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871.
Ecological effects of invasive alien insects 总被引:1,自引:0,他引:1
Marc Kenis Marie-Anne Auger-Rozenberg Alain Roques Laura Timms Christelle Péré Matthew J. W. Cock Josef Settele Sylvie Augustin Carlos Lopez-Vaamonde 《Biological invasions》2009,11(1):21-45
A literature survey identified 403 primary research publications that investigated the ecological effects of invasive alien
insects and/or the mechanisms underlying these effects. The majority of these studies were published in the last 8 years and
nearly two-thirds were carried out in North America. These publications concerned 72 invasive insect species, of which two
ant species, Solenopsis invicta and Linepithema humile, accounted for 18% and 14% of the studies, respectively. Most publications investigated effects on native biodiversity at
population or community level. Genetic effects and, to a lesser extent, effects on ecosystem services and processes were rarely
explored. We review the effects caused by different insect invaders according to: their ecosystem roles, i.e. herbivores,
predators, parasites, parasitoids and pollinators; the level of biological organisation at which they occur; and the direct
and indirect mechanisms underlying these effects. The best documented effects occur in invasive ants, Eurasian forest herbivores
invasive in North America, and honeybees. Impacts may occur through simple trophic interactions such as herbivory, predation
or parasitism. Alien species may also affect native species and communities through more complex mechanisms such as competition
for resources, disease transmission, apparent competition, or pollination disruption, among others. Finally, some invasive
insects, particularly forest herbivores and ants, are known to affect ecosystem processes through cascading effects. We identify
biases and gaps in our knowledge of ecological effects of invasive insects and suggest further opportunities for research.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
872.
Zoccola D Moya A Béranger GE Tambutté E Allemand D Carle GF Tambutté S 《Marine biotechnology (New York, N.Y.)》2009,11(2):260-269
Bone morphogenetic proteins (BMPs) are members of the transforming growth factor β superfamily, and have been identified by
their ability to induce bone formation in vertebrates. The biomineral-forming process, called biomineralization, is a widespread
process, present in all kingdoms of living organisms and among which stony corals are one of the major groups of calcifying
animals. Here, we report the presence of a BMP2/4 ortholog in eight species of adult corals. The synthesis of such a protein
by the calcifying epithelium of corals suggests that coral BMP2/4 plays a role in skeletogenesis, making BMP the first common
protein involved in biomineralization among Eumetazoans. In addition we show that recombinant coral BMP2/4 is able to inhibit
human BMP2-induced osteoblastic differentiation in mesenchymal C2C12 cells. We suggest that this inhibition results from a
competition between coral BMP2/4 and human BMP2, indicating conservation of binding affinity of BMP and its receptor during
evolution from corals to vertebrates. Further studies are needed to understand interactions between coral BMP2/4 and its receptors,
and, thus, the action of BMP2/4 in adult corals.
Nucleotide sequence of the coral BMP2/4 genes cloned in this study is available in the GenBank under the accession number
EU785981 (Stylophora pistillata) and EU785982 (Acropora sp.). 相似文献
873.
874.
875.
Alexandre Ottaviani Sylvie Rival-Gervier Amina Boussouar Andrea M. Foerster Delphine Rondier Sabrina Sacconi Claude Desnuelle Eric Gilson Frdrique Magdinier 《PLoS genetics》2009,5(2)
Both genetic and epigenetic alterations contribute to Facio-Scapulo-Humeral Dystrophy (FSHD), which is linked to the shortening of the array of D4Z4 repeats at the 4q35 locus. The consequence of this rearrangement remains enigmatic, but deletion of this 3.3-kb macrosatellite element might affect the expression of the FSHD-associated gene(s) through position effect mechanisms. We investigated this hypothesis by creating a large collection of constructs carrying 1 to >11 D4Z4 repeats integrated into the human genome, either at random sites or proximal to a telomere, mimicking thereby the organization of the 4q35 locus. We show that D4Z4 acts as an insulator that interferes with enhancer–promoter communication and protects transgenes from position effect. This last property depends on both CTCF and A-type Lamins. We further demonstrate that both anti-silencing activity of D4Z4 and CTCF binding are lost upon multimerization of the repeat in cells from FSHD patients compared to control myoblasts from healthy individuals, suggesting that FSHD corresponds to a gain-of-function of CTCF at the residual D4Z4 repeats. We propose that contraction of the D4Z4 array contributes to FSHD physio-pathology by acting as a CTCF-dependent insulator in patients. 相似文献
876.
Xin Wang Didier Zoccola Yi Jin Liew Eric Tambutte Guoxin Cui Denis Allemand Sylvie Tambutte Manuel Aranda 《Molecular biology and evolution》2021,38(9):3543
Corals build the structural foundation of coral reefs, one of the most diverse and productive ecosystems on our planet. Although the process of coral calcification that allows corals to build these immense structures has been extensively investigated, we still know little about the evolutionary processes that allowed the soft-bodied ancestor of corals to become the ecosystem builders they are today. Using a combination of phylogenomics, proteomics, and immunohistochemistry, we show that scleractinian corals likely acquired the ability to calcify sometime between ∼308 and ∼265 Ma through a combination of lineage-specific gene duplications and the co-option of existing genes to the calcification process. Our results suggest that coral calcification did not require extensive evolutionary changes, but rather few coral-specific gene duplications and a series of small, gradual optimizations of ancestral proteins and their co-option to the calcification process. 相似文献
877.
