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871.
Biljana Stojković Darka Šešlija Jovanović Jelena Perovanović Nikola Tucić 《Ethology : formerly Zeitschrift fur Tierpsychologie》2011,117(9):812-821
We evaluated the degree of reproductive isolation between laboratory populations of the seed beetle (Acanthoscelides obtectus) selected to reproduce early (E) or late (L) in life, where different levels of sexual activity and sexual discrimination have been detected. We found a significant level of behavioral isolation among populations within the E selection regime in which beetles showed enhanced early‐life fitness traits and low sexual activity. In contrast, substantially higher levels of sexual activity and an indiscriminate mating system inhibited rather than promoted pre‐zygotic isolation between the L populations. Our results indicate that the study of sexual activity levels may be crucial for understanding the first steps in the pre‐zygotic isolation among allopatric populations subjected to uniform selection. 相似文献
872.
Jelena Postic Jasenka Cosic Karolina Vrandecic Drazenka Jurkovic Amgad A. Saleh John F. Leslie 《Journal of Phytopathology》2012,160(2):76-81
Weeds are alternative hosts of plant pathogens and when colonized may not exhibit disease symptoms. In 2008 and 2009, samples of weeds and plant debris were collected from 12 locations in eastern Croatia, and 300 Fusarium isolates colonizing them were identified. Strains were grouped and identified based on morphology and amplified fragment length polymorphism (AFLP) patterns. Portions of the β‐tubulin and translocation elongation factor 1‐α genes were sequenced from representative strains of each group to confirm the identifications. Fourteen Fusarium species were identified with F. graminearum (20%), F. verticillioides (18%), F. oxysporum (16%), F. subglutinans (13%) and F. proliferatum (11%) all present as more than 10% of the population. Fusarium acuminatum, F. avenaceum, F. concolor, F. crookwellense (F. cerealis), F. equiseti, F. semitectum, F. solani, F. sporotrichioides and F. venenatum, were all present at frequencies < 8%. Our results indicate that economically important Fusarium spp. may be isolated from numerous alternative hosts during the off season and that weeds and plant debris can serve as a reservoir of genetically diverse inoculum. 相似文献
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Ljiljana Tubić Goran Anačkov Jelena Milojević Nabil Ghalawenji Nevena Mitić Ružica Igić Snežana Zdravković-Korać 《Plant Cell, Tissue and Organ Culture》2014,118(1):101-110
This study assessed the shoot regeneration capacity of root-tips isolated from single seed-derived individual plants, obtained from a wild, open-pollinated micropopulation of shallot (Allium ascalonicum). Considerable variation was observed in the regeneration capacities of individual lines, ranging from 0.93 to 100 %, and a mean bud number per root explant between 0.09 and 20.67. One line was found to be superior, and was chosen for protocol optimization, focusing on the 2,4-D/BA ratio, duration of the CI phase and light conditions. The application of the optimized protocol to other lines, selected for their variable regeneration capacities, enhanced the process of regeneration and shortened the time required to obtain healthy plantlets, even in inferior lines. However, highly responsive lines remained superior, indicating that differences at the individual level must not be overlooked. The conditions employed in this study may serve as a base to facilitate the application of molecular breeding methods in shallot. 相似文献
875.
Marija V. Dimitrijevic Violeta D. Mitic Jelena S. Nikolic Aleksandra S. Djordjevic Jelena J. Mutic Vesna P. StankovJovanovic Gordana S. Stojanovic 《化学与生物多样性》2019,16(2)
The goal of this research was a comprehensive analysis of four wild edible mushroom species, Cantharellus cinereus, Clavariadelphus pistillaris, Clitocybe nebularis and Hygrocybe punicea, which have not been analyzed so far. Extracts of different polarities have been prepared and evaluated for their antioxidant activities by DPPH, ABTS, FRAP, TRP and CUPRAC methods. For all extracts, total phenolic content was determined. Based on the analysis, it was shown that solvent type had a significant effect on the antioxidant capacities of mushroom extracts, so water extracts showed the highest activity. Furthermore, the analysis includes determination of mineral composition, fatty acid profiles and antimicrobial activity. Unsaturated fatty acids, which are very important for human health, are dominant in the studied mushroom species. Linoleic and oleic acid consist of over 50 % of the total fatty acid composition. Seventeen biologically important and toxic elements have been analyzed by ICP‐OES and ICP‐MS and results showed that the element concentrations were species‐dependent. Also, it has been found that analyzed mushrooms did not show any antimicrobial activity. Chemometric analysis was used to understand the connection between the extracts of different polarities. 相似文献
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Jelena Kosoric Ralph Anthony D. Williams Mark P. Hector Paul Anderson 《International journal of peptide research and therapeutics》2007,13(4):497-503
The salivary protein statherin is an inhibitor of spontaneous and secondary precipitation of hydroxyapatite (HAp). It is also
detected in enamel pellicle. The N-terminal region of statherin is involved in its adsorption onto tooth surfaces, and, calcium
binding. A peptide (StN21) was designed with a 21 amino acid sequence identical to the N-terminus of statherin. The aim was
to measure the effect of StN21 on the rate of mineral loss in a model system for dental caries and erosion using HAp subjected
to artificial carious and erosive conditions. StN21 was synthesised using Fmoc chemistry. A surface of each HAp block was
exposed to solution containing StN21 at concentrations 9.4–376 μmol L−1 (in phosphate buffer) for 24 h. Controls were HAp exposed to buffer only, and HAp exposed to lysozyme. Demineralising solution
(0.1 mol L−1 acetic acid, pH 4.5, 1.0 mmol L−1 calcium and 0.6 mmol L−1 phosphate) was circulated past the HAp blocks at 0.4 mL min-1 to mimic carious and erosive conditions. Scanning microradiography was used to measure the rate of mineral loss for demineralisation
periods of 3 weeks. The rate of mineral loss of the samples exposed to StN21 was reduced by ∼40% compared to the controls,
but no dependence on the concentration of StN21 was observed at the concentrations used. StN21 has been shown to be a potent
and stable peptide that has potential as a preventive/therapeutic agent in the treatment of enamel erosion and dental caries. 相似文献