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801.
Nine new species of the genus Heliura are described from Brazil (H. brasiliana sp. nov., H. olivocolora sp. nov., H. pulcherrima sp. nov., and H. laerteae sp. nov.), Ecuador (H. ecuadoris sp. nov.), Peru (H. flavipennis sp. nov. and H. peruana sp. nov.), and Venezuela (Heliura albiventris sp. nov. and H. juliani sp. nov.). They are illustrated in habitus and genitalia, and their phylogenetic affinities are discussed based on morphological evidence. 相似文献
802.
Andréia M. Pazini Guilherme M. Gomes Jardel G. Villarinho Claudio da Cunha Francielle Pinheiro Ana P. O. Ferreira Carlos F. Mello Juliano Ferreira Maribel A. Rubin 《Neurochemical research》2013,38(11):2287-2294
Alzheimer’s disease (AD) is biochemically characterized by the occurrence of extracellular deposits of amyloid beta peptide (Aβ) and intracellular deposits of the hyperphosphorylated tau protein, which are causally related to the pathological hallmarks senile plaques and neurofibrillary tangles. Monoamine oxidase B (MAO-B) activity, involved in the oxidation of biogenic monoamines, is particularly high around the senile plaques and increased in AD patients in middle to late clinical stages of the disease. Selegiline is a selective and irreversible MAO-B inhibitor and, although clinical trials already shown the beneficial effect of selegiline on cognition of AD patients, its mechanism of action remains to be elucidated. Therefore, we first investigated whether selegiline reverses the impairment of object recognition memory induced by Aβ25–35 in mice, an established model of AD. In addition, we investigated whether selegiline alters MAO-B and MAO-A activities in the hippocampus, perirhinal and remaining cerebral cortices of Aβ25–35-injected male mice. Acute (1 and 10 mg/kg, p.o., immediately post-training) and subchronic (10 mg/kg, p.o., seven days after Aβ25–35 injection and immediately post-training) administration of selegiline reversed the cognitive impairment induced by Aβ25–35 (3 nmol, i.c.v.). Acute administration of selegiline (1 mg/kg, p.o.) in combination with Aβ25–35 (3 nmol) decreased MAO-B activity in the perirhinal and remaining cerebral cortices. Acute administration of selegiline (10 mg/kg, p.o.) decreased MAO-B activity in hippocampus, perirhinal and remaining cerebral cortices, regardless of Aβ25–35 or Aβ35–25 treatment. MAO-A activity was not altered by selegiline or Aβ25–35. In summary, the current findings further support a role for cortical monoaminergic transmission in the cognitive deficits observed in AD. 相似文献
803.
804.
A new Eocaiman (Alligatoridae,Crocodylia) from the Itaboraí Basin,Paleogene of Rio de Janeiro,Brazil
André E.P. Pinheiro Daniel C. Fortier Diego Pol Diógenes A. Campos Lílian P. Bergqvist 《Historical Biology》2013,25(3):327-337
A new small species of Eocaiman is described on the basis of three anterior left mandibular rami and one isolated tooth. The specimens came from the middle-upper Paleocene Itaboraí Basin (Rio de Janeiro State, Brazil; Itaboraian South American Land Mammal Age). The new taxon differs from the other two Eocaiman species, such as its small size, likely participation of the splenial in the mandibular symphysis, a reduced angle between the longitudinal axis of the symphysis and the mandibular ramus, and enlarged ninth and tenth dentary teeth (in addition to the large first and fourth dentary teeth). The participation of the splenial in the mandibular symphysis is a unique character among caimanines (with the only possible exception being Tsoabichi greenriverensis). The new taxon provides new information on the taxonomic and anatomical diversity of the genus Eocaiman, a taxon of prime importance to understand the evolutionary origins of caimans given its position as the basalmost member of Caimaninae. Furthermore, the new taxon has a relatively small body size in comparison with other species of Eocaiman, a case paralleled by other Itaboraian reptilian groups (e.g. snakes), suggesting that this ecosystem provides critical data to test the relationship between reptilian body size and climate. http://zoobank.org/83636F22-D121-4A77-9141-BE68987B6CBF 相似文献
805.
