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Anabel Fernndez‐Iglesias Martí Ortega‐Ribera Sergi Guix‐Muntet Jordi Gracia‐Sancho 《Journal of cellular and molecular medicine》2019,23(2):877-886
Liver cells isolated from pre‐clinical models are essential tools for studying liver (patho)physiology, and also for screening new therapeutic options. We aimed at developing a new antibody‐free isolation method able to obtain the four main hepatic cell types (hepatocytes, liver sinusoidal endothelial cells [LSEC], hepatic macrophages [HMΦ] and hepatic stellate cells [HSC]) from a single rat liver. Control and cirrhotic (CCl4 and TAA) rat livers (n = 6) were perfused, digested with collagenase and mechanically disaggregated obtaining a multicellular suspension. Hepatocytes were purified by low revolution centrifugations while non‐parenchymal cells were subjected to differential centrifugation. Two different fractions were obtained: HSC and mixed LSEC + HMΦ. Further LSEC and HMΦ enrichment was achieved by selective adherence time to collagen‐coated substrates. Isolated cells showed high viability (80%‐95%) and purity (>95%) and were characterized as functional: hepatocytes synthetized albumin and urea, LSEC maintained endocytic capacity and in vivo fenestrae distribution, HMΦ increased expression of inflammatory markers in response to LPS and HSC were activated upon in vitro culture. The 4 in 1 protocol allows the simultaneous isolation of highly pure and functional hepatic cell sub‐populations from control or cirrhotic single livers without antibody selection. 相似文献
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Casas AM Djemel A Ciudad FJ Yahiaoui S Ponce LJ Contreras-Moreira B Gracia MP Lasa JM Igartua E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(7):1293-1304
In barley, three genes are responsible for the vernalization requirement: VrnH1, VrnH2 and VrnH3. The winter growth habit of barley requires the presence of a recessive VrnH1 allele, together with an active VrnH2 allele. The candidate for VrnH3 (HvFT1) has been recently identified, with evidences pointing at a central role in the integration of the vernalization and photoperiod pathways. Functional polymorphisms have been proposed, but experimental evidence of their role on agronomic performance and adaptation is needed. We examined allelic variation at the promoter and intron 1 of the HvFT1 gene in a landrace collection of barley, finding a high diversity level, with its geographic distribution correlated with latitude. Focusing on genotypes with winter alleles in VrnH1 and VrnH2, an association analysis of the four main HvFT1 haplotypes found in the landrace collection detected differences in time to flowering. Landraces with the intron 1 TC allele, prevalent in the south, flowered 6?C7?days earlier than those with the AG allele, under natural conditions. These results were validated in an independent F2 population. In both data sets, the effect found was similar, but in opposite direction to that described in literature. The polymorphism reported at intron 1 contributes to variation in flowering time under field conditions. We have found that polymorphisms at the promoter also contribute to the effect of the gene on flowering time under field and controlled conditions. The variety of HvFT1 alleles described constitutes an allelic series that may have been a factor in agro-ecological adaptation of barley. 相似文献
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Gracia P. González-Porter Frank Hailer Oscar Flores-Villela Rony García-Anleu Jesús E. Maldonado 《Conservation Genetics》2011,12(5):1229-1242
We conducted a phylogeographic analysis of the strictly aquatic and critically endangered Central American river turtle, Dermatemys mawii, as part of a conservation management program for the species. We sampled 238 individuals from 15 different localities throughout
the species range. Using sequence fragments from the mtDNA Cyt b and ND4 genes, we identified 16 different haplotypes. Overall, our results reveal a signal of phylogeographic structure throughout
the range, which appears to have been secondarily blurred by extensive gene flow. Notably, this also applies to genetic structuring
across three major hydrological basins that pose biogeographic breaks in other aquatic taxa. Divergence times of mtDNA haplotypes
in D. mawii suggest that the main lineages split in the Pliocene–Pleistocene (3.73–0.227 MA) and demographic tests indicate that the
species has undergone drastic demographic size fluctuations since this time period. One ancient haplotype (1D) was found to
exhibit sequence divergence of up to 2% from other haplogroups. Divergence of this magnitude is indicative of species level
differentiation in other turtle genera. Haplotype 1D was found in only two localities, Sarstun and Salinas, but specimens
