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991.
Social scientists have not integrated relevant knowledge from the biological sciences into their explanations of human behavior. This failure is due to a longstanding antireductionistic bias against the natural sciences, which follows on a commitment to the view that social facts must be explained by social laws. This belief has led many social scientists into the error of reifying abstract analytical constructs into entities that possess powers of agency. It has also led to a false nature-culture dichotomy that effectively undermines the place of biology in social scientific explanation. Following the principles of methodological individualism, we show how behavioral explanations supported by data and theory from the neurosciences can be used to correct the errors of reificationist thinking in the social sciences. We outline a mechanistic approach to the explanation of human behavior with the hope that the biological sciences will begin to find greater acceptance among social scientists. 相似文献
992.
993.
994.
Chromosomal DNA from three individuals with familial hemoglobin M (Hb M) Milwaukee was studied by restriction endonuclease analysis. The segregation of the mutant beta-globin gene could be followed through three generations by direct Sst I analysis at the gene level. Various restriction endonucleases were used to confirm the positions of Sst I sites in the delta-beta A- and delta-beta Mi-globin gene regions. 相似文献
995.
Horst Schmieger 《Molecular & general genetics : MGG》1982,187(3):516-518
Summary Numbers of transducing particles for a set of 28 different chromosomal markers were determined in a lysate of Salmonella phage P22. The results were plotted with regard to the map positions of the transduced loci. Maxima of the resulting curve are interpreted as positions of start signals (pac-sites) for packaging series on the Salmonella chromosome. 5–6 pac-sites could be found as a minimum estimate. 相似文献
996.
Barbara Kufer Horst Backhaus Horst Schmieger 《Molecular & general genetics : MGG》1982,187(3):510-515
Summary P22 lysates were grown on Salmonella strains carrying P22 prophages deleted to various extents. Transducing bacterial markers at both sides of the prophage insertion site it could be shown that: (i) transduction of markers can be enhanced by the prophage pac site; (ii) the recognition signal pac is in the area of gene 3 on the phage genome and thus close to the cutting site(s); (iii) transposon Tn10 may also act as a signal for packaging initiation; (iv) (at least) Tn10 initiates packaging sequences in both directions. 相似文献
997.
Summary Optimal growth conditions for Zymomonas mobilis have been established using continuous cultivation methods. Optimal substrate utilization efficiency occurs with 2.5 g l–1 yeast extract, 2.0 g l–1 ammonium sulfate and 6.0 g l–1 magnesium sulfate in the media. Catabolic activity is at its maximum with glucose uptake rates of 16–18 g l–1 h–1 and ethanol production rates of 8–9 g l–1 h–1, Qg values of 22–26 and Qp values between 11 and 13, which results in 40 g l–1 h–1 ethanol yields using a 100 g l–1 substrate feed. Any increase in these parameters goes on cost of substrate utilization efficiency. Calcium pantothenate can not substitute yeast extract.Abbreviations G
Glucose (%)
- Pant
Calcium pantothenate (mg l–1)
- D
Dilution rate (h–1)
- NH4
Ammonium sulfate (%)
- Mg
Magnesium sulfate (%)
- S1
Residual glucose in the fermenter (g l–1)
- S0
Glucose feed (g l–1)
- Eth
Ethanol concentration (g l–1)
- GUR
Glucose uptake rate (g l–1 h–1)
- Qg
Specific glucose uptake rate (g g–1 h–1)
- Qp
Specific ethanol production rate (g g–1 h–1)
- EPR
Ethanol production rate (g l–1 h–1)
- Yg
Yield coefficient for glucose (g g–1)
- Yp
Conversion efficiency (%)
- C
Biomass concentration (g l–1)
Present address: (Until June 1982) Institut für Mikrobiologie, TH Darmstadt, 6100 Darmstdt, Federal Republic of Germany 相似文献
998.
23, 25, 26-trihydroxycholecalciferol. A 25-hydroxycholecalciferol-26,23-lactone precursor. 总被引:1,自引:1,他引:0 下载免费PDF全文
(23S)-23,25-Dihydroxycholecalciferol was converted into at least five metabolites in kidney homogenates prepared from 1,25-dihydroxycholecalciferol-treated chickens. One of these has been positively identified as 23,25,26-trihydroxycholecalciferol by u.v.-absorbance analysis, mass spectrometry and chemical formation of derivatives. 23,25,26-Trihydroxycholecaciferol produces 25-hydroxycholecalciferol-26,23-lactone when incubated in chick kidney homogenates. 相似文献
999.
Pál Maliga Horst Lörz Gabriella Lázár Ferenc Nagy 《Molecular & general genetics : MGG》1982,185(2):211-215
Summary Protoplasts of Nicotiana tabacum (SR1), carrying a maternally-inherited streptomycin resistance mutation, were enucleated by centrifugation through a Percoll gradient. The resulting cytoplasts containing resistant plastids, were fused with sensitive Nicotiana plumbaginifolia protoplasts. The SR1 cytoplasts, having no nuclei, were unable to form calli. All resistant clones recovered after fusion-induction were therefore supposed to be derived from interspecific cytoplast-protoplast fusion.
N. plumbaginifolia plants regenerated in 17 out of the 75 resistant clones studied. Plants obtained from eight of these clones were resistant to streptomycin and inherited the resistance maternally, as expected when transferring SR1 plastids into the N. plumbaginifolia nuclear background. Plastid transfer in these plants has been confirmed by the EcoRI restriction pattern of the chloroplast DNA.In nine clones N. plumbaginifolia plants were sensitive although obtained from initially resistant clones. This phenomenon is explained by the maintenance of plastid heterogeneity on the selective streptomycin medium, and formation of plants from sensitive sectors on the non-selective regeneration medium.SR1 protoplasts, originally present as contaminants in the cytoplast preparation (2–7%) did not form colonies (or very rarely) after polyethylene glycol treatment. The nuclei from such protoplasts were recovered, however, in the interspecific somatic hybrids (56 clones), and in segregants having the SR1 nucleus but some cytoplasm from N. plumbaginifolia (2 clones). The majority (about 80%) of the recovered resistant clones therefore acquired the streptomycin resistance factor from the rare (2–7%) contaminating SR1 protoplasts. This is explained by the protoplasts being more stable during fusion induction. 相似文献
1000.
Summary By using recombinant DNA techniques, we have constructed a chimeric plasmid, pSM7322 (10.8 kb), between the streptococcal erythromycin resistance vector plasmid pSM7 (6.4 kb) and the E. coli vector pBR322 (4.4 kb). As judged by the minimum inhibitory concentrations of erythromycin and lincomycin, pSM7-determined resistance to these antibiotics is expressed in E. coli. 相似文献