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71.
This paper focuses on the contributions to natural history, particularly in methods of plant classification of the Portuguese
botanist, man of letters, diplomat, and Freemason Abbé José Correia da Serra (1751–1823), placing them in their national and
international political and social contexts.
Correia da Serra adopted the natural method of classification championed by the Frenchman Antoine-Laurent de Jussieu, and
introduced refinements of his own that owe much to parallel developments in zoology. He endorsed the view that the classification
of plants should be based on the establishment of affinities rather than of differences. The emphasis on affinities went hand
in hand with the development of the concept of symmetry. This idea was introduced by Correia da Serra in systematics and was
adopted and further developed by his friend, Augustin-Pyramus de Candolle. Correia da Serra also argued that Cryptogamia reproduce sexually, advocated extension of methods of comparative anatomy from zoology to botany, and applied them to the
study of fruits.
Correia da Serra was one among many of the estrangeirados, Portuguese``Europeanized' intellectuals who traveled extensively abroad in most cases to escape political or religious
persecution at home. The estrangeirados were important contributors to 18th and 19th century European thinking. Most of the estrangeirados were pivotal in the introduction, dissemination and propagation of the new sciences in Portugal, but unlike most of his fellow
estrangeirados, Correia da Serra was also an innovative man of science in his own right.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
72.
To improve phylogenetic resolution of the Colletotrichum gloeosporioides species complex we developed and tested the performance of a new set of primers for the Apn2/MAT locus with a case study of 22 isolates. These were isolated mainly from coffee plants and represent six divergent and well characterized species within the C. gloeosporioides complex. Following previous studies on this locus, we have generated sequence data from an expanded region (> 4600 bp), revealing increased phylogenetic informativeness when compared to other commonly used markers such as ITS, β-tub2 and GS. Within the Apn2/MAT locus the ApMAT marker alone was almost as informative in terms of phylogenetic resolution as a seven-gene concatenated dataset. Our results further revealed that gene-tree discordance may come to be a common issue in resolving evolutionary relationships in the C. gloeosporioides complex, highlighting the importance of multilocus approaches. The use of state-of-the-art data analysis techniques and a highly informative dataset as employed here may abate this issue and hopefully assist in disentangling the C. gloeosporioides complex. 相似文献
73.
The draft genome sequence of Pseudomonas sp. strain M47T1, carried by the Bursaphelenchus xylophilus pinewood nematode, the causative agent of pine wilt disease, is presented. In Pseudomonas sp. strain M47T1, genes that make this a plant growth-promoting bacterium, as well as genes potentially involved in nematotoxicity, were identified. 相似文献
74.
Martha Lissete Morales Villarreal Marina Padilha Antonio Diogo Silva Vieira Bernadette Dora Gombossy de Melo Franco Rafael Chacon Ruiz Martinez Susana Marta Isay Saad 《PloS one》2013,8(12)
Species-specific Quantitative Real Time PCR (qPCR) alone and combined with the use of propidium monoazide (PMA) were used along with the plate count method to evaluate the survival of the probiotic strains Lactobacillus acidophilus La-5 and Bifidobacterium animalis subsp. lactis Bb-12, and the bacteriocinogenic and potentially probiotic strain Lactobacillus sakei subsp. sakei 2a in synbiotic (F1) and probiotic (F2) petit-suisse cheeses exposed throughout shelf-life to in vitro simulated gastrointestinal tract conditions. The three strains studied showed a reduction in their viability after the 6 h assay. Bb-12 displayed the highest survival capacity, above 72.6 and 74.6% of the initial populations, respectively, by plate count and PMA-qPCR, maintaining population levels in the range or above 6 log CFU/g. The prebiotic mix of inulin and FOS did not offer any additional protection for the strains against the simulated gastrointestinal environment. The microorganisms'' populations were comparable among the three methods at the initial time of the assay, confirming the presence of mainly viable and culturable cells. However, with the intensification of the stress induced throughout the various stages of the in vitro test, the differences among the methods increased. The qPCR was not a reliable enumeration method for the quantification of intact bacterial populations, mixed with large numbers of injured and dead bacteria, as confirmed by the scanning electron microscopy results. Furthermore, bacteria plate counts were much lower (P<0.05) than with the PMA-qPCR method, suggesting the accumulation of stressed or dead microorganisms unable to form colonies. The use of PMA overcame the qPCR inability to differentiate between dead and alive cells. The combination of PMA and species-specific qPCR in this study allowed a quick and unequivocal way of enumeration of viable closely related species incorporated into probiotic and synbiotic petit-suisse cheeses and under stress conditions. 相似文献
75.
