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51.
Cowchock syndrome (CMTX4) is a slowly progressive X-linked recessive disorder with axonal neuropathy, deafness, and cognitive impairment. The disease locus was previously mapped to an 11 cM region at chromosome X: q24-q26. Exome sequencing of an affected individual from the originally described family identified a missense change c.1478A>T (p.Glu493Val) in AIFM1, the gene encoding apoptosis-inducing factor (AIF) mitochondrion-associated 1. The change is at a highly conserved residue and cosegregated with the phenotype in the family. AIF is an FAD-dependent NADH oxidase that is imported into mitochondria. With apoptotic insults, a N-terminal transmembrane linker is cleaved off, producing a soluble fragment that is released into the cytosol and then transported into the nucleus, where it triggers caspase-independent apoptosis. Another AIFM1 mutation that predicts p.Arg201del has recently been associated with severe mitochondrial encephalomyopathy in two infants by impairing oxidative phosphorylation. The c.1478A>T (p.Glu493Val) mutation found in the family reported here alters the redox properties of the AIF protein and results in increased cell death via apoptosis, without affecting the activity of the respiratory chain complexes. Our findings expand the spectrum of AIF-related disease and provide insight into the effects of AIFM1 mutations.  相似文献   
52.
Ostracods from ten Late Miocene coral reef complexes built by Siderastrea, Tarbellastrea and Porites, cropping out in the Messara Plain (southern Iraklion basin, central Crete), have been investigated and five assemblages have been recognised, which point to different marine environments: (1) assemblage from the basal sandy silts, dominated by very shallow inner-infralittoral species, such as Cyamocytheridea meniscus, Cyamocytheridea obstipa, Cyamocytheridea dertonensis, Cytheretta semiornata and Nonurocythereis seminulum; (2) assemblage from the coral reef complexes within which Grinioneis haidingeri, Aurila cicatricosa, Cimbaurila diecii, Tenedocythere cruciata, Pokornyella italica and Callistocythere quadrangula are dominant and point to a stable inner-infralittoral environment characterised by warm, quiet and well-oxygenated waters; (3) assemblage from the silts intercalated among the coral reef complexes, mainly characterised by Neomonoceratina laskarevi, Cytheridea acuminata, Phlyctenophora farkasi and Aurila albicans together with Callistocythere spp., Xestoleberis communis and Xestoleberis dispar, which points to a very shallow marine environment rich in aquatic vegetation; (4) assemblage from the upper silts, which records the absolute dominance of Xestoleberis species, reflecting a very shallow and highly-vegetated environment and (5) assemblage from the uppermost silty clays, dominated by Hemicytherura defiorei, Xestoleberis spp. and Palmoconcha dertobrevis, accompanied by Acanthocythereis hystrix, Cytherella scutulum, Bairdoppilata conformis, Semicytherura spp., Krithe sp., Cytheropteron alatum, Bythocypris sp. and Pseudocythere caudata, which suggest deeper marine environments probably located in the outer infralittoral/inner-circalittoral zones. The studied section has been dated by means of calcareous nannoplankton to be not younger than Zone MNN9 (Early Tortonian), which is the biostratigraphical datum recorded in the fine-grained deposits that overlie the coral reef complexes. An age not older than Tortonian can be inferred by the stratigraphical distribution of the recognized ostracods. Thus, the coral reef complexes have been tentatively referred to the Early Tortonian.  相似文献   
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Cobalt is an important oligoelement required for bacteria; if present in high concentration, exhibits toxic effects that, depending on the microorganism under investigation, may even result in growth inhibition. The photosynthetic bacterium Rhodobacter (R.) sphaeroides tolerates high cobalt concentration and bioaccumulates Co2+ ion, mostly on the cellular surface. Very little is known on the chemical fate of the bioaccumulated cobalt, thus an X-ray absorption spectroscopy investigation was conducted on R. sphaeroides cells to gain structural insights into the Co2+ binding to cellular components. X-ray absorption near-edge spectroscopy and extended X-ray absorption fine structure measurements were performed on R. sphaeroides samples containing whole cells and cell-free fractions obtained from cultures exposed to 5 mM Co2+. An octahedral coordination geometry was found for the cobalt ion, with six oxygen-ligand atoms in the first shell. In the soluble portion of the cell, cobalt was found bound to carboxylate groups, while a mixed pattern containing equivalent amount of two sulfur and two carbon atoms was found in the cell envelope fraction, suggesting the presence of carboxylate and sulfonate metal-binding functional groups, the latter arising from sulfolipids of the cell envelope.  相似文献   
55.
