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101.
Leonardo Kerber Marcos César Bissaro Júnior Francisco R. Negri Jonas Pereira de Souza-Filho Edson Guilherme Annie Schmaltz Hsiou 《Historical Biology》2018,30(7):985-993
Recently, the fossil record of rodents from southwestern Brazilian Amazonia has been reviewed with regards to its diversity as well as its ecological relationships. In the reviews, the necessity to report new specimens collected with stratigraphic control was stated. Here, a new dinomyid specimen collected during a 2015 expedition to the Niterói locality, Acre River, is reported. The material is a fragment of skull with the right P4–M1 and the left P4–M2 preserved. The cheek teeth are protohypsodont, a characteristic employed to differentiate Potamarchinae dinomyids from the euhypsodont dinomyids Eumegamyinae and Tetrastylinae. The occlusal surface of the cheek teeth is composed of lophs with interruptions, showing little wear, which suggests that the specimen is not fully ontogenetically developed. The specimen has a unique combination of characters (protohypsodont and pentalophodont cheek teeth, with the leading edges of similar thickness to the trailing edges, and presence of a groove on the bottom of the infraorbital foramen) not present in other known dinomyids, which led us to erect a new taxon. The abundant and diverse fossil record of protohypsodont dinomyids suggests that an important radiative event may have occurred during the middle–late Miocene of northern South America.
http://zoobank.org/urn:lsid:zoobank.org:pub:E082C3C6-47B6-4D83-9009-A64879AAFC7A
http://www.zoobank.org/NomenclaturalActs/16235A7B-A261-445E-8DD4-940AB21DCB06 相似文献
102.
Ecological outcomes and livelihood benefits of community‐managed agroforests and second growth forests in Southeast Brazil
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![点击此处可从《Biotropica》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Saulo E. X. Franco de Souza Edson Vidal Germano de Freitas Chagas Amelia T. Elgar Pedro H. S. Brancalion 《Biotropica》2016,48(6):868-881
The Forest and Landscape Restoration movement has emerged as an approach to reconcile biodiversity conservation, ecosystem services provisioning and human well‐being in degraded landscapes, but little is known so far about the potential of different reforestation methods to achieve these objectives. Based on this gap, we assessed the ecological outcomes and local livelihood benefits of community‐managed agroforests and second growth forests to assist natural regeneration in the coastal Atlantic Forest of Brazil. We investigated and compared agroforests and secondary forests according to their structure and floristic composition in 51 circular plots of 314 m², their role in supporting local livelihoods (45 semi‐structured interviews) and the use and cultural importance of plant species (61 interviews). Agroforests and, more remarkably, managed secondary forests (1) re‐established a well‐developed forest structure, with a higher density of tree‐sized individuals and similar basal area compared to nearby old growth forests; (2) were composed by a rich array of native species, including five threatened species, but had lower species richness than old growth remnants; and (3) improved local livelihoods by supplying market valuable and culturally important plants, including 231 native ethnospecies. Overall, local production systems showed remarkable potential to engage smallholders of developing tropical countries in Forest and Landscape Restoration and contribute to achieve its overall goals. We advocate the promotion of these systems as effective Forest and Landscape Restoration approaches in multi‐scale programs and policies. 相似文献
103.
Diagrammatic Scales for Assessing Brown Eye Spot (Cercospora coffeicola) in Red and Yellow Coffee Cherries
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Paulo V. A. Azevedo de Paula Edson A. Pozza Leandro A. Santos Eugênio Chaves Matheus P. Maciel Júlio César A. Paula 《Journal of Phytopathology》2016,164(10):791-800
Brazil is the world's largest coffee producer. Brown eye spot (BES) (Cercospora coffeicola) is a major crop disease that can cause 15–30% production losses and decrease the coffee beverage quality. Although the influence of this disease on beverage quality has been studied, diagrammatic scales for assessment of the disease severity in berries are still unexplored. Thus, this study has developed and validated diagrammatic scales to assess the severity of BES. Two diagrammatic scales were designed to assess the disease in berries, which can be yellow or red depending on the cultivar. The scale of yellow berries had nine grades: grade 0: 0%; 1: 0.1–5.0%; 2: 5.1–10.0%; 3: 10.1–15.0%; 4: 15.1–20.0%; 5: 20.1–30.0%; 6: 30.1–40.0%; 7: 40.1–60.0%; and 8: higher than 60.0%, while the scale of red berries had eight grades: grade 0: 0%; 1: 0.1–2.5%; 2: 2.6–5.0%; 3: 5.1–10.0%; 4: 10.1–20.0%; 5: 20.1–30.0%; 6: 30.1–50.0%; and 7: higher than 50.0% severity. Using scales improved accuracy and precision with R2 = 0.99 and provided good repeatability and reproducibility of assessments of disease severity. Both scales can be used because the different berry colour influenced the accuracy and precision between the scales. 相似文献
104.
Edge effects: impact of anthropogenic activities on vegetation structure and diversity in western Umfurudzi Park,Zimbabwe
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Victor K. Muposhi Thelma C. Chademana Edson Gandiwa Never Muboko 《African Journal of Ecology》2016,54(4):450-459
Understanding the patterns and intensity of anthropogenic impacts on habitats is important in the conservation of tropical ecosystems. The aim of the study was to establish the associated edge effects of anthropogenic disturbances on vegetation in western Umfurudzi Park, Zimbabwe. Three study strata were established using distance from the boundary into the park. Vegetation attributes and anthropogenic disturbance levels data were collected in 2012. Significant differences (P < 0.05) were noted on tree and shrub density, woody plant height, woody plant diversity, grass height and grass sward width across the three strata. Land clearing, livestock grazing and firewood collection were the most frequent and pronounced disturbances occurring along the park boundary. These disturbances decreased in intensity as distance from the boundary increased. We recommend the following: (i) the need to revisit the buffer zone concept and policy measures associated with ecosystem services and goods provision for communities surrounding protected areas, (ii) engaging neighbouring communities on sustainable ways of deriving ecosystem goods and services from buffer zones and protected areas and (iii) further studies on the regeneration and recovery of cleared patches along the boundary and their use by wildlife species in the park. 相似文献
105.
