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991.
Comparative physical mapping of the 5S and 18S-25S rDNA in nine wild Hordeum species and cytotypes 总被引:8,自引:0,他引:8
S. Taketa G. E. Harrison J. S. Heslop-Harrison 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(1):1-9
Absract The physical locations of the 5S and 18S-25S rDNA sequences were examined in nine wild Hordeum species and cytotypes by double-target in situ hybridization using digoxigenin-labelled 5S rDNA and biotin-labelled 18S-25S
rDNA as probes. H. vulgare ssp. spontaneum (2n=2x=14; I-genome) had a similar composition of 5S and 18S-25S rDNA to cultivated barley (H. vulgare ssp. vulgare, I-genome), with two major 18S-25S rDNA sites and minor sites on four of the other five chromosomes; three chromosomes had
5S rDNA sites. The closely related H. bulbosum (2x; also I-genome) showed only one pair of 5S rDNA sites and one pair of 18S-25S rDNA sites on different chromosomes. Four wild
diploid species, H. marinum (X-genome), H. glaucum and H. murinum (Y-genomes) and H. chilense (H-genome), differed in the number (2–3 pairs), location, and relative order of 5S and the one or two major 18S-25S rDNA
sites, but no minor 18S-25S rDNA sites were observed. H. murinum 4x had three chromosome pairs carrying 5S rDNA, while the diploid had only a single pair. Two other tetraploid species, H. brachyantherum 4x and H. brevisubulatum 4x (both considered to have H-type genomes), had minor 18S-25S rDNA sites, as well as the major sites. Unusual double 5S rDNA
sites – two sites on one chromosome arm separated by a short distance – were found in the American H-genome species, H. chilense and H. brachyantherum 4x. The results indicate that the species H. brachyantherum 4x and H. brevisubulatum 4x have a complex evolutionary history, probably involving the multiplication of minor rDNA sites (as in H. vulgare sensu lato), or the incorporation of both I and H types of genome. The rDNA markers are useful for an investigation of chromosome evolution
and phylogeny.
Received: 9 February 1998 / Accepted: 14 July 1998 相似文献
992.
C.-L. Ky J. Louarn B. Guyot A. Charrier S. Hamon M. Noirot 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):628-637
Chlorogenic acids (CGA) are phenolic compounds commonly found in green coffee beans. The main CGA classes are caffeoylquinic
acids (CQA), dicaffeoylquinic acids (diCQA), and feruloylquinic acids (FQA). Each contains three isomers differing in the
number and identity of the acylating residues. An interspecific cross between Coffea pseudozanguebariae (low CGA content) and C. liberica var ‘dewevrei’ (high CGA content) was investigated for CGA contents in F1 and back-cross hybrids. Relations within and between CGA classes were studied and confirmed the known biosynthesis pathway.
A single major gene was noted for the 3-FQA isomer; absence was dominant. Additivity was found for most other isomers either
with or without the transformation of variables. Conversely, most ratios were not additive, due to a curvilinear relation
between some isomers. The consequences for breeding both in terms of cup taste improvement and disease resistance are discussed.
Received: 20 July 1998 / Accepted: 14 August 1998 相似文献
993.
X. Shan T. K. Blake L. E. Talbert 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):1072-1078
Conversion of amplified fragment length polymorphisms (AFLPs) to sequence-specific PCR primers would be useful for many genetic-linkage
applications. We examined 21 wheat nullitetrasomic stocks and five wheat-barley addition lines using 12 and 14 AFLP primer
combinations, respectively. On average, 36.8% of the scored AFLP fragments in the wheat nullitetrasomic stocks and 22.3% in
the wheat-barley addition lines could be mapped to specific chromosomes, providing approximately 461 chromosome-specific AFLP
markers in the wheat nullitetrasomic stocks and 174 in the wheat-barley addition lines. Ten AFLP fragments specific to barley
chromosomes and 16 AFLP fragments specific to wheat 3BS and 4BS chromosome arms were isolated from the polyacrylamide gels,
re-amplified, cloned and sequenced. Primer sets were designed from these sequences. Amplification of wheat and barley genomic
DNA using the barley derived primers revealed that three primer sets amplified DNA from the expected chromosome, five amplified
fragments from all barley chromosomes but not from wheat, one amplified a similar-sized fragment from multiple barley chromosomes
and from wheat, and one gave no amplification. Amplification of wheat genomic DNA using the wheat-derived primer sets revealed
that three primer sets amplified a fragment from the expected chromosome, 11 primer sets amplified a similar-sized fragment
from multiple chromosomes, and two gave no amplification. These experiments indicate that polymorphisms identified by AFLP
are often not transferable to more sequence-specific PCR applications.
Received: 30 June 1998 / Accepted: 26 October 1998 相似文献
994.
