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121.
Gaia Bigiotti Roberta Pastorelli Antonio Belcari Patrizia Sacchetti 《Journal of Applied Entomology》2019,143(4):357-364
The relationship between Bactrocera oleae (Rossi 1790) and its endosymbiont Candidatus Erwinia dacicola is important to achieving effective control of the olive fly population in the field. This bacterium plays a crucial role in the life of B. oleae and is necessary for its fitness. Thus, in the absence of the endosymbiont, B. oleae wild populations in the field might decrease considerably. Copper is one of the most used antimicrobials for horticultural crops worldwide, and its efficacy against Ca. E. dacicola has been demonstrated in field trials. Propolis is another natural antimicrobial compound largely used for its activity in several fields. If propolis and copper prove to be efficient against wild populations of the endosymbiont B. oleae in the field, such a biological restraint might improve sustainable agriculture. We evaluated, under laboratory conditions, the effect of two different copper products (at two different concentrations, 5% and 20%) and propolis on the content of Ca. E. dacicola in the eggs and in the adult oesophageal bulbs of B. oleae. Bulbs were extracted twice, after 2 and 5 weeks of exposure. Real‐time PCR on the bulbs showed a reduction in Ca. E. dacicola content in flies treated with copper (at both 5% and 20%), and from the first to the second extraction, while flies treated with propolis showed an increment of the relative abundance of Ca. E. dacicola. Both copper products (5% and 20%) reduced the egg production after 2 and 5 weeks in comparison with the control and propolis treatments. Moreover, adult mortality was significantly higher with propolis compared with the other treatments. Thus, our results encourage further research in order to develop new tools for the control of the olive fly in the framework of an integrated pest management strategy. 相似文献
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Magazù S Migliardo F Benedetto A La Torre R Hennet L 《European biophysics journal : EBJ》2012,41(4):361-367
In this contribution the effects of the homologous disaccharides trehalose and sucrose on both water and hydrated lysozyme
dynamics are considered by determining the mean square displacement (MSD) from elastic incoherent neutron scattering (EINS)
experiments. The self-distribution function (SDF) procedure is applied to the data collected, by use of IN13 and IN10 spectrometers
(Institute Laue Langevin, France), on trehalose and sucrose aqueous mixtures (at a concentration corresponding to 19 water
molecules per disaccharide molecule), and on dry and hydrated (H2O and D2O) lysozyme also in the presence of the disaccharides. As a result, above the glass transition temperature of water, the MSD
of the water–trehalose system is lower than that of the water–sucrose system. This result suggests that the hydrogen-bond
network of the water–trehalose system is stronger than that of the water–sucrose system. Furthermore, by taking into account
instrumental resolution effects it was found that the system relaxation time of the water–trehalose system is longer than
that of the water–sucrose system, and the system relaxation time of the protein in a hydrated environment in the presence
of disaccharides increases sensitively. These results explain the higher bioprotectant effectiveness of trehalose. Finally,
the partial MSDs of sucrose/water and trehalose/water have been evaluated. It clearly emerges from the analysis that these
are almost equivalent in the low-Q domain (0–1.7 ?−1) but differ substantially in the high-Q range (1.7–4 ?−1). These findings reveal that the lower structural sensitivity of trehalose to thermal changes is connected with the local
spatial scale. 相似文献
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Fiorentino A D'Abrosca B Pacifico S Iacovino R Mastellone C Di Blasio B Monaco P 《Bioorganic & medicinal chemistry letters》2006,16(23):6096-6101
A novel antioxidant prenylated stilbenoid, distachyasin, has been isolated from the leaves of Carex distachya. Its structure has been elucidated on the basis of the spectroscopic characteristics. Bidimensional NMR, and crystallographic data and computational calculations have furnished important data useful for the characterization and the stereochemistry of the molecule. The compound has a tetracyclic skeleton derived from carexane. The compound has been assayed, for the antioxidant activity, by measuring its capacity to scavenge the H(2)O(2), nitric oxide, superoxide radical and to inhibit formation of TBARS (thiobarbituric acid reactive species). 相似文献
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Roberto Giorda M. Clara Bonaglia Silvana Beri Francesca Novara Jill Urquhart Claudio Zucca Susan Marelli Daniela Di Benedetto Girolamo A. Vitello Santina Reitano Francesca Bisulli Massimo Mastrangelo Luigina Spaccini Elena Fontana Jill Clayton-Smith Philippe Jonveaux Marco Seri Bernardo dalla Bernardina 《American journal of human genetics》2009,85(3):394-400
Submicroscopic copy-number variations make a considerable contribution to the genetic etiology of human disease. We have analyzed subjects with idiopathic mental retardation (MR) by using whole-genome oligonucleotide-based array comparative genomic hybridization (aCGH) and identified familial and de novo recurrent Xp11.22-p11.23 duplications in males and females with MR, speech delay, and a peculiar electroencephalographic (EEG) pattern in childhood. The size of the duplications ranges from 0.8–9.2 Mb. Most affected females show preferential activation of the duplicated X chromosome. Carriers of the smallest duplication show X-linked recessive inheritance. All other affected individuals present dominant expression and comparable clinical phenotypes irrespective of sex, duplication size, and X-inactivation pattern. The majority of the rearrangements are mediated by recombination between flanking complex segmental duplications. The identification of common clinical features, including the typical EEG pattern, predisposing genomic structure, and peculiar X-inactivation pattern, suggests that duplication of Xp11.22-p11.23 constitutes a previously undescribed syndrome. 相似文献