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141.
Allosathes anitae n. sp. Casanueva & González-Acu?a (Astigmata: Crypturoptidae), collected on the Chilean tinamou Nothoprocta perdicaria (Tinamiformes: Tinamidae) from different localities of the ?uble Province, Chile, is described. Comments on its affinities and differences with Allosathes anepiandrius Gaud, Atyeo & Berla are also included. 相似文献
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Application of polylocus biallelic systems of PCR along with monolocus SSR-analysis is very promising approach for detailed characterization, differentiation and identification of crop varieties. Microsatellite sequences and LTR retratransposon fragments are known to be the most variable in plant genome. They can be used in PCR analysis as IRAP and REMAP. Conditions of IRAP and REMAP analyses of intra- and intervariety polymorphism of the barley varieties of Odessa breeding have been elaborated. The detailed genotype formulas are represented which reflect the intravariety polimorphism and make it possible to detect the changes in variety structure in the course of seed production process. 相似文献
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目的:探讨钒配合物LMc对拓扑异构酶Ⅰ、Ⅱ(Topo-Ⅰ、Topo-Ⅱ)的影响及其抗肿瘤活性。方法:采用DNA松弛实验观察LMC对Topo-Ⅰ、活性的影响并探讨其相关分子作用机制;采用MTT法、流式细胞术在细胞水平观察了IMC的抗肿瘤作用。结果:LMC可明显抑制Topo-Ⅰ活性,对Topo-Ⅱ无明显抑制作用,对多种肿瘤细胞株A549、Hela、BEL-7402具有明显抑制生长的作用,且可将细胞阻断在G2/M期,而对正常细胞株L-02生长无明显影响。结论:钒配合物LMC具有抑制Topo-Ⅰ活性而发挥抗肿瘤的作用。 相似文献
146.
GUILLAUME EVANNO†‡ EMMANUEL CASTELLA§ CÉLINE ANTOINE§ GABRIELLE PAILLAT§ JÉRÔME GOUDET 《Molecular ecology》2009,18(6):1137-1144
We examined the spatial and temporal variation of species diversity and genetic diversity in a metacommunity comprising 16 species of freshwater gastropods. We monitored species abundance at five localities of the Ain river floodplain in southeastern France, over a period of four years. Using 190 AFLP loci, we monitored the genetic diversity of Radix balthica , one of the most abundant gastropod species of the metacommunity, twice during that period. An exceptionally intense drought occurred during the last two years and differentially affected the study sites. This allowed us to test the effect of natural disturbances on changes in both genetic and species diversity. Overall, local (alpha) diversity declined as reflected by lower values of gene diversity H S and evenness. In parallel, the among-sites (beta) diversity increased at both the genetic ( F ST ) and species ( F STC ) levels. These results suggest that disturbances can lead to similar changes in genetic and community structure through the combined effects of selective and neutral processes. 相似文献
147.
The method of affinity coelectrophoresis was used to study the binding of
nine representative glycosaminoglycan (GAG)-binding proteins, all thought
to play roles in nervous system development, to GAGs and proteoglycans
isolated from developing rat brain. Binding to heparin and non-neural
heparan and chondroitin sulfates was also measured. All nine
proteins-laminin-1, fibronectin, thrombospondin-1, NCAM, L1, protease
nexin-1, urokinase plasminogen activator, thrombin, and fibroblast growth
factor-2-bound brain heparan sulfate less strongly than heparin, but the
degree of difference in affinity varied considerably. Protease nexin-1
bound brain heparan sulfate only 1.8- fold less tightly than heparin
(Kdvalues of 35 vs. 20 nM, respectively), whereas NCAM and L1 bound heparin
well (Kd approximately 140 nM) but failed to bind detectably to brain
heparan sulfate (Kd>3 microM). Four proteins bound brain chondroitin
sulfate, with affinities equal to or a few fold stronger than the same
proteins displayed toward cartilage chondroitin sulfate. Overall, the
highest affinities were observed with intact heparan sulfate proteoglycans:
laminin-1's affinities for the proteoglycans cerebroglycan (glypican-2),
glypican-1 and syndecan-3 were 300- to 1800-fold stronger than its affinity
for brain heparan sulfate. In contrast, the affinities of fibroblast growth
factor-2 for cerebroglycan and for brain heparan sulfate were similar.
Interestingly, partial proteolysis of cerebroglycan resulted in a >400-
fold loss of laminin affinity. These data support the views that (1)
GAG-binding proteins can be differentially sensitive to variations in GAG
structure, and (2) core proteins can have dramatic, ligand-specific
influences on protein-proteoglycan interactions.
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