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911.
Brevis P Morales E Bravo JC Monasterio V Mánques B Zaror L Abaca P Toloza L 《Revista iberoamericana de micología》2010,27(4):183-185
BackgroundRhinosporidiosis is a chronic, granulomatous, and non-contagious infection, in which highly vascularized polyps (mainly present in the nasal cavity) appear. These polyps usually bleed easily.AimsTo present the case of a 14 year-old male suffering from an obstruction and injury of the right nostril due to a polypoid shaped-lesion with a raspberry-like appearance.MethodsA wide surgery resection of the base of the lesion was performed, as well as a standard histopathology procedure, including microscopic analysis with haematoxylin-eosin and Grocott staining.Results and conclusionsThe histopathology report indicated that the chronic inflammatory polyp was compatible with rhinosporidiosis. 相似文献
912.
Esther Melgarejo Miguel Ángel Medina Francisca Sánchez-Jiménez José Luis Urdiales 《Journal of physiology and biochemistry》2010,66(3):265-270
The human body is made of some 250 different cell types. From them, only a small subset of cell types is able to produce histamine.
They include some neurons, enterochromaffin-like cells, gastrin-containing cells, mast cells, basophils, and monocytes/macrophages,
among others. In spite of the reduced number of these histamine-producing cell types, they are involved in very different
physiological processes. Their deregulation is related with many highly prevalent, as well as emergent and rare diseases,
mainly those described as inflammation-dependent pathologies, including mastocytosis, basophilic leukemia, gastric ulcer,
Crohn disease, and other inflammatory bowel diseases. Furthermore, oncogenic transformation switches some non-histamine-producing
cells to a histamine producing phenotype. This is the case of melanoma, small cell lung carcinoma, and several types of neuroendocrine
tumors. The bioactive compound epigallocatechin-3-gallate (EGCG), a major component of green tea, has been shown to target
histamine-producing cells producing great alterations in their behavior, with relevant effects on their proliferative potential,
as well as their adhesion, migration, and invasion potentials. In fact, EGCG has been shown to have potent anti-inflammatory,
anti-tumoral, and anti-angiogenic effects and to be a potent inhibitor of the histamine-producing enzyme, histidine decarboxylase.
Herein, we review the many specific effects of EGCG on concrete molecular targets of histamine-producing cells and discuss
the relevance of these data to support the potential therapeutic interest of this compound to treat inflammation-dependent
diseases. 相似文献
913.
Ernesto A. Roman Pablo Rosi Mariano C. González Lebrero Rodolfo Wuilloud F. Luis González Flecha José M. Delfino Javier Santos 《Proteins》2010,78(13):2757-2768
In this work, we studied how an amphipathic peptide of the surface of the globular protein thioredoxin, TRX94‐108, acquires a native‐like structure when it becomes involved in an apolar interaction network. We designed peptide variants where the tendency to form α‐helical conformation is modulated by replacing each of the leucine amino acid residues by an alanine. The induction of structure caused by sodium dodecyl sulfate (SDS) binding was studied by capillary zone electrophoresis, circular dichroism, DOSY‐NMR, and molecular dynamics simulations (MDS). In addition, we analyzed the strength of the interaction between a C18 RP‐HPLC matrix and the peptides. The results presented here reveal that (a) critical elements in the sequence of the wild‐type peptide stabilize a SDS/peptide supramolecular cluster; (b) the hydrophobic nature of the interaction between SDS molecules and the peptide constrains the ensemble of conformations; (c) nonspecific apolar surfaces are sufficient to stabilize peptide secondary structure. Remarkably, MDS shed light on a contact network formed by a limited number of SDS molecules that serves as a structural scaffold preserving the helical conformation of this module. This mechanism might prevail when a peptide with low helical propensity is involved in structure consolidation. We suggest that folding of peptides sharing this feature does not require a preformed tightly‐packed protein core. Thus, the formation of specific tertiary interactions would be the consequence of peptide folding and not its cause. In this scenario, folding might be thought of as a process that includes unspecific rounds of structure stabilization guiding the protein to the native state. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
914.
María Bermúdez Jerónimo Puertas Luis Cea Luís Pena Luis Balairón 《Ecological Engineering》2010,36(10):1355-1364
The characteristics of the flow in vertical slot fishways depend mainly on the specific pool design, i.e., the geometry of the pool. This paper presents the results of a study on sixteen different designs of vertical slot fishways with two different slopes. The flow field is studied using both a physical-scale model and a numerical model which solves the 2D depth-averaged shallow water equations coupled with a k–? turbulence model. Several hydraulic parameters, such as the average velocity in the slot or the water depth, are considered in order to evaluate their biological efficiency. Based on the results, it appears that the length of the pool is the main geometric dimension that affects the flow in the fishway. The numerical and experimental agreement is very satisfactory. 相似文献
915.
Rafael E. Coopman Fernanda P. Fuentes-Neira Verónica F. Briceño Hernán M. Cabrera Luis J. Corcuera León A. Bravo 《Trees - Structure and Function》2010,24(2):247-259
Nothofagus nitida (Phil.) Krasser (Nothofagaceae) regenerates under the shade. Nonetheless, older seedlings are commonly found at full sun.
