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101.
102.
The influence of elevated CO2 on non-structural carbohydrate distribution and fructan accumulation in wheat canopies 总被引:2,自引:1,他引:2
We grew 2.4 m2 wheat canopies in a large growth chamber under high photosynthetic photon flux (1000 μmol m−2 s−1) and using two CO2 concentrations, 360 and 1200 μmol mol−1. Photosynthetically active radiation (400–700 nm) was attenuated slightly faster through canopies grown in 360μmol mol−1 than through canopies grown in 1200μmol mol−1, even though high-CO2 canopies attained larger leaf area indices. Tissue fractions were sampled from each 5-cm layer of the canopies. Leaf tissue sampled from the tops of canopies grown in 1200μmol mol−1 accumulated significantly more total non-structural carbohydrate, starch, fructan, sucrose, and glucose (p≤ 0.05) than for canopies grown in 360μmol mol−1. Non-structural carbohydrate did not significantly increase in the lower canopy layers of the elevated CO2 treatment. Elevated CO2 induced fructan synthesis in all leaf tissue fractions, but fructan formation was greatest in the uppermost leaf area. A moderate temperature reduction of 10 °C over 5d increased starch, fructan and glucose levels in canopies grown in 1200μmol mol−1, but concentrations of sucrose and fructose decreased slightly or remained unchanged. Those results may correspond with the use of fructosyl-residues and release of glucose when sucrose is consumed in fructan synthesis. 相似文献
103.
The effect of GA3 on coleoptile-and first leaf elongation of tall (rht1) and semi-dwarf (Rht1) nearly-isogenic genotypes, within each of 25 random F9 wheat families, was determined on seedlings grown in a growth room at 18 °C. Conspicuous and very significant inter-family variation in the response of the first leaf to GA3 application was found in both the rht1 and Rht1 genotypes. The magnitudes of the response of the different families within genotypes to GA3 were not related to the leaf length of their untreated seedlings. It is suggested that, under given environmental conditions, background genotypic effects, inducing inter-family variation in responsiveness to GA3, regulate the elongation growth up to the limits set by the Rht alleles. 相似文献
104.
105.
106.
M. R. Perretant T. Cadalen G. Charmet P. Sourdille P. Nicolas C. Boeuf M. H. Tixier G. Branlard S. Bernard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(8):1167-1175
A set of 187 doubled haploid lines derived from the cross between cvs. Courtot and Chinese Spring was explored for QTLs for
three bread-making quality tests: hardness, protein content and strength of the dough (W of alveograph). The scores of the
parental lines were quite different except for protein content, and the population showed a wide range of variation. About
350 molecular and biochemical markers were used to establish the genetic map, and technological criteria were evaluated in
1 to 3 years. QTL detection was performed by the ”marker regression” method. The most significant unlinked markers were used
in the model as covariates, and the results were tested by bootstrap resampling. For hardness, we confirmed a previously tagged
major QTL on chromosome 5DS, and two additional minor QTLs were found on chromosome 1A and 6D, respectively. For protein content
two main QTLs were identified on chromosomes 1B and 6A, respectively. For W, three consistent QTLs were detected: two at the
same location as those for hardness, on chromosomes 1A and 5D; the third one on chromosome 3B. Therefore, it appeared that
except for the Glu-1A locus, storage protein loci were not clearly involved in the genetic control of the criteria studied
in the present work. Despite the reasonable size of the population no QTL with interactive effects could be substantially
established as measured. All computations were carried out using home-made programmes in Splus language, and these are available
upon request.
Received: 16 May 1999 / Accepted: 15 October 1999 相似文献
107.
小麦PAL基因的克隆及赤霉菌诱导下的表达分析 总被引:1,自引:0,他引:1
利用苯丙氨酸解氨酶(PAL,phenylalanine ammonia-lyase)基因保守区域从小麦抗赤霉病材料苏麦3号中克隆获得4个PAL基因,分别命名为Ta PAL1、Ta PAL2、Ta PAL3、Ta PAL4。4个基因的开放阅读框(ORF,open reading frame)长度分别为2142 bp、2016 bp、2118 bp和2139 bp,分别编码714个、672个、706个和713个氨基酸。基因序列比对发现其相似性达到88.35%,所编码的氨基酸相似性为91.92%,氨基酸序列分析表明4个基因都包含HAL-PAL结构域及PAL结构域。通过接种禾谷镰刀菌,利用荧光定量PCR对PAL基因进行表达分析发现,4个PAL基因全部为上调表达,其中Ta PAL2、Ta PAL3和Ta PAL4最为明显。PAL基因的上调表达,说明PAL基因在小麦抵抗赤霉病菌侵染的机制中可能起着重要作用。 相似文献
108.
