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61.
Pathways regulating apoptosis during patterning and development 总被引:5,自引:0,他引:5
The patterning and development of multicellular organisms require a precisely controlled balance between cell proliferation, differentiation and death. The regulation of apoptosis is an important aspect to achieve this balance, by eliminating unnecessary or mis-specified cells which, otherwise, may have harmful effects on the whole organism. Apoptosis is also important for the morphogenetic processes that occur during development and that lead to the sculpting of organs and other body structures. Here, we review recent progress in understanding how apoptosis is regulated during development, focusing on studies using Drosophila or Caenorhabditis elegans as model organisms. 相似文献
62.
Susana Martins Bruno Sarmento Eliana B. Souto Domingos C. Ferreira 《Carbohydrate polymers》2007,69(4):725-731
Oral administration of insulin requires protein protection from degradation in the gastric environment and its absorption improvement in the intestinal tract. To achieve this objective several types of microspheres composed of alginate, chitosan and dextran sulphate have been prepared by ionotropic gelation. Parameters such as the mean particle size, swelling behaviour, insulin encapsulation efficiency, loading capacity and release profiles in simulated gastric and intestinal fluids have been compared for the systems developed. In this study, attempts have been made to increase insulin protection and to improve its release from microspheres by reinforcing the alginate matrix with chitosan and/or dextran sulphate. Dextran sulphate was able to avoid insulin release at pH 1.2, protecting the protein from the acidic environment and reducing the total insulin released at pH 6.8. This effect was explained by an interaction between the permanent negatively charged groups of dextran sulphate and insulin molecules. 相似文献
63.
Tiago Pereira Galya Ivanova Ana Rita Caseiro Paula Barbosa Paulo Jorge Bártolo José Domingos Santos Ana Lúcia Luís Ana Colette Maurício 《PloS one》2014,9(11)
Human mesenchymal stem cells (hMSCs) from umbilical cord (UC) blood (UCB) and matrix are tested clinically for a variety of pathologies but in vitro expansion using culture media containing fetal bovine serum (FBS) is essential to achieve appropriate cell numbers for clinical use. Human UCB plasma (hUCBP) can be used as a supplement for hMSCs culture, since UCB is rich in soluble growth factors and due to worldwide increased number of cryopreserved UCB units in public and private banks, without the disadvantages listed for FBS. On the other hand, the culture media enriched in growth factors produced by these hMSCs in expansion (Conditioned medium - CM) can be an alternative to hMSCs application. The CM of the hMSCs from the UC might be a better therapeutic option compared to cell transplantation, as it can benefit from the local tissue response to the secreted molecules without the difficulties and complications associated to the engraftment of the allo- or xeno-transplanted cells. These facts drove us to know the detailed composition of the hUCBP and CM, by 1H-NMR and Multiplexing LASER Bead Technology. hUCBP is an adequate alternative for the FBS and the CM and hUCBP are important sources of growth factors, which can be used in MSCs-based therapies. Some of the major proliferative, chemotactic and immunomodulatory soluble factors (TGF-β, G-CSF, GM-CSF, MCP-1, IL-6, IL-8) were detected in high concentrations in CM and even higher in hUCBP. The results from 1H-NMR spectroscopic analysis of CM endorsed a better understanding of hMSCs metabolism during in vitro culture, and the relative composition of several metabolites present in CM and hUCBP was obtained. The data reinforces the potential use of hUCBP and CM in tissue regeneration and focus the possible use of hUCBP as a substitute for the FBS used in hMSCs in vitro culture. 相似文献
64.
65.
Domingos Cardoso Luciano P. de Queiroz R. Toby Pennington Haroldo C. de Lima Émile Fonty Martin F. Wojciechowski Matt Lavin 《American journal of botany》2012,99(12):1991-2013
• Premise of study: Phylogenetic relationships of the papilionoid legumes (Papilionoideae) reveal that the early branches are more highly diverse in floral morphology than are other clades of Papilionoideae. This study attempts for the first time to comprehensively sample the early-branching clades of this economically and ecologically important legume subfamily and thus to resolve relationships among them. • Methods: Parsimony and Bayesian phylogenetic analyses of the plastid matK and trnL intron sequences included 29 genera not yet sampled in matK phylogenies of the Papilionoideae, 11 of which were sampled for DNA sequence data for the first time. • Key results: The comprehensively sampled matK phylogeny better resolved the deep-branching relationships and increased support for many clades within Papilionoideae. The potentially earliest-branching papilionoid clade does not include any genus traditionally assigned to tribe Swartzieae. Dipterygeae is monophyletic with the inclusion of Monopteryx. The genera Aldina and Amphimas represent two of the nine main but as yet unresolved lineages comprising the large 50-kb inversion clade within papilionoids. The quinolizidine-alkaloid-accumulating genistoid clade is expanded to include a strongly supported subclade containing Ormosia and the previously unplaced Clathrotropis s.s., Panurea, and Spirotropis. Camoensia is the first-branching genus of the core genistoids. • Conclusions: The well-resolved phylogeny of the earliest-branching papilionoids generated in this study will greatly facilitate the efforts to redefine and stabilize the classification of this legume subfamily. Many key floral traits did not often predict phylogenetic relationships, so comparative studies on floral evolution and plant–animal interactions, for example, should also benefit from this study. 相似文献
66.
