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61.
62.
Transgenic plants were regenerated from Cichorium intybus L. hairy roots transformed with genes of tuberculosis antigenes ESAT6 and Ag85B or human interferon alpha2b. The plant regeneration was light-dependent and occurred on the media without growth regulators. The DNA PCR and RT-PCR analyses have shown the presence and expression both selective and target genes in all root lines and regenerated plants.  相似文献   
63.
Based on analysis of gliadin patterns in common wheat cultivars developed at the Research Institute of Agriculture of the Southeast, profile dynamics in gliadin loci has been surveyed for the period of over eight decades. It was shown that long-term breeding of the wheat cultivars involved gradual replacement of alleles characteristic of ancient cultivars for those widely spread in the world, which are probably linked with alleles that currently confer advantage to their carriers. The process of reduction of inter-population genetic diversity in wheat (with special reference to the allele frequency dynamics at gliadin loci) is discussed. This process is responsible for genetic erosion of the species.  相似文献   
64.
To find out stable and effective producers of major protective antigens intended for use as components of cholera chemical vaccine against V. cholerae strains of serogroups O and O139, the comparative analysis of the production of cholera toxin, toxin-coregulated pili (TCP), antigens O1 and O139, polysaccharide capsule and outer membrane protein OmpU in different V. cholerae strains groups O1 and O139 has been made. V. cholerae strain KM68, serogroup O1, has been found capable of the production of antigen O1, serovar Ogawa, protein OmpU at a sufficiently high level and the hyperproduction of cholera toxin and TCP, and thus suitable for use in the manufacture of cholera bivalent vaccine as the source of these antigens. Specially selected alysogenic noncapsular strain KM137 of serogroup O139, characterized by a high and stable level of the biosynthesis of this somatic antigen when grown in both laboratory and production conditions, may serve as the produces of antigen O139.  相似文献   
65.
The authors' studies on the organization and variation of plant genome with the use of molecular markers are briefly reviewed with special emphasis on random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR), sequence characterized amplified region (SCAR), and cleaved amplified polymorphic sequence (CAPS) markers detected with the use of polymerase chain reaction (PCR). These markers have been demonstrated to be promising for identifying cultivars and determining the purity of genetic strains of pea. Genetic relationships between strains, cultivars, and mutants of pea have been studied. The role of molecular markers in molecular genetic mapping and localizing the genes of commercially important characters of pea has been shown. The possibility of the use of molecular markers for studying somaclonal variation and detecting mutagenic factors in plants during long-term spaceflights is considered. The prospects of using DNA markers for understanding the organization and variability of higher plant genomes are discussed.  相似文献   
66.
The degrading action of an aquatic plant-microbial association on the base of Canadian pondweed (Elodea canadensis) and its components (sterilized plant and two periphytonic strains, Pseudomonas fluorescens E1-2.1 and Brevundimonas diminuta E1-3.1) on crude oil, the water-soluble crude oil fraction, and individual test compounds (phenol, toluene, benzene, decalin, and naphthalene) was studied. It was found that the native association had a wider range and higher degree of degrading activity than individual species. Bacterial strains were significantly more active only towards naphthalene. The ability of the sterilized plant to degrade crude oil and phenol was no less than that of microorganisms and much more for toluene. Enzymatic activity towards the pollutants studied was found in E. canadensis exudates and buffer extracts of its cells.  相似文献   
67.
In the article the results of the influence of some types of biological molecules and their specific immune complexes on the volt-amperic characteristics of surface-barrier contact structures with the super thick metal film are presented. Moreover, the possibility to develop on this basis a simple instrumental method for separate registration of initial components and products of their interaction is discussed. It was shown that the volt-amperic characteristics of surface-barrier structures of Ni-Si changed at the deposition of myoglobin and its specific monoclonal antibodies. These structures more essentially reacted to the formed presence of specific immune complex and, in particular, to the direct formation of this complex on the surface at the subsequent use of the initial immune components in comparison with their separate presence. For all investigated types of biological molecules and their specific complexes we found optimal thickness of metal film when changes of volt-amperic characteristics of system achieved maximum level. It was concluded that this electrometrical method was suitable for the express and separation free registration of specific immune complex.  相似文献   
68.
The results of proper investigations received under the cytogenetic examination of 225 persons (control groups, Chernobyl liquidators exposed to different radiation doses, oncogematology patients) had been summarized and analyzed. The conclusion concerning possibilities and limitations of FISH technique usage for retrospective biodosimetry of human radiation exposure has been presented.  相似文献   
69.
Based on the analysis of GenBank nucleotide sequences of the cbbL and cbbM genes, coding for the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPC), the key enzyme of the Calvin cycle, a primer system was designed that allows about 800-bp-long fragments of these genes to be PCR-ampliflied in various photo- and chemotrophic bacteria. The efficiency of the designed primer system in detection of RuBPC genes was demonstrated in PCR with DNA of taxonomically diverse bacteria possessing RuBPC genes with a known primary structure. Nucleotide sequences of RuBPC gene fragments of bacteria belonging to the genera Acidithiobacillus. Ectothiorhodospira, Magnetospirillum, Methylocapsa, Thioalkalispira, Rhodobacter, and Rhodospirillum were determined to be deposited with GenBank and to be translated into amino acid sequences and subjected to phylogenetic analysis.  相似文献   
70.
DNA was found to be cleaved in neutral solutions containing arenes and copper (II) salts. The reaction is comparable in efficiency with the DNA cleavage by such systems as Cu(II)-phenanthroline and Cu(II)-ascorbic acid, but, in contrast to the latter, the system Cu(2+)-arene does not require the presence of an exogenous reducing agent or hydrogen peroxide. The system Cu(2+)-arene does not cleave DNA under anaerobic conditions. Catalase, sodium azide, and bathocuproine, which is a specific chelator of Cu(I), completely inhibit the reaction. The data obtained allow one to suppose that Cu(I) ions, superoxide radical, and singlet oxygen participate in the reaction. It has been shown by the EPR method using spin traps that the reaction proceeds with formation of alkoxyl radicals, which can insert breaks in the DNA molecule. For effective cleavage of DNA in the Cu(II)-o-bromobenzoic acid system, the radicals have to be generated by a specific copper-DNA-o-bromobenzoic acid complex, in which copper ions are most probably coordinated with oxygen atoms of the DNA phosphate groups. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2003, vol. 29, no. 6; see also http://www.maik.ru.  相似文献   
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