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51.
The importance of high-throughput analyses of protein abundances and functions is interestingly increasing in genomic/proteomic studies. In such postgenome sequencing era, a protein-detecting chip, in which a large number of molecules specifically capturing target proteins (capturing agents) such as antibodies, recombinant proteins, and small molecules are arrayed onto solid, wet, or semi-wet substrates, enables comprehensive analysis of proteomes by a single experiment. However, whole proteomes are generally complicated for comprehensive analyses so that alternative approaches to subproteome analysis categorized by protein functions and binding properties (focused proteome) would be effective. Approaching the goal of development of designed peptide chip for protein analysis, diversity increases in peptide structures and validation of target proteins are needed. We herein describe design and synthesis of nucleobase amino acid (NBA)-containing peptides, selection of nucleic acid-related proteins derived from S. cerevisiae, and detection of interactions between NBA-containing peptides and T7 phages displaying proteins by both enzyme-linked immunosorbent assays (ELISA) and label-free anomalous reflection of gold (AR) measurements. Twenty-eight phage clones were obtained by the phage-display method and sequenced. Ten of 28 clones were expected to be nucleic acid-related proteins including initiation factor, TYB protein, ribosomal proteins, elongation factor, ATP synthase subunit, GTP-binding protein, and ribonuclease. Other phage clones encoded several classes of enzymes such as reductase, oxidase, aldolase, metalloprotease, and hexokinase. Both ELISA and AR measurements suggested that the methodology of in vitro selection for recognition of the NBA-containing peptide presented in this study was successfully established. Such a combination of NBA and phage display technologies would be potential to efficiently confirm valuable target proteins binding specifically to capturing agents, to be arrayed onto solid surfaces to develop the designed peptide chip.  相似文献   
52.
Objectives: The effect of national exercise recommendations on adiposity is unknown and may differ by sex. We examined long‐term effects of aerobic exercise on adiposity in women and men. Research Methods and Procedures: This was a 12‐month randomized, controlled clinical trial testing exercise effect on weight and body composition in men (N = 102) and women (N = 100). Sedentary/unfit persons, 40 to 75 years old, were recruited through physician practices and media. The intervention was facility‐ and home‐based moderate‐to‐vigorous intensity aerobic activity, 60 min/d, 6 days/wk vs. controls (no intervention). Results: Exercisers exercised a mean 370 min/wk (men) and 295 min/wk (women), and seven dropped the intervention. Exercisers lost weight (women, ?1.4 vs. +0.7 kg in controls, p = 0.008; men, ?1.8 vs. ?0.1 kg in controls, p = 0.03), BMI (women, ?0.6 vs. +0.3 kg/m2 in controls, p = 0.006; men, ?0.5 kg/m2 vs. no change in controls, p = 0.03), waist circumference (women, ?1.4 vs. +2.2 cm in controls, p < 0.001; men, ?3.3 vs. ?0.4 cm in controls, p = 0.003), and total fat mass (women, ?1.9 vs. +0.2 kg in controls, p = 0.001; men, ?3.0 vs. +0.2 kg in controls, p < 0.001). Exercisers with greater increases in pedometer‐measured steps per day had greater decreases in weight, BMI, body fat, and intra‐abdominal fat (all p trend < 0.05 in both men and women). Similar trends were observed for increased minutes per day of exercise and for increases in maximal oxygen consumption. Discussion: These data support the U.S. Department of Agriculture and Institute of Medicine guidelines of 60 min/d of moderate‐to‐vigorous physical activity.  相似文献   
53.
54.
Here, we present the first sclerochronological investigation of shells of the gigantic inoceramids Sphenoceramus schmidti and S. sachalinensis from the middle Campanian cold seep carbonate‐bearing strata of the Yezo Basin in Hokkaido (northern Japan). Stable carbon (δ13C) and oxygen (δ18O) isotope values were measured in the aragonitic and calcitic shell layers of both species and compared to those of other co‐occurring benthic (mainly bivalves and gastropods) and demersal molluscs (ammonites). Sedimentological and stable isotope data suggest that these bivalves lived near cold seeps and were exposed to high H2S level in the seawater. The inoceramid shells exhibited higher δ13C and lower δ18O values than the coeval non‐cold seep molluscs. We ascribed the anomalous isotopic pattern to a combination of vital and environmental effects determined by the hosting of chemosymbionts and the exposure to warm interstitial waters. Inoceramid δ13C minima coincided with growth lines and likely reflect changes in nutrient supply by the chemosymbionts. Absolute temperatures estimated from δ18O values of Sphenoceramus schmidti and S. sachalinensis were, on average, ca. 4–5°C warmer than those reconstructed for the non‐seepage environment (19.3 ± 0.7°C). Short‐term δ18O fluctuations of the inoceramid material indicate local temperature ranges of up to 5.2°C, that is four times larger than those reconstructed from the benthic and demersal fauna (1.3°C). In general, our data suggest that the stable carbon and oxygen isotope values of the studied Sphenoceramus spp. were strongly affected by short‐term fluctuations in seepage activity and do not reflect seasonal fluctuations.  相似文献   
55.
Biological systems process information under noisy environment. Sensory adaptation model of E. coli is suitable for investigation because of its simplicity. To understand the adaptation processing quantitatively, stochastic thermodynamic approach has been attempted. Information processing can be assumed as state transition of a system that consists of signal transduction molecules using thermodynamic approach, and efficiency can be measured as thermodynamic cost. Recently, using information geometry and stochastic thermodynamics, a relationship between speed of the transition and the thermodynamic cost has been investigated for a chemical reaction model. Here, we introduce this approach to sensory adaptation model of E. coli, and examined a relationship between adaptation speed and the thermodynamic cost, and efficiency of the adaptation speed. For increasing external noise level in stimulation, the efficiency decreased, but the efficiency was highly robust to external stimulation strength. Moreover, we demonstrated that there is the best noise to achieve the adaptation in the aspect of thermodynamic efficiency. Our quantification method provides a framework to understand the adaptation speed and the thermodynamic cost for various biological systems.  相似文献   
56.