Neugschwandtner RW Tlustos P Komárek M Száková J Jakoubková L 《International journal of phytoremediation》2012,14(8):754-771
Enhanced phytoextraction using EDTA for the remediation of an agricultural soil contaminated with less mobile risk elements Cd and Pb originating from smelting activities in Príbram (Czech Republic) was assessed on the laboratory and the field scale. EDTA was applied to the first years crop Zea mays. Metal mobilization and metal uptake by the plants in the soil were monitored for two additional years when Triticum aestivum was planted. The application ofEDTA effectively increased water-soluble Cd and Pb concentrations in the soil. These concentrations decreased over time. Anyhow, increased concentrations could be still observed in the third experimental year indicating a low possibility of groundwater pollution after the addition of EDTA during and also after the enhanced phytoextraction process under prevailing climatic conditions. EDTA-applications caused phytotoxicity and thereby decreased biomass production and increased Cd and Pb uptake by the plants. Phytoextraction efficiency and phytoextraction potential were too low for Cd and Pb phytoextraction in the field in a reasonable time frame (as less than one-tenth of a percent of total Cd and Pb could be removed). This strongly indicates that EDTA-enhanced phytoextraction as implemented in this study is not a suitable remediation technique for risk metal contaminated soils. 相似文献
109.
In order to explore the genetics of dark-induced senescence in winter wheat(Triticum aestivum L.),a quantitative trait loci(QTL)analysis was carried out in a doubled haploid population developed from a cross between the varieties Hanxuan 10(HX)and Lumai 14(LM).The senescence parameters chlorophyll content(Chl a+b,Chl a,and Chl b),original fluorescence(Fo),maximum fluorescence level(Fm),maximum photochemical efficiency(Fv/Fm),and ratio of variable fluorescence to original fluorescence(Fv/Fo)were evaluated in the second leaf of whole three-leaf seedlings subjected to 7 d of darkness.A total of 43 QTLs were identified that were associated with dark-induced senescence using composite interval mapping.These QTLs were mapped to 20 loci distributed on 11 chromosomes:1B,1D,2A,2B,3B,3D,5D,6A,6B,7A,and 7B.The phenotypic variation explained by each QTL ranged from 7.5% to 19.4%.Eleven loci coincided with two or more of the analyzed parameters.In addition,14 loci co-located or were linked with previously reported QTLs regulating flag leaf senescence,tolerance to high light stress,and grain protein content(Gpc),separately. 相似文献
110.
Changes in the Activity of Antioxidant Enzymes in Wheat Leaves and Roots as a Function of Nitrogen Source and Supply 总被引:3,自引:0,他引:3
Polesskaya O. G. Kashirina E. I. Alekhina N. D. 《Russian Journal of Plant Physiology》2004,51(5):615-620
The activity of enzymes participating in the systems of antioxidant protection was assayed in the second leaf and roots of 21-day-old wheat seedlings (Triticum aestivum L.) grown in a medium with nitrate (NO–
3 treatment), ammonium (NH+
4 treatment), or without nitrogen added (N-deficiency treatment). The activities of superoxide dismutase (SOD), peroxidase, ascorbate peroxidase, glutathione reductase, and catalase in the leaves and roots of the NH+
4 plants was significantly higher than in the plants grown in the nitrate medium. The activity of SOD decreased and ascorbate peroxidase markedly increased in leaves, whereas the activity of ascorbate peroxidase increased in the roots of N-deficient plants, as compared to the plants grown in nitrate and ammonium. Low-temperature incubation (5°, 12 h) differentially affected the antioxidant activity of the studied plants. Whereas leaf enzyme activities did not change in the NH+
4 plants, the activities of SOD, peroxidase, ascorbate peroxidase, and catalase markedly increased in the NO–
3 plants. In leaves of the N-deficient plant, the activity of SOD decreased; however, the activity of other enzymes increased. In response to temperature decrease, catalase activity increased in the roots of NO–
3 and NH+
4-plants, whereas in the N-deficient plants, the activity of peroxidase increased. Thus, in wheat, both nitrogen form and nitrogen deficiency changed the time-course of antioxidant enzyme activities in response to low temperature. 相似文献