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61.
62.
The complete nucleotide sequence of the mitochondrial (mt) genome was determined for specimens of the coral species Montipora
cactus (Bernard 1897) and Anacropora
matthai (Pillai 1973), representing two morphologically distinct genera of the family Acroporidae. These sequences were compared
with the published mt genome sequence for the confamilial species, Acropora tenuis (Dana 1846). The size of the mt genome was 17,887 bp and 17,888 bp for M. cactus and A. matthai. Gene content and organization was found to be very similar among the three Acroporidae mt genomes with a group I intron
occurring in the NADH dehyrogenase 5 (nad5) gene. The intergenic regions were also similar in length among the three corals. The control region located between the
small ribosomal RNA (ms) and the cytochrome oxidase 3 (cox3) gene was significantly smaller in M. cactus and A. matthai (both 627 bp) than in A. tenuis (1086 bp). Only one set of repeated sequences was identified at the 3′-end of the control regions in M. cactus and A. matthai. A lack of the abundant repetitive elements which have been reported for A. tenuis, accounts for the relatively short control regions in M. cactus and A. matthai. Pairwise distances and relative rate analyses of 13 protein coding genes, the group I intron and the largest intergenic
region, igr3, revealed significant differences in the rate of molecular evolution of the mt genome among the three species, with an extremely
slow rate being seen between Montipora and Anacropora. It is concluded that rapid mt genome evolution is taking place in genus Acropora relative to the confamilial genera Montipora and Anacropora although all are within the relatively slow range thought to be typical of Anthozoa. 相似文献
63.
A simple flexible method for separation of proteins by polyacrylamide gel electrophoresis and sequential elution into dialysis bags has been devised. The system was applied to isolation of three glycoproteins from the peritoneal fluid of mice bearing Ehrlich ascites tumor. 相似文献
64.
D. J. Jones 《BMJ (Clinical research ed.)》1992,305(6853):575-577
65.
Major and minor electrophoretic variants of juvenile hormone esterase (JHE) were found in the hemolymph of last instar larvae of Trichoplusia ni, both before and after metamorphic commitment. The average ratios of activity of the two major forms were similar during both last stadium peaks in activity. Immunological analysis showed that the hemolymph concentration of JHE during this stadium paralleled the level of enzymatic activity, and no putative higher molecular weight, inactive forms were detected. Immunological analysis provided the first evidence of relatedness of major and minor forms. After hormonal stimulation, the concentration of the two major forms increased concomitantly and by a similar proportion, suggesting that charge variation, at least for these two major forms, is not a point of hormonal or developmental regulation of JHE. 相似文献
66.
67.
68.
Cell wall residues in yeast protoplast preparations 总被引:5,自引:2,他引:3
Protoplast preparations made from Saccharomyces cerevisiae by prolonged treatment with snail digestive juice contained fibrils and chitinous bud-scar residues from the original cell wall. 相似文献
69.
Actinomycin synthesis in Streptomyces antibioticus. Purification and properties of a 3-hydroxyanthranilate 4-methyltransferase 总被引:1,自引:0,他引:1
A methyltransferase, which utilizes 3-hydroxyanthranilic acid (HAA) as a substrate, has been purified to near homogeneity from 30-36-h mycelium of the bacterium Streptomyces antibioticus. The enzyme was obtained in approximately 20% yield with a purification of 130-fold. Polyacrylamide gel electrophoresis under denaturing conditions indicates that the enzyme is composed of a single subunit with Mr of about 36,000. On chromatography in 0.5 M NaCl, the enzyme displays a molecular weight of about 37,000. The specific activity of the enzyme in S. antibioticus mycelium is maximal between 30 and 36 h following inoculation of galactose/glutamic acid medium and, at those times post-inoculation, the specific activity is essentially the same in extracts of mycelium obtained from cultures grown on glucose rather than galactose as the carbon source. The enzyme activity is stimulated by Na2EDTA (in crude extracts) and by 2-mercaptoethanol and the methyltransferase shows a strong preference for HAA as substrate as compared with a number of HAA analogs. Thin layer chromatography of ethyl acetate extracts of large-scale incubation mixtures confirms that the product of the reaction is 4-methyl-3-hydroxyanthranilic acid. The reaction product was also a substrate for phenoxazinone synthase and was incorporated into actinomycin by S. antibioticus mycelium. Kinetic parameters for the methyltransferase reaction was determined. 相似文献
70.