We tested the hypothesis that light capture and photochemical and non-photochemical energy dissipation of both photosystems
PSI and PSII adjust with ontogeny and brighter environment. Light energy partitioning in both photosystems was studied in
seedlings of different developmental stages (small 9.7 cm, tall 36 cm) under contrasting light environments (8–200 and 1,800–2,043 μmol
photons m−2 s−1) in the Chilean evergreen temperate forest. Higher A
max, dark respiration, and light compensation and saturation points in sun seedlings of both developmental stages were accompanied
by higher rates of electron transport. These seedlings also showed a high fraction of open PSII reaction centres and similar
non-photochemical quenching at high-light in both photosystems, showing no effect of developmental stage in these parameters.
Conversely, light capture, total thermal dissipation after photoinhibition, active down-regulation of antenna efficiency,
and state transitions were higher in smaller seedlings than in taller ones. These changes maintain photostasis, preventing
photodamage, while favouring a more oxidized quinone pool. There is an independent effect of seedling development and light
acclimation on this transition from shade to sun during early ontogeny. This transition reflects short-term responses of the
photosynthetic apparatus to light and longer term responses that depend on seedling developmental stage. 相似文献
916.
Changes in plasma amino acid levels in a euryhaline fish exposed to different environmental salinities 总被引:1,自引:0,他引:1
Cláudia Aragão Benjamín Costas Luis Vargas-Chacoff Ignacio Ruiz-Jarabo Maria Teresa Dinis Juan Miguel Mancera Luís E. C. Conceição 《Amino acids》2010,38(1):311-317
Previous studies have shown that Senegalese sole is partially euryhaline in the juvenile phase, being able to adapt to a wide
range of salinities in a short-time period, due to changes at the osmoregulatory and metabolic level. This study aimed to
assess the effects of acclimation of sole to a wide range of salinities, with a special emphasis on the role of plasma amino
acids during this process. Sole juveniles were acclimated for 2 weeks to different salinities: 5, 15, 25, 38, and 55 g L−1. Plasma levels of cortisol, glucose, osmolality, and free amino acids were assessed at the end. Changes in plasma levels
of cortisol, glucose, and amino acids indicate that fish reared at 5 and 55 g L−1 were facing extra energy costs. Amino acids seem to play an important role during salinity acclimation, either as energy
sources or as important osmolytes for cell volume regulation. 相似文献
917.
Alejandro Gallego Luis Rodríguez Almudena Hospido María Teresa Moreira Gumersindo Feijoo 《The International Journal of Life Cycle Assessment》2010,15(1):32-43
Background, aim, and scope
Life cycle assessment (LCA) has traditionally been considered a site-independent tool, but nowadays, there is a trend towards making LCA more site-dependent. Site-dependent characterization factors have been calculated for regional impact categories such as acidification, terrestrial and aquatic eutrophication, and smog. Specifically, for aquatic eutrophication, characterization factors have been proposed for large geographical areas (mainly European and North American countries). Those factors are not detailed enough for countries which present large geographical, climatic, and economical variability such as Spain. Therefore, this work aims to calculate the characterization factors and the normalization reference for aquatic eutrophication at a regional level, using Galicia (NW Spain), a region with increasing problems of eutrophication, as a case study. Finally, the comparison of the factors obtained here with literature values will be used to analyze the influence of spatial differentiation with increasing coverage of the causality chain. 相似文献918.
Manuel Vera Martí Cortey Núria Sanz José‐Luis García‐Marín 《Journal of Zoological Systematics and Evolutionary Research》2010,48(2):181-187
The Iberian Peninsula contains diverse populations of freshwater fish, with major river basins comprising differentiated biogeographic units. The Duero River flows through the North‐Western Iberian Peninsula and is one of the most important rivers within the Iberian glacial refuge. Brown trout (Salmo trutta) populate this whole basin, and studies using both allozyme and microsatellite loci have detected a geographically sorted distribution of genetic variation in this species. In this work, sequences of the mitochondrial control region obtained from 299 brown trout from the Duero River were compared with other Iberian and European datasets. Two differentiated haplotype groups were detected inside the Duero River basin. One of them was related to the Atlantic (AT) lineage that is present in Northern European populations, whereas the other comprised an unique group that was restricted to the inner region of the basin. The amount of divergence of this Duero group from the other brown trout populations studied is consistent with a new trout lineage (Duero, DU) that is endemic to this river basin and that diverged from other Atlantic populations during the Pleistocene. The distribution of the DU and AT quaternary lineages in the Duero River was consistent with the ichthyological pattern described in the basin that originated during the Miocene–Pliocene. Evidence of selective processes that favour the haplotypes of the DU lineage may explain this discrepancy. 相似文献
919.
Cantarelli MA Pellerano RG Del Vitto LA Marchevsky EJ Camiña JM 《Phytochemical analysis : PCA》2010,21(6):550-555
Introduction – The chemometric characterisation of two plants frequently used as food and medicinal species, Achyrocline satureioides and Achyrocline venosa (Asteraceae: Gnaphalieae), was carried out based on their mineral composition. Both species, known by the common name of ‘marcelas’, are very similar in their morphological features but they have different medicinal and food properties. Objective – To develop multivariate models for the classification of A. satureiodes and A. venosa based on their mineral content. Methodology – The analytic determinations were made by means of inductively coupled plasma optical emission spectrometry from aerial parts of the plants. An internal standard was used to evaluate the accuracy in the sample treatment and the recovery of toxic elements was studied. The multivariate methods used include principal components analysis, cluster analysis and linear discriminant analysis. Results – Classification for both A. satureioides and A. venosa was successful in all cases using only four variables: aluminium, iron, magnesium and sulphur content. The concentrations of the following elements were determined: Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sr, Ti, V, Y and Zn. Conclusions – This method is useful to identify both species in raw material in order to detect eventual errors of selection. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
920.