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101.
A. Pernet D. Hoisington J. Dintinger D. Jewell C. Jiang M. Khairallah P. Letourmy J.-L. Marchand J.-C. Glaszmann D. González de León 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(3-4):540-553
The streak disease has a major effect on maize in sub-Saharan Africa. Various genetic factors for resistance to the virus
have been identified and mapped in several populations; these factors derive from different sources of resistance. We have
focused on the Réunion island source and have recently identified several factors in the D211 line. A second very resistant
line, CIRAD390, was crossed to the same susceptible parent, B73. The linkage map comprised 124 RFLP markers, of which 79 were
common with the D211×B73 map. A row-column design was used to evaluate the resistance to maize streak virus (MSV) of 191 F2:3 families under artificial infestation at two locations: Harare (Zimbabwe) and in Réunion island. Weekly ratings of resistance
were taken and disease incidence and severity calculated. QTL analyses were conducted for each scoring date and for the integration
over time of the disease scores, of incidence, and of severity. Heritability estimates (71–98%) were as high as for the D211×B73
population. Eight QTLs were detected on chromosomes 1, 2, 3, 5 (two QTLs), 6, 8, and 10. The chr1-QTL explained the highest
proportion of phenotypic variation, about 45%. The QTLs on chromosomes 1, 2, and 10 were located in the same chromosomal bin
as QTLs for MSV resistance in the D211×B73 population. In a simultaneous fit, QTLs explained together 43–67% of the phenotypic
variation. The QTLs on chromosomes 3, 5, and 6 appeared to be specific for one or the other component of the resistance. For
the chr3-QTL, resistance was contributed by the susceptible parent. There were significant QTL × environment interactions
for some of the variables studied, but QTLs were stable in the two environments. They also appeared to be stable over time.
Global gene action ranged from partial dominance to overdominance, except for disease severity. Some additional putative QTLs
were also detected. The major QTL on chromosome 1 seemed to be common to the other sources of resistance, namely Tzi4, a tolerant
line from IITA, and CML202 from CIMMYT. However, the distribution of the other QTLs within the genome revealed differences
in Réunion germplasm and across these other resistance sources. This diversity is of great importance when considering the
durability of the resistance.
Received: 15 June 1998 / Accepted: 30 January 1999 相似文献
102.
MarieLaure Arotcarena Federico N. Soria Anthony Cunha Evelyne Doudnikoff Geoffrey Prvot Jonathan Daniel Mireille BlanchardDesce Philippe Barthlmy Erwan Bezard Sylvie CrausteManciet Benjamin Dehay 《Aging cell》2022,21(4)
Parkinson''s disease (PD) is an age‐related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra, associated with the accumulation of misfolded α‐synuclein and lysosomal impairment, two events deemed interconnected. Protein aggregation is linked to defects in degradation systems such as the autophagy‐lysosomal pathway, while lysosomal dysfunction is partly related to compromised acidification. We have recently proven that acidic nanoparticles (aNPs) can re‐acidify lysosomes and ameliorate neurotoxin‐mediated dopaminergic neurodegeneration in mice. However, no lysosome‐targeted approach has yet been tested in synucleinopathy models in vivo. Here, we show that aNPs increase α‐synuclein degradation through enhancing lysosomal activity in vitro. We further demonstrate in vivo that aNPs protect nigral dopaminergic neurons from cell death, ameliorate α‐synuclein pathology, and restore lysosomal function in mice injected with PD patient‐derived Lewy body extracts carrying toxic α‐synuclein aggregates. Our results support lysosomal re‐acidification as a disease‐modifying strategy for the treatment of PD and other age‐related proteinopathies. 相似文献
103.
104.