Fantinatti BE Mazzuchelli J Valente GT Cabral-de-Mello DC Martins C 《Genetica》2011,139(10):1273-1282
B chromosomes are additional chromosomes widely studied in a diversity of eukaryotic groups, including fungi, plants and animals,
but their origin, evolution and possible functions are not clearly understood. To further understand the genomic content and
the evolutionary history of B chromosomes, classical and molecular cytogenetic analyses were conducted in the cichlid fish
Astatotilapia latifasciata, which harbor 1–2 B chromosomes. Through cytogenetic mapping of several probes, including transposable elements, rRNA genes,
a repeated DNA genomic fraction (C
0
t − 1 DNA), whole genome probes (comparative genomic hybridization), and BAC clones from Oreochromis niloticus, we found similarities between the B chromosome and the 1st chromosome pair and chromosomes harboring rRNA genes. Based on
the cytogenetic mapping data, we suggest the B chromosome may have evolved from a small chromosomal fragment followed by the
invasion of the proto-B chromosome by several repeated DNA families. 相似文献
76.
Diogo Aparecido Lopes Silva Francisco Antonio Rocco Lahr Ana Laura Raymundo Pavan Yovana M. B. Saavedra Natalia Crespo Mendes Sabrina Rodrigues Sousa Roberta Sanches Aldo Roberto Ometto 《The International Journal of Life Cycle Assessment》2014,19(10):1767-1778
Purpose
Sugarcane bagasse is one of the main agro-industrial residues which can be used to produce wood-based panels. However, more investigations related to its environmental performance assessment are needed, focusing on questions such as: Does it provide environmental benefits? What are its main environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues.Methods
The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main subsystems: bagasse generation, bagasse distribution, and PSB production. For the inventory of PSB, dataset from two previous LCA studies related to the conventional particle board production and the ethanol life cycle for the Brazilian context were used. The allocation criterion for the bagasse generation subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios were analyzed to evaluate the influence of the allocation criteria and the consumption of sugarcane bagasse.Results and discussion
All hotspots identified by CML and USETox methods are mainly related to the PSB production subsystem (24–100 % of impacts) due to heavy fuel oil, electricity, and urea-formaldehyde resin supply chain. The bagasse generation subsystem was more relevant to the eutrophication category (75 % of impacts). The bagasse distribution subsystem was not relevant because the impacts on all categories were lower than 1 %. PSB can substitute the conventional particle board mainly because of its lower contribution to abiotic depletion and ecotoxicity. Regarding land use impacts, PSB showed lower values according to all indicators (38–40 % of all impacts), which is explained by the lower demand for land occupation in comparison to that of the traditional particle board.Conclusions
PSB can replace the traditional particle board due to its better environmental performance. The analysis of the economic allocation criterion was relevant only for the EP category, being important to reduce diesel and N-based fertilizers use during sugarcane cultivation. Regarding the influence of the sugarcane bagasse consumption, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided. 相似文献77.
Anders Pape M?ller Diogo S. M. Samia Mike A. Weston Patrick-Jean Guay Daniel T. Blumstein 《PloS one》2014,9(9)
Background
All organisms may be affected by humans'' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known.Methodology/Principal Finding
We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining.Conclusions/Significance
Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior. 相似文献78.
79.
Ibogaine, a putative antiaddictive drug, is remarkable in its apparent ability to downgrade withdrawal symptoms and drug craving for extended periods of time after a single dose. Ibogaine acts as a non-competitive NMDA receptor antagonist, while NMDA has been implicated in long lasting changes in neuronal function and in the physiological basis of drug addiction. The purpose of this study was to verify if persistent changes in NMDA receptors could be shown in vivo and in vitro after a single administration of ibogaine. The time course of ibogaine effects were examined on NMDA-induced seizures and [3H] MK-801 binding to cortical membranes in mice 30min, 24, 48, and 72h post treatment. Ibogaine (80 mg/kg, ip) was effective in inhibiting convulsions induced by NMDA at 24 and 72 hours post administration. Likewise, [3H] MK-801 binding was significantly decreased at 24 and 72 h post ibogaine. No significant differences from controls were found at 30min or 48h post ibogaine. This long lasting and complex pattern of modulation of NMDA receptors prompted by a single dose of ibogaine may be associated to its antiaddictive properties. 相似文献
80.
Martini LH Souza CR Marques PB Calixto JB Yunes RA Souza DO 《Neurochemical research》2000,25(2):211-215
Glutamate is to be considered a nociceptive neurotransmitter and glutamatergic antagonists present antinoceptive activity. In this study we investigated the effects of the naturally occurring antinociceptive compounds rutin, geraniin and quercetine extracted from Phyllanthus, as well as the diterpene jatrophone, extracted from Jatropha elliptica on the binding of [3H]glutamate and [3H]GMP-PNP [a GTP analogue which binds to extracellular site(s), modulating the glutamatergic transmission] in rat brain membrane. Jatrophone inhibited [3H]glutamate binding and geraniin inhibited [3H]GMP-PNP binding. Quercetine inhibited the binding of both ligands. These results may indicate a neurochemical parameter possibly related to the antinoceptive activity of these natural compounds. 相似文献