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61.
62.
A genomewide association study of skin pigmentation in a South Asian population 总被引:4,自引:0,他引:4 下载免费PDF全文
Stokowski RP Pant PV Dadd T Fereday A Hinds DA Jarman C Filsell W Ginger RS Green MR van der Ouderaa FJ Cox DR 《American journal of human genetics》2007,81(6):1119-1132
We have conducted a multistage genomewide association study, using 1,620,742 single-nucleotide polymorphisms to systematically investigate the genetic factors influencing intrinsic skin pigmentation in a population of South Asian descent. Polymorphisms in three genes—SLC24A5, TYR, and SLC45A2—yielded highly significant replicated associations with skin-reflectance measurements, an indirect measure of melanin content in the skin. The associations detected in these three genes, in an additive manner, collectively account for a large fraction of the natural variation of skin pigmentation in a South Asian population. Our study is the first to interrogate polymorphisms across the genome, to find genetic determinants of the natural variation of skin pigmentation within a human population. 相似文献
63.
Neha Pant Harold Marcotte Harald Brüssow Lennart Svensson Lennart Hammarström 《BMC microbiology》2007,7(1):86
Background
Rotavirus is a worldwide cause of infectious infantile diarrhea that claims over 600,000 lives annually. Recently, two new vaccine candidates have been developed but their efficacy in developing countries, still remains to be proven. Oral delivery of specific immunoglobulins provides passive immunity and is a fast acting treatment for rotavirus diarrhea. Probiotic bacteria have also gained considerable attention lately as treatment for rotavirus diarrhea. Here we report an evaluation of the therapeutic potential of different probiotics and their combination with anti - rotavirus antibodies in a mouse model of rotavirus diarrhea. 相似文献64.
Chromosome engineering,mapping, and transferring of resistance to Fusarium head blight disease from Elymus tsukushiensis into wheat 总被引:1,自引:0,他引:1
65.
Long-term performance of activated carbon air cathodes with different diffusion layer porosities in microbial fuel cells 总被引:2,自引:0,他引:2
Activated carbon (AC) air-cathodes are inexpensive and useful alternatives to Pt-catalyzed electrodes in microbial fuel cells (MFCs), but information is needed on their long-term stability for oxygen reduction. AC cathodes were constructed with diffusion layers (DLs) with two different porosities (30% and 70%) to evaluate the effects of increased oxygen transfer on power. The 70% DL cathode initially produced a maximum power density of 1214±123 mW/m(2) (cathode projected surface area; 35±4 W/m(3) based on liquid volume), but it decreased by 40% after 1 year to 734±18 mW/m(2). The 30% DL cathode initially produced less power than the 70% DL cathode, but it only decreased by 22% after 1 year (from 1014±2 mW/m(2) to 789±68 mW/m(2)). Electrochemical tests were used to examine the reasons for the degraded performance. Diffusion resistance in the cathode was found to be the primary component of the internal resistance, and it increased over time. Replacing the cathode after 1 year completely restored the original power densities. These results suggest that the degradation in cathode performance was due to clogging of the AC micropores. These findings show that AC is a cost-effective material for oxygen reduction that can still produce ~750 mW/m(2) after 1 year. 相似文献
66.
Over two billion people, depending largely on staple foods, suffer from deficiencies in protein and some micronutrients such as iron and zinc. Among various approaches to overcome protein and micronutrient deficiencies, biofortification through a combination of conventional and molecular breeding methods is the most feasible, cheapest, and sustainable approach. An interspecific cross was made between the wheat cultivar 'Chinese Spring' and Aegilops kotschyi Boiss. accession 396, which has a threefold higher grain iron and zinc concentrations and about 33% higher protein concentration than wheat cultivars. Recurrent backcrossing and selection for the micronutrient content was performed at each generation. Thirteen derivatives with high grain iron and zinc concentrations and contents, ash and ash micronutrients, and protein were analyzed for alien introgression. Morphological markers, high molecular weight glutenin subunit profiles, anchored wheat microsatellite markers, and GISH showed that addition and substitution of homoeologous groups 1, 2, and 7 chromosomes of Ae. kotschyi possess gene(s) for high grain micronutrients. The addition of 1U/1S had high molecular weight glutenin subunits with higher molecular weight than those of wheat, and the addition of 2S in most of the derivatives also enhanced grain protein content by over 20%. Low grain protein content in a derivative with a 2S-wheat translocation, waxy leaves, and absence of the gdm148 marker strongly suggests that the gene for higher grain protein content on chromosome 2S is orthologous to the grain protein QTL on the short arm of group 2 chromosomes. 相似文献
67.
