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861.
J. E. Werner-Fraczek T. J. Close 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):220-226
A collection of 200 wheat (Triticum aestivum L. cv ‘Chinese Spring’) cytogenetic stocks (nullisomic, tetrasomic, nulli-tetrasomic, ditelosomic and deletion lines, addition
and substitution stocks from intra- and inter-specific crosses) was utilized to determine the proteins encoded by some of
the wheat and barley dehydrin genes, using a western blot procedure. Proteins extracted from seeds were reacted with antibodies
that recognize dehydrins in a wide range of plants, including wheat and barley. Proteins encoded by dehydrin loci in chromosome
arms 4DS, 5BL and 6AL of ‘Chinese Spring’ wheat were assigned by this method. There was also evidence of a regulatory factor
on 5B in the vicinity of the dhn genes, and on 5H in wheat-barley addition lines, that is required for a normal level of expression of seed dehydrins in hexaploid
wheat. Further understanding of this putative regulatory factor would be helpful for the interpretation of linkage studies
that may relate dehydrin gene expression to phenotypes such as dehydration, salinity or low-temperature tolerance.
Received: 27 August 1997 / Accepted: 4 February 1998 相似文献
862.
S. Nasuda B. Friebe W. Busch R. G. Kynast B. S. Gill 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(6-7):780-785
The genetic constitutions of chromosome 2M of Aegilops comosa and the derived wheat-Ae. comosa translocations were analyzed by molecular cytogenetic techniques. Hybridization of 15 RFLP markers covering the entire length of the group-2 chromosomes revealed that chromosome 2M was structurally rearranged compared to the homoeologous chromosomes of wheat by either a pericentric inversion or a terminal intrachromosomal translocation. The breakpoint of the rearrangement was located in a region between the loci Xpsr131 and Xcdo405, resulting in the translocation of 47% of 2MS to 2ML. This aberrant structure of 2M allowed homoeologous recombination between 2M and its wheat counterpart only in the translocated segment on 2ML. C-banding and genomic in situ hybridization analyses confirmed that all translocation chromosomes consisted of the complete 2MS arm, a large part of 2ML, and very small distal segments derived from 2AS or 2DS, as expected from the aberrant structure of chromosome 2M. Thus, the translocation in the line 2A-2M?4/2 can be described as T2AS-2M?1L???2M?1S and the translocations in the lines Compair and 2D-2M?3/8 as T2DS-2M?1L???2M?1S. RFLP analysis determined the breakpoints in these translocation chromosomes to be within the telomeric 16% of the wheat chromosome arms. The breakpoint of the 2A/2M translocation was between Xbcd348 and Xcdo783, and that of the 2D/2M translocation was between Xcdo783 and Xpsr666. Because the translocation chromosomes retain the structural aberration found in chromosome 2M, further exploitation of the wheat-Ae. comosa translocations for cultivar improvement is questionable. 相似文献
863.
G. D. Parker K. J. Chalmers A. J. Rathjen P. Langridge 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):238-245
An RFLP map constructed using 150 single seed descent (SSD) lines from a cross between two hexaploid wheat varieties (‘Schomburgk’בYarralinka’)
was used to identify loci controlling flour colour. Flour colour data were obtained from field trials conducted over two seasons
at different sites. The estimated heritability of this trait was calculated as 0.67. Two regions identified in the preliminary
analysis on chromosomes 3A and 7A, accounted for 13% and 60% of the genetic variation respectively. A detailed analysis of
the major locus on 7A was conducted through fine mapping of AFLP markers identified using bulked segregant analysis (BSA).
Seven additional markers were identified by the BSA and mapped to the region of the 7A locus. The applicability of these markers
to identify wheat lines with enhanced flour colour is discussed.
Received: 30 September 1997 / Accepted: 4 February 1998 相似文献
864.
M. H. Tixier P. Sourdille G. Charmet G. Gay C. Jaby T. Cadalen S. Bernard P. Nicolas M. Bernard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(7):1076-1082
An intervarietal molecular-marker map was used for the detection of genomic regions influencing crossability between wheat
(Triticum aestivum L. em Thell) and rye (Secale cereale L.). Analysis of deviance and logistic marker-regression methods were conducted on data from doubled haploid lines from a
cross between “Courtot” and “Chinese Spring”. A major quantitative trait locus (QTL) involved in crossability, associated
with the marker Xfba367-5B, was detected on the short arm of chromosome 5B. An additional locus, Xwg583-5B, was indicated on the long arm of chromosome 5B. This minor QTL might correspond to Kr1 which was presumed to be the major gene controlling crossability. Another locus of the genome, Xtam51-7A on chromosome 7A, was significantly associated with this trait. Alleles of “non-crossability” were contributed by the non-crossable
cultivar “Courtot”. The three-marker model explains 65% of the difference in crossability between the two parents. The present
results are discussed in relation to those previously carried out to locate the Kr genes by using the telocentric mapping technique.
Received: 27 February 1998 / Accepted: 15 May 1998 相似文献
865.
866.
