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111.
Linkage analysis in tetraploid potato and association of markers with quantitative resistance to late blight ( Phytophthora infestans ) 总被引:5,自引:0,他引:5
R. C. Meyer D. Milbourne C. A. Hackett J. E. Bradshaw J. W. McNichol R. Waugh 《Molecular & general genetics : MGG》1998,259(2):150-160
We have constructed a partial linkage map in tetraploid potato which integrates simplex, duplex and double-simplex AFLP markers.
The map consists of 231 maternal and 106 paternal markers with total map lengths of 990.9 cM and 484.6 cM. The longer of the
two cumulative map lengths represents approximately 25% coverage of the genome. In tetraploids, much of the polymorphism between
parental clones is masked by `dosage' which significantly reduces the number of individual markers that can be scored in a
population. Consequently, the major advantage of using AFLPs – their high multiplex ratio – is reduced to the point where
the use of alternative multi-allelic marker types would be significantly more efficient. The segregation data and map information
have been used in a QTL analysis of late blight resistance, and a multi-allelic locus at the proximal end of chromosome VIII
has been identified which contributes significantly to the expression of resistance. No late blight resistance genes or QTLs
have previously been mapped to this location.
Received: 1 October 1997 / Accepted: 18 March 1998 相似文献
112.
Using the Connectivity Map to discover compounds influencing human osteoblast differentiation
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113.
注意缺损多动障碍关联于DXS7位点 总被引:5,自引:2,他引:3
用单细胞凝胶电泳法检测了稀土化合物氯化钇和氯化镨对人外周血淋巴细胞的DNA损伤效应。结果表明,与对照相比,3种不同浓度的氯化钇和氯化镨均可引起淋巴细胞DNA受损后DNA迁移率的显著升高,受损伤细胞的百分率与对照差异明显,提示氯化钇和氯化镨具有一定的遗传毒性。
Abstract:The effect of DNA damage in human lymphocytes induced by yttrium chloride and praseodymium chloride was detected using SCG assay.The results showed that a highly significant increase in DNA migration in DNA-damaged lymphocytes was induced by three different concentrations of yttrium and praseodymium compared with the control,The percentage of DNA-damaged have genetic toxicity.The relevant points to this study are discussed. 相似文献
114.
Chuanxiao Xie Marilyn Warburton Mingshun Li Xinhai Li Muji Xiao Zhuanfang Hao Qi Zhao Shihuang Zhang 《Molecular breeding : new strategies in plant improvement》2008,21(4):407-418
This study analyzes population structure and linkage disequilibrium (LD) among 187 commonly used Chinese maize inbred lines,
representing the genetic diversity among public, commercial and historically important lines for corn breeding. Seventy SSR
loci, evenly distributed over 10 chromosomes, were assayed for polymorphism. The identified 290 alleles served to estimate
population structure and analyze the genome-wide LD. The population of lines was highly structured, showing 6 subpopulations:
BSSS (American BSSS including Reid), PA (group A germplasm derived from modern U.S. hybrids in China), PB (group B germplasm
derived from modern U.S. hybrid in China), Lan (Lancaster Surecrop), LRC (derivative lines from Lvda Reb Cob, a Chinese landrace)
and SPT (derivative lines from Si-ping-tou, a Chinese landrace). Forty lines, which formerly had an unknown and/or miscellaneous
origin and pedigree record, were assigned to the appropriate group. Relationship estimates based on SSR marker data were quantified
in a Q matrix, and this information will inform breeder’s decisions regarding crosses. Extensive inter- and intra-chromosomal
LD was detected between 70 microsatellite loci for the investigated maize lines (2109 loci pairs in LD with D′ > 0.1 and 93 out of them at P < 0.01).This suggests that rapidly evolving microsatellites may track recent population structure. Interlocus LD decay among
the diverse maize germplasm indicated that association studies in QTLs and/or candidate genes might avoid nonfunctional and
spurious associations since most of the LD blocks were broken between diverse germplasm. The defined population structure
and the LD analysis present the basis for future association mapping.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
115.
A series of cyanide-bridged binuclear complexes, (‘S3’)Ni-CN-M[TptBu] (‘S3’ = bis(2-mercaptophenyl)sulfide, TptBu = hydrotris(3-tert-butylpyrazolyl)borate, M = Fe (2-Fe), Co (2-Co), Ni (2-Ni), Zn (2-Zn)) was prepared by the coupling of K[(‘S3’)Ni(CN)] with [TptBu]MX. The isostructural series of complexes was structurally and spectroscopically characterized. A similar coupling strategy was used to synthesize the anionic copper(I) analogue, Et4N{(‘S3’)Ni-CN-Cu[TptBu]}, 2-Cu.An alternative synthesis was devised for the preparation of the linkage isomers of 2-Zn, i.e. of cyanide-bridged linkage isomers. X-ray diffraction, 13C NMR and IR spectral studies established that isomerization to the more stable Ni-CN-Zn isomer occurs. DFT computational results buttressed the experimental observations indicating that the cyanide-bridged isomer is ca. 5 kcal/mol more stable than its linkage isomer. 相似文献
116.
