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381.
Jérémie Doiron Luc H. Boudreau Nadia Picot Benoît Villebonet Marc E. Surette Mohamed Touaibia 《Bioorganic & medicinal chemistry letters》2009,19(4):1118-1121
Novel cinnamoyl and caffeoyl clusters were synthesized by multiple Cu(I)-catalyzed [1,3]-dipolar cycloadditions and their anti-5-lipoxygenase inhibitory activity was tested. Caffeoyl cluster showed an improved 5-lipoxygenase inhibitory activity compared to caffeic acid, with caffeoyl trimer 16 and tetramer 19 showing the best 5-lipoxygenase inhibitory activity. 相似文献
382.
Csaba Lantos Anikó Gémes Juhász György Somogyi Krisztina Ötvös Pál Vági Róbert Mihály Zoltán Kristóf Norbert Somogyi János Pauk 《Plant Cell, Tissue and Organ Culture》2009,97(3):285-293
The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian (‘Szegedi
80’, ‘Szegedi 178’, and ‘Remény’) and three Spanish (‘Jeromin’, ‘Jariza’, and ‘Jaranda’) pepper genotypes was investigated.
Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore
cultures. Co-cultures with wheat, line ‘CY-45’, ovaries exhibited enhanced frequency of embryoid production than those with
pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different
pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth
habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three ‘Jariza’,
three ‘Jaranda’, and a single ‘Szegedi 80’ plant. 相似文献
383.
The effect of lauric acid and low-HLB sucrose esters (L-195, S170) on the isothermal crystallization of coconut oil was investigated by differential scanning calorimetry. The fundamental crystallization parameters, such as induction time of nucleation and crystallization rate, were obtained by using the Gompertz equation. The Gibb's free energy of nucleation was calculated via the Fisher–Turnbull equation based on the equilibrium melting temperature. All additives, investigated in this work, proved to have an inhibition effect on nucleation and crystallization kinetics of coconut oil. Our results revealed that the inhibition effect is related to the dissimilarity of the molecular characteristics between coconut oil and the additives. The equilibrium melting temperature (Tm°) of the coconut oil–additive mixtures estimated by the Hoffman–Weeks method was decreased with the addition of lauric acid and increased by using sucrose esters as additives. Micrographs showing simultaneous crystallization of coconut oil and lauric acid indicated that strong molecular interaction led to the increase in lamellar thickness resulting in the Tm° depression of coconut oil. The addition of L-195 modified the crystal morphology of coconut oil into large, dense, non-porous crystals without altering the polymorphic occurrence of coconut oil. The enhancement in lamellar thickness and crystal perfection supported the Tm° elevation of coconut oil. 相似文献
384.
Jackson Evans Kyle Boudreau Jeremy Hyman 《Ethology : formerly Zeitschrift fur Tierpsychologie》2010,116(7):588-595
Animals in urban habitats are often noticeably bold in the presence of humans. Such boldness may arise due to habituation, as urban animals learn, through repeated exposure, that passing humans do not represent a threat. However, there is growing research suggesting that: (1) inherent traits, as opposed to learned behaviour, influence which species invade urban habitats, and (2) individuals exhibit individual personality traits that limit behavioural flexibility, with the possible result that not all individuals would be able to demonstrate an appropriate level of boldness in urban environments. As a result, perhaps only birds with inherently bold personalities could successfully settle in an area of high human disturbance, and further, we might also expect to see the existence of behavioural syndromes, where boldness is correlated with variation in other behavioural traits such as aggression. In this study, we examined boldness and territorial aggression in urban and rural populations of song sparrows. We found that urban birds were bolder towards humans and that urban birds also showed higher levels of territorial aggression. We also found an overall correlation between boldness and territorial aggression, suggesting that urban boldness may be part of a behavioural syndrome. However, we see no correlation between boldness and aggression in the urban population, and thus, more work is needed to determine the mechanisms accounting for high levels of boldness and aggression urban song sparrows. 相似文献
385.
Vesna Gagic David Kleijn András Báldi Gergely Boros Helene Bracht Jørgensen Zoltán Elek Michael P. D. Garratt G. Arjen de Groot Katarina Hedlund Anikó Kovács‐Hostyánszki Lorenzo Marini Emily Martin Ines Pevere Simon G. Potts Sarah Redlich Deepa Senapathi Ingolf Steffan‐Dewenter Stanislaw Świtek Henrik G. Smith Viktória Takács Piotr Tryjanowski Wim H. van der Putten Stijn van Gils Riccardo Bommarco 《Ecology letters》2017,20(11):1427-1436
Simultaneously enhancing ecosystem services provided by biodiversity below and above ground is recommended to reduce dependence on chemical pesticides and mineral fertilisers in agriculture. However, consequences for crop yield have been poorly evaluated. Above ground, increased landscape complexity is assumed to enhance biological pest control, whereas below ground, soil organic carbon is a proxy for several yield‐supporting services. In a field experiment replicated in 114 fields across Europe, we found that fertilisation had the strongest positive effect on yield, but hindered simultaneous harnessing of below‐ and above‐ground ecosystem services. We furthermore show that enhancing natural enemies and pest control through increasing landscape complexity can prove disappointing in fields with low soil services or in intensively cropped regions. Thus, understanding ecological interdependences between land use, ecosystem services and yield is necessary to promote more environmentally friendly farming by identifying situations where ecosystem services are maximised and agrochemical inputs can be reduced. 相似文献
386.
