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11.
E. G. Plotnikova I. P. Solyanikova D. O. Egorova E. S. Shumkova L. A. Golovleva 《Microbiology》2012,81(2):143-153
The strain Rhodococcus ruber P25 utilizes 4-chlorobiphenyl (4CB) and 4-chlorobenzoic acid (4CBA) as sole carbon and energy sources. 4CB degradation by
washed cells of strain P25 was accompanied by transient formation of 4CBA, followed by its utilization and release of equimolar
amounts of chloride ions into the medium. The strain R. ruber P25 possessed active enzyme systems providing 4CBA degradation via the stages of formation of intermediates, para-hydroxybenzoate (PHBA) and protocatechuic acid (PCA), to compounds of the basic metabolism. The involvement of protocatechuate
4,5-dioxygenase in 4CBA degradation by rhodococci was revealed. It was established that the initial stage of 4CBA degradation
(dehalogenation) in the strain R. ruber P25 was controlled by the fcbA and fcbB genes encoding 4-CBA-CoA ligase and 4-CBA-CoA dehalogenase, respectively. The genes encoding 4CBA dehalogenase components
have not been previously detected and characterized in bacteria of the genus Rhodococcus. 相似文献
12.
E. N. Egorova 《Biology Bulletin》2016,43(7):619-627
Bivalves collected in Vestfold Hills during the 55th Russian Antarctic Expedition (RAE, 2009?2010) are represented by five species. Four of them (Laternula elliptica, Thracia meridionalis, Adamussium colbecki, and Philobrya sublaevis) were collected in the sediments that filled the coastal lake terraces during the Holocene; these species are still abundant on the Antarctic shelf at present. Bivalves were found in eight samples, with L. elliptica shells and fragments thereof found in seven of those samples. The sample collected near Deep Lake had the most diverse species composition, as it contained all four species named above. Shells of named species widely occurring in present-day Antarctica were found high above sea level in the marine sediments of the oasis. This indicate to the similarity of the oasis habitats in the past and the recent marine conditions. Fragments of shells of the fifth (now extinct) species Ruthipecten tuftsensis were found in glacial–marine sediments of the Marine Plain dating back to the late Pleistocene. The present study of fossil bivalves from the late Cenozoic marine sediments in Vestfold Hills is the first of its kind in Russia. 相似文献
13.
Kurbatova EA Semenov BF Egorova NB Efremova VN Gruber IM Semenova IB Kushchenko OM 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2004,(3):34-39
The experimental study of the immunostimulating activity of therapeutic bacterial polycomponent vaccine VP-4 and prophylactic vaccine grippol, introduced both separately and in combination, on mice infected with Salmonella typhimurium, used as a model. Both preparations were found to produce an immunomodulating effect. The combined subcutaneous injection of VP-4 and grippol did not decrease their immunostimulating activity, but their separate administration at an interval of 14 days resulted in essential decrease in the protective activity of each of these two preparations. As shown on the model of Klebsiella infection in mice, challenged 4 weeks after immunization, VP-4 ensured the survival of 78.6% of mice, while after the injection of grippol their survival rate was not different from that of the group of intact animals. The evaluation of the immunostimulating activity of these preparations under the conditions of the prophylaxis of influenza and acute respiratory infections in organized groups of children revealed that the use of VP-4 alone or grippol in combination with VP-4 considerably decreased the number of secondary bacterial complications in children. 相似文献
14.
O. A. Torgunakova V. E. Chrisanfov V. K. Prizenko A. K. Bogeruk T. A. Egorova S. K. Semyenova 《Russian Journal of Genetics》2012,48(1):93-100
Polymorphism of the mitochondrial cyt b gene was examined in 35 individuals of common carp and wild common carp (Cyprinus carpio L.). The fish examined represented two natural populations from Khabarovsk krai (Ac and Am), Volga wild common carp, Don
wild common carp, and two common carp breeds, Ropsha (strains BB and MM) common carp and Hungarian common carp. The highest
level of nucleotide (π) and haplotype (h) diversity was detected in two strains of Ropsha common carp (MM, π = 0.67%, h = 0.7; and BB, π = 0.21%, h = 0.9) and in one population (Am) of Amur wild common carp (π = 0.26%; h = 0.6). The second population of Amur wild common carp (Ac) and Hungarian common carp were characterized by lower variation
estimates (π = 0.035%, h = 0.4; and π = 0.09%, h = 0.7, respectively). Genetic homogeneity was demonstrated for the populations of Volga and Don wild common carp (π = 0,
h = 0). In the sample of the cyt b sequences examined, three lineages were identified. Lineages I and II united all haplotypes of the Am Amur wild common carp
along with two haplotypes of Ropsha common carp, strain MM. The third lineage (III) was formed by the haplotypes of three
individuals of Ropsha common carp strain MM, all representatives of Ropsha common carp strain BB, Hungarian common carp, Ac
Amur wild common carp, and Don and Volga wild common carps. Statistically significant amino acid differences were observed
only for the sequences, corresponding to haplotypes of lineage III, and the sum of sequences of lineages I and II. Effectiveness
of different types of markers to differentiate the two subspecies of European and Amur wild common carp (C. c. carpio and C. c. haematopterus) is discussed, as well as the issues of the origin and dispersal of Russian common carp and wild common carp breeds. 相似文献
15.
