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921.
922.
Asano N Nishida M Miyauchi M Ikeda K Yamamoto M Kizu H Kameda Y Watson AA Nash RJ Fleet GW 《Phytochemistry》2000,53(3):379-382
Adenophora triphylla var. japonica (Campanulaceae) yielded two new alkaloids, the 6-C-butyl derivative of 2R,5R-bis(hydroxymethyl)-3R,4R-dihydroxypyrrolidine (DMDP) and alpha-1-C-ethyl-fagomine, together with the known alkaloids 1,4-dideoxy-1,4-imino-D-arabinitol, 1-deoxynojirimycin, and 1-deoxymannojirimycin. 6-C-Butyl-DMDP showed inhibitory activity toward almond beta-glucosidase (IC50 = 68 microM), whereas alpha-1-C-ethyl-fagomine inhibited bovine liver beta-galactosidase (IC50 = 29 microM). 相似文献
923.
Simultaneous correction of the alignment and the shortening of the deformed little finger in congenital synostosis of the fourth and fifth metacarpals was accomplished by insertion of a wedge-shaped bone block harvested from the fusion site following transverse osteotomy of the fifth metacarpal. Correction can be performed simply and successfully without morbidity of the donor site when this technique is applied to suitable patients. 相似文献
924.
925.
Kamei S Yajima I Yamamoto H Kobayashi A Makabe KW Yamazaki H Hayashi SI Kunisada T 《Biochemical and biophysical research communications》2000,275(2):503-508
The cDNA for a novel member of the FGFR family, named HrFGFR, was isolated from a Halocynthia roretzi cDNA library prepared at the mid-tailbud stage. This cDNA was 3507b long, and the deduced amino acid sequence contained a motif characteristic of the vertebrate FGFRs. The existence of a single copy of the FGFR homologue gene in H. roretzi was suggested by restriction site analysis of multiple clones. HrFGFR mRNA was expressed strongly in the posterior region in the epidermis from the middle neurula stage. By contrast, Xenopus FGFR homologues are expressed in the anterior region and are known to induce anterior neural formation. A transition of the region expressing FGFR might have induced the more complicated brain or head formation characteristic of vertebrates. 相似文献
926.
Tumor necrosis factor induces resistance of macrophages to Legionella pneumophila infection 总被引:1,自引:0,他引:1
McHugh SL Newton CA Yamamoto Y Klein TW Friedman H 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》2000,224(3):191-196
Legionella pneumophila is an ubiquitous opportunistic intracellular pathogen that replicates readily in thioglycollate-elicited peritoneal macrophages from genetically susceptible A/J mice. Treatment of macrophage cultures in vitro with tumor necrosis factor-alpha (TNF-alpha) induced resistance of the macrophages to infection by Legionella as compared with control macrophages treated with medium alone. Addition of small amounts of monoclonal antibody to TNF-alpha restored susceptibility of the macrophages. Furthermore, antibody to the proinflammatory cytokine interleukin-1 (IL-1) alpha/beta increased resistance, but recombinant IL-1 had little effect. Such decreased susceptibility to Legionella growth in anti-IL-1 antibody-treated cultures corresponded with enhanced levels of TNF-alpha in the supernatants of the treated cells. An antibody to another proinflammatory cytokine with known immunoregulatory properties (i.e., IL-6) had little or no effect on the ability of the macrophages to be infected by Legionella and, furthermore, treatment with recombinant IL-6, similar to recombinant IL-1, did not modify the ability of the cells to be infected in vitro. These results indicate that TNF-alpha is important in controlling L. pneumophila replication, and IL-1 can regulate TNF-alpha levels, affecting susceptibility of macrophages to infection with an intracellular opportunistic pathogen like Legionella. 相似文献
927.
928.
Balance of Activities of Alcohol Acetyltransferase and Esterase in Saccharomyces cerevisiae Is Important for Production of Isoamyl Acetate 总被引:2,自引:0,他引:2
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Kiyoshi Fukuda Nagi Yamamoto Yoshifumi Kiyokawa Toshiyasu Yanagiuchi Yoshinori Wakai Katsuhiko Kitamoto Yoshiharu Inoue Akira Kimura 《Applied microbiology》1998,64(10):4076-4078
Isoamyl acetate is synthesized from isoamyl alcohol and acetyl coenzyme A by alcohol acetyltransferase (AATFase) in Saccharomyces cerevisiae and is hydrolyzed by esterases at the same time. We hypothesized that the balance of both enzyme activities was important for optimum production of isoamyl acetate in sake brewing. To test this hypothesis, we constructed yeast strains with different numbers of copies of the AATFase gene (ATF1) and the isoamyl acetate-hydrolyzing esterase gene (IAH1) and used these strains in small-scale sake brewing. Fermentation profiles as well as components of the resulting sake were largely alike; however, the amount of isoamyl acetate in the sake increased with an increasing ratio of AATFase/Iah1p esterase activity. Therefore, we conclude that the balance of these two enzyme activities is important for isoamyl acetate accumulation in sake mash. 相似文献
929.
Fabrication of a new substrate for atomic force microscopic observation of DNA molecules from an ultrasmooth sapphire plate.
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K Yoshida M Yoshimoto K Sasaki T Ohnishi T Ushiki J Hitomi S Yamamoto M Sigeno 《Biophysical journal》1998,74(4):1654-1657
A new stable substrate applicable to the observation of DNA molecules by atomic force microscopy (AFM) was fabricated from a ultrasmooth sapphire (alpha-Al2O3 single crystal) plate. The atomically ultrasmooth sapphire as obtained by high-temperature annealing has hydrophobic surfaces and could not be used for the AFM observation of DNA. However, sapphire treated with Na3PO4 aqueous solution exhibited a hydrophilic character while maintaining a smooth surface structure. The surface of the wet-treated sapphire was found by x-ray photoelectron spectroscopy and AFM to be approximately 0.3 nm. The hydrophilic surface character of the ultrasmooth sapphire plate made it easy for DNA molecules to adhere to the plate. Circular molecules of the plasmid DNA could be imaged by AFM on the hydrophilic ultrasmooth sapphire plate. 相似文献
930.
A clear parallelism was demonstrated between the efficiency as substrate of the substituted oligopeptides corresponding to the carboxy-terminal (C-terminal) sequence of the precursor D1 protein (pD1) in the in vitro enzymatic assay and their competitive inhibitory capacity toward the proteolytic C-terminal processing of the full-length pD1 integrated in the intact photosystem II complex embedded in the thylakoid membrane of Scenedesmus obliquus LF-1 mutant, as shown e.g. by the influence of L343A, A345G and A345V substitutions and the effect of C-terminal fragments. This suggests that the basic mechanism for substrate recognition by the processing protease elucidated in the enzymatic analysis using synthetic oligopeptides is also effective in vivo, although it can sometimes be difficult to detect the consequence of amino acid substitution in the integrated systems. 相似文献