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211.
Lidwien AM Smit Manolis Kogevinas Josep M Ant�� Emmanuelle Bouzigon Juan Ram��n Gonz��lez Nicole Le Moual Hans Kromhout Anne-Elie Carsin Isabelle Pin Deborah Jarvis Roel Vermeulen Christer Janson Joachim Heinrich Ivo Gut Mark Lathrop Miguel A Valverde Florence Demenais Francine Kauffmann 《Respiratory research》2012,13(1):26
Background
Transient receptor potential (TRP) vanilloid and ankyrin cation channels are activated by various noxious chemicals and may play an important role in the pathogenesis of cough. The aim was to study the influence of single nucleotide polymorphisms (SNPs) in TRP genes and irritant exposures on cough.Methods
Nocturnal, usual, and chronic cough, smoking, and job history were obtained by questionnaire in 844 asthmatic and 2046 non-asthmatic adults from the Epidemiological study on the Genetics and Environment of Asthma (EGEA) and the European Community Respiratory Health Survey (ECRHS). Occupational exposures to vapors, gases, dusts, and/or fumes were assessed by a job-exposure matrix. Fifty-eight tagging SNPs in TRPV1, TRPV4, and TRPA1 were tested under an additive model.Results
Statistically significant associations of 6 TRPV1 SNPs with cough symptoms were found in non-asthmatics after correction for multiple comparisons. Results were consistent across the eight countries examined. Haplotype-based association analysis confirmed the single SNP analyses for nocturnal cough (7-SNP haplotype: p-global = 4.8 × 10-6) and usual cough (9-SNP haplotype: p-global = 4.5 × 10-6). Cough symptoms were associated with exposure to irritants such as cigarette smoke and occupational exposures (p < 0.05). Four polymorphisms in TRPV1 further increased the risk of cough symptoms from irritant exposures in asthmatics and non-asthmatics (interaction p < 0.05).Conclusions
TRPV1 SNPs were associated with cough among subjects without asthma from two independent studies in eight European countries. TRPV1 SNPs may enhance susceptibility to cough in current smokers and in subjects with a history of workplace exposures. 相似文献212.
BLM and SLX4 play opposing roles in recombination‐dependent replication at human telomeres 下载免费PDF全文
Alexander P Sobinoff Joshua AM Allen Axel A Neumann Sile F Yang Monica E Walsh Jeremy D Henson Roger R Reddel Hilda A Pickett 《The EMBO journal》2017,36(19):2907-2919
Alternative lengthening of telomeres (ALT) is a telomere lengthening pathway that predominates in aggressive tumors of mesenchymal origin; however, the underlying mechanism of telomere synthesis is not fully understood. Here, we show that the BLM–TOP3A–RMI (BTR) dissolvase complex is required for ALT‐mediated telomere synthesis. We propose that recombination intermediates formed during strand invasion are processed by the BTR complex, initiating rapid and extensive POLD3‐dependent telomere synthesis followed by dissolution, with no overall exchange of telomeric DNA. This process is counteracted by the SLX4–SLX1–ERCC4 complex, which promotes resolution of the recombination intermediate, resulting in telomere exchange in the absence of telomere extension. Our data are consistent with ALT being a conservative DNA replication process, analogous to break‐induced replication, which is dependent on BTR and counteracted by SLX4 complex‐mediated resolution events. 相似文献
213.
