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81.
Marieke De Craemer Mina Lateva Violeta Iotova Ellen De Decker Ma?té Verloigne Ilse De Bourdeaudhuij Odysseas Androutsos Piotr Socha Zbigniew Kulaga Luis Moreno Berthold Koletzko Yannis Manios Greet Cardon the ToyBox-study group 《PloS one》2015,10(3)
Background
The aim of the current study was to compare levels of energy balance-related behaviours (physical activity, sedentary behaviour, and dietary behaviours (more specifically water consumption, sugar-sweetened beverage consumption and unhealthy snacking)) in four- to six-year-old preschoolers from six European countries (Belgium, Bulgaria, Germany, Greece, Poland, and Spain) within the ToyBox cross-sectional study.Methods
A sample of 4,045 preschoolers (4.77 ± 0.43 years; 52.2% boys) had valid physical activity data (steps per day), parents of 8,117 preschoolers (4.78 ± 0.46 years; 53.0% boys) completed a parental questionnaire with questions on sedentary behaviours (television viewing, computer use, and quiet play), and parents of 7,244 preschoolers (4.77 ± 0.44 years; 52.0% boys) completed a food frequency questionnaire with questions on water consumption, sugar-sweetened beverage consumption and unhealthy snacking.Results
The highest levels of physical activity were found in Spain (12,669 steps/day on weekdays), while the lowest levels were found in Bulgaria and Greece (9,777 and 9,656 steps/day on weekdays, respectively). German preschoolers spent the least amount of time in television viewing (43.3 min/day on weekdays), while Greek preschoolers spent the most time in television viewing (88.5 min/day on weekdays). A considerable amount of time was spent in quiet play in all countries, with the highest levels in Poland (104.9 min/day on weekdays), and the lowest levels in Spain (60.4 min/day on weekdays). Belgian, German, and Polish preschoolers had the lowest intakes of water and the highest intakes of sugar-sweetened beverages. The intake of snacks was the highest in Belgian preschoolers (73.1 g/day) and the lowest in Greek preschoolers (53.3 g/day).Conclusions
Across six European countries, differences in preschoolers’ energy balance-related behaviours were found. Future interventions should target European preschoolers’ energy balance-related behaviours simultaneously, but should apply country-specific adaptations. 相似文献82.
83.
André R. A. Marques Jan Aten Roelof Ottenhoff Cindy P. A. A. van Roomen Daniela Herrera Moro Nike Claessen María Fernanda Vinueza Veloz Kuikui Zhou Zhanmin Lin Mina Mirzaian Rolf G. Boot Chris I. De Zeeuw Herman S. Overkleeft Yildiz Yildiz Johannes M. F. G. Aerts 《PloS one》2015,10(8)
The enzyme glucocerebrosidase (GBA) hydrolyses glucosylceramide (GlcCer) in lysosomes. Markedly reduced GBA activity is associated with severe manifestations of Gaucher disease including neurological involvement. Mutations in the GBA gene have recently also been identified as major genetic risk factor for Parkinsonism. Disturbed metabolism of GlcCer may therefore play a role in neuropathology. Besides lysosomal GBA, cells also contain a non-lysosomal glucosylceramidase (GBA2). Given that the two β-glucosidases share substrates, we speculated that over-activity of GBA2 during severe GBA impairment might influence neuropathology. This hypothesis was studied in Niemann-Pick type C (Npc1
-/-) mice showing secondary deficiency in GBA in various tissues. Here we report that GBA2 activity is indeed increased in the brain of Npc1
-/- mice. We found that GBA2 is particularly abundant in Purkinje cells (PCs), one of the most affected neuronal populations in NPC disease. Inhibiting GBA2 in Npc1
-/- mice with a brain-permeable low nanomolar inhibitor significantly improved motor coordination and extended lifespan in the absence of correction in cholesterol and ganglioside abnormalities. This trend was recapitulated, although not to full extent, by introducing a genetic loss of GBA2 in Npc1
-/- mice. Our findings point to GBA2 activity as therapeutic target in NPC. 相似文献
84.