Diogo Aparecido Lopes Silva Francisco Antonio Rocco Lahr Rita Pinheiro Garcia Fausto Miguel Cereja Seixas Freire Aldo Roberto Ometto 《The International Journal of Life Cycle Assessment》2013,18(7):1404-1411
Purpose
The wood panel industry is one of the most important forest-based industries in Brazil. The medium density particleboard (MDP) is currently produced and consumed worldwide and represents about 50 % of the wood panel industry in Brazil. Unlike other regions, Brazilian MDP is produced from dedicated eucalyptus plantations and heavy fuel oil is an important energy source in MDP manufacture, which may result in a different environmental profile. This paper presents a life cycle assessment of MDP panel produced in Brazil and suggests improvement opportunities by assessing alternative production scenarios.Methods
The cradle-to-gate assessment of 1 m3 of MDP produced in Brazil considered two main subsystems: forest and industrial production. Detailed inventories for Brazilian eucalyptus production and MDP industrial production were collected as a result of technical visits to Brazilian MDP producers (foreground systems) as well as literature review (mainly background systems). The potential environmental impacts of MDP were assessed in terms of seven impact categories using CML (abiotic depletion, acidification, global warming, eutrophication, and photochemical oxidation) and USEtox (ecotoxicity and human toxicity) impact assessment methods in order to identify the main hotspots.Results and discussion
The industrial production was responsible for most of the impacts in all impact categories, except ecotoxicity (EC). The main hotspots identified were the use of heavy fuel oil (HFO) as a thermal energy source in MDP manufacture and the production of urea–formaldehyde (UF) resin used as synthetic adhesive. Glyphosate herbicide application in soil in forestry operations was the main responsible for the impacts in EC. Scenarios for HFO substitution were assessed and results showed that substituting HFO for in-mill wood residues or diesel leads to reduced environmental impacts.Conclusions
The identification of the main hotspots in the MDP life cycle can assist the wood panel industry to improve their environmental profile. Further research should focus on UF resin production in order to reduce its environmental impacts as well as the possibility of using alternatives resins. Other sources of wood for MDP production could also be investigated (e.g., pine wood and wood residues) to assess potential improvements. 相似文献806.
Marcos Vinícius Marques Pinheiro Fabrina Bolzan Martins Ana Claudia Ferreira da Cruz Ana Cristina Portugal Pinto de Carvalho Marília Contim Ventrella Wagner Campos Otoni 《In vitro cellular & developmental biology. Plant》2013,49(3):304-312
Maturation of somatic embryos of Anthurium andraeanum cv. Eidibel from embryogenic callus was evaluated. Following induction of embryogenic calli from nodal segments, tissues were transferred to 125-mL Erlenmeyer flasks containing 25 mL liquid medium, with 0, 4.52, or 9.05 μM 2,4-dichlorophenoxyacetic acid and 0, 0.47, or 2.32 μM kinetin. Callus cultures were maintained in a dark growth room at 25?±?2°C. At 45 d, the mass of embryogenic calli, number of primary and secondary somatic embryos, and percentage browning were evaluated. Nonparametric tests were used to evaluate color, texture, and somatic embryo development. The highest yield of somatic embryos was in the medium with 0.47 μM kinetin. Calli were friable, with a lower yield of secondary somatic embryos, and have minimal browning. Histology revealed polar globular somatic embryos and mature somatic embryos with defined apical and root meristematic zones, axillary buds, and primary leaves. These are important features for converting somatic embryos into plantlets. 相似文献
807.