Ryanne JM Lemmens Annick AA Timmermans Yvonne JM Janssen-Potten Rob JEM Smeets Henk AM Seelen 《BMC neurology》2012,12(1):1-17
Background
Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.Methods
A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.Results
Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.Conclusions
Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed. 相似文献16.
Nielsen J; Peixoto AA; Piccin A; Costa R; Kyriacou CP; Chalmers D 《Molecular biology and evolution》1994,11(6):839-853
The region of the clock gene period (per) that encodes a repetitive tract
of threonine-glycine (Thr-Gly) pairs has been compared between Dipteran
species both within and outside the Drosophilidae. All the non-
Drosophilidae sequences in this region are short and present a remarkably
stable picture compared to the Drosophilidae, in which the region is much
larger and extremely variable, both in size and composition. The
accelerated evolution in the repetitive region of the Drosophilidae appears
to be mainly due to an expansion of two ancestral repeats, one encoding a
Thr-Gly dipeptide and the other a pentapeptide rich in serine, glycine, and
asparagine or threonine. In some drosophilids the expansion involves a
duplication of the pentapeptide sequence, but in Drosophila pseudoobscura
both the dipeptide and the pentapeptide repeats are present in larger
numbers. In the nondrosophilids, however, the pentapeptide sequence is
represented by one copy and the dipeptide by two copies. These observations
fulfill some of the predictions of recent theoretical models that have
simulated the evolution of repetitive sequences.
相似文献
17.
M B Garber A D Yaremchuk M A Tukalo S P Egorova C Berthet-Colominas R Leberman 《Journal of molecular biology》1990,213(4):631-632
Crystals have been obtained of seryl-tRNA synthetase from the extreme thermophile Thermus thermophilus, using mixed solutions of ammonium sulphate and methane pentane diol. The crystals are very stable and diffract to at least 2 A. The crystals are monoclinic (space group P21) with cell parameters a = 87.1 A, b = 126.9 A, c = 63.5 A and beta = 109.7 degrees. 相似文献
18.
19.
I.A. Tsaplina A.E. Zhuravlev M.A. Egorova T.I. Bogdanov E.N. Krasil’nikova L.M. Zakharchuk T.F. Kondrat’ev 《Microbiology》2010,79(1):13-22
For cultures of moderately thermophilic chemolithotrophic bacteria Sulfobacillus sibiricus N1 and SSO, S. thermosulfidooxidans subsp. asporogenes 41, and the thermotolerant strain S. thermotolerans Kr1 grown under forced aeration and in a high medium layer without aeration, growth characteristics, substrate consumption, and exometabolite formation were compared. Sulfobacilli grown under oxygen limitation exhibited greater generation time, longer growth period, cell yield decreased by from 40 to 85% (depending on the strain), suppressed cell respiration ( demonstrated for S. sibiricus N1 ), accumulation of exometabolites (acetate and propionate) in the medium, and emergence of resting forms. For strains N1, SSO, and Kr1, oscillations of Fe(II) and Fe(III) content in the medium were revealed. For S. sibiricus N1 and S. thermotolerans Kr1, grown under hypoxia (0.07% O2 in the gas phase), coupling of substrate oxidation with Fe(III) reduction was revealed, as well as utilization of Fe(III) as an electron acceptor alternative to oxygen. The role of labile energy and constructive metabolism for survival of sulfobacilli under diverse conditions is discussed. 相似文献
20.
Tatiana Egorova Nikita Biziaev Alexey Shuvalov Elizaveta Sokolova Sabina Mukba Konstantin Evmenov Maria Zotova Artem Kushchenko Ekaterina Shuvalova Elena Alkalaeva 《Nucleic acids research》2021,49(19):11181
eIF3j is one of the eukaryotic translation factors originally reported as the labile subunit of the eukaryotic translation initiation factor eIF3. The yeast homolog of this protein, Hcr1, has been implicated in stringent AUG recognition as well as in controlling translation termination and stop codon readthrough. Using a reconstituted mammalian in vitro translation system, we showed that the human protein eIF3j is also important for translation termination. We showed that eIF3j stimulates peptidyl-tRNA hydrolysis induced by a complex of eukaryotic release factors, eRF1-eRF3. Moreover, in combination with the initiation factor eIF3, which also stimulates peptide release, eIF3j activity in translation termination increases. We found that eIF3j interacts with the pre-termination ribosomal complex, and eRF3 destabilises this interaction. In the solution, these proteins bind to each other and to other participants of translation termination, eRF1 and PABP, in the presence of GTP. Using a toe-printing assay, we determined the stage at which eIF3j functions – binding of release factors to the A-site of the ribosome before GTP hydrolysis. Based on these data, we assumed that human eIF3j is involved in the regulation of translation termination by loading release factors into the ribosome. 相似文献