387.
388.
Anik Dutta Fanny E. Hartmann Carolina Sardinha Francisco Bruce A. McDonald Daniel Croll 《The ISME journal》2021,15(5):1402
The adaptive potential of pathogens in novel or heterogeneous environments underpins the risk of disease epidemics. Antagonistic pleiotropy or differential resource allocation among life-history traits can constrain pathogen adaptation. However, we lack understanding of how the genetic architecture of individual traits can generate trade-offs. Here, we report a large-scale study based on 145 global strains of the fungal wheat pathogen Zymoseptoria tritici from four continents. We measured 50 life-history traits, including virulence and reproduction on 12 different wheat hosts and growth responses to several abiotic stressors. To elucidate the genetic basis of adaptation, we used genome-wide association mapping coupled with genetic correlation analyses. We show that most traits are governed by polygenic architectures and are highly heritable suggesting that adaptation proceeds mainly through allele frequency shifts at many loci. We identified negative genetic correlations among traits related to host colonization and survival in stressful environments. Such genetic constraints indicate that pleiotropic effects could limit the pathogen’s ability to cause host damage. In contrast, adaptation to abiotic stress factors was likely facilitated by synergistic pleiotropy. Our study illustrates how comprehensive mapping of life-history trait architectures across diverse environments allows to predict evolutionary trajectories of pathogens confronted with environmental perturbations.Subject terms: Population genetics, Plant sciences, Molecular evolution, Fungi 相似文献
389.
We have extended to about 75 the number of genes mapped on the Chlamydomonas moewusii and Chlamydomonas reinhardtii chloroplast DNAs (cpDNAs) by partial sequencing of the very closely related C. eugametos and C. moewusii cpDNAs and by hybridizations with Chlamydomonas chloroplast gene-specific sequences. Only four of these genes (tscA and three reading frames) have not been identified in any other algal cpDNAs and thus may be specific to Chlamydomonas. Although the C. moewusii and C. reinhardtii cpDNAs differ by complex sequence rearrangements, 38 genes scattered throughout the genome define 12 conserved clusters of closely linked loci. Aside from the rRNA operon, four of these gene clusters share similarity to evolutionarily primitive operons found in other cpDNAs, representing in fact remnants of these operons. Our results thus indicate that most of the ancestral bacterial operons that characterize the chloroplast genome organization of land plants and early-diverging photosynthetic eukaryotes have been disrupted before the emergence of the polyphyletic genus Chlamydomonas. All gene rearrangements between the C. moewusii and C. reinhardtii cpDNAs, with the exception of those accounting for the relocations of atpA, psbI and rbcL, occurred within corresponding regions of the genome. One of these rearrangements seems to have led to disruption of the ancestral region containing rpl23, rpl2, rps19, rpl16, rpl14, rpl5, rps8 and the psaA exon 1. This gene cluster, which bears striking similarity to the Escherichia coli S10 and spc operons, spans a continuous DNA segment in C. reinhardtii, while it maps to two separate fragments in C. moewusii. 相似文献
390.
Mohammad Tuhin ali Mohammed Monzur Morshed Md. Amran Gazi Md. Abu Musa Md Golam Kibria Md Jashim Uddin Md. Anik Ashfaq Khan Shihab Hasan 《Bioinformation》2014,10(8):533-538
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) belongs to the coronaviridae family. In spite of several outbreaks in
the very recent years, no vaccine against this deadly virus is developed yet. In this study, the receptor binding domain (RBD) of
Spike (S) glycoprotein of MERS-CoV was analyzed through Computational Immunology approach to identify the antigenic
determinants (epitopes). In order to do so, the sequences of S glycoprotein that belong to different geographical regions were
aligned to observe the conservancy of MERS-CoV RBD. The immune parameters of this region were determined using different in
silico tools and Immune Epitope Database (IEDB). Molecular docking study was also employed to check the affinity of the potential
epitope towards the binding cleft of the specific HLA allele. The N-terminus RBD (S367-S606) of S glycoprotein was found to be
conserved among all the available strains of MERS-CoV. Based on the lower IC50 value, a total of eight potential T-cell epitopes and
19 major histocompatibility complex (MHC) class-I alleles were identified for this conserved region. A 9-mer epitope CYSSLILDY
displayed interactions with the maximum number of MHC class-I molecules and projected the highest peak in the B-cell
antigenicity plot which concludes that it could be a better choice for designing an epitope based peptide vaccine against MERSCoV
considering that it must undergo further in vitro and in vivo experiments. Moreover, in molecular docking study, this epitope
was found to have a significant binding affinity of -8.5 kcal/mol towards the binding cleft of the HLA-C*12:03 molecule. 相似文献