A. J. Worland V. Korzun M. S. Röder M. W. Ganal C. N. Law 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(8):1110-1120
Wheat microsatellite WMS 261 whose 192-bp allele has been shown to be diagnostic for the commercially important dwarfing
gene Rht8 was used to screen over 100 wheat varieties to determine the worldwide spread of Rht8. The results showed Rht8 to be widespread in southern European wheats and to be present in many central European wheats including the Russian varieties
‘Avrora’, ‘Bezostaya’ and ‘Kavkaz’. Rht8 appears to be of importance to South European wheats as alternative giberellic acid (GA)-insensitive dwarfing genes do not
appear to be adapted to this environment. The very successful semi-dwarf varieties bred by CIMMYT, Mexico, for distribution
worldwide have been thought to carry Rht8 combined with GA-insensitive dwarfing genes. Additional height reduction would have been obtained from pleiotropic effects
of the photoperiod-response gene Ppd1 that is essential to the adaptability of varieties bred for growing under short-winter days in tropical and sub-tropical
areas. The microsatellite analysis showed that CIMMYT wheats lack Rht8 and carry a WMS 261 allelic variant of 165 bp that has been associated with promoting height. This presumably has adaptive
significance in partly counteracting the effects of other dwarfing genes and preventing the plants being too short. Most UK,
German and French wheats carry an allelic variant at the WMS 261 locus with 174 bp. This could be selected because of linkage
with the recessive photoperiod-sensitive ppd1 allele that is thought to offer adaptive significance northern European wheats.
Received: 17 October 1997 / Accepted: 12 November 1997 相似文献
867.
Atmospheric teleconnection patterns associated with wheat stripe rust disease in North China 总被引:5,自引:0,他引:5
Previous work has shown that long-term (>40 years) time series of wheat stripe rust disease from North China contain a signal
related to the Southern Oscillation Index (SOI). However, no cause-and-effect relationships or direct links between SOI and
disease have been established. Because mid-latitude teleconnection patterns form important links between global atmospheric
variations and regional weather anomalies, such as the Southern Oscillation, studies of such patterns could result in a better
physical and biological interpretation for the SOI-disease association observed previously. We used cross-spectral analyses
to determine if and on which time scales severity of stripe rust in five regions of North China between 1952 and 1990 was
associated with fluctuations in four Northern Hemisphere teleconnection patterns. These included the Pacific/North American,
the Western Atlantic, the Western Pacific, and the Eurasian patterns. The analysis showed consistent and significant (P≤0.10) coherence relationships between the Western Atlantic (WA) pattern and stripe rust severity at a periodicity of 3.00
years. The phase relationships showed that, at the 3.00-year periodicity, the WA series and the disease series were out of
phase by about half a period in all five regions. This phase difference indicated that peaks in the WA series, which are associated
with below-normal winter temperatures over much of China, coincided with troughs in the disease series (i.e. low disease severity),
presumably because of the negative effect of low winter temperatures on survival of the stripe rust pathogen. The analysis
further showed that the WA series and the SOI series were highly significantly (P≤0.01) coherent at a periodicity of 4.33 years, which could explain the association between SOI and stripe rust severity reported
previously.
Received: 12 February 1997 / Accepted: 18 May 1998 相似文献
868.
“龙麦15”2+12与5+10亚基近等基因系面粉品质差异的研究 总被引:2,自引:0,他引:2
通过对小麦栽培品种龙麦15中的同形小种进行SDS-PAGE和A-PAGE的分析,在国内首次获得了一对Glu-D1位点高分子量麦谷蛋白亚基分别为2+12和5+10的近等基因系。对该近等基因系面粉品质的分析表明,带有5+10亚基的龙麦15比事有2+12亚基的龙麦15的Zeleny沉淀值高12%,沉淀值/湿面筋的比值由1.03提高到1.32。该实验结果证明,5+10亚基对面粉品质贡献确实优于2+12亚基 相似文献
869.
小麦胞质突变型雄性不育系85EA与其保持系线粒体DNA的比较研究 总被引:6,自引:1,他引:6
85EA是通过电子束辐照获得的胞质突变型小麦不育要用RFLP和RAPD技术对85EA及春保持系的线粒体DNA进行了比较研究。RFLP分析表明85EA线粒体基因组中coxⅡ基因的位置结构与保持系发生了变化;RAPD分析中引物OPD-15扩增产物在不育系和保持系间有明显差异,不育系的扩增产物比保持系多1条分子量为0.6kb的特展览 要带,用T-easy vector克隆该不育系特异条带并命名为OPD- 相似文献
870.
Selection and evaluation of the potential of choline-metabolizing microbial strains to reduce Fusarium head blight 总被引:1,自引:0,他引:1
D.A. Schisler N.I. Khan M.J. Boehm P.E. Lipps P.J. Slininger S. Zhang 《Biological Control》2006,39(3):497-506
Choline and betaine are found in wheat flower tissues and have been implicated in stimulating hyphal growth of the primary causal agent of Fusarium head blight (FHB), Gibberella zeae. Choline metabolizing strains (CMS) from wheat anthers may therefore be a useful source of antagonists of G. zeae. One-hundred twenty-three of 738 microbial strains that were recovered from wheat anthers collected from plants grown in Illinois and Ohio were CMS as determined by growth in a liquid medium containing choline as a sole carbon and nitrogen source and a colorimetric, choline oxidase-based assay of culture filtrate. Thirty-one out of 123 CMS reduced FHB disease severity by at least 25% in greenhouse tests on wheat and 17 reduced FHB severity by at least 50%. All five CMS selected for field testing in 2003 reduced disease severity compared to the untreated check at both field locations on moderately resistant cultivar Freedom. Freedom wheat treated with Pseudomonas sp. AS 64.4 had 63% and 46% less FHB severity than untreated wheat at the two sites. Three of five CMS reduced severity at both locations on susceptible cultivar Pioneer Brand 2545. Disease control was comparable to that obtained using the fungicide Folicur 3.6F. Selection of wheat anther colonists for ability to utilize choline as a sole carbon and nitrogen source has utility as a screening tool in the search for efficacious antagonists of G. zeae although choline utilization does not insure that an isolate will be an effective biocontrol agent against Fusarium head blight. 相似文献