), denoted type I toxin–antitoxin modules, were first discovered on plasmids where they regulate plasmid stability, but were subsequently found on a few bacterial chromosomes. We used exhaustive PSI-BLAST and TBLASTN searches across 774 bacterial genomes to identify homologs of known type I toxins. These searches substantially expanded the collection of predicted type I toxins, revealed homology of the Ldr and Fst toxins, and suggested that type I toxin–antitoxin loci are not spread by horizontal gene transfer. To discover novel type I toxin–antitoxin systems, we developed a set of search parameters based on characteristics of known loci including the presence of tandem repeats and clusters of charged and bulky amino acids at the C-termini of short proteins containing predicted transmembrane regions. We detected sRNAs for three predicted toxins from enterohemorrhagic Escherichia coli and Bacillus subtilis, and showed that two of the respective proteins indeed are toxic when overexpressed. We also demonstrated that the local free-energy minima of RNA folding can be used to detect the positions of the sRNA genes. Our results suggest that type I toxin–antitoxin modules are much more widely distributed among bacteria than previously appreciated. 相似文献
194.
Shmendel E. V. Bakhareva S. A. Makarova D. M. Chernikov I. V. Morozova N. G. Chernolovskaya E. L. Zenkova M. A. Maslov M. A. 《Russian Journal of Bioorganic Chemistry》2020,46(6):1250-1260
Russian Journal of Bioorganic Chemistry - New uncharged gemini-amphiphiles have been synthesized. A series of cationic liposomes based on the polycationic amphiphile... 相似文献
195.
196.
A new gamasid mite species belonging to the genus Arctoseius Thor, 1930 is described from Russia. Arctoseius koltschaki
sp. n. is distributed in the plain and mountain tundras from Khibiny Mountains to Chukotka on the north and to West Sayan Mountains on the south. A diagnosis and a key for identification of species comprising the multidentatus species-group (Arctoseius multidentatus Evans, 1955; Arctoseius wisniewskii Gwiazdowicz & Kamczyc, 2009; Arctoseius sexsetus Lindquist & Makarova, 2011; Arctoseius haarlovi Lindquist & Makarova, 2011; and Arctoseius koltschaki
sp. n.) are given. 相似文献
197.
Makarova AM Lebedeva TV Nassar T Higazi AA Xue J Carinato ME Bdeir K Cines DB Stepanova V 《The Journal of biological chemistry》2011,286(26):23044-23053
Urokinase plasminogen activator (uPA) and PA inhibitor type 1 (PAI-1) are elevated in acute lung injury, which is characterized by a loss of endothelial barrier function and the development of pulmonary edema. Two-chain uPA and uPA-PAI-1 complexes (1-20 nM) increased the permeability of monolayers of human pulmonary microvascular endothelial cells (PMVECs) in vitro and lung permeability in vivo. The effects of uPA-PAI-1 were abrogated by the nitric-oxide synthase (NOS) inhibitor L-NAME (N(D)-nitro-L-arginine methyl ester). Two-chain uPA (1-20 nM) and uPA-PAI-1 induced phosphorylation of endothelial NOS-Ser(1177) in PMVECs, which was followed by generation of NO and the nitrosylation and dissociation of β-catenin from VE-cadherin. uPA-induced phosphorylation of eNOS was decreased by anti-low density lipoprotein receptor-related protein-1 (LRP) antibody and an LRP antagonist, receptor-associated protein (RAP), and when binding to the uPA receptor was blocked by the isolated growth factor-like domain of uPA. uPA-induced phosphorylation of eNOS was also inhibited by the protein kinase A (PKA) inhibitor, myristoylated PKI, but was not dependent on PI3K-Akt signaling. LRP blockade and inhibition of PKA prevented uPA- and uPA-PAI-1-induced permeability of PMVEC monolayers in vitro and uPA-induced lung permeability in vivo. These studies identify a novel pathway involved in regulating PMVEC permeability and suggest the utility of uPA-based approaches that attenuate untoward permeability following acute lung injury while preserving its salutary effects on fibrinolysis and airway remodeling. 相似文献
198.
Makarova NA Zakharov IuM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2011,97(8):877-884
Structurally-functional myocardium parameters and their interconnection with erythropoietin and tumour necrosis factor-alpha levels in blood plasma of patients with heart failure were analysed. Prevalence of erythropoietin over tumour necrosis factor-alpha in blood had positive effect on myocardium-contraction ability under acute heart failure. Improvement of pumped cardiac function was not registered under prevalence of erythropoietin over tumour necrosis faetor-a in blood of patients with chronic heart failure. 相似文献
199.
200.