with other haplotypes were also found in those localities. It is not known whether the individuals with the 1D haplotype interbreed
with non-1D individuals. Our results suggest that human activity, such as harvesting and long distance transport of animals,
may have influenced the current patterns of genetic diversity. For more than 2000 years, D. mawii has been consumed by people from Middle American cultures, and the archeological record contains strong evidence that the
Mayans transported animals between villages and far away from their natural distribution range. Therefore, the large-scale
pattern of haplotype sharing even across hydrological barriers, the observed low haplotype diversity in some populations and
the contemporary absence of a pronounced phylogeographic pattern is likely due to a combination of population expansions,
gene flow, extensive human-mediated-movements and recent bottlenecks resulting from over-harvesting. 相似文献
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Gracia Patricia Blanch Gema Flores Maria del Mar Caja Maria Luisa Ruiz del Castillo 《Phytochemical analysis : PCA》2009,20(5):427-433
Introduction – Methyl jasmonate (MJ) contains two chiral centres at C‐3 and C‐7 in its chemical structure, which implies that it can exist in four possible stereoisomeric forms, namely (+)‐MJ, (?)‐MJ, (+)‐epiMJ and (?)‐epiMJ. The absolute configuration of the two side chains of MJ affects the biological activity associated with this compound. Objective – To isolate pure (?)‐MJ from a natural source, Jasminum polyanthum Franch., with the intention of increasing the knowledge about its biological properties, including its effect on the biosynthesis of plant metabolites. Methodology – The method used was based on steam distillation extraction (SDE) as an extraction technique followed by high‐performance liquid chromatography (HPLC) as a purification procedure. The HPLC flow‐rate as well as the number of fractions accumulated were optimised to achieve the concentration and purity required. Results – The employment of 0.3 mL/min as HPLC flow‐rate and the accumulation of three HPLC fractions allowed the required enantiomeric purity (95%) and concentration (0.36 mg/L in each HPLC fraction) to efficiently obtain (?)‐methyl jasmonate from Jasminum polyanthum Franch. to be achieved. Conclusion – The approach proposed may enable the properties and effect of pure (?)‐MJ on plant responses to be studied. The use of a natural source to obtain (?)‐MJ is presented as an alternative to the enantioselective synthesis and enantiomeric resolution from the standard racaemic mixture. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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María Cruz Ortega Ana Gracia Ignacio Martínez Rolf Quam Juan Luis Arsuaga 《L'Anthropologie》2009,113(1):233
A fossil human femur of Homo heidelbergensis from the site of the Sima de los Huesos (Atapuerca, Spain) was reconstructed from two main proximal and distal portions and numerous smaller fragments from the diaphysis. The use of an evaporative process to separate the bone fragments during their restoration represents an innovative approach in restoring paleontological materials and the intervention has resulted in the reconstruction of a complete femur. To avoid excessive manipulation of the reconstructed femur, a mold (negative) and cast (positive) were made of the restored specimen. This case study provides general protocols which can be widely applied to the restoration of paleontological materials from the moment of their excavation until they are deposited in a research center. 相似文献
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Bárbara Herrera Francisco Gracia Paulo Araya Alejandro Toro-Labbé 《Journal of molecular modeling》2009,15(4):405-410
A theoretical study on (ZrO2)
n
(n = 1–5) and Cu/ZrO2 oligomers is presented, DFT/B3LYP/6-31G** calculations along with Lanl2DZ pseudopotentials on metallic centers have been
used to predict ionization potentials and electron affinities, chemical potentials and bandgaps indicating that the reactivity
reaches reasonably constant values at n = 5. The effect of copper atoms adsorbed on (ZrO2)
n
is discussed and the reactivity of oligomers of ZrO2 and Cu/ZrO2 are compared, results indicate that Cu activates the systems by localizing the specific nucleophilic and electrophilic reactivity. 相似文献
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Iodine deficiency is a factor that may compromise child development, but is not the only one. Other health determinants, some of them outside the healthcare system, are able to influence development. Fighting iodine deficiency may be a pragmatic and useful strategy if it is found to be not maleficent, beneficial to health, and cost-effective, and does not make us lose the notion that child development goes beyond psychomotor or cognitive performance. This article analyzes such constraints from a critical point of view. 相似文献