BackgroundThe top-down analysis of nitrate influx isotherms through the Enzyme-Substrate interpretation has not withstood recent molecular and histochemical analyses of nitrate transporters. Indeed, at least four families of nitrate transporters operating at both high and/or low external nitrate concentrations, and which are located in series and/or parallel in the different cellular layers of the mature root, are involved in nitrate uptake. Accordingly, the top-down analysis of the root catalytic structure for ion transport from the Enzyme-Substrate interpretation of nitrate influx isotherms is inadequate. Moreover, the use of the Enzyme-Substrate velocity equation as a single reference in agronomic models is not suitable in its formalism to account for variations in N uptake under fluctuating environmental conditions. Therefore, a conceptual paradigm shift is required to improve the mechanistic modelling of N uptake in agronomic models.ScopeAn alternative formalism, the Flow-Force theory, was proposed in the 1970s to describe ion isotherms based upon biophysical ‘flows and forces’ relationships of non-equilibrium thermodynamics. This interpretation describes, with macroscopic parameters, the patterns of N uptake provided by a biological system such as roots. In contrast to the Enzyme-Substrate interpretation, this approach does not claim to represent molecular characteristics. Here it is shown that it is possible to combine the Flow-Force formalism with polynomial responses of nitrate influx rate induced by climatic and in planta factors in relation to nitrate availability.ConclusionsApplication of the Flow-Force formalism allows nitrate uptake to be modelled in a more realistic manner, and allows scaling-up in time and space of the regulation of nitrate uptake across the plant growth cycle. 相似文献
105.
C. H. N. Tromp A. C. M. Nanne P. J. M. Pernet R. Tukkie A. C. Bolte 《Netherlands heart journal》2011,19(3):134-136
Two pregnant patients with a sustained symptomatic maternal supraventricular arrhythmia are presented. Both patients were treated with direct-current cardioversion. Electrical cardioversion during pregnancy is a rarely applied but highly effective procedure in the treatment of maternal cardiac arrhythmias and is assumed safe for both mother and child. However, once foetal viability is reached, monitoring of the foetal heart rate is advised and facilities for immediate caesarean section should be available. 相似文献
106.
Meissner W Harnack D Hoessle N Bezard E Winter C Morgenstern R Kupsch A 《Neurochemistry international》2004,44(4):281-286
High frequency stimulation (HFS) of the subthalamic nucleus (STN) is thought to be superior to stimulation of the internal pallidum (GPi) in alleviating symptoms of Parkinson's disease (PD). However, preliminary controlled studies comparing the effectiveness of both targets have not found significant differences in the improvement of parkinsonian symptoms, but have shown that STN stimulation allows a dramatic decrease in dopaminergic medication. We have previously shown that STN-HFS increases striatal extracellular dopamine (DA) metabolites, but not DA, in both naive and 6-hydroxydopamine (6-OHDA)-lesioned rats, whereas stimulation of the entopeduncular nucleus (EP), the rodent equivalent of the internal pallidum, does not affect DA or metabolite levels. Intriguingly, STN-HFS increases striatal DA release after inhibition of DA reuptake or metabolism, suggesting that this observation may have been obscured in non-drug treated animals by rapid and effective DA reuptake. Since STN-HFS further enhances DA metabolism after DA reuptake inhibition or depletion it has been proposed that STN-HFS increases both, striatal DA release and metabolism, independently. Therefore, the present study assesses the impact of EP-HFS on striatal DA release and metabolism in normal rats after inhibition of DA reuptake or metabolism, using microdialysis. In summary, our data demonstrate that, contrary to STN stimulation, EP-HFS has no effect on striatal DA release and metabolism. Thus, the present study provides a partial explanation for the reported clinical differences, and experimental evidence for differential mechanisms of action between HFS of the internal pallidum and the STN, that are most likely related to differences in functional anatomy. 相似文献
107.
Magnard JL Le Deunff E Domenech J Rogowsky PM Testillano PS Rougier M Risueño MC Vergne P Dumas C 《Plant molecular biology》2000,44(4):559-574
Reproduction in flowering plants is characterized by double fertilization and the resulting formation of both the zygotic embryo and the associated endosperm. In many species it is possible to experimentally deviate pollen development towards an embryogenic pathway. This developmental switch, referred to as microspore embryogenesis or androgenesis, leads to the formation of embryos similar to zygotic embryos. In a screen for genes specifically expressed during early androgenesis, two maize genes were isolated by mRNA differential display. Both genes represent new molecular markers expressed at a very young stage of androgenic embryogenesis. When their expression pattern was studied during normal reproductive development, both showed early endosperm-specific expression. Investigation of the cytological features of young androgenic embryos revealed that they present a partially coenocytic organization similar to that of early endosperm. These findings suggest that maize androgenesis may possibly involve both embryogenesis and the establishment of endosperm-like components. 相似文献
108.
