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951.
Sidorova A. E. Malyshko E. V. Kotov A. R. Tverdislov V. A. Ustinin M. N. 《Biophysics》2019,64(2):155-166
Biophysics - Based on the theory of the formation of sign-alternating hierarchical structures in macromolecular systems, a quantitative approach was developed to assess the chirality sign of... 相似文献
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953.
Shamsee Zahraa R. Al-Saffar Ali Z. Al-Shanon Ahmed F. Al-Obaidi Jameel R. 《Molecular biology reports》2019,46(1):381-390
Molecular Biology Reports - Lantana camara is an important medicinal plant that contains many active compounds, including pentacyclic triterpenoids, with numerous biological activities. The present... 相似文献
954.
Journal of Mathematical Biology - The Kirkpatrick–Barton model, well known to invasion biologists, is a pair of reaction–diffusion equations for the joint evolution of population... 相似文献
955.
To test life-history theory that body size and sex should influence how animals allocate time to foraging versus reproductive activities, we measured the effects of size and sex on courting success and foraging behaviour of black surfperch Embiotoca jacksoni off Santa Catalina Island, southern California. Observations of focal fish were made while snorkelling, during which the length of each fish (estimated to the nearest cm), total duration of courting encounters and foraging rates were recorded. We made observations during and outside the mating season. Courtship occurred only between pairs and its duration increased with the size of both the male and female. Although males would court females that were smaller or larger than themselves, pairs that were closely matched in size had long courting sessions, whereas those that differed considerably in size courted only briefly. Small fish foraged more than larger fish, both during and outside the mating season. Males and females foraged at similar rates outside of the mating season, but during the mating season males reduced their foraging rates to less than half that seen outside of the mating season, whereas females continued to forage at the same rate. This decrease in foraging rate of males during the mating season was seen in all sizes of males but was proportionally greatest in the largest males. These observations indicate that males trade off time spent on foraging for time spent courting during the mating season, whereas females do not. 相似文献
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958.
Sakhanokho Hamidou F. Babiker Ebrahiem M. Smith Barbara J. Drackett Patricia R. 《Plant Cell, Tissue and Organ Culture》2019,137(3):637-637
Plant Cell, Tissue and Organ Culture (PCTOC) - There were two errors in the original publication: The copyright holder was specified as Springer Nature B.V. The correct information is as follows:... 相似文献
959.
Richard P Auburn Roslin R Russell Bettina Fischer Lisa A Meadows Santiago Sevillano Matilla Steven Russell 《BMC bioinformatics》2006,7(1):102-9
Background
Microarrays were first developed to assess gene expression but are now also used to map protein-binding sites and to assess allelic variation between individuals. Regardless of the intended application, efficient production and appropriate array design are key determinants of experimental success. Inefficient production can make larger-scale studies prohibitively expensive, whereas poor array design makes normalisation and data analysis problematic. 相似文献960.
Non-native brook trout (Salvelinus fontinalis) were eradicated from alpine Bighorn Lake, Alberta, Canada, to test whether strong cascading trophic interactions (CTI) can
occur in oligotrophic, high seston C:P, species-poor lakes. Fishless alpine Pipit Lake was used as a reference ecosystem.
Bighorn Lake zooplankton biomass increased from 0.14:1 relative to Pipit Lake before fish removal began in 1997 to 0.6:1 afterwards
due to an increase in the abundance of adult cyclopoid copepods beginning in 1997 and the reappearance of Daphnia middendorffiana in 1998. Following the reappearance of Daphnia, Bighorn Lake total phytoplankton biomass fell from 64:1 relative to Pipit Lake to 0.9:1. Over the same periods Bighorn Lake:Pipit
Lake chlorophyll-a ratios declined from 2.4:1 to 1.6:1, although the decrease was not statistically significant. Mid-summer Secchi disc depth
in Bighorn Lake increased from 3.1 m before manipulation to 9.2 m, the maximum depth of the lake, in 2001 and 2002. Increased
transparency was most likely due to increased filtration of suspended inorganic particles from the water column by higher
abundances of large zooplankton. Post-manipulation increases in dissolved inorganic nitrogen (DIN), DIN:total dissolved phosphorus
(TDP) ratio and declines in TDP in Bighorn Lake were not attributable to ecosystem manipulation, similar changes were observed
in reference Pipit Lake. We conclude that strong pelagic CTI, expressed as change in total phytoplankton biomass and largely
mediated by Daphnia, can occur in oligotrophic, high seston C:P, species-poor ecosystems. However, strong CTI responses in phytoplankton biomass
may lag trophic manipulation by several years. 相似文献