Michaël Beaulieu Anne-Mathilde Thierry Yves Handrich Sylvie Massemin Yvon Le Maho André Ancel 《Polar Biology》2010,33(4):485-492
The use of data-loggers has permitted to explore the biology of free-ranging animals. However, this method has also been reported
to reduce reproductive success while the reasons of this deleterious effect remain poorly documented. In this study, we aimed
to identify critical periods of the breeding cycle of Adélie penguins (Pygoscelis adeliae) when the reproductive success may decrease because of instrumentation. For this purpose, we monitored 40 pairs, where one
parent was instrumented before egg laying and 30 pairs without devices (controls). These pairs were followed at least during
the incubation period but the majority was monitored during the entire breeding season. Reproductive success was affected
in pairs where males were instrumented. This was not due to extra chick mortality during chick rearing but to a significantly
lower hatching success. Moreover, the use of artificial eggs recording incubation temperatures and egg rotation indicated
that in instrumented incubating males, eggs spent as much time at optimal incubation temperatures as control eggs but were
rotated at a higher frequency. In Adélie penguins, males initiate incubation and it has been established that the early stage
of incubation is one of the most critical periods for embryonic development. The low hatching rate observed in instrumented
males was associated with a higher egg rotation rate, perhaps as a stress response to the presence of the instrument. Even
though the causal effects remain unclear, instrumentation severely affected hatching success. For these reasons, we recommend
equipping birds after the early incubation. 相似文献
878.
Xavier Giresse Sophia Ahmed Sylvie Richard‐Cervera François Delmotte 《Journal of Phytopathology》2010,158(4):321-327
Here, we describe the development of an oomycete‐specific primer pair for amplification of the cytochrome b region in plant pathogenic species that span the order Peronosporales (Phytophthora spp., downy mildews). Because of the high number of variable sites at both inter‐ and intra‐specific levels this marker provides a powerful tool for population genetics and phylogenetic studies in this taxa. We also demonstrate its potential compared with other oomycete‐specific mitochondrial markers currently available. 相似文献
879.
Antonio Cárdenas-Flores Xavier Draye Céline Bivort Sylvie Cranenbrouck Stéphane Declerck 《Mycorrhiza》2010,20(6):415-425
Vegetative compatibility and amplified fragment length polymorphism (AFLP) genotyping of in vitro multispores clonal lineages,
issued from the same ancestor culture of the arbuscular mycorrhizal fungal strain MUCL 43194 and subcultured several generations
in different locations, was assessed. Vegetative compatibility was studied by confronting the germ tubes of two spores from
the same or different clonal lineages and stained with nitrotetrazolium blue–Trypan blue and diamidinophenylindole to detect
hyphal fusions and nuclei, respectively. Further AFLP analysis of single spores was performed to assess the genetic profile
and Dice similarity between clonal lineages. Germ tubes of spores distant by as many as 69 generations were capable of fusing.
The anastomosis frequencies averaged 69% between spores from the same clonal lineage, 57% between spores from different clonal
lineages, and 0% between spores belonging to different strains. The AFLP patterns showed similarities averaging 92% within
clonal lineages and 86% between clonal lineages. Each spore presented unique genotype and some of them shared more markers
with spores from different lineages than within the same lineage. We showed that MUCL 43194 maintained self-recognition for
long periods of subcultures in vitro and that spores involved in compatibility tests had different genotypes. Our findings
suggest that MUCL 43194 maintains genetic diversity by means of anastomoses. 相似文献
880.
Gilles Ferry Sabrina Hecht Sylvie Berger Natacha Moulharat Francis Coge Gérald Guillaumet Véronique Leclerc Saïd Yous Philippe Delagrange Jean A. Boutin 《Chemico-biological interactions》2010,186(2):103-109
Quinone reductase 2 is a cytosolic enzyme which catalyses the reduction of quinones, such as menadione and coenzymes Q. Despite a relatively close sequence-based resemblance to NAD(P)H:quinone oxidoreductase 1 (QR1), it has many different features. QR2 is the third melatonin binding site (MT3). It is inhibited in the micromolar range by melatonin, and does not accept conventional phosphorylated nicotinamides as hydride donors. QR2 has a powerful capacity to activate quinones leading to unexpected toxicity situations. In the present paper, we report the characterization of three QR2 modulators: melatonin, resveratrol and S29434. The latter compound inhibits QR2 activity with an IC50 in the low nanomolar range. The potency of the modulators ranged as follows, from the least to the most potent: melatonin < resveratrol < S29434. These molecular tools might permit to explore and better understand the relationship existing between QR2 catalytic activity and the various pathological situations in which QR2 has a key role. 相似文献