Sfar S Abid A Mahfoudh W Ouragini H Ouechtati F Abdelhak S Chouchane L 《Molecular biology reports》2009,36(4):661-667
Hereditary multiple exostoses (HME) is an autosomal dominant orthopaedic disorder most frequently caused by mutations in the
EXT1 gene. The aim of the present study is to determine the underlying molecular defect of HME in two multigenerational Tunisian
families with 21 affected members and to examine the degree of intrafamilial variability. Linkage analysis was performed using
three microsatellite markers encompassing the EXT1 locus and mutation screening was carried out by direct sequencing. In family 1, evidence for linkage to EXT1 was obtained on the basis of a maximum LOD score of 4.26 at θ = 0.00 with D8S1694 marker. Sequencing of the EXT1 revealed a heterozygous G > T transversion (c.1019G>T) in exon 2, leading to a missense mutation at the codon 340 (p.Arg340Leu).
In family 2 we identified a novel heterozygous 1 bp deletion in the exon 1 (c.529_531delA) leading to a premature codon stop
and truncated EXT1 protein expression (p.Lys177LysfsX15). This mutation was associated with the evidence of an intrafamilial
clinical variability and considered to be a novel disease-causing mutation in the EXT1 gene. These findings provide additional support for the involvement of EXT1 gene in the HME disease. 相似文献
117.
Nobuhisa Shimba Mai Shinagawa Wataru Hoshino Hideyuki Yamaguchi Naoyuki Yamada Ei-ichiro Suzuki 《Analytical biochemistry》2009,393(1):23-28
α-Glucosidase from Aspergillus niger is an enzyme that catalyzes hydrolysis of α-1,4 linkages and transglucosylation to form α-1,6 linkages. In this study, an analytical method of oligosaccharides by nuclear magnetic resonance (NMR) was used to provide quantitative estimation of the fractions of each sugar unit and was applied to characterize the α-glucosidase reaction. Our data indicated that α-glucosidase reacts with the nonreducing end of oligosaccharides to form an α-1,6 linkage, and then a sugar unit with two α-1,6 linkages is gradually produced. Data from mass spectrometry suggested that the sugar unit with two α-1,6 linkages originates mainly from a 3mer and/or 4mer when oligosaccharides are used as substrates. 相似文献
118.
Cold stability of intrinsically disordered proteins 总被引:1,自引:0,他引:1
Agnes Tantos 《FEBS letters》2009,583(2):465-469
Contrary to globular proteins, intrinsically disordered proteins (IDPs) lack a folded structure and they do not lose solubility at elevated temperatures. Although this should also be true at low temperatures, cold stability of IDPs has not been addressed in any scientific work so far. As direct characterization of cold-denaturation is difficult, we approached the problem through a freezing-induced loss-of-function model of globular-disordered functional protein pairs (m-calpain-calpastatin, tubulin-Map2c, Hsp90-ERD14). Our results affirm that in contrast with globular proteins IDPs are resistant to cold treatment. The theoretical and functional aspects of this observation are discussed. 相似文献
119.
One of the biggest challenges facing evolutionary biologists is to identify and understand loci that explain fitness variation
in natural populations. This review describes how genetic (linkage) mapping with single nucleotide polymorphism (SNP) markers
can lead to great progress in this area. Strategies for SNP discovery and SNP genotyping are described and an overview of
how to model SNP genotype information in mapping studies is presented. Finally, the opportunity afforded by new generation
sequencing and typing technologies to map fitness genes by genome-wide association studies is discussed. 相似文献
120.
The mean time to resolution of gene duplication (Tr) is studied in this paper under the double null recessive (DNR) and haplo-insufficient (HI) models within the same analytical
and simulation framework. We show that when population size is not too small (more precisely Nμ > 0.1), Tr for unlinked duplication is usually larger than that for linked and Tr for unlinked duplication under the HI model might be greatly prolonged, which were consistent with previous observations.
Furthermore, by analytical approach we here indicate the primary underlying mechanism is that the frequency of the original
(or wild-type) chromosomal haplotype of the linked duplication decreases nearly exponential to zero with time while that of
the unlinked decreases quickly to an quasi-equilibrium; and this phenomenon is particularly profound under the HI model, because
the quasi-equilibrium frequency of the original chromosomal haplotype (x0) under the HI model is higher than that under the DNR model. These results suggest that recombination and HI model might
jointly contribute to the marked prolongation of Tr even in a modest population. The prolonged Tr and higher quasi-equilibrium frequency of the original allele at both duplicated loci might have offered more opportunities
for the emergence of novel genes. 相似文献