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21.
Laura Gangoso Pascual López-López Juan Manuel Grande Ugo Mellone Rubén Limi?ana Vicente Urios Miguel Ferrer 《PloS one》2013,8(4)
Background
The adaptive transition between behavioral strategies, such as the shift from migratoriness to sedentariness, remains an outstanding question in evolutionary ecology. Density-dependent variation in the age of first breeding has been proposed as a feasible mechanism through which long-lived migratory birds with deferred sexual maturity should become sedentary to persist on islands. Although this pattern seems to hold for most raptors and herons, a few exceptions have been identified. One of these exceptions is the Eleonora’s falcon, a long-distance migratory bird, which shows one of the most peculiar adaptations in the timing of reproduction and food requirements among raptors.Methodology/Principal Findings
Here, we compiled data concerning demography, banding recoveries and satellite tracking of Eleonora’s falcons to discuss likely explanations for the exceptional behavior of this insular long-distance migratory species.Conclusions/Significance
New data reveal that Eleonora’s falcons do return to the natal colonies in their first year and young birds are able to breed. However, in contrast to previous hypothesis, the highly specialized strategy of this and other ecologically similar species, as well as the virtual lack of food during winter at breeding areas prevent them from becoming sedentary on islands. Although the ultimate mechanisms underlying the process of sedentarization remain poorly understood, the evidence provided reveal the existence of important trade-offs associated with ecological specialization that may become particularly relevant in the present context of global change. 相似文献22.
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24.
Chen Wu Cecilia Deng Elena Hilario Nick W. Albert Declan Lafferty Ella R. P. Grierson Blue J. Plunkett Caitlin Elborough Ali Saei Catrin S. Günther Hilary Ireland Alan Yocca Patrick P. Edger Laura Jaakola Katja Karppinen Adrian Grande Ritva Kylli Veli-Pekka Lehtola Andrew C. Allan Richard V. Espley David Chagn 《Molecular ecology resources》2022,22(1):345-360
Bilberry (Vaccinium myrtillus L.) belongs to the Vaccinium genus, which includes blueberries (Vaccinium spp.) and cranberry (V. macrocarpon). Unlike its cultivated relatives, bilberry remains largely undomesticated, with berry harvesting almost entirely from the wild. As such, it represents an ideal target for genomic analysis, providing comparisons with the domesticated Vaccinium species. Bilberry is prized for its taste and health properties and has provided essential nutrition for Northern European indigenous populations. It contains high concentrations of phytonutrients, with perhaps the most important being the purple colored anthocyanins, found in both skin and flesh. Here, we present the first bilberry genome assembly, comprising 12 pseudochromosomes assembled using Oxford Nanopore (ONT) and Hi-C Technologies. The pseudochromosomes represent 96.6% complete BUSCO genes with an assessed LAI score of 16.3, showing a high conservation of synteny against the blueberry genome. Kmer analysis showed an unusual third peak, indicating the sequenced samples may have been from two individuals. The alternate alleles were purged so that the final assembly represents only one haplotype. A total of 36,404 genes were annotated after nearly 48% of the assembly was masked to remove repeats. To illustrate the genome quality, we describe the complex MYBA locus, and identify the key regulating MYB genes that determine anthocyanin production. The new bilberry genome builds on the genomic resources and knowledge of Vaccinium species, to help understand the genetics underpinning some of the quality attributes that breeding programs aspire to improve. The high conservation of synteny between bilberry and blueberry genomes means that comparative genome mapping can be applied to transfer knowledge about marker-trait association between these two species, as the loci involved in key characters are orthologous. 相似文献
25.
26.
Henrique Grande Sergio de M. Rezende Thiony E. Simon Fabiana C. Félix-Hackradt José A. García-Charton Mauro Maida Ana L. B. Gaspar Ronaldo B. Francini-Filho Thierry Fredou Beatrice P. Ferreira 《Journal of fish biology》2019,94(2):210-222
This study reports the results of 5 years of monitoring reef fish post-larvae using light traps in the Bay of Tamandaré, north-east Brazil. An annotated checklist of pre-settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post-larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species-rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement-stage reef fishes in the tropical south-west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre-settlement reef fishes. 相似文献
27.
