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81.
MultiPLX: automatic grouping and evaluation of PCR primers 总被引:1,自引:0,他引:1
SUMMARY: MultiPLX is a new program for automatic grouping of PCR primers. It can use many different parameters to estimate the compatibility of primers, such as primer-primer interactions, primer-product interactions, difference in melting temperatures, difference in product length and the risk of generating alternative products from the template. A unique feature of the MultiPLX is the ability to perform automatic grouping of large number (thousands) of primer pairs. AVAILABILITY: Binaries for Windows, Linux and Solaris are available from http://bioinfo.ebc.ee/download/. A graphical version with limited capabilities can be used through a web interface at http://bioinfo.ebc.ee/multiplx/. The source code of the program is available on request for academic users. CONTACT: maido.remm@ut.ee. 相似文献
82.
Summary Conventionally fixed and plastic-embedded myocardial tissue from mice treated with 1 mg/kg body weight dexamethasone for 48 h was examined in the electron microscope. The dexamethasone-treated mice showed a marked increase in the accumulation of lipid droplets as compared with control animals. The per cent volume of lipid droplets, calculated by morphometric analysis, showed a significant increase in the dexamethasone-treated mice. No other ultrastructural difference between dexamethasone-treated mice and controls was observed. 相似文献
83.
84.
Partition of lipids between emulsified oil and micellar phases of glyceride-bile salt dispersions 总被引:1,自引:0,他引:1
B Borgstr?m 《Journal of lipid research》1967,8(6):598-608
The composition of the emulsified oil and of the micellar phases obtained when a glyceride-fatty acid mixture is dispersed in bile salt solution has been defined. The micellar phase in equilibrium with the emulsified oil phase was obtained by filtration through Millipore filters. The behavior of different lipids in such systems was defined as the partition ratio, micellar/emulsified oil phase (m/o). Partition of fatty acids was found to be strongly dependent on the chain length of the fatty acid and the pH of the dispersion. The curve for partition against pH for oleic acid was interpreted to show a pK(a) for oleic acid in bile salt solution of approximately 7. The partition between micellar and oil phases is given for a series of lipids of different polarity. No significant difference in behavior was found for cholesterol and sitosterol. A relationship was found between the partition m/o and filtration rates through a Millipore filter in micellar solution. The lower the partition coefficient the lower was the rate of filtration. The results obtained are discussed in relation to the mechanism of absorption of fat from the small intestine. 相似文献
85.
Malene Nygaard Petri Kemppainen James D. M. Speed Reidar Elven Kjell Ivar Flatberg Leif P. Galten Narjes Yousefi Heidi Solstad Mika Bendiksby 《植物分类学报:英文版》2021,59(4):627-641
Carex section Ceratocystis (Cyperaceae) is a group of recently evolved plant species, in which hybridization is frequent, introgression is documented, taxonomy is complex, and morphological boundaries are vague. Within this section, a unified taxonomic treatment of the Carex jemtlandica–Carex lepidocarpa species complex does not exist, and Norway may currently be the sole country accepting species rank for both. Carex jemtlandica is mainly confined to Fennoscandia and is thus a Fennoscandian conservation responsibility. This motivated us to test the principal hypothesis that both C. jemtlandica and C. lepidocarpa represent evolutionary significant units, and that both deserve their current recognition at species level. We investigated their evolutionary distinctiveness in Norway,using restriction site-associated DNA sequencing and ecological niche modeling. Our genomic results reveal two genetic clusters, largely corresponding to C. jemtlandica and C. lepidocarpa that also remain distinct in sympatry, despite clear indications of ongoing hybridization and introgression. The ecological niche modeling suggests that they occupy different environmental niches. Jointly, our results clearly show that C. jemtlandica and C. lepidocarpa represent separately evolving entities that should qualify recognition as evolutionary significant units. Given the high level of introgression compared to other hybridizing species pairs in Carex we recommend treating C. jemtlandica as a subspecies of C. lepidocarpa. 相似文献
86.