Topoisomerase I (topo I) is an essential enzyme for vital cellular processes. Inhibition of topo I activities is lethal and leads to cell death, thus establishing topo I as a promising target for cancer treatment. Camptothecin, a natural alkaloid, inhibits topo I. Topotecan and irinotecan, synthetic derivatives of camptothecin, are the most potent anticancer drugs in clinical use. However, several limitations of camptothecins such as solubility, toxicity, stability, resistance and the required high drug dose have encouraged the development of non-camptothecin topo I inhibitors. Natural alkaloid benzo[c]phenanthridines and synthetic indenoisoquinolines have been extensively studied as alternatives to camptothecin. Interestingly, these non-camptothecin topo I inhibitors share a common 3-arylisoquinoline scaffold. This review will describe the development of novel indeno[1,2-c]isoquinolines, isoindolo[2,1-b]isoquinolines, 12-oxobenzo[c]phenanthridines and benz[b]oxepines with a 3-arylisoquinoline nucleus as topo I inhibitors. 相似文献
68.
Mercury uptake and translocation in Impatiens walleriana plants grown in the contaminated soil from Oak Ridge 总被引:1,自引:0,他引:1
Mercury (Hg) contaminated soils from Oak Ridge, Tennessee were investigated for phytoavailability of mercury as measured by degree of Hg translocation in aboveground biomass of Impatiens walleriana plants grown in the soils. After 90 days of incubation, results revealed a higher concentration of total Hg in the leaves than in the flowers or the stems. Plants that were grown in the soils with higher Hg concentrations showed significantly higher Hg uptake and translocation in the aboveground plant-biomass, and the correlation with the initial soil-Hg was significant for the leaves and the stems in the plants that were tested. On an average, only 4.06 microg of Hg could be found in the above ground plant biomass of all the plants, compared to an average 3673.50 microg of initial total Hg concentrations in these soils. Statistical analysis revealed a greater affinity of Hg for the soil carbon, which supported the finding of this study on low soil Hg bioavailability. 相似文献
69.
Protein—protein interactions play an important role in regulating the expression of huntingtin protein (htt). Expansion of
polyglutamine tracts in htt results in neurodegenerative Huntington disease. Huntingtin interacting protein (HIP14) is an
important interacting partner of htt and the altered interactions have been proposed to play an important role in disease
progression. In the present study, an attempt has been made to explore the potential of several known Huntington inhibitors
to inhibit HIP14. The docking studies have resulted in the identification of a novel binding site for these inhibitors distinct
from the previously known ankyrin repeat domain. The results have been validated using geometry based docking transformations
against the other binding pocket. The specificity of binding has been determined with high values of both accuracy and precision.
Nine potential inhibitors obtained after screening belong to three distinct classes of compounds viz, carbohydrates (deoxy-glucose), alcohols (including phenolic scaffold) and tetracycline. The compounds form stable complex
with protein exhibiting optimal intermolecular and Gibbs free energy. The hydrogen bonding and hydrophobic interactions predominantly
contribute to the stability of these complexes. The present study identifies metoprolol, minocyclines and 18 F fluorodeoxyglucose
as the best inhibitors that bind specifically to the new site. Therefore, these compounds can further be exploited for their
potential to serve in the diagnosis and treatment of Huntington disease. The quantitative predictions provide a scope for
experimental testing in future. 相似文献
70.