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Summary A severely retarded, dystrophic, hypotonic boy with joint hyperflexibility, jaw anomalies, cerebral hypoplasia and failure to thrive is reported. He died at the age of 8 months. Clinical and biochemical investigation revealed predominantly normal values. An unusual type of palmar crease was found. Chromosomal studies showed a translocation, probably a mosaic with normal cells. The parents are chromosomally normal. 相似文献
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374.
Martin Konvicka Kamil Zimmermann Martina Klimova Vladimir Hula Zdenek Fric 《Population Ecology》2012,54(1):91-101
A pertinent question in animal population ecology is the relationship between population abundance, density, and mobility.
Two extreme ways to reach sufficient abundance for long-term persistence are to inhabit restricted locations at high densities,
or large areas in low densities. The former case predicts low individual mobility, whereas the later predicts high one. This
assumption is rarely tested using across-species comparisons, due to scarcity of data on both mobility and population sizes
for multiple species. We used data on dispersal and local population densities of six butterfly species gained by mark-recapture,
and data on their (relative) regional abundance obtained by walking transects in a landscape surrounding the mark-recapture
sites. We correlated both local density and regional abundance against slopes of the inverse power function, appropriate for
describing the shape of dispersal kernel. Local densities correlated negatively with the dispersal kernel slopes both when
sexes were treated as independent data points and if treated together. For regional abundance, the correlation was also negative
but only marginally significant. Our results corroborate the notion that a trade-off exists between living in dense populations
and having poor dispersal, and vice versa. We link this observation to resource use by individual species, and distribution
of such resources as host plants in the study landscape. 相似文献
375.
Libor Necas Zoltan Cibula Jiri Behounek Jr. Stanislav Krivanek Zdenek Horak 《Computer methods in biomechanics and biomedical engineering》2017,20(12):1364-1372
The study was aimed at the clinical and biomechanical analyses of the sliding hip screw breakage with the use of finite element method. We have identified two patients with the sliding screw breakage. In the first patient, the biomechanical analysis revealed the reduced stress values σHMH not exceeding the yield limit or strength limit of the implant. The yield limit was exceeded in second one. Clinical and biomechanical analyses have demonstrated that adherence to technical requirements of the appropriate osteosynthesis implementation is the principal condition of timely healing since it prevents the material failure. 相似文献
376.
The ability to identify individuals within a population is often essential for a detailed understanding of the ecology and conservation of a species. However, some species, including large parrots, are notoriously difficult to catch and mark for individual identification. Palm cockatoos (Probosciger aterrimus) are a large, poorly understood species of parrot which are likely in severe decline within the eastern part – and possibly the western part – of their range on Cape York Peninsula, Australia. Here, we investigated whether three different palm cockatoo call types are sufficiently individually distinctive to function as a non-invasive “marker” for identifying individuals over time. Using Discriminant Function Analysis, overall identification accuracy among 12 putative individuals for all call types was 81% (i.e. 148 out of 183 calls were assigned to the correct individual) on the basis of multiple temporal, energy (amplitude) and frequency measurements on the spectrogram. For three different call types, individual identification accuracy among males and females ranged from 69 to 95%. However, based on a limited sample sizes of five putative individuals between years, our data suggest that individual call structure, as quantified by call parameters, was not stable between years. We discuss the applicability of these results for future studies of palm cockatoos and other parrot species. 相似文献
377.