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771.
Maija K. Pietilä Nina S. Atanasova Hanna M. Oksanen Dennis H. Bamford 《Environmental microbiology》2013,15(6):1674-1686
Extremophiles are found in all three domains of cellular life. However, hyperthermic and hypersaline environments are typically dominated by archaeal cells which also hold the records for the highest growth temperature and are able to grow even at saturated salinity. Hypersaline environments are rich of virus‐like particles, and spindle‐shaped virions resembling lemons are one of the most abundant virus morphotypes. Spindle‐shaped viruses are archaea‐specific as all the about 15 such virus isolates infect either hyperthermophilic or halophilic archaea. In the present work, we studied spindle‐shaped virus His1 infecting an extremely halophilic euryarchaeon, Haloarcula hispanica. We demonstrate that His1 tolerates a variety of salinities, even lower than that of seawater. The detailed analysis of the structural constituents showed that the His1 virion is composed of only one major and a few minor structural proteins. There is no lipid bilayer in the His1 virion but the major structural protein VP21 is most likely lipid modified. VP21 forms the virion capsid, and the lipid modification probably enables hydrophobic interactions leading to the flexible nature of the virion. Furthermore, we propose that euryarchaeal virus His1 may be related to crenarchaeal fuselloviruses, and that the short‐tailed spindle‐shaped viruses could form a structure‐based viral lineage. 相似文献
772.
Janne Atosuo Outi Karhuvaara Eetu Suominen Liisa Viln Jari Nuutila Tuula Putus 《Innate immunity》2021,27(1):15
In this comparative study, serum complement system antimicrobial activity was measured from 159 serum samples, taken from individuals from microbe-damaged (70 samples) and from reference buildings (89 samples). Antimicrobial activity was assessed using a probe-based bacterial Escherichia coli-lux bioluminescence system and comparison was made at a group level between the experimental and reference group. The complement activity was higher in users of microbe-damaged buildings compared with the reference group and the significant (P < 0.001) increase in activity was found in the classical reaction pathway. This study strengthens our notion that exposure to indoor-related microbe damage increases the risk for systemic subclinical inflammation and creates a health risk for building users. 相似文献
773.
Three different synthetic strategies were tested to synthesize EGFRvIII peptide (1), which is a functional variant of the epidermal growth factor receptor, a protein that has been well validated as a target for cancer therapy. The initial synthesis was performed with Applied Biosystem (Carlsbad, CA, USA) 433A peptide synthesizer and it indicated that the last three amino acids coupling and Fmoc removal rates were lower than the rest of the sequence. Purity of the crude peptide was 54.5%. The second synthesis was performed manually utilizing C S Bio (Menlo Park, CA, USA) synthesizer and the Kaiser test for reaction monitoring. Because of non‐optimized reaction conditions and an unexpected by‐product, lower purity crude peptide (40.5%) was obtained. Quantitative assays to monitor reactions were developed and demonstrated in gram scale synthesis with C S Bio synthesizer. The optimized synthetic conditions improved the peptide purity to 68.1%. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
774.
Little Ice Age Farming in Finland: Preindustrial Agriculture on the Edge of the Grim Reaper’s Scythe
This study examines potential climatic influences on historical agrarian populations in Finland by means of historical weather
diaries, rye phenology, and rye and barley grain-figure (ratio between sown and harvested grain) data from the sixteenth to
the nineteenth centuries. Crops exhibited great temporal variation. During the poorest years, the amount of harvested grain
was less than that sown whereas during the better years the sown grain was harvested more than tenfold. Depending on the locality,
37–84% of this variability could be explained by monthly variables of growing season temperature and precipitation over the
latter half of the eighteenth century. Although the grain-figure data showed clear spatial synchrony, it was found that this
synchrony was much weaker than that of temperature, precipitation or rye phenology. Consequently, individual crop failure
years should not be extrapolated over widely extended areas from spatially restricted data. Further, it was found that the
desertion of farms in the sixteenth and the seventeenth centuries occurred coterminously with long-term summer temperature
cooling, indicating that the desertion may have resulted from climatic deterioration that significantly impeded agriculture
as a means of subsistence. 相似文献
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Jari Nieppola 《植被学杂志》1992,3(4):475-484
Abstract. Understorey vegetation dynamics in Pinus sylvestris L. stands were examined over 30 yr in southern Finland. Data were collected from 112 permanent sample plots twice, first in 1950–1956 and again in 1983 - 1986. Between the two surveys 52 stands were clear-felled and in the 60 remaining old stands thinnings of various magnitude were conducted. In the mature, thinned stands species presence remained virtually unchanged. With the exception of a few species, including Vaccinium vitis-idaea, Hylocomium splendens, and Dicranum polysetum, the changes in species cover were also slight. In the clear-felled plots the changes in species presence were minor but the cover of many species changed strongly. The average cover of Vaccinium myrtillus and Hylocomium splendens dropped to near zero and that of Vaccinium vitisidaea and Pleurozium schreberi decreased 2 - 4 times on all sites. The cover of Calluna vulgaris approximately doubled, and Cladina rangiferina and Cladina arbuscula also increased after canopy removal. In addition to intrinsic successional change, a special interest in this study was to investigate vegetation dynamics in relation to forest land classification methods in which understorey vegetation is used as part of the classification criteria. The results support the Cajanderian site classification approach, in the case of boreal Scots pine stands, that sites can be classified on the basis of understorey vegetation at different successional phases. However, because of the strong successional and site-to-site variation in species cover, it is suggested that site classification be based primarily on species presence 相似文献
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Guo-Feng Ma Simo Miettinen Pauliina Porola Klaus Hedman Jari Salo Yrjö T Konttinen 《BMC microbiology》2009,9(1):55-7