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991.
Jean Emberlin Siegfried Jaeger Eugenio Dominguez-Vilches Carmen Galan Soldevilla Lene Hodal Paolo Mandrioli Auli Rantio Lehtimäki Mike Savage Frits Th. Spieksma Catherine Bartlett 《Aerobiologia》2000,16(3-4):373-379
Geographical and temporal variations in the start dates of grass pollen seasons are described for selected sites of the European
Pollen Information Service. Daily average grass pollen counts are derived from Network sites in Finland, the Netherlands,
Denmark, United Kingdom, Austria, Italy and Spain, giving a broad longitudinal transect over Western Europe. The study is
part of a larger project that also examines annual and regional variations in the severity, timing of the peak and duration
of the grass pollen seasons. For several sites, data are available for over twenty years enabling long term trends to be discerned.
The analyses show notable contrasts in the progression of the seasons annually with differing lag times occurring between
southern and northern sites in various years depending on the weather conditions. The patterns identified provide some insight
into geographical differences and temporal trends in the incidence of pollinosis. The paper discusses the main difficulties
involved in this type of analysis and notes possibilities for using data from the European Pollen Information service to construct
pan European predictive models for pollen seasons.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
992.
C. Galán M. Jose Fuillerat Paul Comtois Eugenio Dominguez-Vilches 《International journal of biometeorology》1998,41(3):95-100
Daily variations in Cupressaceae pollen counts were analysed, together with climatic variables in the southwest of Spain,
in order to understand the bioclimatic variables affecting Cupressaceae flowering in a Mediterranean climate. The study was
carried out using the Spanish Aerobiology Network recommendations, using a Burkard Hirst-type spore trap. Regression analyses
were applied to the pollen counts of the winter months of 13 consecutive years. The regression analysis applied to each year
indicated that temperature is the most important variable to include in the model. Temperature affected the pollen counts
differently according to the yearly climatic trend. During the coldest years, pollen counts depended on the minimum temperature,
while in the warmest ones they were affected by higher temperatures. However, during the driest years, pollen counts depended
more on the humidity level, while in the wettest years they depended more on the hours of sunshine.
Received: 12 November 1996 / Accepted: 19 August 1997 相似文献
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994.
Silvano Monarca Donatella Feretti Alberto Zanardini Massimo Moretti Milena Villarini Berthold Spiegelhalder Ilaria Zerbini Umberto Gelatti Eugenio Lebbolo 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2001,490(2)
This research was designed to examine the presence of mutagenic/carcinogenic compounds in airborne pollutants in the rubber industry using an integrated chemical/biological approach. Inhalable airborne particulate matter (PM-10: <10 μm) was collected in four rubber factories using a high-volume sampler equipped with a cascade impactor for particle fractionation. The organic extracts of two different fractions (0.5–10 μm and <0.5 μm) were examined for mutagenicity with the Ames test and for in vitro DNA-damaging activity in human leukocytes by single-cell microgel electrophoresis (Comet assay). The extracts were also studied by gas chromatography/mass spectrometry (GC/MS) for polycyclic aromatic hydrocarbon (PAH) content. Nitrosamines in ambient air were sampled on cartridges and analysed by GC with a thermal energy analyser (TEA) detector. Airborne volatile genotoxins were monitored in situ using a clastogenicity plant test (Tradescantia/micronuclei test). The results showed that airborne particulates were mainly very fine (<0.5 μm) and that trace amounts of genotoxic nitrosamines (N-nitrosodimethylamine: 0.10–0.98 μg/m3; N-nitrosomorpholine: 0.77–2.40 μg/m3) and PAH (total PAH: 0.34–11.35 μg/m3) were present in air samples. Some extracts, particularly those obtained from the finest fractions, were mutagenic with the Ames test and genotoxic with the Comet assay. In situ monitoring of volatile mutagens using the Tradescantia/micronuclei test gave positive results in two working environments. The results showed the applicability of this integrated chemical–biological approach for detecting volatile and non-volatile genotoxins and for monitoring genotoxic hazards in the rubber industry. 相似文献
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The structure of horse liver alcohol dehydrogenase 总被引:11,自引:0,他引:11
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1000.
Jobran Chebib Benjamin C. Jackson Eugenio Lpez-Cortegano Diethard Tautz Peter D. Keightley 《Heredity》2021,126(1):107
For over a century, inbred mice have been used in many areas of genetics research to gain insight into the genetic variation underlying traits of interest. The generalizability of any genetic research study in inbred mice is dependent upon all individual mice being genetically identical, which in turn is dependent on the breeding designs of companies that supply inbred mice to researchers. Here, we compare whole-genome sequences from individuals of four commonly used inbred strains that were procured from either the colony nucleus or from a production colony (which can be as many as ten generations removed from the nucleus) of a large commercial breeder, in order to investigate the extent and nature of genetic variation within and between individuals. We found that individuals within strains are not isogenic, and there are differences in the levels of genetic variation that are explained by differences in the genetic distance from the colony nucleus. In addition, we employ a novel approach to mutation rate estimation based on the observed genetic variation and the expected site frequency spectrum at equilibrium, given a fully inbred breeding design. We find that it provides a reasonable per nucleotide mutation rate estimate when mice come from the colony nucleus (~7.9 × 10−9 in C3H/HeN), but substantially inflated estimates when mice come from production colonies.Subject terms: Evolutionary genetics, Evolutionary biology, Inbreeding, Genetic variation, Mutation 相似文献