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2.
L P Gorshunova V A Maksimova-Todorova V A Romanov K A Vanag A V Nabokova 《Biulleten' eksperimental'no? biologii i meditsiny》1978,85(5):567-569
Specific antigen was identified by the immunofluorescent test in the walls of the brain blood vessels, in the neurons, and in the glial cells of albino newborn mice and Syrian hamsters inoculated subcutaneously with 4 different batches of live measles vaccine. The pathomorphological test of the brain tissue revealed mainly vascular disturbances. The data obtained testify to the presence of residual neurotropism in the attenuated measles virus (strain "L-16"). 相似文献
3.
V. N. Kryazhev V. V. Romanov V. A. Shirokov 《Russian Journal of Bioorganic Chemistry》2011,37(7):779-785
The review focuses on the most important studies performed during the last eight years on the physical and chemical modifications of starch, starch graft copolymers, and starch ethers; on the development of biodegradable starch-based materials; and on various applications of numerous starch derivatives. An analysis of the recent publications allows the conclusion that considerable advances have been made in the chemistry and technology of starch derivatives as biodegradable “green” reagents and products, which are becoming increasingly important for technological applications due to the wide occurrence of starch, the ease of its processing, and its nature as a renewable resource. 相似文献
4.
Electromagnetic radiation from an anisotropic plasma slab formed by ionization of matter in the field of a high-power femtosecond pulse is studied. It is shown that the growth of initial field perturbations in the course of Weibel instability is accompanied by the generation of nonmonochromatic radiation with a characteristic frequency on the order of the instability growth rate. It is found that perturbations with characteristic scale lengths less than or on the order of the ratio of the speed of light to the Langmuir frequency are excited and radiated most efficiently, provided that the slab is thicker than this ratio. 相似文献
5.
Merzlikina NV Buravkova LB Romanov YA 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2004,11(2):P193-P194
Mesenchymal stem cells (MSCs) are specific cells capable of long-term proliferation and differentiation into various stromal tissue cell types. The state of MSCs depends on the cellular microenvironment and several soluble factors. We proposed that gravity could, in addition, influence MSCs features. To prove this hypothesis, we studied the effects of prolonged clinorotation on cultured human MSC morphology, proliferation rate and expression of specific cellular markers. Human bone marrow-derived MSCs were isolated by Histopaque-1.077 density centrifugation and cultured in DMEM-LG with 10% FBS. MSC cultures were composed of fibroblastoid cells negative for hemopoietic cell markers and positive for ASMA, collagen-1, fibronectin, CD54, CD105 and CD106. Cells were exposed to clinorotation from 1 hour to 10 days. It was shown that the proliferative rate was decreased in experimental cultures as compared to cells growing in normal conditions. Clinorotated MSCs appeared more flattened and reached confluence at a lower cell density. The obtained results suggest that cultured human mesenchymal stem cells sense the changes in gravity vector and may respond to microgravity by altered functional activity. 相似文献
6.
Robert Lam Vladimir Romanov Kathy Johns Kevin P. Battaile Jean Wu‐Brown Jennifer L. Guthrie Robert P. Hausinger Emil F. Pai Nickolay Y. Chirgadze 《Proteins》2010,78(13):2839-2848
Urease plays a central role in the pathogenesis of Helicobacter pylori in humans. Maturation of this nickel metalloenzyme in bacteria requires the participation of the accessory proteins UreD (termed UreH in H. pylori), UreF, and UreG, which form sequential complexes with the urease apoprotein as well as UreE, a metallochaperone. Here, we describe the crystal structure of C‐terminal truncated UreF from H. pylori (residues 1–233), the first UreF structure to be determined, at 1.55 Å resolution using SAD methods. UreF forms a dimer in vitro and adopts an all‐helical fold congruent with secondary structure prediction. On the basis of evolutionary conservation analysis, the structure reveals a probable binding surface for interaction with other urease components as well as key conserved residues of potential functional relevance. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
7.
D. A. Gryadunov I. A. Getman S. I. Chizhova V. M. Mikhailovich A. S. Zasedatelev G. A. Romanov 《Molecular Biology》2011,45(6):894-903
A method of multiplex polymerase chain reaction (PCR) followed by hybridization on a hydrogel oligonucleotide biochip was
developed for simultaneous identification of ten different transgenic elements of plant DNA in food and feed products. The
biochip contained 22 immobilized oligonucleotide probes that were intended for (1) detection of plant DNA, (2) determination
of plant species (soybean, maize, potato, and rice), and (3) identification of transgenic elements, including sequences of
35S CaMV, 35S FMV, rice actin gene promoters, nos, 35S CaMV, ocs, pea rbcS1 gene terminators, and bar, gus, and nptII marker genes. The limit of detection was 0.5% for genetically modified (GM) soybean and maize in the analyzed samples. The
tests on food and feed products using the developed approach and real-time PCR showed full agreement in determination of transgenic
DNA in the samples. The proposed assay can be used for selection of GM samples by screening food and feed products for subsequent
quantitative determination of GM component based on the identified transgene. 相似文献
8.
