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101.
102.
Different wild allopolyploid species of Triticeae show extensive bivalent formation at zygotene while a considerable number of multivalents is present in cultivated polyploid wheats. To study the chromosome behaviour at early meiotic stages in wild forms of tetraploid wheats Triticum turgidum and T timopheevii (2n = 4x = 28) we have analysed the synaptic pattern in fully traced spread nuclei at mid- and late zygotene and at pachytene of wild accessions of these species. The mean number of synaptonemal complex (SC) bivalents at mid-zygotene ranged from 12.22 to 13.14 among the accessions studied indicating a strong restriction of synapsis initiation to homologous chromosomes. The mean of bivalents increased at pachytene because of the transformation of multivalents into bivalents. Ring bivalents observed at metaphase I support that SC bivalents were formed by homologous chromosomes. The average values of SC bivalents at mid-zygotene in the wild forms are much higher than the average values observed in the cultivated tetraploid wheats but similar to that of a mutant line of T turgidum with a duplication that includes Ph1, the major homoeologous pairing suppressor locus. These results suggest that the efficiency of the mechanism operating in the homologous recognition for synapsis is higher in wild wheat populations than in cultivated varieties. Apparently, a relatively detrimental modification of the pairing regulating genetic system accompanied the domestication of the wild wheat forms. 相似文献
103.
Hernández-Zanuy A Carballo JL García-Cagide A Naranjo S Esquivel M 《Revista de biología tropical》2007,55(1):247-254
Permanently submerged mangrove roots (Rhizophora mangle) are the main habitat of the ascidian Ecteinascidia turbinata in Cuba. It was occasionally found on black coral (Antiphates caribeana) between 22 and 38 meters deep. This species exhibits a wide distribution in all the mangrove keys surrounding the Island of Cuba but does not occur in riparian or fringing mangroves. Populations of this species are abundant in Cuba: in 75% of the 58 localities sampled the species was present and in 57% more than 50% of the roots held at least one colony. The highest colony densities were found in the northern coast of Pinar del Rio province with values near one colony per lineal meter of mangrove root. We found the highest density (1.46 col/m) and greatest biomass at Jutías Key, with values between 25 and 660 g/m. The average of wet biomass in the studied mangroves was 73.63 g/m. 相似文献
104.
Some isolates of the nematophagous fungus Pochonia chlamydosporia promote root growth and reduce flowering time of tomato
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E.A. Zavala‐Gonzalez N. Escudero F. Lopez‐Moya A. Aranda‐Martinez A. Exposito J. Ricaño‐Rodríguez M.A. Naranjo‐Ortiz M. Ramírez‐Lepe L.V. Lopez‐Llorca 《The Annals of applied biology》2015,166(3):472-483
The fungal parasite of nematode eggs Pochonia chlamydosporia is also a root endophyte known to promote growth of some plants. In this study, we analysed the effect of nine P. chlamydosporia isolates from worldwide origin on tomato growth. Experiments were performed at different scales (Petri dish, growth chamber and greenhouse conditions) and developmental stages (seedlings, plantlets and plants). Seven P. chlamydosporia isolates significantly (P < 0.05) increased the number of secondary roots and six of those increased total weight of tomato seedlings. Six P. chlamydosporia isolates also increased root weight of tomato plantlets. Root colonisation varied between different isolates of this fungus. Again P. chlamydosporia significantly increased root growth of tomato plants under greenhouse conditions and reduced flowering and fruiting times (up to 5 and 12 days, respectively) versus uninoculated tomato plants. P. chlamydosporia increased mature fruit weight in tomato plants. The basis of the mechanisms for growth, flowering and yield promotion in tomato by the fungus are unknown. However, we found that P. chlamydosporia can produce Indole‐3‐acetic acid and solubilise mineral phosphate. These results suggest that plant hormones or nutrient ability could play an important role. Our results put forward the agronomic importance of P. chlamydosporia as biocontrol agent of plant parasitic nematodes with tomato growth promoting capabilities. 相似文献
105.
