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81.
82.
Epigenetics refers to a set of regulatory mechanisms that affect gene expression, while the original sequence of the DNA remains unchanged. Because the advance of noncoding RNAs (ncRNAs), the role of microRNAs (miRNAs) has been gradually highlighted in the regulation of numerous cellular processes. A bulk of studies has identified that ncRNAs might be divided into several subtypes. On the one hand, investigations have disclosed the role of these molecules in normal physiological conditions of the cells. On the other hand, there is sufficient evidence that ncRNAs participate in the pathogenesis of diseases. Through this review article, we attempted to gain a comprehensive understanding of the role of ncRNAs, long ncRNAs, miRNAs, and other subtypes in pathogenesis, diagnosis, and treatment of rheumatoid arthritis (RA). Research demonstrated aberrant expression of several miRNAs in various cell and tissue types of patients with RA in comparison to the healthy individuals as well as in animal studies. Furthermore, plausible molecular mechanisms of alterations in ncRNAs expression has been discussed in causing the disease state. These alterations seem promising to be used as biomarkers in RA diagnosis. Alternately, they might be targeted by drugs to interrupt inflammation and other disease complications to treat patients with RA.  相似文献   
83.

Maximizing the number of offspring born per female is a key functionality trait in commercial- and/or subsistence-oriented livestock enterprises. Although the number of offspring born is closely associated with female fertility and reproductive success, the genetic control of these traits remains poorly understood in sub-Saharan Africa livestock. Using selection signature analysis performed on Ovine HD BeadChip data from the prolific Bonga sheep in Ethiopia, 41 candidate regions under selection were identified. The analysis revealed one strong selection signature on a candidate region on chromosome X spanning BMP15, suggesting this to be the primary candidate prolificacy gene in the breed. The analysis also identified several candidate regions spanning genes not reported before in prolific sheep but underlying fertility and reproduction in other species. The genes associated with female reproduction traits included SPOCK1 (age at first oestrus), GPR173 (mediator of ovarian cyclicity), HB-EGF (signalling early pregnancy success) and SMARCAL1 and HMGN3a (regulate gene expression during embryogenesis). The genes involved in male reproduction were FOXJ1 (sperm function and successful fertilization) and NME5 (spermatogenesis). We also observed genes such as PKD2L2, MAGED1 and KDM3B, which have been associated with diverse fertility traits in both sexes of other species. The results confirm the complexity of the genetic mechanisms underlying reproduction while suggesting that prolificacy in the Bonga sheep, and possibly African indigenous sheep is partly under the control of BMP15 while other genes that enhance male and female fertility are essential for reproductive fitness.

  相似文献   
84.
Plant pathogenic fungi of the genus Fusarium can cause severe diseases on small grain cereals and maize. The contamination of harvested grain with Fusarium mycotoxins is a threat to human and animal health. In wheat production of the toxin deoxynivalenol (DON), which inhibits eukaryotic protein biosynthesis, is a virulence factor of Fusarium, and resistance against DON is considered to be part of Fusarium resistance. Previously, single amino acid changes in RPL3 (ribosomal protein L3) conferring DON resistance have been described in yeast. The goal of this work was to characterize the RPL3 gene family from wheat and to investigate the potential role of naturally existing RPL3 alleles in DON resistance by comparing Fusarium-resistant and susceptible cultivars. The gene family consists of three homoeologous alleles of both RPL3A and RPL3B, which are located on chromosomes 4A (RPL3-B2), 4B (RPL3-B1), 4D (RPL3-B3), 5A (RPL3-A3), 5B (RPL3-A2) and 5D (RPL3-A1). Alternative splicing was detected in the TaRPL3-A2 gene. Sequence comparison revealed no amino acid differences between cultivars differing in Fusarium resistance. While using developed SNP markers we nevertheless found that one of the genes, namely, TaRPL3-A3 mapped close to a Fusarium resistance QTL (Qfhs.ifa-5A). The potential role of the RPL3 gene family in DON resistance of wheat is discussed.  相似文献   
85.
The pathway to reach a certain target in many processes such as bioleaching, due to the complex and poorly understood hydrodynamics, reaction kinetics, and chemistry knowledge involved is not apparent. An investigation of the interactions between the parameters in bioleaching process can be applied to optimize the rate of metal extraction from sulphide minerals. Such investigations can be carried out with the aid of numerical simulations. In this study, a computational fluid dynamics (CFD) model was developed to better understand the mass transfer phenomenon and complex flow field around a single particle. The commercial software FLUENT 6.2 has been employed to solve the governing equations. Volume of fluid (VOF) method was used to predict the fluid volume fraction in a 3D geometry. The computational model has successfully captured the results observed in the experiments. Simulation results indicate that concentrations of species in a thin layer of liquid on the particle surface are much higher than their concentrations in the liquid bulk and significant gradients in the ion concentrations between the surface of the particle and the liquid bulk were observed.  相似文献   
86.
New ammonoid species of the genus Araxoceras (A. abarquense sp. nov. and A. iranense sp. nov.) are described from the Early Dzhulfian (Early Wuchiapingian) beds of the Hambast Formation of Central Iran (Abade). The data on the distribution of Paraceltites (Paraceltites sp.) and Vedioceras (V. umbonovarum Ruzhencev), for the first time discovered in the Dzhulfian beds of Abade, and of Eoaraxoceras are provided. The correlation of the Late Permian assemblages of ammonoids of Iran and Transcaucasia is amended.  相似文献   
87.
Biomechanics and Modeling in Mechanobiology - Evolution of mechanical and structural properties in the Ascending Thoracic Aorta (ATA) is the results of complex mechanobiological processes. In this...  相似文献   
88.
Journal of Applied Phycology - This study assessed a culture system using a static magnetic field (SMF) for improving biomass and astaxanthin production in Haematococcus lacustris. Different...  相似文献   
89.
International Journal of Peptide Research and Therapeutics - The aim of this experiment was to evaluate the effects of bioactive peptides derived from sesame meal (BPSM) compared with...  相似文献   
90.
Bradyrhizobia are common members of soil microbiomes and known as N2-fixing symbionts of economically important legumes. Many are also denitrifiers, which can act as sinks or sources for N2O. Inoculation with compatible rhizobia is often needed for optimal N2-fixation, but the choice of inoculant may have consequences for N2O emission. Here, we determined the phylogeny and denitrification capacity of Bradyrhizobium strains, most of them isolated from peanut-nodules. Analyses of genomes and denitrification end-points showed that all were denitrifiers, but only ~1/3 could reduce N2O. The N2O-reducing isolates had strong preference for N2O- over NO3-reduction. Such preference was also observed in a study of other bradyrhizobia and tentatively ascribed to competition between the electron pathways to Nap (periplasmic NO3 reductase) and Nos (N2O reductase). Another possible explanation is lower abundance of Nap than Nos. Here, proteomics revealed that Nap was instead more abundant than Nos, supporting the hypothesis that the electron pathway to Nos outcompetes that to Nap. In contrast, Paracoccus denitrificans, which has membrane-bond NO3 reductase (Nar), reduced N2O and NO3 simultaneously. We propose that the control at the metabolic level, favouring N2O reduction over NO3 reduction, applies also to other denitrifiers carrying Nos and Nap but lacking Nar.  相似文献   
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