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Viktor Dremin Igor Kozlov Mikhail Volkov Nikita Margaryants Andrey Potemkin Evgeny Zherebtsov Andrey Dunaev Igor Gurov 《Journal of biophotonics》2019,12(6)
The dynamic light scattering methods are widely used in biomedical diagnostics involving evaluation of blood flow. However, there exist some difficulties in quantitative interpretation of backscattered light signals from the viewpoint of diagnostic information. This study considers the application of the high‐speed videocapillaroscopy (VCS) method that provides the direct measurement of the red blood cells (RBCs) velocity into a capillary. The VCS signal presents true oscillation nature of backscattered light caused by moving RBCs. Thus, the VCS signal can be assigned as a reference one with respect to more complicated signals like in laser Doppler flowmetry (LDF). An essential correlation between blood flow velocity oscillations in a separate human capillary and the integral perfusion estimate obtained by the LDF method has been found. The observation of blood flow by the VCS method during upper arm occlusion has shown emergence of the reverse blood flow effect in capillaries that corresponds to the biological zero signal in the LDF. The reverse blood flow effect has to be taken into account in interpretation of LDF signals. 相似文献
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Rka Fekete Viktor Lki Renta Urgyn Kristf Süveges dm Lovas‐Kiss Orsolya Vincze Attila Molnr V. 《Ecology and evolution》2019,9(11):6655-6664
Several important habitats have become threatened in the last few centuries in the Mediterranean Basin due to major changes adopted in land‐use practices. The consequent loss of natural and seminatural orchid habitats leads to the appreciation of small anthropogenic habitats, such as cemeteries and roadside verges. Colonization of cemeteries and roadside verges by orchids has long been known, but no study to date compared the suitability of these two anthropogenic habitats for orchids. Therefore, in this paper our aim was to survey cemeteries and roadside verges and to compare these two habitats regarding their role in conserving Mediterranean terrestrial orchids. We conducted field surveys in three Mediterranean islands, Cyprus, Crete, and Lesbos, where both cemeteries and roadside verges were sampled on a geographically representative scale. We found a total of almost 7,000 orchid individuals, belonging to 77 species in the two anthropogenic habitat types. Roadside verges hosted significantly more individuals than cemeteries in Crete and Lesbos, and significantly more species across all three islands. Our results suggest that although cemeteries have a great potential conservation value in other parts of the world, intensive maintenance practices that characterized cemeteries in these three islands renders them unable to sustain valuable plant communities. On the other hand, roadside verges play a prominent role in the conservation of Mediterranean orchids in Cyprus and Greece. The pioneer status of roadside verges facilitates their fast colonization, while roads serve as ecological corridors in fragmented landscapes. 相似文献
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Gene expression dynamics in deer antler: mesenchymal differentiation toward chondrogenesis 总被引:6,自引:0,他引:6
Gyurján I Molnár A Borsy A Stéger V Hackler L Zomborszky Z Papp P Duda E Deák F Lakatos P Puskás LG Orosz L 《Molecular genetics and genomics : MGG》2007,277(3):221-235
Annual re-growth of deer antler represents a unique example of complete organ regeneration. Because antler mesenchymal cells
retain their embryonic capacity to develop into cartilage or bone, studying antler development provides a natural system to
follow gene expression changes during mesenchymal differentiation toward chondrogenic/osteogenic lineage. To identify novel
genes involved either in early events of mesenchymal cell specialization or in robust bone development, we have introduced
a 3 K heterologous microarray set-up (deer cDNA versus mouse template). Fifteen genes were differentially expressed; genes
for housekeeping, regulatory functions (components of different signaling pathways, including FGF, TGFβ, Wnt), and genes encoding
members of the Polycomb group were represented. Expression dynamics for genes are visualized by an expression logo. The expression
profile of the gene C21orf70 of unknown function is described along with the effects when over-expressed; furthermore the nuclear localization of the
cognate protein is shown. In this report, we demonstrate the particular advantage of the velvet antler model in bone research
for: (1) identification of mesenchymal and precartilaginous genes and (2) targeting genes upregulated in robust cartilage
development.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
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Yan-Hui Wang Hao-Yang Wu Dávid Rédei Qiang Xie Yan Chen Ping-Ping Chen Zhuo-Er Dong Kai Dang Jakob Damgaard Pavel Štys Yan-Zhuo Wu Jiu-Yang Luo Xiao-Ya Sun Viktor Hartung Stefan M. Kuechler Yang Liu Hua-Xi Liu Wen-Jun Bu 《Cladistics : the international journal of the Willi Hennig Society》2019,35(1):42-66
The phylogeny of true bugs (Hemiptera: Heteroptera), one of the most diverse insect groups in terms of morphology and ecology, has been the focus of attention for decades with respect to several deep nodes between the suborders of Hemiptera and the infraorders of Heteroptera. Here, we assembled a phylogenomic data set of 53 taxa and 3102 orthologous genes to investigate the phylogeny of Hemiptera–Heteroptera, and both concatenation and coalescent methods were used. A binode-control approach for data filtering was introduced to reduce the incongruence between different genes, which can improve the performance of phylogenetic reconstruction. Both hypotheses (Coleorrhyncha + Heteroptera) and (Coleorrhyncha + Auchenorrhyncha) received support from various analyses, in which the former is more consistent with the morphological evidence. Based on a divergence time estimation performed on genes with a strong phylogenetic signal, the origin of true bugs was dated to 290–268 Ma in the Permian, the time in Earth's history with the highest concentration of atmospheric oxygen. During this time interval, at least 1007 apomorphic amino acids were retained in the common ancestor of the extant true bugs. These molecular apomorphies are located in 553 orthologous genes, which suggests the common ancestor of the extant true bugs may have experienced large-scale evolution at the genome level. 相似文献