Cristian Moscoso Ariela Vergara-Jaque Valeria Márquez-Miranda Romina V. Sepúlveda Ignacio Valencia Ignacio Díaz-Franulic Fernando González-Nilo David Naranjo 《Biophysical journal》2012,103(6):1198-1207
Potassium channels exhibit a large diversity of single-channel conductances. Shaker is a low-conductance K-channel in which Pro475→Asp, a single-point mutation near the internal pore entrance, promotes 6- to 8-fold higher unitary current. To assess the mechanism for this higher conductance, we measured Shaker-P475D single-channel current in a wide range of symmetrical K+ concentrations and voltages. Below 300 mM K+, the current-to-voltage relations (i-V) showed inward rectification that disappeared at 1000 mM K+. Single-channel conductance reached a maximum of ~190 pS at saturating [K+], a value 4- to 5-fold larger than that estimated for the native channel. Intracellular Mg2+ blocked this variant with ~100-fold higher affinity. Near zero voltage, blockade was competitively antagonized by K+; however, at voltages >100 mV, it was enhanced by K+. This result is consistent with a lock-in effect in a single-file diffusion regime of Mg2+ and K+ along the pore. Molecular-dynamics simulations revealed higher K+ density in the pore, especially near the Asp-475 side chains, as in the high-conductance MthK bacterial channel. The molecular dynamics also showed that K+ ions bound distally can coexist with other K+ or Mg2+ in the cavity, supporting a lock-in mechanism. The maximal K+ transport rate and higher occupancy could be due to a decrease in the electrostatic energy profile for K+ throughout the pore, reducing the energy wells and barriers differentially by ~0.7 and ~2 kT, respectively. 相似文献
106.
Schmidt S Naranjo JR Brenneisen C Gundlach J Schultz C Kaube H Hinterberger T Jeanmonod D 《PloS one》2012,7(3):e31138
Objectives
Several recent studies report the presence of a specific EEG pattern named Thalamocortical Dysrhythmia (TCD) in patients with severe chronic neurogenic pain. This is of major interest since so far no neuroscientific indicator of chronic pain could be identified. We investigated whether a TCD-like pattern could be found in patients with moderate chronic back pain, and we compared patients with neuropathic and non-neuropathic pain components. We furthermore assessed the presence of psychopathology and the degree of psychological functioning and examined whether the strength of the TCD-related EEG markers is correlated with psychological symptoms and pain ratings.Design
Controlled clinical trial with age and sex matched healthy controls.Methods
Spontaneous EEG was recorded in 37 back pain patients and 37 healthy controls.Results
We were not able to observe a statistically significant TCD effect in the EEG data of the whole patient group, but a subsample of patients with evidence for root damage showed a trend in this direction. Pain patients showed markedly increased psychopathology. In addition, patients'' ratings of pain intensity within the last 1 to 12 months showed strong correlations with EEG power, while psychopathology was correlated to the peak frequency.Conclusion
Out of several possible interpretations the most likely conclusion is that only patients with severe pain as well as root lesions with consecutive thalamic deafferentation develop the typical TCD pattern. Our primary method of defining ‘neuropathic pain’ could not reliably determine if such a deafferentation was present. Nevertheless the analysis of a specific subsample as well as correlations between pain ratings, psychopathology and EEG power and peak frequency give some support to the TCD concept.Trial Registration
ClinicalTrials.gov NCT00744575相似文献107.