Alan Birchall M. Puncher J. Harrison A. Riddell M. R. Bailey V. Khokryakov S. Romanov 《Radiation and environmental biophysics》2010,49(2):203-212
Epidemiological studies of the relationship between risk and internal exposure to plutonium are clearly reliant on the dose
estimates used. The International Commission on Radiological Protection (ICRP) is currently reviewing the latest scientific
information available on biokinetic models and dosimetry, and it is likely that a number of changes to the existing models
will be recommended. The effect of certain changes, particularly to the ICRP model of the respiratory tract, has been investigated
for inhaled forms of 239Pu and uncertainties have also been assessed. Notable effects of possible changes to respiratory tract model assumptions are
(1) a reduction in the absorbed dose to target cells in the airways, if changes under consideration are made to the slow clearing
fraction and (2) a doubling of absorbed dose to the alveolar region for insoluble forms, if evidence of longer retention times
is taken into account. An important factor influencing doses for moderately soluble forms of 239Pu is the extent of binding of dissolved plutonium to lung tissues and assumptions regarding the extent of binding in the
airways. Uncertainty analyses have been performed with prior distributions chosen for application in epidemiological studies.
The resulting distributions for dose per unit intake were lognormal with geometric standard deviations of 2.3 and 2.6 for
nitrates and oxides, respectively. The wide ranges were due largely to consideration of results for a range of experimental
data for the solubility of different forms of nitrate and oxides. The medians of these distributions were a factor of three
times higher than calculated using current default ICRP parameter values. For nitrates, this was due to the assumption of
a bound fraction, and for oxides due mainly to the assumption of slower alveolar clearance. This study highlights areas where
more research is needed to reduce biokinetic uncertainties, including more accurate determination of particle transport rates
and long-term dissolution for plutonium compounds, a re-evaluation of long-term binding of dissolved plutonium, and further
consideration of modeling for plutonium absorbed to blood from the lungs. 相似文献
9.
VEGF-induced mobilization of caveolae and increase in permeability of endothelial cells 总被引:10,自引:0,他引:10
Chen J Braet F Brodsky S Weinstein T Romanov V Noiri E Goligorsky MS 《American journal of physiology. Cell physiology》2002,282(5):C1053-C1063
Glomerular epithelial cells (GEC) are aknown site of vascular endothelial growth factor (VEGF) production. Weestablished immortalized rat GEC, which retained the ability to produceVEGF. The isoforms expressed by GEC were defined as VEGF-205, -188, -120, and -164. The electrical resistance of endothelial cells culturedon GEC-conditioned matrix, an indicator of the permeability ofmonolayers to solutes, was significantly increased by the treatment with the neutralizing polyclonal antibodies to VEGF and decreased byVEGF-165. Transfection of endothelial cells with green fluorescence protein-caveolin construct and intravital confocal microscopy showedthat VEGF results in a rapid appearance of transcellular elongatedstructures decorated with caveolin. Transmission electron microscopy ofendothelial cells showed that caveolae undergo rapid internalizationand fusion 30 min after application of VEGF-165. Later (36 h),endothelial cells pretreated with VEGF developed fenestrae and showed adecrease in electrical resistance. Immunoelectron microscopy ofglomeruli confirmed VEGF localization to podocytes and in the basementmembrane. In summary, immortalized GEC retain the ability to synthesizeVEGF. Matrix-deposited and soluble VEGF leads to the enhancement ofcaveolae expression, their fission and fusion, formation of elongatedcaveolin-decorated structures, and eventual formation of fenestrae,both responsible for the increase in endothelial permeability. 相似文献
10.
A survey was conducted to determine the levels of fumonisins B1 and B2 in corn and corn-based products available in Colombia
for human and animal consumption. A total of 120 samples were analyzed by acetonitrile-water extraction, cleanup with a strong-anion-exchange
column, and liquid chromatography with o-phthaldialdehyde-2-mercaptoethanol derivatization and fluorescence detection. The
samples of corn and corn-based products for animal intake were taken at different feed manufacturing plants, whereas the samples
used for human foods where purchased from local retail stores. The number of positive samples for fumonisin B1 was 20.0% higher
in corn and corn-based products for animal intake (75.0%) than in corn and corn-based products for human consumption (55.0%).
The levels of fumonisin B1 were also higher in corn and corn-based products for animal intake (mean = 694 μg/kg; range = 32–2964
μg/kg), than in corn and corn-based products for human intake (mean = 218 μg/kg; range = 24–2170 μg/ kg). The incidence and
levels of fumonisin B2 were lower than those for fumonisin B1. Corn and corn-based products for animal consumption had an
incidence of fumonisin B2 of 58.3%, with a mean value of 283 μg/kg, and a range of 44–987 μg/kg. The incidence of fumonisin
B2 in corn-based products for human intake was 35.0%, with a mean value of 118 μg/kg and a range of 21–833 μg/kg. The highest
incidence and levels of fumonisins were found in samples of hominy feed, with concentrations ranging from 86 to 2964 μg/kg
fumonisin B1 and 57 to 987 μg/kg fumonisin B2. 相似文献