An unusually high-titer human anti-Epstein Barr virus (EBV) serum and its use in the study of EBV-specific proteins synthesized in vitro and in vivo 总被引:11,自引:0,他引:11
C M Edson L K Cohen W Henle J L Strominger 《Journal of immunology (Baltimore, Md. : 1950)》1983,130(2):919-924
Sera from a patient with a chronic Epstein Barr virus (EBV) infection contained unusually high anti-EBV antibody titers (1:2560 to 1:10,240 for EA(D) and 1:5,120 to 1:40,960 for VCA). One of these serum samples was shown by immunoprecipitation to recognize at least 11 EBV-specific proteins from virus producer cells labeled in vivo and 10 EBV-specific proteins from in vitro translations of producer cell mRNA. Six of the in vivo labeled proteins (135,000, 89,000, 50,000 to 55,000 doublet, 46,000, and 34,000 daltons) are "early" by their resistance to phosphonoacetic acid, and five (350,000, 220,000, 160,000, 140,000, and 85,000 daltons) are "late" membrane and capsid proteins. The EBV-specific proteins immunoprecipitated from in vitro translations had molecular masses of 150,000, 140,000, 115,000, 52,000, 50,000, 45,000, 34,000, 29,000, 17,000, and 15,000. Subcellular fractionation studies of cells labeled in vivo revealed that the 135,000-dalton protein and part of the 50,000 to 55,000 dalton protein doublet were found in both the nuclear and the cytoplasmic fractions, and thus are good candidates to be components of the EA(D) diffuse-type immunofluorescence observed with many EA-positive sera. 相似文献
106.
N. L. Edson 《Microbiological reviews》1951,15(3):147-182
107.
108.
Edson R. Rocha Simon C. Andrews Jeffrey N. Keen Jeremy H. Brock 《FEMS microbiology letters》1992,95(2-3):207-212
A ferritin was isolated from the obligate anaerobe Bacteroides fragilis. Estimated molecular masses were 400 kDa for the holomer and 16.7 kDa for the subunits. A 30-residue N-terminal amino acid sequence was determined and found to resemble the sequences of other ferritins (human H-chain ferritin, 43% identity; Escherichia coli gen-165 product, 37% identity) and to a lesser degree, bacterioferritins (E. coli bacterioferritin, 20% identity). The protein stained positively for iron, and incorporated 59Fe when B. fragilis was grown in the presence of [59Fe]citrate. However, the isolated protein contained only about three iron atoms per molecule, and contained no detectable haem. This represents the first isolation of a ferritin protein from bacteria. It may alleviate iron toxicity in the presence of oxygen. 相似文献
109.
Blanca M. Santoyo Carlos Gonzlez‐Romero Daniel Zrate‐Zrate R. Israel Hernndez‐Benitez Vanessa Pelayo Edson Barrera Carlos H. Escalante Ayde Fuentes‐Benites Guadalupe Martínez‐Morales Julio Lpez Miguel A. Vzquez Francisco Delgado Hugo A. Jimnez‐Vzquez Joaquín Tamariz 《Chirality》2019,31(9):719-749
Enantiopure 3‐((R)‐ and 3‐((S)‐1‐phenylethyl)‐4‐oxazoline‐2‐ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N‐(R)‐ or N‐(S)‐1‐phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric induction of the 4‐ and 5‐positions of the 4‐oxazolin‐2‐one ring through thermal and MW‐promoted nucleophilic conjugated addition to Michael acceptors and alkyl halides. The resulting adducts were transformed via a cascade process into fused six‐membered carbo‐ and heterocycles. The structure of the reaction products depended on the electrophiles and reaction conditions used. Alternative isomeric 4‐methylene‐2‐oxazolidinones served as chiral precursors for a versatile and divergent approach to highly substituted cyclic carbamates. DFT quantum calculations showed that the formation of bicyclic pyranyl compounds was generated by a diastereoselective concerted hetero‐Diels‐Alder cycloaddition. 相似文献
110.
Evanoel Crizanto de Lima Frederico S. Castelo-Branco Claudia C. Maquiaveli André B. Farias Magdalena N. Rennó Nubia Boechat Edson R. Silva 《Bioorganic & medicinal chemistry》2019,27(17):3853-3859
Searching for new substances with antileishmanial activity, we synthesized and evaluated a series of α,α-difluorohydrazide and α,α-difluoramides against Leishmania amazonensis arginase (LaArg). Four α,α-difluorohydrazide derivatives showed activity against LaArg with Ki in the range of 1.3–26 μM. The study of the kinetics of LaArg inhibition showed that these substances might act via different inhibitory mechanisms or even by a combination of these. The compounds were tested against L. amazonensis promastigotes and the best result was obtained to the compound 4 (EC50 of 12.7 ± 0.3 μM). In addition, in order to obtain further insight into the binding mode of such compounds, molecular docking studies were performed to obtain additional validation of experimental results. Considering these results, it is possible to conclude that α,α-difluorohydrazide derivatives are a promising scaffold in the development of new substances against the etiological agent of leishmaniasis by targeting LaArg. 相似文献