Naranjo V Acevedo-Whitehouse K Vicente J Gortazar C de la Fuente J 《Animal genetics》2008,39(3):316-320
An association study was carried out to examine the influence of methylmalonyl-CoA mutase (MUT) polymorphisms on the susceptibility of a well-studied wild boar population from southern Spain to develop bovine tuberculosis (bTB). To this end, we examined polymorphisms at a closely linked dinucleotide microsatellite flanking exon 2 of the MUT gene in 37 wild boars with bTB and 36 non-infected individuals. The microsatellite showed low polymorphism in the studied population, with only three alleles (MUTm-A, MUTm-B and MUTm-C) found, in contrast to the 11 alleles previously reported for domestic pigs. Our case-control study showed that the MUTm-B allele was associated with disease in a dominant pattern (odds ratio = 3.36; 95% CI = 1.05-10.72; P = 0.04), while the MUTm AA genotype appeared to have a protective effect against bTB infection (odds ratio = 4.33; 95% CI = 1.20-14.96; P = 0.02). Interestingly, infected wild boars heterozygous for MUTm AB are at an advantage (11-fold) to contain the systemic spread of the disease when compared to other genotypes, implying that a balanced polymorphism may be present in the population. These results strengthen previous observations regarding the importance of the MUT gene on bTB resistance in wild boars and indicate that polymorphisms at this locus will influence the risk of acquiring and maintaining bTB in the studied population. 相似文献
108.
Edgar Botero Carlos Naranjo Julián Aguirre 《The International Journal of Life Cycle Assessment》2008,13(2):172-174
Background, Aims and Scope In the world there are more than thirty LCA software products, but they do not have inventories or an evaluation method either
with regional applicability, especially for Colombia. A special software for Life Cycle Assessment and the Environmental Performance
Evaluation has been developed, which considers the environmental impacts generated by products during their life cycle and
processes involving productive activities. It accounts with inventories applicable to Colombia, for processes and services
like electrical energy production, transport and waste disposition. The Ecoscarcity evaluation method was adapted to Colombia
with national legislation and agreements for polluting reduction signed by country and the EPI (Environmental Points of Impact)
was established for 353 substances.
Methods The software allows users to use the methodology which corresponds to the standard ISO 14030 and 14040 directives. The database
uses the SPOLD international format. For ApeironPro software, database information used from monitoring air emissions and
effluents on factories in the region were realized by the Environmental Research Group from Pontificia Bolivariana University
and secondary type information has been obtained starting from studies realized by environmental organizations and factories
in the country which are interested in the management of quality environmental indicators. The antiquity of the information
was restricted from the last 5 years, 1998 to 2003, in order to possess temporal representativity. The Ecoscarcity method
uses information of the Environmental Ministry and Environmental Institutes of Colombia for the actual current load (F), and
target norm for total load (Fk), using information with national legislation and agreements for polluting reduction signed by the respective countries.
The software was designed in Web ambience with the database in MySQL, while the programming language was JAVA from Sun Microsystem.
Results The software has inventories for energy (electricity from coal, natural gas, fuel oil, hydroelectricity) transport (mean air,
truck, motor bus), processes (plastics, rubber, sugar, paints production, detergent production, combustion in heaters, foundry
of copper, iron, gold), waste disposal (incineration and landfill).
Discussion The Ecoscarcity method was analyzed for seven impact categories: climate change, acidification, stratospheric ozone depletion,
photo-oxidant formation, eutrophication, ecotoxicity and depletion of abiotic resources (coal, oil, natural gas, copper, nickel).
Conclusions For Colombia, the highest environmental impact is associated with the ozone layer depletion (235.7 Ecopoints/g) while the
lowest is associated with depletion of coal (8.6 × 10−7 Ecopoints/g), although this is reasonable since Colombia is the tenth largest producer of coal in the world.
Recommendations and Perspectives Latin America and Colombia need more inventories for their processes and to identify the more significant environmental impacts
of their industries. This work is an initial step in the research about Life Cycle Assessment and can also improve the work
in ecolabels for Colombia. 相似文献
109.
