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291.
Silje Skeide Fuglerud Reinold Ellingsen Astrid Aksnes Dag Roar Hjelme 《Journal of biophotonics》2021,14(5):e202000450
Near infrared spectroscopy (NIR) is a promising technique for continuous blood glucose monitoring for diabetic patients. Four interferents, at physiological concentrations, were introduced to study how the glucose predictions varied with a standard multivariate calibration model. Lactate and ethanol were found to interfere strongly with the glucose predictions unless they were included in the calibration models. Lactate was mistaken for glucose and gave erroneously high glucose predictions, with a dose response of 0.46 mM/mM. The presence of ethanol resulted in too low glucose predictions, with a dose response of −0.43 mM/mM. Acetaminophen, a known interferent in the glucose monitoring devices used for diabetes management today, was not found to be an interferent in NIR spectroscopy, nor was caffeine. Thus, interferents that may appear in high concentrations, such as ethanol and lactate, must be included in the calibration or model building of future NIR-based glucose measurement devices for diabetes monitoring. 相似文献
292.
This study aims at assessing the suitability of Hylocomium splendens as a biomonitor for heavy metal deposition and contributing
to the understanding of mineral nutrient uptake mechanisms in forest floor bryophytes. Concentrations of Ca, Mg, K, Cd, Cu
and Pb were determined in Hylocomium splendens segment samples collected at 196 permanent vegetation plots from eleven monitoring
areas, where the vegetation-environment relationships had previously been thoroughly studied. Element concentrations in Hylocomium
splendens were related to environmentally interpreted vegetational gradients, cover of understorey vascular plants, and local
environmental conditions, including element concentrations in humus, soil moisture and tree impact, by means of correlation
analyses performed separately for each area. A combined test was performed for each Hylocomium splendens variable over all
eleven areas, showing that concentrations of Ca, Cd and Mg in Hylocomium splendens were strongly correlated with the main
vegetational gradient and with pH and concentrations of Ca and total N in humus, indicating considerable uptake of nutrients
by Hylocomium splendens from water that has been in contact with humus. These relationships were less strong in the climatically
most humid areas. Concentrations of all elements were more or less strongly correlated with one or more variables reflecting
tree influence (tree density as measured by basal area and two crown influence indices) reflecting that throughfall precipitation,
modified by leaching from the canopy, partly accounts for input of elements, especially for K, Cd and Mg. Only concentrations
of Pb, Cd and Cu were significantly correlated, negatively, with vascular plant cover, indicating that supply of elements
by leaching from understorey vascular plant foliage is negligible. The concentration of Cu in Hylocomium splendens was only
weakly correlated, and the concentration of Pb unrelated to vegetational gradients and most environmental conditions. The
results indicate that atmospheric deposition accounts for most of the input of Pb, confirming the suitability of Hylocomium
splendens as a biomonitor for this element. For elements such as Cd local environmental conditions should be carefully considered,
even when data from regional moss surveys are to be interpreted.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
293.
Littoral microcrustaceans (Cladocera and Copepoda) as indices of recovery of a limed water system 总被引:1,自引:0,他引:1
A 7 year study (1992–1998) of littoral microcrustaceans (Cladocera and Copepoda) in the watercourse of the River Rore, South Norway, illustrates that qualitative data on cladocerans and copepods are well suited to indicate the recovery of lakes following liming. Eight limed, two acid and two circum neutral reference lakes, were sampled twice a year (June/July and September/October). In the limed lakes, species associated with neutral lakes have become more common, whereas apparently acid-tolerant species have become rarer. In Lake Rore and Lake Syndle, the two largest limed lakes which exhibited a gradual increase in pH, the changes in species composition indicated that these lakes were about to recover. Species composition in Lake Røynelandsvatn, which has reacidified after liming, first reflected improved water quality, then reverted to dominance by acid-tolerant species. In the remaining lakes, the species composition reflects a fauna which has recovered compared with the preliming situation. There is strong evidence, however, that temporary fluctuations in pH have a negative influence on the speed of recovery, confirming the importance of keeping pH stable. 相似文献
294.