Background
Large efforts have recently been made to automate the sample preparation protocols for massively parallel sequencing in order to match the increasing instrument throughput. Still, the size selection through agarose gel electrophoresis separation is a labor-intensive bottleneck of these protocols.Methodology/Principal Findings
In this study a method for automatic library preparation and size selection on a liquid handling robot is presented. The method utilizes selective precipitation of certain sizes of DNA molecules on to paramagnetic beads for cleanup and selection after standard enzymatic reactions.Conclusions/Significance
The method is used to generate libraries for de novo and re-sequencing on the Illumina HiSeq 2000 instrument with a throughput of 12 samples per instrument in approximately 4 hours. The resulting output data show quality scores and pass filter rates comparable to manually prepared samples. The sample size distribution can be adjusted for each application, and are suitable for all high throughput DNA processing protocols seeking to control size intervals. 相似文献87.
Islam MM Wallin R Wynn RM Conway M Fujii H Mobley JA Chuang DT Hutson SM 《The Journal of biological chemistry》2007,282(16):11893-11903
The catabolic pathways of branched-chain amino acids have two common steps. The first step is deamination catalyzed by the vitamin B(6)-dependent branched-chain aminotransferase isozymes (BCATs) to produce branched-chain alpha-keto acids (BCKAs). The second step is oxidative decarboxylation of the BCKAs mediated by the branched-chain alpha-keto acid dehydrogenase enzyme complex (BCKD complex). The BCKD complex is organized around a cubic core consisting of 24 lipoate-bearing dihydrolipoyl transacylase (E2) subunits, associated with the branched-chain alpha-keto acid decarboxylase/dehydrogenase (E1), dihydrolipoamide dehydrogenase (E3), BCKD kinase, and BCKD phosphatase. In this study, we provide evidence that human mitochondrial BCAT (hBCATm) associates with the E1 decarboxylase component of the rat or human BCKD complex with a K(D) of 2.8 microM. NADH dissociates the complex. The E2 and E3 components do not interact with hBCATm. In the presence of hBCATm, k(cat) values for E1-catalyzed decarboxylation of the BCKAs are enhanced 12-fold. Mutations of hBCATm proteins in the catalytically important CXXC center or E1 proteins in the phosphorylation loop residues prevent complex formation, indicating that these regions are important for the interaction between hBCATm and E1. Our results provide evidence for substrate channeling between hBCATm and BCKD complex and formation of a metabolic unit (termed branched-chain amino acid metabolon) that can be influenced by the redox state in mitochondria. 相似文献
88.
Rune Ehrenreich Kuhre Charlotte Bayer Christiansen Seyed Mojtaba Ghiasi Maria Buur Nordskov Gabe Patricia Almine Skat-Rørdam Ida Marie Modvig Thomas Mandrup-Poulsen Reidar Albrechtsen Mette Marie Rosenkilde Bolette Hartmann Nicolai Jacob Wewer Albrechtsen Jens Juul Holst 《Cell metabolism》2019,29(3):719-726.e5
89.
Heidi Iren Saure Vigdis Vandvik Kristian Hassel Ole Reidar Vetaas 《Biological invasions》2014,16(4):775-791
Invasion by non-native conifers may pose a threat to local biodiversity, but knowledge about introduced conifer effects on Northern Hemisphere ecosystems is scarce. The coastal heathlands of north-west Europe are threatened by invasion of native and introduced tree species. We assess how spread of the introduced conifer Sitka spruce (Picea sitchensis (Bong.) Carr.) into European coastal heathlands affect two major functional groups; vascular plants and bryophytes, and how these effects relate to the environmental changes imposed by the developing tree canopies. We compared the impact of introduced Sitka spruce and native Scots pine (Pinus sylvestris L.) by analysing effects on species richness and turnover of vascular plants and bryophytes along fine-scale transects from individual tree stems into open heathland vegetation. Environmental impacts were assessed by measured environmental variables, and the responses of the two species groups were assessed by calculating changes in their respective mean Ellenberg indicator values. Species richness decreased beneath both conifers, related to decreased light and increased nitrogen and pH. Whereas vascular plants responded negatively to poor light conditions beneath dense and low Sitka spruce canopies, bryophytes were more negatively affected by the warmer and drier microclimates beneath Scots pine. Introduced Sitka spruce impacts the sub-canopy environment differently from the native Scots pine, and the two functional plant groups responded differently to these impacts. This suggests that future forests are likely to differ in species richness and composition, depending on whether succession is based on native or introduced coniferous trees. 相似文献
90.
Lundström SL Yang J Källberg HJ Thunberg S Gafvelin G Haeggström JZ Grönneberg R Grunewald J van Hage M Hammock BD Eklund A Wheelock ÅM Wheelock CE 《PloS one》2012,7(3):e33780