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1.
T M Makarova E I Varlinskaia T I Chasovnikova E S Petrov 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1991,41(6):1231-1238
It is shown, that rats, bred in conditions of intraspecies isolation are able to competition for water in the kin group, having usual experience of intraspecies intercourse. At the same level of drinking motivation in conditions of competition for water the intraspecies activity is significantly higher in rats, bred in isolation in comparison with grouped animals. Rats-isolants significantly more often than the grouped animals use extraordinary tactics of intraspecies behaviour, which increase their competitive ability in conditions of limited access to water. 相似文献
2.
The exudation, composition, and biological activity of the phenolic compounds (PC) of pea (Pisum sativum L.) roots in the light and darkness were studied. The roots of leguminous plants grown for 5 days in darkness exuded a smaller amount of PC that displayed a weaker stimulation of Rhizobium reproduction. Moreover, the root exudates contained antimicrobial compounds, stilbenes. It is assumed that a lower PC exudation by roots and the specific features of PC composition influencing the biological activity are among the reasons causing a delayed nodulation of legumes grown in darkness. 相似文献
3.
Makarova EN Bazhan NM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1999,85(8):1109-1115
The HPA axis function and the fat metabolism were studied in adult male water voles born to intact mothers and mothers deprived of food on the 15th and 18th days of their pregnancy. The HPA response to emotional stress was relatively low in experimental males in winter. The hormonal response to a 24-hrs food deprivation diminished in experimental group only in February. The blood level of free fatty acids was increased in experimental group as compared to the control one. The short maternal food deprivation modified adaptive abilities of their male progeny. 相似文献
4.
Neronova EG Nikiforov AM Slozina NM Zybina NN Makarova NV Timofeeva MN 《Tsitologiia》2004,46(6):561-566
This investigation was performed to test a supposition about the influence of disturbances in antioxidative system on cytogenetical parameters in Chernobyl' clean-up workers. It was shown that some cytogenetical parameters straightly correlated with the parameters of oxidative stress, while other cytogenetical parameters show just reverse correlations. Apparently, these relationships are not of cause-and-effect type, but they reflect a complex processes occurring in humans for a long period after radiation exposure. 相似文献
5.
6.
V A Makarova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1978,(4):112-116
The authors present data concerning the study of the antigenic properties of rickettisa of the tick-borne spotted fever group isolated from the Ixodes ticks in the Armenain SSR. In order to determine the species of the isolated strains a method of serological identification of rickettsia in the complement fixation reaction with the species-specific immune sera of albino mice was used. The results obtained permitted to refer the Armenia-74, No. 11, 29, and 57 species to the R. sibricia species. 相似文献
7.
8.
Makarova OV Viktorova TV Ianbaeva DG Korytina GF Iakupova EV Karimova LK 《Genetika》2003,39(9):1268-1274
Genetic polymorphism of xenobiotic metabolizing enzymes responsible for individual susceptibility to different environmental factors was examined in a cohort of petrochemical workers occupationally exposed to adverse action of chemical compounds. Molecular genetic analysis of the 1462V mutation in exon 17 of the CYP1A gene demonstrated close similarity between the genotype and allele frequency distribution patterns in the industrial and control groups. No association between the CYP1A polymorphic alleles and genotypes and the duration of service and concomitant diseases was observed. The odds ratio of the disease development in the workers carrying heterozygous CYP1A1 mutant allele was 2.2. Analysis of the STM1 gene polymorphism demonstrated a decrease in the frequency of the homozygous deletion carriers in the workers compared to the control group. There were no substantial differences between the industrial and control groups with respect to the frequencies of rapid and slow acetylator genotypes revealed at the analysis of the NAT2 gene polymorphism. However, considering the concomitant diseases, in the corresponding industrial subgroup a clear trend towards lower frequency of rapid acetylators was demonstrated. In addition, the odds ratio of the disease development for the workers with slow acetylator phenotype was 1.7. 相似文献
9.
Venkateswaran A McFarlan SC Ghosal D Minton KW Vasilenko A Makarova K Wackett LP Daly MJ 《Applied and environmental microbiology》2000,66(6):2620-2626
Immense volumes of radioactive wastes, which were generated during nuclear weapons production, were disposed of directly in the ground during the Cold War, a period when national security priorities often surmounted concerns over the environment. The bacterium Deinococcus radiodurans is the most radiation-resistant organism known and is currently being engineered for remediation of the toxic metal and organic components of these environmental wastes. Understanding the biotic potential of D. radiodurans and its global physiological integrity in nutritionally restricted radioactive environments is important in development of this organism for in situ bioremediation. We have previously shown that D. radiodurans can grow on rich medium in the presence of continuous radiation (6,000 rads/h) without lethality. In this study we developed a chemically defined minimal medium that can be used to analyze growth of this organism in the presence and in the absence of continuous radiation; whereas cell growth was not affected in the absence of radiation, cells did not grow and were killed in the presence of continuous radiation. Under nutrient-limiting conditions, DNA repair was found to be limited by the metabolic capabilities of D. radiodurans and not by any nutritionally induced defect in genetic repair. The results of our growth studies and analysis of the complete D. radiodurans genomic sequence support the hypothesis that there are several defects in D. radiodurans global metabolic regulation that limit carbon, nitrogen, and DNA metabolism. We identified key nutritional constituents that restore growth of D. radiodurans in nutritionally limiting radioactive environments. 相似文献
10.
Connected gene neighborhoods in prokaryotic genomes 总被引:11,自引:1,他引:11
Rogozin IB Makarova KS Murvai J Czabarka E Wolf YI Tatusov RL Szekely LA Koonin EV 《Nucleic acids research》2002,30(10):2212-2223
A computational method was developed for delineating connected gene neighborhoods in bacterial and archaeal genomes. These gene neighborhoods are not typically present, in their entirety, in any single genome, but are held together by overlapping, partially conserved gene arrays. The procedure was applied to comparing the orders of orthologous genes, which were extracted from the database of Clusters of Orthologous Groups of proteins (COGs), in 31 prokaryotic genomes and resulted in the identification of 188 clusters of gene arrays, which included 1001 of 2890 COGs. These clusters were projected onto actual genomes to produce extended neighborhoods including additional genes, which are adjacent to the genes from the clusters and are transcribed in the same direction, which resulted in a total of 2387 COGs being included in the neighborhoods. Most of the neighborhoods consist predominantly of genes united by a coherent functional theme, but also include a minority of genes without an obvious functional connection to the main theme. We hypothesize that although some of the latter genes might have unsuspected roles, others are maintained within gene arrays because of the advantage of expression at a level that is typical of the given neighborhood. We designate this phenomenon ‘genomic hitchhiking’. The largest neighborhood includes 79 genes (COGs) and consists of overlapping, rearranged ribosomal protein superoperons; apparent genome hitchhiking is particularly typical of this neighborhood and other neighborhoods that consist of genes coding for translation machinery components. Several neighborhoods involve previously undetected connections between genes, allowing new functional predictions. Gene neighborhoods appear to evolve via complex rearrangement, with different combinations of genes from a neighborhood fixed in different lineages. 相似文献