Few studies have investigated whether responses to nutrient supply of mixed plant communities change under combined elevated CO2 and climate warming. In this study we analyzed the response of constructed temperate grassland communities to five levels of nitrogen (N) supply, ranging from 0 to 150 kg N ha?1, under two climate scenarios. Biomass of the plant communities responded positively to N supply in the current climate, but was insensitive to N supply in the future climate. This altered response was not the result of a changing response from a single species, but all species seemed to contribute to it. The weaker response in the future climate was caused by changes in N uptake rather than by changes in nitrogen use efficiency, as community N stocks showed the same response pattern as community biomass. Climate change apparently modified the relation between fertilizer N addition and plant available N.  相似文献   
56.
Decisions of when and where to divide are crucial for cell survival and fate, and for tissue organization and homeostasis. The temporal coordination of mitotic events during cell division is essential to ensure that each daughter cell receives one copy of the genome. The spatial coordination of these events is also crucial because the cytokinetic furrow must be aligned with the axis of chromosome segregation and, in asymmetrically dividing cells, the polarity axis. Several recent papers describe how cell shape and polarity are coordinated with cell division in single cells and tissues and begin to unravel the underlying molecular mechanisms, revealing common principles and molecular players. Here, we discuss how cells regulate the spatial and temporal coordination of cell polarity with cell division.  相似文献   
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Activation of the receptor tyrosine kinase ErbB4 leads to various cellular responses such as proliferation, survival, differentiation, and chemotaxis. Two pairs of naturally occurring ErbB4 isoforms differing in their juxtamembrane (JMa/JMb) and C termini (cyt1/cyt2) have been described. To examine the role of ErbB4 in neuron migration, we cloned and stably transfected each of the four ErbB4 isoforms in ST14A cells (a neural progenitor cell line derived from the striatum of embryonic day 14 rats) endogenously expressing the other members of the ErbB family: ErbB1, ErbB2, and ErbB3. Using immunoprecipitation assays, we showed that the neuregulin-1beta1 (NRG1beta1) stimulus induced ErbB4 tyrosine phosphorylation and phosphatidylinositol 3-kinase (PI3K) recruitment and activation (as demonstrated by Akt phosphorylation) either directly (ErbB4 cyt1 isoform) or indirectly (ErbB4 cyt2 isoform). We examined the ability of the four ErbB4 isoforms to induce chemotaxis and cell proliferation in response to NRG1beta1 stimulation. Using migration assays, we observed that only ErbB4-expressing cells stimulated with NRG1beta1 showed a significant increase in migration, whereas the growth rate remained unchanged. Additional assays showed that inhibition of PI3K (but not of phospholipase Cgamma) dramatically reduced migratory activity. Our data show that ErbB4 signaling via PI3K activation plays a fundamental role in controlling NRG1beta1-induced migration.  相似文献   
59.
The species Rhoptrocentruspiceus Marshall (Hymenoptera: Braconidae) was reared from the larvae of the xylophagous beetle Psacotheahilarishilaris (Pascoe) (Coleoptera: Cerambycidae), an exotic pest of Ficus and Morus species native to eastern Asia. It was recorded in the north of Italy in September 2005. This discovery is the first report of this species as parasitoids of the yellow spotted longicorn beetle all over the world.  相似文献   
60.
Femicide, defined as the killings of females by males because they are females, is becoming recognized worldwide as an important ongoing manifestation of gender inequality. Despite its high prevalence or widespread prevalence, only a few countries have specific registries about this issue. This study aims to assemble expert opinion regarding the strategies which might feasibly be employed to promote, develop and implement an integrated and differentiated femicide data collection system in Europe at both the national and international levels. Concept mapping methodology was followed, involving 28 experts from 16 countries in generating strategies, sorting and rating them with respect to relevance and feasibility. The experts involved were all members of the EU-Cost-Action on femicide, which is a scientific network of experts on femicide and violence against women across Europe. As a result, a conceptual map emerged, consisting of 69 strategies organized in 10 clusters, which fit into two domains: “Political action” and “Technical steps”. There was consensus among participants regarding the high relevance of strategies to institutionalize national databases and raise public awareness through different stakeholders, while strategies to promote media involvement were identified as the most feasible. Differences in perceived priorities according to the level of human development index of the experts’ countries were also observed.  相似文献   
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