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排序方式: 共有633条查询结果,搜索用时 15 毫秒
71.
72.
Pikula J Bandouchova H Novotny L Meteyer CU Zukal J Irwin NR Zima J Martínková N 《Journal of wildlife diseases》2012,48(1):207-211
White-nose syndrome, associated with the fungal skin infection geomycosis, caused regional population collapse in bats in North America. Our results, based on histopathology, show the presence of white-nose syndrome in Europe. Dermatohistopathology on two bats (Myotis myotis) found dead in March 2010 with geomycosis in the Czech Republic had characteristics resembling Geomyces destructans infection in bats confirmed with white-nose syndrome in US hibernacula. In addition, a live M. myotis, biopsied for histopathology during hibernation in April 2011, had typical fungal infection with cupping erosion and invasion of muzzle skin diagnostic for white-nose syndrome and conidiospores identical to G. destructans that were genetically confirmed as G. destructans. 相似文献
73.
During an initial study in searching for the alternative derivatives suitable for photolabeling of neuroactive steroids, perfluorobenzoates and perfluorobenzamides in position 17 of 5β-androstan-3α-ol were synthesized from the corresponding 17-hydroxy and 17-amino derivatives. After transformation into glutamates or sulfates, 17α-epimers had comparable inhibitory activity at NMDA receptors to the natural neurosteroid (20-oxo-5β-pregnan-3β-yl sulfate), however, were more potent (2- to 36-fold) than their 17β-substituted analogs. In one case, fluorine in position 4' of perfluorobenzoate group was substituted with azide and activity of the final glutamate was retained comparing with the corresponding perfluorobenzoate. The series was expanded with perfluorobenzoyl derivatives of pregnanolone: Perfluorobenzamide of glutamate and perfluorobenzoate of 11α-hydroxy pregnanolone were prepared and tested. From nine tested compounds, four of them exhibit very good inhibition activity and can serve as promising leads for photolabeling experiments. 相似文献
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76.
Ladislav Bocak 《ZooKeys》2012,(241):55-66
The Javanese fauna of the species group Cautires obsoletus is revised. Altogether, eight Javanese species were classified in the group; five of them are proposed to be junior subjective synonyms: Cautires fruhstorferi Dudkova & Bocak, 2010, a replacement name of Bulenides lineatus Pic, 1921, Cautires javanicus Bourgeois, 1883, Cautires inhumeralis (Pic, 1921), Cautires nigromaculatus (Pic, 1925), and Cautires pudicus (Kleine, 1931) (all synonymized to Cautires obsoletus Waterhouse, 1879). Three Javanese species are redescribed: Cautires apicalis (Pic, 1925), Cautires obsoletus (Waterhouse, 1878), and Cautires singularithorax (Pic, 1925). Cautires apicalis (Pic, 1925) is removed from the synonymy of Cautires corporaali (Pic, 1921) and reinstated as a valid name. Three new species are proposed: Cautires walteri
sp. n., Cautires taoi
sp. n., and Cautires sukosarensis
sp. n. All species are keyed and principal diagnostic characters are illustrated. The distribution and relationships to Cautires fauna of other Great Sundas islands are briefly discussed. 相似文献
77.
78.
Interleukin-1α (IL-1α) is a proinflammatory cytokine and a key player in host immune responses in higher eukaryotes. IL-1α has pleiotropic effects on a wide range of cell types, and it has been extensively studied for its ability to contribute to various autoimmune and inflammation-linked disorders, including rheumatoid arthritis, Alzheimer's disease, systemic sclerosis and cardiovascular disorders. Interestingly, a significant proportion of IL-1α is translocated to the cell nucleus, in which it interacts with histone acetyltransferase complexes. Despite the importance of IL-1α, little is known regarding its binding targets and functions in the nucleus. We took advantage of the histone acetyltransferase (HAT) complexes being evolutionarily conserved from yeast to humans and the yeast SAGA complex serving as an epitome of the eukaryotic HAT complexes. Using gene knock-out technique and co-immunoprecipitation of the IL-1α precursor with TAP-tagged subunits of the yeast HAT complexes, we mapped the IL-1α-binding site to the HAT/Core module of the SAGA complex. We also predicted the 3-D structure of the IL-1α N-terminal domain, and by employing structure similarity searches, we found a similar structure in the C-terminal regulatory region of the catalytic subunit of the AMP-activated/Snf1 protein kinases, which interact with HAT complexes both in mammals and yeast, respectively. This finding is further supported with the ability of the IL-1α precursor to partially rescue growth defects of snf1Δ yeast strains on media containing 3-Amino-1,2,4-triazole (3-AT), a competitive inhibitor of His3. Finally, the careful evaluation of our data together with other published data in the field allows us to hypothesize a new function for the ADA complex in SAGA complex assembly. 相似文献
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80.
Martin Straka Ladislav Paule Ovidiu Ionescu Jozef ?tofík Michal Adamec 《Conservation Genetics》2012,13(1):153-164
The formerly large, continuous brown bear population of the Carpathians has experienced a radical decrease in population size
due to human activities which have resulted in splitting the population into the larger Eastern Carpathian and the smaller
Western Carpathian subpopulations. In the Western Carpathians, brown bears came close to extinction at the beginning of 1930s,
but thanks to both conservation and management efforts the bear population has begun to recover. In contrast, the Eastern
Carpathian subpopulation in Romania has never dropped below 800 individuals, potentially preserving the original amount of
genetic variation. In this paper we present results of a genetic study of brown bear subpopulations distributed in the Slovak
and Romanian sections of the Carpathians using 13 nuclear microsatellites. The documented level of genetic differentiation
between the Western and Eastern Carpathian subpopulations reflects the isolation which lasted almost 100 years. Furthermore,
the existence of two, different, genetic clusters within the Western Carpathians despite close geographic proximity indicates
that human-caused fragmentation and isolation have resulted in significant genetic divergence. Although the subpopulations
display an indication of genetic bottleneck, the level of genetic diversity is within the range commonly observed in different
brown bear populations. The results presented here point out the significance of human exploitation to the population structure
of this large carnivore species. Future management efforts should be aimed at securing and restoring the connectivity of forested
habitats, in order to preserve the genetic variation of the Carpathian brown bear subpopulations and to support the gene flow
between them. 相似文献