Katja Pfafferott Pooja Deshpande Elizabeth McKinnon Shahzma Merani Andrew Lucas David Heckerman Simon Mallal Mina John Silvana Gaudieri Michaela Lucas 《PloS one》2015,10(6)
Characterisation of Hepatitis C virus (HCV)-specific CD8+ T-cell responses in the context of multiple HCV exposures is critical to identify broadly protective immune responses necessary for an effective HCV vaccine against the different HCV genotypes. However, host and viral genetic diversity complicates vaccine development. To compensate for the observed variation in circulating autologous viruses and host molecules that restrict antigen presentation (human leucocyte antigens; HLA), this study used a reverse genomics approach that identified sites of viral adaptation to HLA-restricted T-cell immune pressure to predict genotype-specific HCV CD8+ T-cell targets. Peptides representing these putative HCV CD8+ T-cell targets, and their adapted form, were used in individualised IFN-γ ELISpot assays to screen for HCV-specific T-cell responses in 133 HCV-seropositive subjects with high-risk of multiple HCV exposures. The data obtained from this study i) confirmed that genetic studies of viral evolution is an effective approach to detect novel in vivo HCV T-cell targets, ii) showed that HCV-specific T-cell epitopes can be recognised in their adapted form and would not have been detected using wild-type peptides and iii) showed that HCV-specific T-cell (but not antibody) responses against alternate genotypes in chronic HCV-infected subjects are readily found, implying clearance of previous alternate genotype infection. In summary, HCV adaptation to HLA Class I-restricted T-cell responses plays a central role in anti-HCV immunity and multiple HCV genotype exposure is highly prevalent in at-risk exposure populations, which are important considerations for future vaccine design. 相似文献
85.
Chrysanthia A. Leontiou Michael D. Hadjidaniel Petros Mina Pavlos Antoniou Marios Ioannides Philippos C. Patsalis 《PloS one》2015,10(8)
Introduction
Epigenetic alterations, including DNA methylation, play an important role in the regulation of gene expression. Several methods exist for evaluating DNA methylation, but bisulfite sequencing remains the gold standard by which base-pair resolution of CpG methylation is achieved. The challenge of the method is that the desired outcome (conversion of unmethylated cytosines) positively correlates with the undesired side effects (DNA degradation and inappropriate conversion), thus several commercial kits try to adjust a balance between the two. The aim of this study was to compare the performance of four bisulfite conversion kits [Premium Bisulfite kit (Diagenode), EpiTect Bisulfite kit (Qiagen), MethylEdge Bisulfite Conversion System (Promega) and BisulFlash DNA Modification kit (Epigentek)] regarding conversion efficiency, DNA degradation and conversion specificity.Methods
Performance was tested by combining fully methylated and fully unmethylated λ-DNA controls in a series of spikes by means of Sanger sequencing (0%, 25%, 50% and 100% methylated spikes) and Next-Generation Sequencing (0%, 3%, 5%, 7%, 10%, 25%, 50% and 100% methylated spikes). We also studied the methylation status of two of our previously published differentially methylated regions (DMRs) at base resolution by using spikes of chorionic villus sample in whole blood.Results
The kits studied showed different but comparable results regarding DNA degradation, conversion efficiency and conversion specificity. However, the best performance was observed with the MethylEdge Bisulfite Conversion System (Promega) followed by the Premium Bisulfite kit (Diagenode). The DMRs, EP6 and EP10, were confirmed to be hypermethylated in the CVS and hypomethylated in whole blood.Conclusion
Our findings indicate that the MethylEdge Bisulfite Conversion System (Promega) was shown to have the best performance among the kits. In addition, the methylation level of two of our DMRs, EP6 and EP10, was confirmed. Finally, we showed that bisulfite amplicon sequencing is a suitable approach for methylation analysis of targeted regions. 相似文献86.
Glossoscolex paulistus extracellular hemoglobin (HbGp) oligomeric dissociation upon interaction with sodium dodecyl sulfate: Isothermal titration calorimetry (ITC)
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Fernanda Rosa Alves Francisco Adriano O. Carvalho José Wilson P. Carvalho Marcel Tabak 《Biopolymers》2014,101(10):1065-1076
Annelid erythrocruorins are respiratory proteins with high cooperativity and low autoxidation rates. The giant extracellular hemoglobin of the earthworm, Glossoscolex paulistus (HbGp), has a molecular mass of 3.6 MDa. In this work, isothermal titration calorimetry (ITC), together with DLS and fluorescence emission have been used to investigate the interaction of SDS with the HbGp in the oxy‐form, at pH 7.0. Our ITC and DLS results show that addition of SDS induces oxy‐HbGp oligomeric dissociation, while a small amount of protein aggregation is observed only by DLS. Moreover, the oligomeric dissociation process is favored at lower protein concentrations. The temperature effect does not influence significantly the interaction of SDS with the hemoglobin, due to the similarities presented by the critical aggregation concentration (cac) and critical micelle concentration (cmc′) for the mixtures. The increase of oxy‐HbGp concentration leads to a slight variation of the cac values for the SDS‐oxy‐HbGp mixture, attributed mainly to the noncooperative electrostatic binding of surfactant to protein. However, the cmc′ values increase considerably, associated to a more cooperative hydrophobic binding. Complementary pyrene fluorescence emission studies show formation of pre‐micellar structures of the mixture already at lower SDS concentrations. This study opens the possibility of the evaluation of the surfactant effect on the hemoglobin stability by ITC, which is made for the first time with this extracellular hemoglobin. © 2014 Wiley Periodicals, Inc. Biopolymers 101: 1065–1076, 2014. 相似文献
87.
