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991.
R. N. Khramov I. M. Santalova L. I. Fakhranurova A. A. Manokhin N. B. Simonova D. I. Rzhevsky A. N. Murashev 《Biophysics》2010,55(3):447-452
The action of solar light transformed by special screens has been studied on CD-1 male mice. In the active control group,
mice were irradiated through screens absorbing the UV-component. In the experimental group, screens transforming the UV-component
into the orange-red light were used. In the active control, changes in the swimming activity, as compared to the same parameter
before irradiation, were manifested much less than in animals of the experimental group. A morphological analysis showed changes
in the structure of all cardiomyocyte organelles studied: the relative area of mitochondria in the experimental mice increased
by more than 20% compared to intact animals (p < 0.05). A significant increase in the area of the sarcoplasmic reticulum, by 23.4% (p < 0.05), and in the volume of the myofibrillar apparatus, by 19.4% (p < 0.05), was detected. The results of our experiment show that the irradiation with using an additional orangered component
improves the physical endurance 1.5 times and initiates morphogenetic processes in cardiac muscle cells. 相似文献
992.
DNA- and RNA-binding proteins of chromatin from Escherichia coli 总被引:3,自引:0,他引:3
The different proteins present in chromatin of Escherichia coli have been analyzed by a variety of techniques. The chromatin was isolated using a previously published procedure (Sj?stad, K., Fadnes, P., Krüger, P.G. Lossius, I. and Kleppe, K. (1982) J. Gen. Microbiol. 128, 3037) and solubilized by the action of micrococcal nuclease or DNAase I. The DNA-protein and RNA-protein complexes thus obtained were purified by sucrose gradient centrifugation and isopycnic gradient centrifugation in metrizamide in low ionic strength. The protein: DNA ratio of the DNA-protein complexes was estimated from the latter method and found to be approx. 1.75. The protein components were analyzed further by one- and two-dimensional gel electrophoresis. Approx. 15 major polypeptides were detected in the DNA-protein complex, whereas 10 were present in the RNA-protein complex. The majority of the polypeptides in both complexes had acidic isoelectric pH. The polypeptides in the two complexes differed markedly and only two polypeptides, having molecular weights of 57,000 and 37,000, respectively, were found to be common in both complexes. In agreement with earlier studies, the basic protein HU was not present in the DNA-protein complex. Affinity studies of the proteins from chromatin using DNA- and RNA-Sepharose columns in general confirmed the above conclusions. The two-dimensional gel electrophoretic patterns of the proteins in the different complexes were compared with those of proteins in the inner and outer membranes. Only one of the major polypeptides present in the inner membrane, having a molecular weight of 57,000, was enriched in the DNA-protein complex. 相似文献
993.
A. Veres L. Nyeste I. Kurucz L. Kirchknopf L. Szigeti J. Holl 《Biotechnology and bioengineering》1981,23(2):391-404
A fermentation system with a plug scheme unit has been developed, offering a variety of solutions to measurement, control, and operational problems. By means of the program unit, e.g., automatic pH control assigned to the dynamic of batch cultures and the feed of different ingredients controlled by a time program or a given variable have been solved. The continuous culture volume was controlled by a level controlled by a level controller equipped with a photosensor. A method was developed for variable control that provide information on the activity of the culture, and allows direct measurement of the different rate values, e.g., generation time or specific product formation rate. Applicability of the direct measurement of generation time is presented in the qualification of molasses and in a static off-line optimization process. 相似文献
994.
995.
996.
L I Pavlova N M Nikitiuk L A Nefedova T F Chernysheva A P Alliluev 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(7):65-67
A total of 1 968 persons aged 18-20 years belonging to organized groups were immunized with different doses of polysaccharide meningococcal divaccine, groups A and C, by means of syringes and jet injectors under the conditions of a controlled epidemiological trial. Systemic reactions to the injection of the preparation were found to be absent. Local reactions manifested by inflammation, swelling and tenderness at the site of injection were faintly pronounced and disappeared in 48 hours, which is indicative of low reactogenicity of the preparation under study. 相似文献
997.
T I Titova T N Sidorova S A Radkevich N G Antsiferova A F Moroz 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(8):80-84
The influence of immunization with P. aeruginosa vaccine on the immune status of volunteer donors has been studied. Immunization with P. aeruginosa vaccine in doses of 0.5-0.5-1.0 ml at intervals of 7 days has been found to lead to the 13-fold increase of the titer of specific antibodies, lasting for 3-4 months, which ensures the possibility of obtaining anti-P. aeruginosa hyperimmune plasma with standard titers. The injection of P. aeruginosa vaccine to donors leads to the activation of humoral immunity simultaneously with the increase of the absolute and relative number of rosette-forming B-lymphocytes without essential changes in the amount of rosette-forming T-lymphocytes. 相似文献
998.
O E Kolesova G V Leont'eva L A Apollonova R Kh Chilingirov Iu I Bobkov 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(3):282-284
The method of intravenous administration of UV-irradiated donor plasma to patients with jaundice of different genesis has been tested in the experiments on rats and used clinically in 20 patients. Biochemical and morphological studies have shown that such treatment causes stable improvement in the liver functional state. 相似文献
999.
L V Antonova A A Kamenski? T I Vlasova N Iu Sarycheva V N Nezavibat'ko 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(11):569-571
Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro (ACTH4-10 analog) at a dose of 0.015 mg/kg failed to alter open field behaviour of rats in the first test series. The peptide abolished amphetamine-induced stimulation of the exploratory and grooming behaviour. Extinction of the rats' exploratory behaviour during second test series in the open field (7 days later) was disturbed when haloperidol or apomorphine were injected before the first test series. When the peptide was administered with haloperidol or apomorphine, the extinction tended to become normal. Heptapeptide failed to change noradrenaline, dopamine or 5-hydroxytryptamine content in the rat forebrain. However, this peptide at a concentration of 10(-4) M moderately diminished tyrosine hydroxylation velocity in the rat striatal or hypothalamic synaptosomes, the effect depending on tyrosine concentration. These data suggest the involvement of catecholaminergic component into the heptapeptide action on the behaviour of rats. 相似文献
1000.
Inducible DNA polymerase I synthesis in a UV hyper-resistant mutant of Escherichia coli 总被引:1,自引:0,他引:1
A mutant of Escherichia coli which is more resistant to shortwave UV light than its wild-type parent strain and which can synthesise DNA polymerase I constitutively has been further analysed. It carries two mutational alleles which are located about 1.5 min apart and cotransducible by P1 with the argH locus. The two mutational alleles have been segregated and their analysis shows that one of them is responsible for UV hyper-resistance whereas the other mutation confers UV sensitivity. Recombinant plasmids carrying various sections of the polA regulatory region, linked to a galK gene, were introduced into the mutant strains. Analysis of galactokinase shows that the enzyme activity in the UV hyper-resistant mutant is increased. The results suggest that the synthesis of DNA polymerase I in E. coli is inducible. 相似文献