Antonio Naranjo Tuulikki Sokka Miguel A Descalzo Jaime Calvo-Alén Kim H?rslev-Petersen Reijo K Luukkainen Bernard Combe Gerd R Burmester Joe Devlin Gianfranco Ferraccioli Alessia Morelli Monique Hoekstra Maria Majdan Stefan Sadkiewicz Miguel Belmonte Ann-Carin Holmqvist Ernest Choy Recep Tunc Aleksander Dimic Martin Bergman Sergio Toloza Theodore Pincus the QUEST-RA Group 《Arthritis research & therapy》2008,10(2):R30
Introduction
We analyzed the prevalence of cardiovascular (CV) disease in patients with rheumatoid arthritis (RA) and its association with traditional CV risk factors, clinical features of RA, and the use of disease-modifying antirheumatic drugs (DMARDs) in a multinational cross-sectional cohort of nonselected consecutive outpatients with RA (The Questionnaires in Standard Monitoring of Patients with Rheumatoid Arthritis Program, or QUEST-RA) who were receiving regular clinical care.Methods
The study involved a clinical assessment by a rheumatologist and a self-report questionnaire by patients. The clinical assessment included a review of clinical features of RA and exposure to DMARDs over the course of RA. Comorbidities were recorded; CV morbidity included myocardial infarction, angina, coronary disease, coronary bypass surgery, and stroke. Traditional risk factors recorded were hypertension, hyperlipidemia, diabetes mellitus, smoking, physical inactivity, and body mass index. Unadjusted and adjusted hazard ratios (HRs) (95% confidence interval [CI]) for CV morbidity were calculated using Cox proportional hazard regression models.Results
Between January 2005 and October 2006, the QUEST-RA project included 4,363 patients from 48 sites in 15 countries; 78% were female, more than 90% were Caucasian, and the mean age was 57 years. The prevalence for lifetime CV events in the entire sample was 3.2% for myocardial infarction, 1.9% for stroke, and 9.3% for any CV event. The prevalence for CV risk factors was 32% for hypertension, 14% for hyperlipidemia, 8% for diabetes, 43% for ever-smoking, 73% for physical inactivity, and 18% for obesity. Traditional risk factors except obesity and physical inactivity were significantly associated with CV morbidity. There was an association between any CV event and age and male gender and between extra-articular disease and myocardial infarction. Prolonged exposure to methotrexate (HR 0.85; 95% CI 0.81 to 0.89), leflunomide (HR 0.59; 95% CI 0.43 to 0.79), sulfasalazine (HR 0.92; 95% CI 0.87 to 0.98), glucocorticoids (HR 0.95; 95% CI 0.92 to 0.98), and biologic agents (HR 0.42; 95% CI 0.21 to 0.81; P < 0.05) was associated with a reduction of the risk of CV morbidity; analyses were adjusted for traditional risk factors and countries.Conclusion
In conclusion, prolonged use of treatments such as methotrexate, sulfasalazine, leflunomide, glucocorticoids, and tumor necrosis factor-alpha blockers appears to be associated with a reduced risk of CV disease. In addition to traditional risk factors, extra-articular disease was associated with the occurrence of myocardial infarction in patients with RA. 相似文献110.
Steven E. Naranjo James R. Hagler Peter C. Ellsworth 《Biocontrol Science and Technology》2003,13(6):571-587
A large-scale study was conducted in 1996 to evaluate and demonstrate strategies for pest management of Bemisia tabaci (Gennadius) in cotton involving different insecticide regimes, application methods, and action thresholds. Here we examined the effects of the various management systems on the abundance and activity of native natural enemies. Population densities of 18 out of 20 taxa of arthropod predators were significantly higher in regimes initiated with the insect growth regulators (IGRs) buprofezin (chitin inhibitor) or pyriproxyfen (juvenile hormone analog) compared with a regime dependent on a rotation of conventional, broad-spectrum insecticides. There were no differences in predator density between the two IGR regimes, and generally no effects due to application method or action threshold level. Predator to prey ratios were significantly higher in regimes utilizing the two IGRs compared with the conventional regime, but were unaffected by application method or threshold level. Rates of parasitism by Eretmocerus eremicus Rose and Zolnerowich and Encarsia meritoria Gahan were higher in the IGR regimes compared with the conventional regime, but were unaffected by insecticide application method, or the action threshold used to initiate applications of the IGRs. Results demonstrate the selective action of these two IGRs and suggest that their use may enhance opportunities for conservation biological control in cotton systems affected by B. tabaci, especially relative to conventional insecticide alternatives. 相似文献