John WM Bastiaansen Albart Coster Mario PL Calus Johan AM van Arendonk Henk Bovenhuis 《遗传、选种与进化》2012,44(1):3
Background
Genomic selection has become an important tool in the genetic improvement of animals and plants. The objective of this study was to investigate the impacts of breeding value estimation method, reference population structure, and trait genetic architecture, on long-term response to genomic selection without updating marker effects.Methods
Three methods were used to estimate genomic breeding values: a BLUP method with relationships estimated from genome-wide markers (GBLUP), a Bayesian method, and a partial least squares regression method (PLSR). A shallow (individuals from one generation) or deep reference population (individuals from five generations) was used with each method. The effects of the different selection approaches were compared under four different genetic architectures for the trait under selection. Selection was based on one of the three genomic breeding values, on pedigree BLUP breeding values, or performed at random. Selection continued for ten generations.Results
Differences in long-term selection response were small. For a genetic architecture with a very small number of three to four quantitative trait loci (QTL), the Bayesian method achieved a response that was 0.05 to 0.1 genetic standard deviation higher than other methods in generation 10. For genetic architectures with approximately 30 to 300 QTL, PLSR (shallow reference) or GBLUP (deep reference) had an average advantage of 0.2 genetic standard deviation over the Bayesian method in generation 10. GBLUP resulted in 0.6% and 0.9% less inbreeding than PLSR and BM and on average a one third smaller reduction of genetic variance. Responses in early generations were greater with the shallow reference population while long-term response was not affected by reference population structure.Conclusions
The ranking of estimation methods was different with than without selection. Under selection, applying GBLUP led to lower inbreeding and a smaller reduction of genetic variance while a similar response to selection was achieved. The reference population structure had a limited effect on long-term accuracy and response. Use of a shallow reference population, most closely related to the selection candidates, gave early benefits while in later generations, when marker effects were not updated, the estimation of marker effects based on a deeper reference population did not pay off. 相似文献214.
Assessing horizontal transfer of nifHDK genes in eubacteria: nucleotide sequence of nifK from Frankia strain HFPCcI3 总被引:1,自引:1,他引:1
Hirsch AM; McKhann HI; Reddy A; Liao J; Fang Y; Marshall CR 《Molecular biology and evolution》1995,12(1):16-27
The structural genes for nitrogenase, nifK, nifD, and nifH, are crucial for
nitrogen fixation. Previous phylogenetic analysis of the amino acid
sequence of nifH suggested that this gene had been horizontally transferred
from a proteobacterium to the gram-positive/cyanobacterial clade, although
the confounding effects of paralogous comparisons made interpretation of
the data difficult. An additional test of nif gene horizontal transfer
using nifD was made, but the NifD phylogeny lacked resolution. Here nif
gene phylogeny is addressed with a phylogenetic analysis of a third and
longer nif gene, nifK. As part of the study, the nifK gene of the key taxon
Frankia was sequenced. Parsimony and some distance analyses of the nifK
amino acid sequences provide support for vertical descent of nifK, but
other distance trees provide support for the lateral transfer of the gene.
Bootstrap support was found for both hypotheses in all trees; the nifK data
do not definitively favor one or the other hypothesis. A parsimony analysis
of NifH provides support for horizontal transfer in accord with previous
reports, although bootstrap analysis also shows some support for vertical
descent of the orthologous nifH genes. A wider sampling of taxa and more
sophisticated methods of phylogenetic inference are needed to understand
the evolution of nif genes. The nif genes may also be powerful phylogenetic
tools. If nifK evolved by vertical descent, it provides strong evidence
that the cyanobacteria and proteobacteria are sister groups to the
exclusion of the firmicutes, whereas 16S rRNA sequences are unable to
resolve the relationships of these three major eubacterial lineages.
相似文献
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218.
Background
Pelodera (Rhabditis) strongyloides is a small saprophytic nematode that lives in decaying organic matter. On rare occasions, it can invade the mammalian skin, causing a pruritic, erythematous, alopecic and crusting dermatitis on skin sites that come into contact with the ground. Diagnosis of the disease is based on case history (a dog living outdoors on damp straw bedding) with characteristic skin lesions and on the demonstration of typical larvae in skin scrapings or biopsy. Pelodera (rhabditic) dermatitis cases have been reported mainly from Central European countries and the United States. 相似文献219.
Bases and spaces: resources on the web for accessing the draft human genome - II - After publication of the draft 下载免费PDF全文
Colin AM Semple 《Genome biology》2001,2(6):reviews2001.1-reviews20016
The volume of human genome sequence and the variety of web-based tools to access it continue to grow at an impressive rate, but a working knowledge of certain key resources can be sufficient to get the most from your genome. This article provides an update to Genome Biology 2000, 1(4):reviews2001.1-2001.5. 相似文献