XET-related genes and growth kinematics in barley leaves 总被引:2,自引:0,他引:2
DV, displacement velocity
GA
REGR, relative elemental growth rate
XET, xyloglucan-endotransglycosylase
Recently Schünmann et al. (1997 ; Plant, Cell and Environment 20, 1439–1450) investigated the correlation of spatial patterns of xyloglucan-endotransglycosylase (XET) activity, XET-related mRNAs, and growth in elongating barley ( Hordeum vulgare L.) leaves. Here, methodological difficulties in the kinematic growth analysis are discussed, and it is concluded that the role that XET-related gene activity plays in the control of spatial growth patterns remains undetermined. 相似文献
995.
Cowpea trypsin inhibitor (CpTI) gene was transformed into Brassica oleracea var. capitara variety "Yingchun" and "Jingfeng" mediated by the Agrobacterium tumefaciens LBA4404(pRCL27). Transgenic plants were obtained from transformed calli or explants. It was shown from the ELISA assay that NPT Ⅱgene was expressed in the transgenic cabbage cells. The integration of the CpTI gene into cabbage genome DNA was confirmed by Southem blotting. Insect-tolerance of the transgenic plants to Pieris rapae L. was observed by bioassays on the transgenic plants in the laboratory. 相似文献
996.
The system of high synchronous frequency of somatic embryogenesis and somatic embryo seedling formation was established by means of embryonic cell hne 1 ( CL1 ) of Camellia sinensis var. assamica Kitamura. Modified MS was used as the basic medium. Cultures of CL1 was transferred to the aqueous induced medium (0.05 mg/L 2,4-D + 0.50 mg/L 6-BA) from the maintenance medium (0.1 mg/L 2,4-D + 0.5 mg/L 6-BA) for somatic embryos induction under dark condition. 28 days later, they were cultured in the liquid differentiation medium. Various kinds of somatic embryos were obtained after another 28 days. The frequency of somatic embryos was 81.5 %. Various mesh sizes of sieves were applied to collect the somatic embryos in different developmental stages which could develop to mature stage in the aqueous growth medium ( 1/2 MS + 1.0 mg/L GA3 + 0.5 mg/L 6-BA). ABA was effective to promote the formation of highly qualified somatic embryo. The mature somatic embryos sized 20 to 70 mesh had the conversion frequency 75 %. The development of somatic embryogenesis studied under a cell suspension culture system was similar to the zygotic embryogenesis. 相似文献
997.
中国丛藓科的新变种及新记录种 总被引:1,自引:0,他引:1
本文发表了中国丛藓科一新变种, 侧立藓粗台变种Pleuroweisias chliephackei Limpr. Var apophysis Gao et X. Y. Jia, var. nov. 和一新记录种, 芽胞扭口藓Barbula horrinervisSaito. 相似文献
998.
999.
In the present study, several kinds of phytohormones were used for the control of sex differentiation of the potentially female floral buds of Lagenaria siceraria var. hispida in vitro. It was shown that both GA3 and STS (silver thiosulphate) could effectively change the direction of sex differentiation of the potentially female floral buds in vitro. In the MS medium, supplemented with IAA, BA and ACC(1-aminocyclopropane-l-carboxylic acid) at l nmol/L, male flowers would be induced from the potentially female floral buds by the addition of GA3 (1–500μmol/L). Herein the male flowers were induced more effectively by GA3 within 5–-20 μmol/L but it was not as effective as STS. In the MS medium supplemented with IAA, BA and ACC at 1 nmol/L and with GA3 at 20 nmol/L more male flowers were differentiated from the potentially female floral buds with the addition of STS within 100–500 μmol/L. On the contrary, when the MS medium were supplemented with IAA and ACC at 1 nmol/L and with BA increased to 100 nmol/L more female flowers were differentiated from the potentially female floral buds, even with addition of 10–50 nmol/L of GA3. 相似文献
1000.
Liu Qing-hua aim Li Zheng-li 《植物学报(英文版)》1990,32(12)
This paper deals with the effects of four plant growth substances, ic. IAA, NAA, 2,4-D and GA and their different concentration on rind-regeneration after girdling in Solanum melongen var. esculantum. The formation of callus was promoted by IAA, NAA and GA, but retarded by 2,4-D in early stage. The initiation of vascular cambium in callus was retarded by all these substances. However, an increase in amount of xylem was promoted by IAA at low concentrations. The different concentrations of NAA and GA affected a decrease in amount of xylem. The formation of "bundled" vascular tissue was impelled by NAA, GA and 2,4-D. The initiation of phellogen was promoted by IAA and NAA at high concentrtion. In addition, the nest-like tracheid mass was induced in callus by IAA and NAA frequently. 相似文献