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991.
The flagfish (Jordanella floridae) is commonly used in studies of wetlands ecology. Here we describe the isolation of ten microsatellite loci, six of which
were polymorphic. The observed number of alleles ranged from 4 to 24 and observed heterozygosities ranged from 0.59 to 0.81
for the polymorphic loci. The isolation of these markers will enable estimations of genetic diversity in natural populations. 相似文献
992.
Isolation and characterization of microsatellite markers for the endangered <Emphasis Type="Italic">Taxus yunnanensis</Emphasis> 总被引:1,自引:0,他引:1
Ying-Chun Miao Jian-Rong Su Zhi-Jun Zhang Hui Li Jing Luo Ya-Ping Zhang 《Conservation Genetics》2008,9(6):1683-1685
Eleven polymorphic microsatellite loci were characterized for the endangered conifer Taxus yunnanensis. Eight loci were isolated through SSR-anchored PCR, one locus was developed by cross-species amplification tests, while the
last two loci were obtained from cross-species microsatellite sequences available in GenBank. Variability of these markers
was tested in 48 individuals collected from its main distribution range in Southwest China. The number of alleles per locus
ranged from 2 to 9, and the observed and expected heterozygosity varied from 0.000 to 0.625 and from 0.062 to 0.853, respectively.
Ten of these eleven loci were significantly deviated from Hardy–Weinberg expectation, except TS07 which showed a distinct
heterozygote excess. The availability of these new polymorphic microsatellite markers will provide an ideal marker system
for detailed population genetics studies in T. yunnanensis and potentially also for closely related species. 相似文献
993.
Lycopodium fordii Bak. (Lycopodiaceae, Pteridophyta) is a gardening plant with a native, fragmentary distribution in Taiwan. In this study,
we described the development of eleven microsatellite loci in L. fordii for genetic studies. These new markers were tested in 16 individuals of three populations. The number of alleles ranged from
1 to 5 and the expected heterozygosity from 0.41746 to 0.72222. Four of the nine polymorphic loci were significantly deviated
from Hardy-Weinberg expectations due to the heterozygote deficiency. The microsatellite markers have also been proved as informative
genetic markers for other 15 Lycopodium species. 相似文献
994.
F. Fernández-Fernández K. M. Evans J. B. Clarke C. L. Govan C. M. James S. Marić K. R. Tobutt 《Tree Genetics & Genomes》2008,4(3):587-479
Simple sequence repeat (SSR) markers developed from Malus, as well as Prunus, Pyrus and Sorbus, and some other sequence-tagged site (STS) loci were analysed in an interspecific F1 apple progeny from the cross ‘Fiesta’ × ‘Totem’ that segregated for several agronomic characters. A linkage map was constructed
using 259 STS loci (247 SSRs, four SCARs and eight known-function genes) and five genes for agronomic traits—scab resistance
(Vf), mildew resistance (Pl-2), columnar growth habit (Co), red tissues (Rt) and green flesh background colour (Gfc). Ninety SSR loci and three genes (ETR1, Rt and Gfc) were mapped for the first time in apple. The transferability of markers from other Maloideae to Malus was found to be around 44%. The loci are spread across 17 linkage groups, corresponding to the basic chromosome number of
Malus and cover 1,208 cM, approximately 85% of the estimated length of the apple genome. Interestingly, we have extended the top
of LG15 with eight markers covering 25 cM. The average map density is 4.7 cM per marker; however, marker density varies greatly
between linkage groups, from 2.5 in LG14 to 8.9 in LG7, with some areas of the genome still in need of further STS markers
for saturation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
995.