José Lino Costa Isabel Domingos Carlos A. Assis Pedro R. Almeida Francisco Moreira Eric Feunteun Maria José Costa 《Environmental Biology of Fishes》2008,81(4):421-434
A total of 1,816 eels were sampled in 1988, from seven sampling areas. Four areas were located in brackish water and the remaining
three were located in freshwater reaches of the Tagus river basin. Eels were more abundant in the middle estuary and decreased
both in the upstream and in the downstream directions, with a predominance of males in higher density areas. Smaller individuals
preferred more peripheral areas, such as margins and upper reaches in the brackish water zone, and the tributaries of the
freshwater habitats. It was assumed that this distribution pattern resulted from three main factors: (i) the dominance of
larger specimens; (ii) the need to avoid predators and; (iii) the search for better trophic conditions. The condition of the
individuals generally decreased toward the upper reaches, apparently due to a corresponding decrease in feeding intensity.
The presence of the Belver dam in the main river, 158 km upstream from the sea, seemed to impose major alterations to the
described patterns. The concentration of specimens below this impassable obstacle yielded a reduction in the proportion of
females and a decrease in the condition and survival of the eels, contributing to a reduction in the spawning success of this
population. Suggestions to diminish the effects of the dam, and to preserve the fishery are also presented. 相似文献
67.
Rodrigo R. Domingues Domingos Garrone-Neto Alexandre W. S. Hilsdorf Otto B. F. Gadig 《Journal of fish biology》2019,94(3):512-516
In this study we tested the use of mucus from five species of Neotropical marine batoid elasmobranchs to extract genomic DNA for barcoding and phylogenetic analysis. The DNA from all individuals sampled was successfully amplified and sequenced for molecular barcode, allowing 99–100% accuracy to the species level. This method proved to provide reliable and good-quality DNA for barcoding and phylogenetic analysis of Neotropical elasmobranchs, through rapid handling and with low disturbance to animals. 相似文献
68.
Detoni CB de Oliveira DM Santo IE Pedro AS El-Bacha R da Silva Velozo E Ferreira D Sarmento B de Magalhães Cabral-Albuquerque EC 《Journal of liposome research》2012,22(1):1-7
Zanthoxylum tinguassuiba essential oil (ZtEO) contains α-bisabolol, a known antiglioma sesquiterpene, among other potentially active substances. Medical applications of this essential oil require advances in the design of distinctive carriers due to its low water solubility and easy degradation by heat, light, and oxygen. The aim of this work was to evaluate enhancement in oxidative stability and the ability to reduce glioblastoma cell viability of ZtEO loaded into liposomes. Multi- and unilamellar vesicles were prepared to carry ZtEO. By using thermal analysis, it was observed that thermal-oxidative stability of the liposomal ZtEO was enhanced, when compared to its free form. Liposomal ZtEO also presented significant apoptotic-inducing activity for glioma cells. These results show that liposomal systems carrying ZtEO may be a potential alternative for gliobastoma treatment. 相似文献
69.
Cavasini CE De Mattos LC Alves RT Couto AA Calvosa VS Domingos CR Castilho L Rossit AR Machado RL 《Human biology; an international record of research》2006,78(2):215-219
We compared the serological phenotypic frequencies of ABO, MNSs, and Duffy in 417 blood donors and 309 malaria patients from four Brazilian Amazon areas. Our results suggest no correlation between ABO phenotype and malaria infection in all areas studied. We observed significant correlation between the S +s +, S +s -, and S -s + phenotypes and malaria infection in three areas. Some of the Duffy phenotypes showed significant correlation between donors and malaria patients in different areas. These data are an additional contribution to the establishment of differential host susceptibility to malaria. 相似文献
70.
Renan Janke Bosque Jente Ottenburghs Cecília Rodrigues Vieira Fabrícius Maia Chaves Bicalho Domingos 《Evolution; international journal of organic evolution》2020,74(11):2541-2543
Mimicry can directly affect the evolutionary history of models, mimics, and signal receivers. Mimics often use multimodal signaling to deceive receivers. Jamie et al. showed that brood parasitic birds display multimodal signaling of mimetic traits triggered by sexual and filial imprinting on host species. These resulting adaptations can interact with premating isolation barriers to strengthen reproductive isolation and potentially drive sympatric speciation. 相似文献