Genome editing can introduce designed mutations into a target genomic site. Recent research has revealed that it can also induce various unintended events such as structural variations, small indels, and substitutions at, and in some cases, away from the target site. These rearrangements may result in confounding phenotypes in biomedical research samples and cause a concern in clinical or agricultural applications. However, current genotyping methods do not allow a comprehensive analysis of diverse mutations for phasing and mosaic variant detection. Here, we developed a genotyping method with an on-target site analysis software named Determine Allele mutations and Judge Intended genotype by Nanopore sequencer (DAJIN) that can automatically identify and classify both intended and unintended diverse mutations, including point mutations, deletions, inversions, and cis double knock-in at single-nucleotide resolution. Our approach with DAJIN can handle approximately 100 samples under different editing conditions in a single run. With its high versatility, scalability, and convenience, DAJIN-assisted multiplex genotyping may become a new standard for validating genome editing outcomes.

Genome editing can introduce designed mutations into a target genomic site, but also into unintended off-target sites. DAJIN, a novel nanopore sequencing data analysis tool, identifies and quantifies allele numbers and their mutation patterns, reporting consensus sequences and visualizing mutations in alleles at single-nucleotide resolution.  相似文献   
57.
MIG-seq (Multiplexed inter-simple sequence repeats genotyping by sequencing) has been developed as a low cost genotyping technology, although the number of polymorphisms obtained is assumed to be minimal, resulting in the low application of this technique to analyses of agricultural plants. We applied MIG-seq to 12 plant species that include various crops and investigated the relationship between genome size and the number of bases that can be stably sequenced. The genome size and the number of loci, which can be sequenced by MIG-seq, are positively correlated. This is due to the linkage between genome size and the number of simple sequence repeats (SSRs) through the genome. The applicability of MIG-seq to population structure analysis, linkage mapping, and quantitative trait loci (QTL) analysis in wheat, which has a relatively large genome, was further evaluated. The results of population structure analysis for tetraploid wheat showed the differences among collection sites and subspecies, which agreed with previous findings. Additionally, in wheat biparental mapping populations, over 3,000 SNPs/indels with low deficiency were detected using MIG-seq, and the QTL analysis was able to detect recognized flowering-related genes. These results revealed the effectiveness of MIG-seq for genomic analysis of agricultural plants with large genomes, including wheat.  相似文献   
58.
An high-performance liquid chromatographic method with post-column derivatization has been developed for the simultaneous determination of ascorbic acid (AA) and dehydroascorbic acid (DHAA) in fish tissues. Extracted AA and DHAA were separated by a Shim-pack SCR-101H column within 20 min, reacted with sodium hydroxide containing sodium borohydride and monitored at 300 nm. The detection limits for both AA and DHAA were 0.1 μg/ml.  相似文献   
59.
The proliferation of oligodendrocyte lineage cells in the chick embryo central nervous system (CNS) was examined by double-immunolabeling with a lineage marker monoclonal antibody (mAb) O4 or mAb O1 and 5-bromo-3'-deoxyuridine (BrdU). In all regions examined, the first O4-positive (O4+) cells appeared in restricted regions of the ventricular zone (VZ), regarded as a site of oligodendrocyte origin. Within the O4+ focus, less than 20% of the O4+ cells incorporated BrdU. In contrast, O4+ cells in the parenchyma were mitotically active; for example, 40-50% of early O4+ cells were labeled with BrdU. Some of these were unipolar in shape, indicative of migratory precursor cells. The frequency of O4+/BrdU+ cell appearance decreased to less than 20% with further development. O1+ oligodendrocytes were largely mitotically inactive, with only approximately 5% of O1+ cells incorporating BrdU. These results clearly demonstrated that the VZ generates relatively few precursor cells and that these oligodendrocyte precursors actively generate their cohort in the parenchyma of the CNS.  相似文献   
60.
The larva of the privet moth, Brahmaea wallichii (Brahmaeidae) is a specialist feeder of the privet tree, Ligustrum obtusifolium (Oleaceae). A very high concentration (50 mM or 0.4%) of free glycine, found in the digestive juice of the larvae, works as a neutralizer against the very strong protein-denaturing activity of privet leaves that is caused by oleuropein, an iridoid that functions in chemical defense. Concentration of free glycine was high in the anterior region of the midgut lumen and low in the posterior region. To examine if some glycine-specific secretion mechanism exists, injection experiments were performed using (15)N-labeled amino acids. When 13 &mgr;mol (1 mg) of (15)N-glycine was injected into hemolymph of fifth instar larvae of B. wallichii, a high concentration of (15)N (5 mM or 75 &mgr;g/g midgut content) was detected in the anterior parts of the midgut lumen 1 h after injection. (15)N-NMR data indicated at least 60% of the (15)N found in midgut lumen existed as (15)N-glycine. Approximately, 25% of the injected (15)N-glycine was estimated to have moved from the hemolymph to the midgut lumen. In contrast, no (15)N was detected in the midgut lumen when 13 &mgr;mol of (15)N-labeled alanine, lysine and glutamate were injected into hemolymph. Glycine was the only amino acid whose concentration was higher in the midgut lumen (50 mM) than in the hemolymph (22 mM). These data suggest the existence of some active and glycine-specific secretory mechanism in the midgut of B. wallichii.  相似文献   
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