Alves de Sousa R Galardon E Rat M Giorgi M Artaud I 《Journal of inorganic biochemistry》2005,99(3):690-697
A series of Zn(N2S2) complexes has been prepared, and characterized. They have different nitrogen donors such as, either two amidates, two amines, two imines or one amidate and one imine. A bis-amidato dithiolato complex has been structurally characterized by single crystal X-ray diffraction analysis, and exhibits a distorted tetrahedral structure. Oxidation of all these complexes with dioxirane or anhydrous H2O2 results in the formation of a unique product, the disulfonate species. Most often, zinc was found to be released during the course of the oxidation. The bis-imine/bis-sulfonate species is the only one to retain zinc. This complex was crystallized with two pyridine molecules. Its crystal structure reveals a distorted octahedral environment around the zinc cation. 相似文献
109.
Erwan?SaouterEmail author Gert?van?Hoof 《The International Journal of Life Cycle Assessment》2002,7(2):103-114
A Life-Cycle Inventory (LCI) and Assessment (LCA) database for laundry detergents of the Procter & Gamble Company (P&G) was
constructed using SimaPro software. The input data needed to conduct a product LCI came from several different, supporting
databases to cover supplier (extraction and manufacturing of raw materials), manufacturing of the detergent product, transportation,
packaging, use and disposal stages. Manufacturing, packaging and transportation stages are usually representative of European
conditions while the use and disposal stages are country specific and represent how consumers are using a specific product
and how wastes are disposed of. The database has been constructed to allow Procter & Gamble managers to analyse detergent
products from a system-wide, functional unit point of view in a consistent, transparent and reproducible manner. For demonstrative
purpose, a life cycle inventory and a life cycle impact assessment of a P&G laundry detergent used in Belgium is presented.
The analysis showed that more than 80% of the energy consumption occurs during the consumer use stage (mainly for heating
of the water). Air and solid waste follow the same pattern, most of these being associated with die energy generation for
the use stage. More than 98% of the biological oxygen demand, however, is associated with the disposal stage even after accounting
for removal during treatment. Future challenges are the completion and/or updating of all detergent ingredient inventories. 相似文献
110.
Aide Lasa Andrea di Cesare Giovanni Tassistro Alessio Borello Stefano Gualdi Dolors Furones Noelia Carrasco Deborah Cheslett Amanda Brechon Christine Paillard Adeline Bidault Fabrice Pernet Laura Canesi Paolo Edomi Alberto Pallavicini Carla Pruzzo Luigi Vezzulli 《Environmental microbiology》2019,21(12):4548-4562
Infectious agents such as the bacteria Vibrio aestuarianus or Ostreid herpesvirus 1 have been repeatedly associated with dramatic disease outbreaks of Crassostrea gigas beds in Europe. Beside roles played by these pathogens, microbial infections in C. gigas may derive from the contribution of a larger number of microorganisms than previously thought, according to an emerging view supporting the polymicrobial nature of bivalve diseases. In this study, the microbial communities associated with a large number of C. gigas samples collected during recurrent mortality episodes at different European sites were investigated by real-time PCR and 16SrRNA gene-based microbial profiling. A new target enrichment next-generation sequencing protocol for selective capturing of 884 phylogenetic and virulence markers of the potential microbial pathogenic community in oyster tissue was developed allowing high taxonomic resolution analysis of the bivalve pathobiota. Comparative analysis of contrasting C. gigas samples conducted using these methods revealed that oyster experiencing mortality outbreaks displayed signs of microbiota disruption associated with the presence of previously undetected potential pathogenic microbial species mostly belonging to genus Vibrio and Arcobacter. The role of these species and their consortia should be targeted by future studies aiming to shed light on mechanisms underlying polymicrobial infections in C. gigas. 相似文献