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911.
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913.
914.
Localization of integrins β1-8, α1, α2, α3, α5, α6 and αv in sinus endothelial cells of the rat spleen was examined by immunofluorescence microscopy. Labeling for anti-integrin β5 and integrin αv was detected and colocalized in the entire circumference of endothelial cells. Labeling for integrin β5, vinculin and actin filaments demonstrated that they lay close to each other in the basal part of the endothelial cells. Although the other integrin βs, including integrin β1 and integrins α1, α2, α3, α5 and α6 in combination with integrin β1, were localized in leukocytes, slightly large cells, megakaryocytes and/or platelets in the sinus lumen and splenic cords, they were not detected in endothelial cells. Labeling for vitronectin, a component of the extracellular-matrix-binding integrin αvβ5, was strongly stained in the periphery of the wall of sinuses, as was collagen IV and, in addition, was localized in the cytoplasm of endothelial cells. Ultrastructural localization of integrin β5, vitronectin and clathrin was examined by immunogold electron microscopy to elucidate the involvement of integrin αvβ5 in the endocytosis of vitronectin in sinus endothelial cells. Electron microscopy with detergent extraction revealed abundant coated pits and coated vesicles in endothelial cells. Immunogold labeling for vitronectin was present in pits, vesicles and the stacked endoplasmic reticulum. Double-labeling for integrin β5 or integrin αv and clathrin revealed that they were colocalized in some vesicles in close proximity to the apical and lateral plasma membrane of the endothelial cells. The possible functional roles of integrin αvβ5 in endothelial cells of the splenic sinus are discussed.  相似文献   
915.
We investigated 793 bird combs [645 chickens and 148 fighting cocks (Shamo)] to determine the prevalence of dermatophytes and their related fungal species. The targeted fungal species were recovered from 195 of the 793 examined birds (24.6 %). Prevalence ratios were compared in temperate (the mainland) and subtropical (Nansei Islands) areas, genders, strains, breeding scale (individual and farm), and housing system (in cage and free ranging). The frequency of the fungal species in the mainland, males, fighting cocks, breeding scale by individual nursing, and free-range housing system exhibited significantly higher positive ratios than that in the other groups. A total of 224 dermatophytes and related species were isolated, including 101 Arthroderma (Ar.) multifidum, 83 Aphanoascus (Ap.) terreus, five Uncinocarpus queenslandicus, two U. reesii, two Ap. pinarensis, one Amauroascus kuehnii, one Ar. simii, one Gymnoascus petalosporus, one Microsporum gallinae, and 28 Chrysosporium-like (Chrysosporium spp.) isolates, which were identified using internal transcribed spacer regions of ribosomal RNA gene sequences. The predominant fungal species in the mainland was Ap. terreus and that in the Nansei Islands was Ar. multifidum. Pathogenic fungal species to humans and animals were limited to M. gallinae and Ar. simii, which corresponded to 0.025 % of the isolates in this study.  相似文献   
916.
The application of DNA technology in forensic investigations has grown rapidly in the last 25 years and with an exponential increase of short tandem repeats (STRs) data, usually presented as allele frequencies, that may be later used as databases for forensic and population genetics purposes. Thereby, classes of molecular markers such as single nucleotide polymorphisms and insertions/deletions (InDels) have been presented as another option of genetic marker sets. These markers can be used in paternity cases, when mutations in STR polymorphisms are present, as well as in highly degraded DNA analysis. In the present study, the allele frequencies and heterozygosity (H) of a 30 InDel markers set were determined and the forensic efficacy was evaluated through estimation of discrimination power (DP), match probability, typical paternity index and power of paternity exclusion in 108 unrelated volunteers from the State of Santa Catarina (South Brazil). The observed H per locus showed a range between 0.370 and 0.574 (mean = 0.479). HLD128 was the locus with the highest DP (DP = 0.656). DP for all markers combined was greater than 99.9999999999646 % which provides satisfactory levels of information for forensic demands. Genetic comparisons (exact tests of population differentiation and pairwise genetic distances) revealed that the population of Santa Catarina State differs from Korea and USA Afro-American populations but is similar to the Portuguese, German, Polish, Spanish and Basque populations.  相似文献   
917.
