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1.
G. Bucci T. L. Kubisiak W. L. Nance P. Menozzi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):643-654
We built a “consensus” partial linkage map based on RAPD markers using 48 sibships of eight megagametophytes each from a
natural population of Norway spruce. A RAPD linkage map for a single individual from the same population had previously been
constructed. Using 30 random decamers that had yielded 83 RAPD markers in the single-tree map, eight megagametophytes for
each of the 48 sibships were screened. The linkage relationship among markers was estimated considering each family of eight
megagametophytes as a progeny of a phase-unknown backcross mating between a heterozygous mother and a fictitious ‘recessive’
father. Markers were assigned to windows using LOD=2.0 and θ=0.4 as thresholds, and ordered using a criterion of interval
support ≥2.0. For eight “windows” of recombination selected on the single-tree map, we investigated the consistency of marker
order in the two maps. We adopted restrictive criteria for rejecting co-linearity between the two locus orders. For each window
we imposed the most likely locus order obtained from one data set to the other (and vice versa), obtaining two symmetrical
log-likelihood differences. We considered the hypothesis of co-linearity rejected when both symmetrical differences were significant
(ΔLOD>3.0). By bootstrapping a subset of markers for each window (highly informative, ‘framework’ loci chosen on the previous
single-tree map using a matrix correlation method) the sampling variability of the single-tree and population maps was estimated.
As expected the population map was affected by a larger variability than the single-tree map. Heterogeneity in pairwise recombination
fractions among groups of sibship revealed a (possible) alternative genomic arrangement detected within a single recombination
window.
Received : 4 January 1997 / Accepted : 24 January 1997 相似文献
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Gun E. Lee Joo Hee Kim Michael Taylor Mark T. Muller 《The Journal of biological chemistry》2010,285(48):37630-37640
Correction of double strand DNA breaks proceeds in an error-free pathway of homologous recombination (HR), which can result in gene silencing of half of the DNA molecules caused by action by DNA methyltransferase 1 (DNMT1) (Cuozzo, C., Porcellini, A., Angrisano, T., Morano, A., Lee, B., Di Pardo, A., Messina, S., Iuliano, R., Fusco, A., Santillo, M. R., Muller, M. T., Chiariotti, L., Gottesman, M. E., and Avvedimento, E. V. (2007) PLoS Genet. 3, e110). To explore the mechanism that leads to HR-induced silencing, a genetic screen was carried out based on the silencing of a GFP reporter to identify potential partners. DMAP1, a DNMT1 interacting protein, was identified as a mediator of this process. DMAP1 is a potent activator of DNMT1 methylation in vitro, suggesting that DMAP1 is a co-repressor that supports the maintenance and de novo action of DNMT1. To examine critical roles for DMAP1 in vivo, lentiviral shRNA was used to conditionally reduce cellular DMAP1 levels. The shRNA transduced cells grew poorly and eventually ceased their growth. Analysis of the tumor suppressor gene p16 methylation status revealed a clear reduction in methylated CpGs in the shRNA cells, suggesting that reactivation of a tumor suppressor gene pathway caused the slow growth phenotype. Analysis of HR, using a fluorescence-based reporter, revealed that knocking down DMAP1 also caused hypomethylation of the DNA repair products following gene conversion. DMAP1 was selectively enriched in recombinant GFP chromatin based on chromatin immunoprecipitation analysis. The picture that emerges is that DMAP1 activates DNMT1 preferentially at sites of HR repair. Because DMAP1 depleted cells display enhanced HR, we conclude that it has additional roles in genomic stability. 相似文献
4.
In searching for differentially expressed genes in human uterine leiomyomas (ULs), suppression sub-tractive hybridization was used to construct an UL up-regulated library, which turned out to represent 88genes. After two rounds of screening by reverse Northern analysis, twenty genes were proved to be up-regulated, including seventeen known genes and three genes with unknown function. All these genes werefirstly associated with UL. Three genes with notable difference were selected for Northern confirmationOur results proved the authenticity of the twenty genes. One gene named Phospholipase A2 (PLA2) showedup-regulation in 4/6 of the patients and investigation of tissue distribution indicated that it had obviousexpression in prostate, testis, liver, heart and skeletal muscle. 相似文献
5.
A maize bacterial artificial chromosome (BAC) library from the European flint inbred line F2 总被引:2,自引:0,他引:2
D. M. O’Sullivan P. J. Ripoll M. Rodgers K. J. Edwards 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(2-3):425-432
We report here the construction and characterisation of a BAC library from the maize flint inbred line F2, widely used in
European maize breeding programs. The library contains 86,858 clones with an average insert size of approximately 90 kb, giving
approximately 3.2-times genome coverage. High-efficiency BAC cloning was achieved through the use of a single size selection
for the high-molecular-weight genomic DNA, and co-transformation of the ligation with yeast tRNA to optimise transformation
efficiency. Characterisation of the library showed that less than 0.5% of the clones contained no inserts, while 5.52% of
clones consisted of chloroplast DNA. The library was gridded onto 29 nylon filters in a double-spotted 8 × 8 array, and screened
by hybridisation with a number of single-copy and gene-family probes. A 3-dimensional DNA pooling scheme was used to allow
rapid PCR screening of the library based on primer pairs from simple sequence repeat (SSR) and expressed sequence tag (EST)
markers. Positive clones were obtained in all hybridisation and PCR screens carried out so far. Six BAC clones, which hybridised
to a portion of the cloned Rp1-D rust resistance gene, were further characterised and found to form contigs covering most of this complex resistance locus.
Received: 30 August 2000 / Accepted: 6 December 2000 相似文献
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A novel library‐independent approach based on high‐throughput cultivation in Bioscreen and fingerprinting by FTIR spectroscopy for microbial source tracking in food industry 下载免费PDF全文
9.
J. M. SORIANO S. PECCHIOLI C. ROMERO S. VILANOVA G. LLCER E. GIORDANI M. L. BADENES 《Molecular ecology resources》2006,6(2):368-370
The oriental persimmon (Diospyros kaki Lf) is believed to have originated in China with subsequent introduction into Japan and Korea in ancient times. The species was then brought to Europe, Brazil and the USA from Japan in the 19th century. Recent studies highlighted the poor state of identification of cultivars in these countries due to incorrect labelling and presence of synonyms among local varieties. Thus, molecular marker characterization of germplasm resources is of great value for genetic resource preservation and plant breeding of persimmon. Therefore, to identify accessions for further plant breeding and germplasm management, 37 microsatellite loci were developed from a CT/AG‐enriched persimmon genomic library. 相似文献
10.
Nine pairs of polymerase chain reaction (PCR) primers that amplify polymorphic microsatellite loci in the desert locust, Schistocerca gregaria (Forskal), were developed using a magnetic bead‐based enrichment protocol. A sample of 48 locusts collected during the 1993 and 1995 upsurge periods in Eritrea, East Africa, were genotyped. The number of alleles per locus ranged from six to 20; the average was 12.67. Allelic distributions were significantly different between samples from different localities. 相似文献