Valdelaine Etelvina Miranda de Araújo Letícia Cavalari Pinheiro Maria Cristina de Mattos Almeida Fernanda Carvalho de Menezes Maria Helena Franco Morais Ilka Afonso Reis Renato Martins Assun??o Mariangela Carneiro 《PLoS neglected tropical diseases》2013,7(11)
Background
Visceral leishmaniasis (VL) is a vector-borne disease whose factors involved in transmission are poorly understood, especially in more urban and densely populated counties. In Brazil, the VL urbanization is a challenge for the control program. The goals were to identify the greater risk areas for human VL and the risk factors involved in transmission.Methodology
This is an ecological study on the relative risk of human VL. Spatial units of analysis were the coverage areas of the Basic Health Units (146 small-areas) of Belo Horizonte, Minas Gerais State, Brazil. Human VL cases, from 2007 to 2009 (n = 412), were obtained in the Brazilian Reportable Disease Information System. Bayesian approach was used to model the relative risk of VL including potential risk factors involved in transmission (canine infection, socioeconomic and environmental features) and to identify the small-areas of greater risk to human VL.Principal Findings
The relative risk of VL was shown to be correlated with income, education, and the number of infected dogs per inhabitants. The estimates of relative risk of VL were higher than 1.0 in 54% of the areas (79/146). The spatial modeling highlighted 14 areas with the highest relative risk of VL and 12 of them are concentrated in the northern region of the city.Conclusions
The spatial analysis used in this study is useful for the identification of small-areas according to risk of human VL and presents operational applicability in control and surveillance program in an urban environment with an unequal spatial distribution of the disease. Thus the frequent monitoring of relative risk of human VL in small-areas is important to direct and prioritize the actions of the control program in urban environment, especially in big cities. 相似文献808.
Uzeda RS Costa Kde S Santos SL Pinheiro AM De Almeida MA McAllister MM Gondim LF 《The Korean journal of parasitology》2007,45(4):295-299
The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at 4 degrees C, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1: 50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact. 相似文献
809.
Popova T Pinheiro de Carvalho MA Matasova L Medvedeva L 《Molecular and cellular biochemistry》2007,294(1-2):97-105
The changes in the regulation of at mitochondrial NADP-isocitrate dehydrogenase (NADP-ICDH) in a rat heart during have been
analysed. Increase of enzyme activity in the cytosol and mitochondria of the heart ischemia was detected. Catalytic properties
of the mitochondrial NADP-ICDH at norm and pathology have been compared on homogeneous enzyme preparations. Enzyme from the
normoxic and ischemic heart showed the same electrophoretical mobility and molecular mass. Enzyme isolated from the ischemic
heart mitochondria demonstrated higher activation energy and lower thermal stability. NADP-isocitrate dehydrogenase at the
normoxic and ischemic conditions exhibited different Km for substrates and regulatory behaviour in relation to ATP, ADP, 2-oxoglutarate, citrate, malate, reduced and oxidised glutathione.
The inhibitory effect of the Fe2+ and H2O2 mixture associated with the generation of hydroxyl radicals was lower in the ischemic enzyme. We hypothesise that the specific features of regulation behaviour of NADP-ICDH from the ischemic tissues permits the enzyme
to supply NADPH to the glutathione reductase/glutathione peroxidase system. 相似文献
810.
Mello-Silva CC Vilar MM Bezerra JC Vasconcellos MC Pinheiro J Rodrigues Mde L 《Memórias do Instituto Oswaldo Cruz》2007,102(6):671-674
The reproductive activity of Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex was evaluated. Parameters related to fecundity and fertility were observed. The snails were exposed to the LD50 (1 mg/l) of crude latex. At the first week post exposure (p.e.), the egg laying was reduced. After the fourth week p.e., an increase of the number of eggs/snail occurred. The results showed a marked reduction in the hatching of the snails, revealing an interference of latex exposure with the reproductive process of B. glabrata of E. splendens var. hislopii. The LD50 of the latex may be used as an alternative method to control the size of the populations of B. glabrata in field. 相似文献