Mycosporines and mycosporine-like amino acids (MAAs), including shinorine (mycosporine-glycine-serine) and porphyra-334 (mycosporine-glycine-threonine), are UV-absorbing compounds produced by cyanobacteria, fungi, and marine micro- and macroalgae. These MAAs have the ability to protect these organisms from damage by environmental UV radiation. Although no reports have described the production of MAAs and the corresponding genes involved in MAA biosynthesis from Gram-positive bacteria to date, genome mining of the Gram-positive bacterial database revealed that two microorganisms belonging to the order Actinomycetales, Actinosynnema mirum DSM 43827 and Pseudonocardia sp. strain P1, possess a gene cluster homologous to the biosynthetic gene clusters identified from cyanobacteria. When the two strains were grown in liquid culture, Pseudonocardia sp. accumulated a very small amount of MAA-like compound in a medium-dependent manner, whereas A. mirum did not produce MAAs under any culture conditions, indicating that the biosynthetic gene cluster of A. mirum was in a cryptic state in this microorganism. In order to characterize these biosynthetic gene clusters, each biosynthetic gene cluster was heterologously expressed in an engineered host, Streptomyces avermitilis SUKA22. Since the resultant transformants carrying the entire biosynthetic gene cluster controlled by an alternative promoter produced mainly shinorine, this is the first confirmation of a biosynthetic gene cluster for MAA from Gram-positive bacteria. Furthermore, S. avermitilis SUKA22 transformants carrying the biosynthetic gene cluster for MAA of A. mirum accumulated not only shinorine and porphyra-334 but also a novel MAA. Structure elucidation revealed that the novel MAA is mycosporine-glycine-alanine, which substitutes l-alanine for the l-serine of shinorine.  相似文献   
918.
Temporal variation in selection is typically evaluated by estimating and comparing selection coefficients in natural populations. Meta‐analyses of these coefficients have yielded important insights, but selection coefficients are limited in several respects, including low statistical power, imperfect fitness surrogates, and uncertainty regarding consequences for trait change. A complementary approach without these limitations is to examine temporal variation in adaptive traits themselves, which is mechanistically easier and more directly relevant to evolutionary consequences. We illustrate this approach by analyzing the colour patterns of male guppies, Poecilia reticulata, from each of six sites in Trinidad in each of 6 years. This system is particularly appropriate for our study because key aspects of colour variation are genetically‐based and responsive to selection. However, although spatial patterns of colour variation have been extensively considered in this system, no study has yet formally assessed annual temporal variation in non‐manipulated populations. Matching previous conclusions for the guppy system, we find that guppies from different sites manifest different colour patterns in association with different predation regimes. We here add the new finding that, although some temporal variation is present, spatial patterns of colour variation are generally consistent across years. These results suggest that, when considering adaptive traits, spatial variation is more important than temporal variation, although our study system might be exceptional in this regard. Additional studies examining spatiotemporal variation in adaptive traits could help to improve our understanding of the role that spatiotemporal variation in selection plays in the evolutionary process. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112 , 108–122.  相似文献   
919.
Bioinformatics approaches to carbohydrate research have recently begun using large amounts of protein and carbohydrate data. In this field called glycome informatics, the foremost necessity is a comprehensive resource for genome-scale bioinformatics analysis of glycan data. Although the accumulation of experimental data may be useful as a reference of biological and biochemical information on carbohydrates, this is insufficient for bioinformatics analysis. Thus, we have developed a glycome informatics resource (http://www.genome.jp/kegg/glycan/) in KEGG (Kyoto Encyclopedia of Genes and Genomes), an integrated knowledge base of protein networks, genomic information, and chemical information. This review describes three noteworthy features: (1) GLYCAN, a database of carbohydrate structures; (2) glycan-related pathways; and (3) Composite Structure Map (CSM), a map illustrating all possible variations of carbohydrate structures within organisms. GLYCAN includes two useful tools: an intuitive drawing tool called KegDraw, and an efficient glycan search and alignment tool called KEGG Carbohydrate Matcher (KCaM). KEGG's glycan biosynthesis and metabolism pathways, integrating carbohydrate structures, proteins, and reactions, are also a pivotal resource. CSM is constructed as a bridge between carbohydrate functions and structures. CSM is able to display, for example, expression data of glycosyltransferases in a compact manner. In all the KEGG resources, various objects including KEGG pathways, chemical compounds, as well as carbohydrate structures are commonly represented as graphs, which are widely studied and utilized in the computer science field.  相似文献   
920.
The ubiquitin system plays important roles in the regulation of numerous cellular processes by conjugating ubiquitin to target proteins. In most cases, conjugation of polyubiquitin to target proteins regulates their function. In the polyubiquitin chains reported to date, ubiquitin monomers are linked via isopeptide bonds between an internal Lys and a C-terminal Gly. Here, we report that a protein complex consisting of two RING finger proteins, HOIL-1L and HOIP, exhibits ubiquitin polymerization activity by recognizing ubiquitin moieties of proteins. The polyubiquitin chain generated by the complex is not formed by Lys linkages, but by linkages between the C- and N-termini of ubiquitin, indicating that the ligase complex possesses a unique feature to assemble a novel head-to-tail linear polyubiquitin chain. Moreover, the complex regulates the stability of Ub-GFP (a GFP fusion protein with an N-terminal ubiquitin). The linear polyubiquitin chain generated post-translationally may function as a new modulator of proteins.  相似文献   
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