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排序方式: 共有879条查询结果,搜索用时 15 毫秒
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Ewa Dubas Jana Moravčíková Jana Libantová Ildikó Matušíková Eva Benková Iwona Żur Monika Krzewska 《Protoplasma》2014,251(5):1077-1087
Plant embryogenesis is regulated by differential distribution of the plant hormone auxin. However, the cells establishing these gradients during microspore embryogenesis remain to be identified. For the first time, we describe, using the DR5 or DR5rev reporter gene systems, the GFP- and GUS-based auxin biosensors to monitor auxin during Brassica napus androgenesis at cellular resolution in the initial stages. Our study provides evidence that the distribution of auxin changes during embryo development and depends on the temperature-inducible in vitro culture conditions. For this, microspores (mcs) were induced to embryogenesis by heat treatment and then subjected to genetic modification via Agrobacterium tumefaciens. The duration of high temperature treatment had a significant influence on auxin distribution in isolated and in vitro-cultured microspores and on microspore-derived embryo development. In the “mild” heat-treated (1 day at 32 °C) mcs, auxin localized in a polar way already at the uni-nucleate microspore, which was critical for the initiation of embryos with suspensor-like structure. Assuming a mean mcs radius of 20 μm, endogenous auxin content in a single cell corresponded to concentration of 1.01 μM. In mcs subjected to a prolonged heat (5 days at 32 °C), although auxin concentration increased dozen times, auxin polarization was set up at a few-celled pro-embryos without suspensor. Those embryos were enclosed in the outer wall called the exine. The exine rupture was accompanied by the auxin gradient polarization. Relative quantitative estimation of auxin, using time-lapse imaging, revealed that primordia possess up to 1.3-fold higher amounts than those found in the root apices of transgenic MDEs in the presence of exogenous auxin. Our results show, for the first time, which concentration of endogenous auxin coincides with the first cell division and how the high temperature interplays with auxin, by what affects delay early establishing microspore polarity. Moreover, we present how the local auxin accumulation demonstrates the apical–basal axis formation of the androgenic embryo and directs the axiality of the adult haploid plant. 相似文献
875.
The application of high-density genetic maps of rye for the detection of QTLs controlling morphological traits 总被引:1,自引:0,他引:1
Beata Myśków Monika Hanek Aneta Banek-Tabor Robert Maciorowski Stefan Stojałowski 《Journal of applied genetics》2014,55(1):15-26
The development of genetic maps is, nowadays, one of the most intensive research activities of plant geneticists. One of the major goals of genome mapping is the localisation of quantitative trait loci (QTLs). This study was aimed at the identification of QTLs controlling morphological traits of rye and comparison of their localisation on genetic maps constructed with the use of genetically different germplasms. For QTL analyses, two high-density consensus maps of two populations (RIL-S and RIL-M) of recombinant inbred lines (RIL) were applied. Plant height (Ph), length of spikes (Sl) and the number of spikelets per spike (Sps) were studied in both populations. Additionally, the number of kernels per spike under isolation (Kps), the weight of kernels per spike (Kw) and thousand kernel weight (Tkw) were assessed in the RIL-M population. Except for Tkw, the majority of the traits were correlated to each other. The non-parametric Kruskal–Wallis (K-W) test and composite interval mapping (CIM) revealed 18/48 and 24/18 regions of rye chromosomes engaged in the determination of Ph, Sl and Sps in the RIL-S and RIL-M populations, respectively. An additional 18/15 QTLs controlling Kps, Kw and Tkw were detected on a map of the RIL-M population. A numerous group of QTLs detected via CIM remained in agreement with the genomic regions found when the K-W test was applied. Frequently, the intervals indicated by CIM were narrower. 相似文献
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877.
Ludmi̵a Żylińska Ewa Gromadzińska Lilla Lachowicz 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》1999,1437(2):257-264
Recent experimental evidence indicates that some steroid hormones, apart from their well-documented genomic actions, could produce non-genomic rapid effects, and are potent modulators of the plasma membrane proteins, including voltage- and ligand-operated ion channels or G protein-coupled receptors. Neuroactive steroids, 17β-estradiol, testosterone, pregnenolone sulfate and dehydroepiandrosterone sulfate, after a short-time incubation directly modulated the activity of plasma membrane Ca2+-ATPase purified from synaptosomal membranes of rat cortex. The sulfate derivatives of dehydroepiandrosterone and pregnenolone applied at concentrations of 10?11–10?6 M, showed an inverted U-shape potency in the regulation of Ca2+-ATPase activity. At physiologically relevant concentrations (10?8–10?9 M) a maximal enhancement of the basal activity reached 200%. Testosterone (10?11–10?6 M) and 17β-estradiol (10?12–10?9 M) caused a dose-dependent increase in the hydrolytic ability of Ca2+-ATPase, and the activity with the highest concentration of steroids reached 470% and 200%, respectively. All examined steroids decreased the stimulatory effect of a naturally existing activator of the calcium pump, calmodulin. The present study strongly suggests that the plasma membrane calcium pump could be one of the possible membrane targets for a non-genomic neuroactive steroid action. 相似文献
878.
Aneta Hromada-Judycka Hanna Bolibok-Brągoszewska Monika Rakoczy-Trojanowska 《Plant Cell, Tissue and Organ Culture》2010,100(2):131-138
Winter rye (Secale cereale L.) is known to be recalcitrant to tissue culture response (TCR). Moreover, the mechanisms controlling TCR are poorly recognized.
In the present study, a Genetically Directed Differential Subtraction Chain (GDDSC) strategy was used to isolate genomic regions
associated with TCR. Two pairs of bulks, R-NR and E > 90–E < 25, were prepared, and for each pair, the bulk was used both
as a tester and as a driver. After eight rounds of subtraction, 45 unique GDDSC products were obtained. To verify the connection
between GDDSCs and TCR two approaches were applied: Real-Time RT-PCR analysis and genetic mapping. The expression profiles
of four out of six investigated products agrees with the phenotype and subtraction direction. Two from the developed GDDSC-SCAR
markers showed polymorphism in lines L9 and L318, the parental components of a mapping population. The polymorphic SCAR GDDSC
markers were mapped on the rye chromosome 4R (SCAR-GDDSC NR 440BamHI) and 6R (SCAR-GDDSC E < 25 340BamHI). The marker E < 25_340B9 was localized in the border region of QTL for embryogenic callus production. 相似文献
879.
Sebastian Gnat Dominik Łagowski Mariusz Dyląg Jessica Zielinski Aneta Nowakiewicz 《Journal of biophotonics》2021,14(10):e202100150
The intense search for the “Holy Grail” of antifungal therapy can be observed today. The searches are not limited only to discovery of potential antifungal drugs, but also new therapeutic strategies involving the use of chemosensitizers to achieve synergistic effect or physicochemical factors inducing stress conditions in fungal cells. In this study was examined in vitro effectiveness of photodynamic antifungal strategy with methylene blue using a light beam with a wavelength equal to 635 nm toward the Trichophyton verrucosum susceptible and itraconazole- and/or fluconazole-resistant strains. Methylene blue used at concentration equal to 5 μg/mL and in the presence of 40 J/cm2 of light energy showed fungicidal effect toward the susceptible strains. However, for azole-resistant isolates, only the energy dose equal to 60 J/cm2 at 5 μg/mL of methylene blue allowed to kill the pathogen. This study confirms that methylene blue induced by red light has a definite inhibitory effect on zoophilic dermatophytes. 相似文献