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961.
962.
Scaramuzzo L Perisano C Leone A Graci C Spinelli MS Di Giacomo G Venanzi E Schiavone Panni A Maccauro G 《Journal of biological regulators and homeostatic agents》2012,26(1):139-144
The mucopolysaccharidoses (MPS) are a group of rare diseases characterized by deficiencies in different enzymes required for degradation of complex carbohydrates. The enzymatic deficiencies lead to lysosomal accumulation of dermatan sulphate, heparan sulphate, and keratan sulphate in different tissue resulting in multi-system complications. Six different principal types are described. Most MPS types, with the exception of MPS III, are associated with widespread skeletal abnormalities and joint disease. Authors analyzed clinical pathological and radiographical features of mucopolysaccharidoses focusing on pelvic and spine pathologies that generally limit activity and normal life so they have to be treated at the beginning of their manifestations in order to avoid major complication and improve quality of life. 相似文献
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964.
The problem of cell totipotency,dedifferentiation and transdifferentiation in Turbellaria 总被引:1,自引:7,他引:1
Vittorio Gremigni 《Hydrobiologia》1981,84(1):171-179
965.
Inflammation, genetics, and ischemic heart disease: focus on the major histocompatibility complex (MHC) genes 总被引:4,自引:0,他引:4
BACKGROUND: Increasing data suggest that ischemic heart disease (IHD) shares several characteristics with common inflammatory diseases (such as rheumatoid arthritis), in which the pathogenetic role of inflammatory gene polymorphisms is well established. Variants in the genes for the major histocompatibility complex (MHC) molecules on the short arm of chromosome 6 show profound "linkage disequilibrium", leading to the formation of "haplotypes", i.e., frozen blocks of alleles travelling together through generations. DESIGN: We performed a review of published studies linking IHD with gene polymorphisms of the MHC molecules tumor necrosis factor (TNF)-alpha and -beta, the class II DR human leukocyte antigens, heat shock protein 70-1, hemochromatosis related gene, and complement C4. RESULTS: The emerging data are quite conflicting and do not provide definitive evidence for a role of these gene variants in the pathogenesis of IHD; a possible exception is the G252A and polymorphism in the TNF-beta gene (also known as lymphotoxin-alpha) which, in a comprehensive genome-scan linkage analysis of unrelated Japanese, but not in a smaller German population, was linked to myocardial infarction. However, some important biases appear, e.g. different study design and variable linkage disequilibrium among different populations. CONCLUSIONS: Preliminary positive results should encourage future studies to focus on clinical models of IHD with well-codified inflammatory components, using novel methods (such as haplotype analysis) to assess gene polymorphisms and their clinical effect. 相似文献
966.
High-Throughput MicroRNA (miRNAs) Arrays Unravel the Prognostic Role of MiR-211 in Pancreatic Cancer
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968.
A Marchetti M Del Grammastro G Filice L Felicioni G Rossi P Graziano G Sartori A Leone S Malatesta M Iacono L Guetti P Viola F Mucilli F Cuccurullo F Buttitta 《PloS one》2012,7(7):e42164
Microdeletions at exon 19 are the most frequent genetic alterations affecting the Epidermal Growth Factor Receptor (EGFR) gene in non-small cell lung cancer (NSCLC) and they are strongly associated with response to treatment with tyrosine kinase inhibitors. A series of 116 NSCLC DNA samples investigated by Sanger Sequencing (SS), including 106 samples carrying exon 19 EGFR deletions and 10 without deletions (control samples), were subjected to deep next generation sequencing (NGS). All samples with deletions at SS showed deletions with NGS. No deletions were seen in control cases. In 93 (88%) cases, deletions detected by NGS were exactly corresponding to those identified by SS. In 13 cases (12%) NGS resolved deletions not accurately characterized by SS. In 21 (20%) cases the NGS showed presence of complex (double/multiple) frameshift deletions producing a net in-frame change. In 5 of these cases the SS could not define the exact sequence of mutant alleles, in the other 16 cases the results obtained by SS were conventionally considered as deletions plus insertions. Different interpretative hypotheses for complex mutations are discussed. In 46 (43%) tumors deep NGS showed, for the first time to our knowledge, subpopulations of DNA molecules carrying EGFR deletions different from the main one. Each of these subpopulations accounted for 0.1% to 17% of the genomic DNA in the different tumors investigated. Our findings suggest that a region in exon 19 is highly unstable in a large proportion of patients carrying EGFR deletions. As a corollary to this study, NGS data were compared with those obtained by immunohistochemistry using the 6B6 anti-mutant EGFR antibody. The immunoreaction was E746-A750del specific. In conclusion, NGS analysis of EGFR exon 19 in NSCLCs allowed us to formulate a new interpretative hypothesis for complex mutations and revealed the presence of subpopulations of deletions with potential pathogenetic and clinical impact. 相似文献
969.
The lexicons of human languages organize their units at two distinct levels. At a first combinatorial level, meaningless forms (typically referred to as phonemes) are combined into meaningful units (typically referred to as morphemes). Thanks to this, many morphemes can be obtained by relatively simple combinations of a small number of phonemes. At a second compositional level of the lexicon, morphemes are composed into larger lexical units, the meaning of which is related to the individual meanings of the composing morphemes. This duality of patterning is not a necessity for lexicons and the question remains wide open regarding how a population of individuals is able to bootstrap such a structure and the evolutionary advantages of its emergence. Here we address this question in the framework of a multi-agents model, where a population of individuals plays simple naming games in a conceptual environment modeled as a graph. We demonstrate that errors in communication as well as a blending repair strategy, which crucially exploits a shared conceptual representation of the environment, are sufficient conditions for the emergence of duality of patterning, that can thus be explained in a pure cultural way. Compositional lexicons turn out to be faster to lead to successful communication than purely combinatorial lexicons, suggesting that meaning played a crucial role in the evolution of language. 相似文献
970.