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81.
82.
G. Sarà M. De Pirro C. Romano P. Rumolo M. Sprovieri A. Mazzola 《Helgoland Marine Research》2007,61(4):297-302
Stable isotopes were used to examine the origin of organic matter in Icelandic Ascophyllum-based habitats, the role of different organic matters in filling intertidal food webs and the food preferences of the most
abundant suspension feeders, grazers and predators. We selected three intertidal sites on the SW coast of Iceland where we
sampled in early September 2004, organic matter sources (POM, SOM and most abundant primary producers, A. nodosum and F. vesciculosus) and the most abundant macrofauna species (barnacles, mussels, gastropods, sponge and crabs). Even though the primary production
(Ascophyllum-based) was the same at the three study sites, the isotopic composition of common-among-sites organisms varied due to local
differences in the origin of available POM and SOM and in food web structures. 相似文献
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84.
Vincent M 《BioEssays : news and reviews in molecular, cellular and developmental biology》2012,34(1):72-82
Cancer viewed as a programmed, evolutionarily conserved life-form, rather than just a random series of disease-causing mutations, answers the rarely asked question of what the cancer cell is for, provides meaning for its otherwise mysterious suite of attributes, and encourages a different type of thinking about treatment. The broad but consistent spectrum of traits, well-recognized in all aggressive cancers, group naturally into three categories: taxonomy ("phylogenation"), atavism ("re-primitivization") and robustness ("adaptive resilience"). The parsimonious explanation is not convergent evolution, but the release of an highly conserved survival program, honed by the exigencies of the Pre-Cambrian, to which the cancer cell seems better adapted; and which is recreated within, and at great cost to, its host. Central to this program is the Warburg Effect, whose malign influence permeates well beyond aerobic glycolysis to include biomass interconversion and genomic heuristics. Warburg-type metabolism and genomic instability are targets whose therapeutic disablement is a major priority. 相似文献
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86.
Natsuko Miura Wataru Aoki Naoki Tokumoto Kouichi Kuroda Mitsuyoshi Ueda 《Applied microbiology and biotechnology》2009,85(2):293-301
We developed a novel method to coat living non-genetically modified (GM) cells with functional recombinant proteins. First,
we prepared GM yeast to secrete constructed proteins that have two domains: a functional domain and a binding domain that
recognizes other cells. Second, we cocultivated GM and non-GM yeasts that share and coutilize the medium containing recombinant
proteins produced by GM yeasts using a filter-membrane-separated cultivation reactor. We confirmed that GM yeast secreted
enhanced green fluorescent protein (EGFP) fusion proteins to culture medium. After cocultivation, EGFP fusion proteins produced
by GM yeast were targeted to non-GM yeast (Saccharomyces cerevisiae BY4741ΔCYC8 strain) cell surface. Yeast cell-surface engineering is a useful method that enables the coating of GM yeast cell surface
with recombinant proteins to produce highly stable and accumulated protein particles. The results of this study suggest that
development of cell-surface engineering from GM organisms (GMOs) to living non-GMOs by our novel cocultivation method is possible. 相似文献
87.
Keyne Monro Alistair G. B. Poore 《Evolution; international journal of organic evolution》2009,63(12):3147-3157
Although modular construction is considered the key to adaptive growth or growth‐form plasticity in sessile taxa (e.g., plants, seaweeds and colonial invertebrates), the serial expression of genes in morphogenesis may compromise its evolutionary potential if growth forms emerge as integrated wholes from module iteration. To explore the evolvability of growth form in the red seaweed, Asparagopsis armata, we estimated genetic variances, covariances, and cross‐environment correlations for principal components of growth‐form variation in contrasting light environments. We compared variance–covariance matrices across environments to test environmental effects on heritable variation and examined the potential for evolutionary change in the direction of plastic responses to light. Our results suggest that growth form in Asparagopsis may constitute only a single genetic entity whose plasticity affords only limited evolutionary potential. We argue that morphological integration arising from modular construction may constrain the evolvability of growth form in Asparagopsis, emphasizing the critical distinction between genetic and morphological modularity in this and other modular taxa. 相似文献
88.
89.
Via expression of Cry-proteins, toxic for specific insect groups, genetically modified Bacillus thuringiensis (Bt) maize offers an effective protection against insect pests. In a laboratory experiment with two transgenic and two non-transgenic maize varieties, a potential impact of Bt-maize was examined for the non-target slug Arion vulgaris. Lifetime after field collection, weight change and oviposition was examined for slugs fed with Bt-maize, non Bt-maize or dandelion (Taraxacum officinale). Test parameters were neither significantly different between transgenic and non-transgenic varieties nor among the maize varieties overall. Slugs fed with dandelion showed a significantly longer lifetime after field collection, gained significantly more weight and laid eggs. The results did not show a Bt-effect but indicated the general poor quality of maize as food resource for slugs. 相似文献
90.
Isolation,identification and characterization of soil microbes which degrade phenolic allelochemicals 总被引:1,自引:0,他引:1
Aims: To isolate and characterize microbes in the soils containing high contents of phenolics and to dissolve the allelopathic inhibition of plants through microbial degradation. Methods and Results: Four microbes were isolated from plant soils using a screening medium containing p‐coumaric acid as sole carbon source. The isolates were identified by biochemical analysis and sequences of their 16S or 18S rDNA, and designated as Pseudomonas putida 4CD1 from rice (Oryza sativa) soil, Ps. putida 4CD3 from pine (Pinus massoniana) soil, Pseudomonas nitroreducens 4CD2 and Rhodotorula glutinis 4CD4 from bamboo (Bambusa chungii) soil. All isolates degraded 1 g l?1 of p‐coumaric acid by 70–93% in inorganic and by 99% in Luria‐Bertani solutions within 48 h. They also effectively degraded ferulic acid, p‐hydroxybenzoic acid and p‐hydroxybenzaldehyde. The microbes can degrade p‐coumaric acid and reverse its inhibition on seed germination and seedling growth in culture solutions and soils. Low pHs inhibited the growth and phenolic degradation of the three bacteria. High temperature inhibited the R. glutinis. Co2+ completely inhibited the three bacteria, but not the R. glutinis. Cu2+, Al3+, Zn2+, Fe3+, Mn2+, Mg2+ and Ca2+ had varying degrees of inhibition for each of the bacteria. Conclusions: Phenolics in plant culture solutions and soils can be decomposed through application of soil microbes in laboratory or controlled conditions. However, modification of growth conditions is more important for acidic and ions‐contaminated media. Significance and Impact of the Study: The four microbes were first isolated and characterized from the soils of bamboo, rice or pine. This study provides some evidence and methods for microbial control of phenolic allelochemicals. 相似文献