Zardoya R Castilho R Grande C Favre-Krey L Caetano S Marcato S Krey G Patarnello T 《Molecular ecology》2004,13(7):1785-1798
Population genetic structures of the mackerel (Scomber scombrus) and chub mackerel (Scomber japonicus) were studied in the Mediterranean Sea. Fragments of 272 bp (S. scomber) and 387 bp (S. japonicus) of the 5'-end of the mitochondrial control region were sequenced from spawning individuals collected off the coasts of Greece, Italy, Spain, and Portugal. High levels of mitochondrial control region haplotypic diversity (> 0.98) were found for both Scomber species. Nucleotide diversity was higher in the mackerel (0.022) than in the chub mackerel (0.017). Global F(ST) values were also higher and significant in the mackerel (0.024, P < 0.0001) as opposed to the chub mackerel (0.003, P > 0.05). Molecular variance analyses showed differential genetic structuring for these two closely related species. There is extensive gene flow between Mediterranean Sea and Atlantic Ocean populations of chub mackerel, which are organized into a larger panmictic unit. In contrast, Mediterranean Sea populations of mackerel show some degree of genetic differentiation and are structured along an east-west axis. The analysed eastern Mediterranean Sea mackerel populations (Greece, Italy) are clearly separated from that of the western Mediterranean Sea (Barcelona), which forms a panmictic unit with eastern Atlantic Ocean populations. The genetic structures of both species showed asymmetric migration patterns and indicated population expansion. 相似文献
28.
Brands M Grande YC Endermann R Gahlmann R Krüger J Raddatz S 《Bioorganic & medicinal chemistry letters》2003,13(16):2641-2645
We report the synthesis and pharmacological evaluation of new derivatives of the natural dipeptide antibiotic TAN 1057 A,B containing heterocycles either in the beta-amino acid side chain or as mimics of the urea function. In the course of this program, we identified novel analogues that display activity towards a broader panel of Gram-positive bacteriae. 相似文献
29.
Phylogenetic utility of the nuclear gene arginine decarboxylase: an example from Brassicaceae 总被引:10,自引:2,他引:8
Arginine decarboxylase (ADC) is an important enzyme in the production of
putrescine and polyamines in plants. It is encoded by a single or low-copy
nuclear gene that lacks introns in sequences studied to date. The rate of
Adc amino acid sequence evolution is similar to that of ndhF for the
angiosperm family studied. Highly conserved regions provide several target
sites for PCR priming and sequencing and aid in nucleotide and amino acid
sequence alignment across a range of taxonomic levels, while a variable
region provides an increased number of potentially informative characters
relative to ndhF for the taxa surveyed. The utility of the Adc gene in
plant molecular systematic studies is demonstrated by analysis of its
partial nucleotide sequences obtained from 13 representatives of
Brassicaceae and 3 outgroup taxa, 2 from the mustard oil clade (order
Capparales) and 1 from the related order Malvales. Two copies of the Adc
gene, Adc1 and Adc2, are found in all members of the Brassicaceae studied
to data except the basal genus Aethionema. The resulting Adc gene tree
provides robust phylogenetic data regarding relationships within the
complex mustard family, as well as independent support for proposed tribal
realignments based on other molecular data sets such as those from
chloroplast DNA.
相似文献
30.
N Grande E Precigout S Camillieri B Carcy K Moubri A Gorenflot 《Parasitology international》1998,47(4):33-279
Babesia divergens Rouen 1987 was cultivated with a high percentage of parasitized erythrocytes (30–40%) in either RPMI 1640 supplemented by 10% human serum or in a serum-free medium consisting of RPMI 1640 supplemented with 5 g/l Albumax I®. Analysis of serum and Albumax culture supernatants, using polyacrylamide gel electrophoresis, revealed the presence of at least 10 parasitic exoantigens of B. divergens with molecular weights ranging between 27 and 200 kDa. The gerbils were injected twice, at 3-week intervals, with Albumax culture supernatants or seric culture supernatants. The vaccine doses ranged from 3 μl to 1.5 ml. The highest immunofluorescent antibody titers in gerbils (in 42 days) were obtained using Albumax supernatant and Quil A saponin as adjuvant. Analysis of the gerbil humoral response by immunoprecipitation showed that only three exoantigens were immunodominant: 92 kDa, 50 kDa and 37 kDa proteins. The gerbils were challenged 3 weeks after the last vaccine injection and the maximum protection was observed with vaccine doses ranging from 30 μl to 1.5 ml of culture supernatant and Quil A adjuvant. Albumax medium-derived antigens potentiated better protection at lower dose rates than that of serous medium-derived antigens (for example the gerbil mortality was 0% when they are immunized with 30 μl of Albumax supernatant and 100% with 30 μl of seric supernatant). 相似文献