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91.
Curt Stern 《Molecular & general genetics : MGG》1926,41(1):198-215
Ohne ZusammenfassungDie Arbeit wurde an der Columbia Universitität, New York, ausgeführt; der dortige Aufenthalt war ermöglicht durch ein Reisestipendium des International Education Board, für das auch hier der Dank ausgesprochen sei. 相似文献
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Curt Koßwig 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1930,2(9):263-269
Ohne Zusammenfassung 相似文献
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Dr. Carl Curt Hosseus 《Plant Systematics and Evolution》1912,62(1):15-21
Ohne Zusammenfassung 相似文献
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Jill A. Jablonowski Kiev S. Ly Michael Bogenstaetter Curt A. Dvorak Jamin D. Boggs Lisa K. Dvorak Brian Lord Kirsten L. Miller Curt Mazur Sandy J. Wilson Timothy W. Lovenberg Nicholas I. Carruthers 《Bioorganic & medicinal chemistry letters》2009,19(3):903-907
A novel series of imidazole containing histamine H3 receptor ligands were investigated and found to be potent functional antagonists. After improving the stability of these molecules towards liver microsomes, these compounds were found to have no appreciable affinity for CYP P450s. Subsequent in vivo experiments showed significant brain uptake of (4-chloro-phenyl)-[2-(1-isopropyl-piperidin-4-ylmethoxy)-3-methyl-3H-imidazol-4-yl]-methanone 22. 相似文献
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Zhiqiang?Xia Aibin?ZhanEmail author Yangchun?Gao Lei?Zhang G.?Douglas?Haffner Hugh?J.?MacIsaac 《Biological invasions》2018,20(2):437-447
Management of non-indigenous invasive species (NIS) is challenging owing in part to limitations of early detection and identification. The advent of environmental DNA (eDNA) techniques provides an efficient way to detect NIS when their abundance is extremely low. However, eDNA-based methods often suffer from uncertain detection sensitivity, which requires detailed testing before applying these methods in the field. Here we developed an eDNA tool for early detection of the highly invasive golden mussel, Limnoperna fortunei, based on the mitochondrial cytochrome c oxidase subunit I gene (COI). Further, we tested technical issues, including sampling strategy and detection sensitivity, based on a laboratory experiment. We then applied the method to field samples collected from water bodies in China where this mussel has or is expected to colonize. Results showed that the detection limit varied extensively among our newly developed primer pairs, ranging from 4 × 10?2 to 4 × 10?6 ng of total genomic DNA. Laboratory detection was affected by the availability of eDNA (i.e., both mussel abundance and incubation time). Detection capacity was higher in laboratory samples containing re-suspended matter from the bottom layer versus that collected from the surface. Among 25 field sites, detection was 100% at sites with high mussel abundance and as low as 40% at sites with low abundance when tested using our most sensitive primer pair. Early detection of NIS present at low abundance in nature requires not only sensitive primers, but also an optimized sampling strategy to reduce the occurrence of false negatives. Careful selection and detailed testing of primer pairs ensures effective eDNA-based species detection in surveillance and management programs. 相似文献
99.
Unprecedented 34S‐enrichment of pyrite formed following microbial sulfate reduction in fractured crystalline rocks
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Henrik Drake Martin J. Whitehouse Christine Heim Peter W. Reiners Mikael Tillberg K. Johan Hogmalm Mark Dopson Curt Broman Mats E. Åström 《Geobiology》2018,16(5):556-574
In the deep biosphere, microbial sulfate reduction (MSR) is exploited for energy. Here, we show that, in fractured continental crystalline bedrock in three areas in Sweden, this process produced sulfide that reacted with iron to form pyrite extremely enriched in 34S relative to 32S. As documented by secondary ion mass spectrometry (SIMS) microanalyses, the δ34Spyrite values are up to +132‰V‐CDT and with a total range of 186‰. The lightest δ34Spyrite values (?54‰) suggest very large fractionation during MSR from an initial sulfate with δ34S values (δ34Ssulfate,0) of +14 to +28‰. Fractionation of this magnitude requires a slow MSR rate, a feature we attribute to nutrient and electron donor shortage as well as initial sulfate abundance. The superheavy δ34Spyrite values were produced by Rayleigh fractionation effects in a diminishing sulfate pool. Large volumes of pyrite with superheavy values (+120 ± 15‰) within single fracture intercepts in the boreholes, associated heavy average values up to +75‰ and heavy minimum δ34Spyrite values, suggest isolation of significant amounts of isotopically light sulfide in other parts of the fracture system. Large fracture‐specific δ34Spyrite variability and overall average δ34Spyrite values (+11 to +16‰) lower than the anticipated δ34Ssulfate,0 support this hypothesis. The superheavy pyrite found locally in the borehole intercepts thus represents a late stage in a much larger fracture system undergoing Rayleigh fractionation. Microscale Rb–Sr dating and U/Th–He dating of cogenetic minerals reveal that most pyrite formed in the early Paleozoic era, but crystal overgrowths may be significantly younger. The δ13C values in cogenetic calcite suggest that the superheavy δ34Spyrite values are related to organotrophic MSR, in contrast to findings from marine sediments where superheavy pyrite has been proposed to be linked to anaerobic oxidation of methane. The findings provide new insights into MSR‐related S‐isotope systematics, particularly regarding formation of large fractions of 34S‐rich pyrite. 相似文献
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