The advances of next-generation sequencing technology have facilitated metagenomics research that attempts to determine directly the whole collection of genetic material within an environmental sample (i.e. the metagenome). Identification of genes directly from short reads has become an important yet challenging problem in annotating metagenomes, since the assembly of metagenomes is often not available. Gene predictors developed for whole genomes (e.g. Glimmer) and recently developed for metagenomic sequences (e.g. MetaGene) show a significant decrease in performance as the sequencing error rates increase, or as reads get shorter. We have developed a novel gene prediction method FragGeneScan, which combines sequencing error models and codon usages in a hidden Markov model to improve the prediction of protein-coding region in short reads. The performance of FragGeneScan was comparable to Glimmer and MetaGene for complete genomes. But for short reads, FragGeneScan consistently outperformed MetaGene (accuracy improved ∼62% for reads of 400 bases with 1% sequencing errors, and ∼18% for short reads of 100 bases that are error free). When applied to metagenomes, FragGeneScan recovered substantially more genes than MetaGene predicted (>90% of the genes identified by homology search), and many novel genes with no homologs in current protein sequence database. 相似文献
88.
Changes of external morphological characters in three forms (morphotypes) of African barbs from Lake Tana (Ethiopia) belonging
to Barbus intermedius complex were traced using electronic tags. It was shown that within age interval from two to four years individual ontogenetic
allometric curves often cannot be described with a single power function equation. Individual ontogenetic trajectories in
the principal components space within this interval strongly differ in shape meandering within ontogenetic channels outlined
on the basis of cross-sectional data. Morphological differences between siblings are found that do not allow to classify some
of them with the morphotype of their parents. 相似文献
89.
John G. Mina Jackie A. Mosely Hayder Z. Ali Hosam Shams-Eldin Ralph T. Schwarz Patrick G. Steel Paul W. Denny 《The international journal of biochemistry & cell biology》2010,42(9):1553-1561
Sphingolipids are key components of eukaryotic membranes, particularly the plasma membrane. The biosynthetic pathway for the formation of these lipid species is largely conserved. However, in contrast to mammals, which produce sphingomyelin, organisms such as the pathogenic fungi and protozoa synthesize inositol phosphorylceramide (IPC) as the primary phosphosphingolipid. The key step involves the reaction of ceramide and phosphatidylinositol catalysed by IPC synthase, an essential enzyme with no mammalian equivalent encoded by the AUR1 gene in yeast and recently identified functional orthologues in the pathogenic kinetoplastid protozoa. As such this enzyme represents a promising target for novel anti-fungal and anti-protozoal drugs. Given the paucity of effective treatments for kinetoplastid diseases such as leishmaniasis, there is a need to characterize the protozoan enzyme. To this end a fluorescent-based cell-free assay protocol in a 96-well plate format has been established for the Leishmania major IPC synthase. Using this system the kinetic parameters of the enzyme have been determined as obeying the double displacement model with apparent Vmax = 2.31 pmol min?1 U?1. Furthermore, inhibitory substrate analogues have been identified. Importantly this assay is amenable to development for use in high-throughput screening applications for lead inhibitors and as such may prove to be a pivotal tool in drug discovery. 相似文献
90.
K. F. Dzerzhinskii F. N. Shkil Belay Abdissa Wondie Zelalem M. V. Mina 《Journal of Ichthyology》2007,47(8):639-646
Direct observations on three forms (morph types) of spawning barbs, considered by some authors as different species, were
carried out in September–October 2005 at the Gumara River and its small tributary, the Ducalit, in the Lake Tana basin. The
spawning barbs were sampled using cast nets. Barbs of different morphotypes composed common spawning aggregations and were
caught together. It is likely that troutlike females mate extensively with intermedius males and, probably, with bigmouth
small-eye males. Experiments in artificial fertilization and rearing showed that, during the embryonic period, there was no
increase in mortality of progeny from crosses of barbs of different morphotypes, in comparison with homonomic crosses, thus
suggesting an absence of postzygotic reproductive isolation between the morphotypes. At the same time, mortality of progeny
from crossing barbs with Varicorhinus beso Rüppell, 1836 was very high during the earliest stages of development, suggesting strong, even if incomplete, reproductive
isolation ensured by postzygotic mechanisms.
Published in Voprosy Ikhtiologii, 2007, Vol. 47, No. 5, pp. 676–683.
The article was translated by the authors. 相似文献