采用微卫星标记研究天然封闭型水体肖四海内鳜放流群体与野生群体的遗传差异,试图从分子水平探讨人工增殖放流群体与野生群体遗传结构的差异。结果表明:鳜两个群体在10对微卫星座位共发现有50个等位基因。其中,放流群体发现有22个等位基因,野生群体发现37个等位基因;通过He和PIC统计发现,野生群体遗传多样性明显高于放流增殖鳜,野生鳜群体表现出更丰富的遗传多样性;由杂合度检验可以看出,两个群体都呈现杂合过剩现象,经哈代-温伯格平衡检验,显示两个群体均显著偏离哈代-温伯格平衡(P0.001),属于连锁不平衡群体;群体间的FST检验,可以看出群体间的FST高于0.25,反映遗传变异主要存在于群体间,而不是群体内部,这充分反映近交及瓶颈效应会引起养殖群体遗传结构的改变,从而导致群体间的遗传分化。
相似文献
996.
尼西鸡遗传多样性微卫星标记分析 总被引:13,自引:0,他引:13
尼西鸡抗病力强,产蛋性能高,适应高海拔及寒冷的气候条件,是具有独特群体遗传特性的高原地方鸡种。为了对其有效保护和合理利用提供遗传背景资料,筛选了家鸡基因组24条染色体上的33个微卫星标记,对随机选取的50个尼西鸡个体进行多态性检测,共检测到122个等位基因,每个座位平均等位基因数为3·7个。该群体平均多态信息含量和平均杂合度分别为0·5514和0·6350,大染色体较小染色体的微卫星多态性程度高。表明尼西鸡属多态性较丰富的群体。 相似文献
997.
J. H. Peng T. Fahima M. S. Röder Y. C. Li A. Dahan A. Grama Y. I. Ronin A. B. Korol E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):862-872
Stripe rust caused by Puccinia striifomis West. is one of the most devastating diseases relating to wheat production. Wild emmer wheat, Triticum dicoccoides, the tetraploid progenitor of cultivated wheat, has proven to be a valuable source of novel stripe-rust resistance genes
for wheat breeding. For example, T. dicoccoides accessions from Mt. Hermon, Israel, are uniformly and highly resistant to stripe-rust. The main objective of the present
study is to map a stripe-rust resistance gene, derived from the unique Mt. Hermon population of wild emmer, using microsatellite
markers. An F2 mapping population was established by crossing stripe-rust resistant T. dicoccoides accession H52 from Mt. Hermon with the Triticum durum cultivar Langdon. The stripe-rust resistance derived from accession H52 was found to be controlled by a single dominant gene
which was temporarily designated as YrH52. Out of 120 microsatellite markers tested, 109 (91%) showed polymorphism between the parental lines. Among 79 segregating
microsatellite loci generated from 56 microsatellite primer pairs, nine were linked to YrH52 with recombination frequencies of 0.02–0.35, and LOD scores of 3.56–54.22. A genetic map of chromosome 1B, consisting of
ten microsatellite loci and the stripe-rust resistance gene YrH52, was constructed with a total map length of 101.5 cM. YrH52 is also closely linked to RFLP marker Nor1 with a map distance of 1.4 cM and a LOD value of 29.62. Apparent negative crossover interference was observed in chromosome
1B, especially in the region spanning the centromere. Negative crossover interference may be a common characteristic of gene-rich
regions or gene clusters in specific chromosomes.
Received: 30 October 1998 / Accepted: 2 November 1998 相似文献
998.
