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81.
P. Nielsen R. Fischer H. C. Heinrich A. A. Pfau 《Cellular and molecular life sciences : CMLS》1988,44(6):502-504
Summary The efficacy of different hexacyanoferrates(II) in preventing the enteral absorption of134Cs was studied in piglets. As compared to the controls, oral application of134Cs together with KFe[Fe(CN)6], NH4Fe[Fe(CN)6], or Fe4[Fe(CN)6]3 resulted in a strong reduction of the134Cs-uptake by more than 97%. The decrease in enteral absorption depends on the dose of administered hexacyanoferrate(II), whereas differences between the compounds under study were small. The biological half-life of134Cs in non-hexacyanoferrate(II) treated piglets was 21.6±3.3 days (mean±SD). 相似文献
82.
Allgén L. -G. Jönsson B. Nauckhoff B. Andersen M. -L. Huus I. Møller Nielsen I. 《Cellular and molecular life sciences : CMLS》1960,16(7):325-325
Zusammenfassung Die Ausscheidung des neuen Neuroleptikums, Chlorprothixen, bei Menschen und Ratten wurde in Urin, Galle und Faeces untersucht und als einziges Abbauprodukt Chlorprothixen-Sulfoxyd gefunden. Ausscheidungsprodukte in % der verabreichten Dosis: Beim Menschen (orale Verabreichung) im Urin: 5–29% Sulfoxyd, Faeces: 0–41% unveränderter Stoff + Sulfoxyd. Bei der Ratte (orale oder parenterale Verabreichung) im Urin: bis zu 5% Sulfoxyd, Faeces: 1–7% Sulfoxyd, keine unveränderte Substanz, Galle: bis zu 24% Sulfoxyd. 相似文献
83.
Upwelling-driven nearshore hypoxia signals ecosystem and oceanographic changes in the northeast Pacific 总被引:2,自引:0,他引:2
Grantham BA Chan F Nielsen KJ Fox DS Barth JA Huyer A Lubchenco J Menge BA 《Nature》2004,429(6993):749-754
Seasonal development of dissolved-oxygen deficits (hypoxia) represents an acute system-level perturbation to ecological dynamics and fishery sustainability in coastal ecosystems around the globe. Whereas anthropogenic nutrient loading has increased the frequency and severity of hypoxia in estuaries and semi-enclosed seas, the occurrence of hypoxia in open-coast upwelling systems reflects ocean conditions that control the delivery of oxygen-poor and nutrient-rich deep water onto continental shelves. Upwelling systems support a large proportion of the world's fisheries, therefore understanding the links between changes in ocean climate, upwelling-driven hypoxia and ecological perturbations is critical. Here we report on the unprecedented development of severe inner-shelf (<70 m) hypoxia and resultant mass die-offs of fish and invertebrates within the California Current System. In 2002, cross-shelf transects revealed the development of abnormally low dissolved-oxygen levels as a response to anomalously strong flow of subarctic water into the California Current System. Our findings highlight the sensitivity of inner-shelf ecosystems to variation in ocean conditions, and the potential impacts of climate change on marine communities. 相似文献
84.
Lesion of the bone matrix in vitamin D-resistant rickets 总被引:2,自引:0,他引:2
85.
Summary The insecticide 4-methylthio-1,2-dithiolane, named charatoxin, blocks the frog muscular twitches elicited through the neuromuscular junction. The activity level and the course of inhibition is comparable to that of 4-dimethyl-amino-1,2-dithiolane, nereistoxin.The authors are grateful to Dr N. Jacobsen, Cheminova A/S for synthesizing the toxins and the 2 analogues. 相似文献
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88.
Lohmueller KE Indap AR Schmidt S Boyko AR Hernandez RD Hubisz MJ Sninsky JJ White TJ Sunyaev SR Nielsen R Clark AG Bustamante CD 《Nature》2008,451(7181):994-997
Quantifying the number of deleterious mutations per diploid human genome is of crucial concern to both evolutionary and medical geneticists. Here we combine genome-wide polymorphism data from PCR-based exon resequencing, comparative genomic data across mammalian species, and protein structure predictions to estimate the number of functionally consequential single-nucleotide polymorphisms (SNPs) carried by each of 15 African American (AA) and 20 European American (EA) individuals. We find that AAs show significantly higher levels of nucleotide heterozygosity than do EAs for all categories of functional SNPs considered, including synonymous, non-synonymous, predicted 'benign', predicted 'possibly damaging' and predicted 'probably damaging' SNPs. This result is wholly consistent with previous work showing higher overall levels of nucleotide variation in African populations than in Europeans. EA individuals, in contrast, have significantly more genotypes homozygous for the derived allele at synonymous and non-synonymous SNPs and for the damaging allele at 'probably damaging' SNPs than AAs do. For SNPs segregating only in one population or the other, the proportion of non-synonymous SNPs is significantly higher in the EA sample (55.4%) than in the AA sample (47.0%; P < 2.3 x 10(-37)). We observe a similar proportional excess of SNPs that are inferred to be 'probably damaging' (15.9% in EA; 12.1% in AA; P < 3.3 x 10(-11)). Using extensive simulations, we show that this excess proportion of segregating damaging alleles in Europeans is probably a consequence of a bottleneck that Europeans experienced at about the time of the migration out of Africa. 相似文献