J. K. Roy M. Prasad R. K. Varshney H. S. Balyan T. K. Blake H. S. Dhaliwal H-Singh K. J. Edwards P. K. Gupta 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):336-340
In bread wheat, the transfer of tolerance to preharvest sprouting (PHS) that is associated with genotypes having red kernel
colour to genotypes with amber kernels is difficult using conventional methods of plant breeding. The study here was undertaken
to identify DNA markers linked with tolerance to PHS as these would allow indirect marker-assisted selection of PHS-tolerant
genotypes with amber kernels. For this purpose, a set of 100 recombinant inbred lines (RILs) was developed using a cross between
a PHS-tolerant genotype, SPR8198, with red kernels and a PHS-susceptible cultivar, ‘HD2329’, with white kernels. The two parents
were analysed with 232 STMS (sequence-tagged microsatellite site) and 138 STS (sequence-tagged site) primer pairs. A total
of 300 (167 STMSs and 133 STSs) primer pairs proved functional by giving scorable PCR products. Of these, 57 (34%) STMS and
30 (23%) STS primer pairs detected reproducible polymorphism between the parent genotypes. Using these primer pairs, we carried
out bulked segregant analysis on two bulked DNAs, one obtained by pooling DNA from 5 PHS-tolerant RILs and the other similarly
derived by pooling DNA from 5 PHS-susceptible RILs. Two molecular markers, 1 STMS primer pair for the locus wmc104 anda STS primer pair for the locus MST101, showed apparent linkage with tolerance to PHS. This was confirmed following selective genotyping of individual RILs included
in the bulks. Chi-square contingency tests for independence were conducted on the cosegregation data collected on 100 RILs
involving each of the two molecular markers (wmc104 and MST101) and PHS. The tests revealed a strong association between each of the markers and tolerance to PHS. Using nullisomic-tetrasomic
lines, we were able to assign wmc104 and MST101 to chromosomes 6B and 7D, respectively. The results also indicated that the tolerance to PHS in SPR8198 is perhaps governed
by two genes (linked with two molecular markers) exhibiting complementary interaction.
Received: 15 October 1998 / Accepted: 19 December 1998 相似文献
999.
M. I. Buteler R. L. Jarret D. R. LaBonte 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):123-132
The objectives of the present study were to evaluate the inheritance and nucleotide sequence profiles of microsatellite genetic
markers in hexaploid sweetpotato [Ipomoea batatas (L.) Lam.] and its putative tetraploid and diploid ancestors, and to test possible microsatellite mutation mechanisms in
polyploids by direct sequencing of alleles. Sixty three microsatellite loci were isolated from genomic libraries of I. batatas and sequenced. PCR primers were designed and used to characterize microsatellite loci in two hexaploid I. batatas populations, a tetraploid Ipomoea trifida population, and a diploid I. trifida population. Nine out of the sixty three primer pairs tested yielded a clearly discernible, heritable banding pattern; five
showed Mendelian segregation. All other primer pairs produced either smeared banding patterns, which could not be scored,
or no bands at all in I. batatas. All of the primers which produced discernible banding patterns from I. batatas also amplified products of similar size in tetraploid and diploid I. trifida accessions. The sequence analysis of several alleles in the three species showed differences due to mutations in the repeat
regions consistent with small differences in the repeat number. However, in some cases insertions/deletions and base substitutions
in the microsatellite flanking regions were responsible for polymorphisms in both polyploid and diploid species. These results
provide strong empirical evidence that complex genetic mechanisms are responsible for SSR allelic variation in Ipomoea. Four I. batatas microsatellite loci showed polysomic segregation fitting tetraploid segregation ratios. To our knowledge this is the first
report of segregation ratios for microsatellites markers in polyploids.
Received: 4 January 1999 / Accepted: 4 January 1999 相似文献
1000.
K. Tanaka Y. Tsumura T. Nakamura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):11-15
We have developed microsatellite markers (SSRs) applicable to Fagus crenata using the RAHM method and investigated their polymorphisms. We also applied the SSRs in an analysis of a closely related
species, F. japonica. Here we describe the isolation and characterization of nine polymorphic microsatellite markers, of which eight are applicable
to both species. Among 30 individuals of each of F. crenata and F. japonica we detected a total of 79 and 77 alleles, respectively, with an average of 9.9 and 8.6 alleles per locus. The mean expected
heterozygosity (He) was 0.615 (range: 0.216–0.925) in F. crenata and 0.660 in F. japonica (range: 0.259–0.827). The He values were considerably higher than those previously found for isozymes. Paternity exclusion probabilities for multiple
loci, calculated over all loci, were extremely high (0.999 and 0.998 in F. crenata and F. japonica, respectively): sufficiently high to study pollen flow in both species.
Received: 5 December 1998 / Accepted: 28 December 1998 相似文献